| /* stb_image - v2.21 - public domain image loader - http://nothings.org/stb |
| no warranty implied; use at your own risk |
| |
| Do this: |
| #define STB_IMAGE_IMPLEMENTATION |
| before you include this file in *one* C or C++ file to create the implementation. |
| |
| // i.e. it should look like this: |
| #include ... |
| #include ... |
| #include ... |
| #define STB_IMAGE_IMPLEMENTATION |
| #include "stb_image.h" |
| |
| You can #define STBI_ASSERT(x) before the #include to avoid using assert.h. |
| And #define STBI_MALLOC, STBI_REALLOC, and STBI_FREE to avoid using malloc,realloc,free |
| |
| |
| QUICK NOTES: |
| Primarily of interest to game developers and other people who can |
| avoid problematic images and only need the trivial interface |
| |
| JPEG baseline & progressive (12 bpc/arithmetic not supported, same as stock IJG lib) |
| PNG 1/2/4/8/16-bit-per-channel |
| |
| TGA (not sure what subset, if a subset) |
| BMP non-1bpp, non-RLE |
| PSD (composited view only, no extra channels, 8/16 bit-per-channel) |
| |
| GIF (*comp always reports as 4-channel) |
| HDR (radiance rgbE format) |
| PIC (Softimage PIC) |
| PNM (PPM and PGM binary only) |
| |
| Animated GIF still needs a proper API, but here's one way to do it: |
| http://gist.github.com/urraka/685d9a6340b26b830d49 |
| |
| - decode from memory or through FILE (define STBI_NO_STDIO to remove code) |
| - decode from arbitrary I/O callbacks |
| - SIMD acceleration on x86/x64 (SSE2) and ARM (NEON) |
| |
| Full documentation under "DOCUMENTATION" below. |
| |
| |
| LICENSE |
| |
| See end of file for license information. |
| |
| RECENT REVISION HISTORY: |
| |
| 2.21 (2019-02-25) fix typo in comment |
| 2.20 (2019-02-07) support utf8 filenames in Windows; fix warnings and platform ifdefs |
| 2.19 (2018-02-11) fix warning |
| 2.18 (2018-01-30) fix warnings |
| 2.17 (2018-01-29) bugfix, 1-bit BMP, 16-bitness query, fix warnings |
| 2.16 (2017-07-23) all functions have 16-bit variants; optimizations; bugfixes |
| 2.15 (2017-03-18) fix png-1,2,4; all Imagenet JPGs; no runtime SSE detection on GCC |
| 2.14 (2017-03-03) remove deprecated STBI_JPEG_OLD; fixes for Imagenet JPGs |
| 2.13 (2016-12-04) experimental 16-bit API, only for PNG so far; fixes |
| 2.12 (2016-04-02) fix typo in 2.11 PSD fix that caused crashes |
| 2.11 (2016-04-02) 16-bit PNGS; enable SSE2 in non-gcc x64 |
| RGB-format JPEG; remove white matting in PSD; |
| allocate large structures on the stack; |
| correct channel count for PNG & BMP |
| 2.10 (2016-01-22) avoid warning introduced in 2.09 |
| 2.09 (2016-01-16) 16-bit TGA; comments in PNM files; STBI_REALLOC_SIZED |
| |
| See end of file for full revision history. |
| |
| |
| ============================ Contributors ========================= |
| |
| Image formats Extensions, features |
| Sean Barrett (jpeg, png, bmp) Jetro Lauha (stbi_info) |
| Nicolas Schulz (hdr, psd) Martin "SpartanJ" Golini (stbi_info) |
| Jonathan Dummer (tga) James "moose2000" Brown (iPhone PNG) |
| Jean-Marc Lienher (gif) Ben "Disch" Wenger (io callbacks) |
| Tom Seddon (pic) Omar Cornut (1/2/4-bit PNG) |
| Thatcher Ulrich (psd) Nicolas Guillemot (vertical flip) |
| Ken Miller (pgm, ppm) Richard Mitton (16-bit PSD) |
| github:urraka (animated gif) Junggon Kim (PNM comments) |
| Christopher Forseth (animated gif) Daniel Gibson (16-bit TGA) |
| socks-the-fox (16-bit PNG) |
| Jeremy Sawicki (handle all ImageNet JPGs) |
| Optimizations & bugfixes Mikhail Morozov (1-bit BMP) |
| Fabian "ryg" Giesen Anael Seghezzi (is-16-bit query) |
| Arseny Kapoulkine |
| John-Mark Allen |
| Carmelo J Fdez-Aguera |
| |
| Bug & warning fixes |
| Marc LeBlanc David Woo Guillaume George Martins Mozeiko |
| Christpher Lloyd Jerry Jansson Joseph Thomson Phil Jordan |
| Dave Moore Roy Eltham Hayaki Saito Nathan Reed |
| Won Chun Luke Graham Johan Duparc Nick Verigakis |
| the Horde3D community Thomas Ruf Ronny Chevalier github:rlyeh |
| Janez Zemva John Bartholomew Michal Cichon github:romigrou |
| Jonathan Blow Ken Hamada Tero Hanninen github:svdijk |
| Laurent Gomila Cort Stratton Sergio Gonzalez github:snagar |
| Aruelien Pocheville Thibault Reuille Cass Everitt github:Zelex |
| Ryamond Barbiero Paul Du Bois Engin Manap github:grim210 |
| Aldo Culquicondor Philipp Wiesemann Dale Weiler github:sammyhw |
| Oriol Ferrer Mesia Josh Tobin Matthew Gregan github:phprus |
| Julian Raschke Gregory Mullen Baldur Karlsson github:poppolopoppo |
| Christian Floisand Kevin Schmidt JR Smith github:darealshinji |
| Blazej Dariusz Roszkowski github:Michaelangel007 |
| */ |
| |
| #ifndef STBI_INCLUDE_STB_IMAGE_H |
| #define STBI_INCLUDE_STB_IMAGE_H |
| |
| // DOCUMENTATION |
| // |
| // Limitations: |
| // - no 12-bit-per-channel JPEG |
| // - no JPEGs with arithmetic coding |
| // - GIF always returns *comp=4 |
| // |
| // Basic usage (see HDR discussion below for HDR usage): |
| // int x,y,n; |
| // unsigned char *data = stbi_load(filename, &x, &y, &n, 0); |
| // // ... process data if not NULL ... |
| // // ... x = width, y = height, n = # 8-bit components per pixel ... |
| // // ... replace '0' with '1'..'4' to force that many components per pixel |
| // // ... but 'n' will always be the number that it would have been if you said 0 |
| // stbi_image_free(data) |
| // |
| // Standard parameters: |
| // int *x -- outputs image width in pixels |
| // int *y -- outputs image height in pixels |
| // int *channels_in_file -- outputs # of image components in image file |
| // int desired_channels -- if non-zero, # of image components requested in result |
| // |
| // The return value from an image loader is an 'unsigned char *' which points |
| // to the pixel data, or NULL on an allocation failure or if the image is |
| // corrupt or invalid. The pixel data consists of *y scanlines of *x pixels, |
| // with each pixel consisting of N interleaved 8-bit components; the first |
| // pixel pointed to is top-left-most in the image. There is no padding between |
| // image scanlines or between pixels, regardless of format. The number of |
| // components N is 'desired_channels' if desired_channels is non-zero, or |
| // *channels_in_file otherwise. If desired_channels is non-zero, |
| // *channels_in_file has the number of components that _would_ have been |
| // output otherwise. E.g. if you set desired_channels to 4, you will always |
| // get RGBA output, but you can check *channels_in_file to see if it's trivially |
| // opaque because e.g. there were only 3 channels in the source image. |
| // |
| // An output image with N components has the following components interleaved |
| // in this order in each pixel: |
| // |
| // N=#comp components |
| // 1 grey |
| // 2 grey, alpha |
| // 3 red, green, blue |
| // 4 red, green, blue, alpha |
| // |
| // If image loading fails for any reason, the return value will be NULL, |
| // and *x, *y, *channels_in_file will be unchanged. The function |
| // stbi_failure_reason() can be queried for an extremely brief, end-user |
| // unfriendly explanation of why the load failed. Define STBI_NO_FAILURE_STRINGS |
| // to avoid compiling these strings at all, and STBI_FAILURE_USERMSG to get slightly |
| // more user-friendly ones. |
| // |
| // Paletted PNG, BMP, GIF, and PIC images are automatically depalettized. |
| // |
| // =========================================================================== |
| // |
| // UNICODE: |
| // |
| // If compiling for Windows and you wish to use Unicode filenames, compile |
| // with |
| // #define STBI_WINDOWS_UTF8 |
| // and pass utf8-encoded filenames. Call stbi_convert_wchar_to_utf8 to convert |
| // Windows wchar_t filenames to utf8. |
| // |
| // =========================================================================== |
| // |
| // Philosophy |
| // |
| // stb libraries are designed with the following priorities: |
| // |
| // 1. easy to use |
| // 2. easy to maintain |
| // 3. good performance |
| // |
| // Sometimes I let "good performance" creep up in priority over "easy to maintain", |
| // and for best performance I may provide less-easy-to-use APIs that give higher |
| // performance, in addition to the easy-to-use ones. Nevertheless, it's important |
| // to keep in mind that from the standpoint of you, a client of this library, |
| // all you care about is #1 and #3, and stb libraries DO NOT emphasize #3 above all. |
| // |
| // Some secondary priorities arise directly from the first two, some of which |
| // provide more explicit reasons why performance can't be emphasized. |
| // |
| // - Portable ("ease of use") |
| // - Small source code footprint ("easy to maintain") |
| // - No dependencies ("ease of use") |
| // |
| // =========================================================================== |
| // |
| // I/O callbacks |
| // |
| // I/O callbacks allow you to read from arbitrary sources, like packaged |
| // files or some other source. Data read from callbacks are processed |
| // through a small internal buffer (currently 128 bytes) to try to reduce |
| // overhead. |
| // |
| // The three functions you must define are "read" (reads some bytes of data), |
| // "skip" (skips some bytes of data), "eof" (reports if the stream is at the end). |
| // |
| // =========================================================================== |
| // |
| // SIMD support |
| // |
| // The JPEG decoder will try to automatically use SIMD kernels on x86 when |
| // supported by the compiler. For ARM Neon support, you must explicitly |
| // request it. |
| // |
| // (The old do-it-yourself SIMD API is no longer supported in the current |
| // code.) |
| // |
| // On x86, SSE2 will automatically be used when available based on a run-time |
| // test; if not, the generic C versions are used as a fall-back. On ARM targets, |
| // the typical path is to have separate builds for NEON and non-NEON devices |
| // (at least this is true for iOS and Android). Therefore, the NEON support is |
| // toggled by a build flag: define STBI_NEON to get NEON loops. |
| // |
| // If for some reason you do not want to use any of SIMD code, or if |
| // you have issues compiling it, you can disable it entirely by |
| // defining STBI_NO_SIMD. |
| // |
| // =========================================================================== |
| // |
| // HDR image support (disable by defining STBI_NO_HDR) |
| // |
| // stb_image supports loading HDR images in general, and currently the Radiance |
| // .HDR file format specifically. You can still load any file through the existing |
| // interface; if you attempt to load an HDR file, it will be automatically remapped |
| // to LDR, assuming gamma 2.2 and an arbitrary scale factor defaulting to 1; |
| // both of these constants can be reconfigured through this interface: |
| // |
| // stbi_hdr_to_ldr_gamma(2.2f); |
| // stbi_hdr_to_ldr_scale(1.0f); |
| // |
| // (note, do not use _inverse_ constants; stbi_image will invert them |
| // appropriately). |
| // |
| // Additionally, there is a new, parallel interface for loading files as |
| // (linear) floats to preserve the full dynamic range: |
| // |
| // float *data = stbi_loadf(filename, &x, &y, &n, 0); |
| // |
| // If you load LDR images through this interface, those images will |
| // be promoted to floating point values, run through the inverse of |
| // constants corresponding to the above: |
| // |
| // stbi_ldr_to_hdr_scale(1.0f); |
| // stbi_ldr_to_hdr_gamma(2.2f); |
| // |
| // Finally, given a filename (or an open file or memory block--see header |
| // file for details) containing image data, you can query for the "most |
| // appropriate" interface to use (that is, whether the image is HDR or |
| // not), using: |
| // |
| // stbi_is_hdr(char *filename); |
| // |
| // =========================================================================== |
| // |
| // iPhone PNG support: |
| // |
| // By default we convert iphone-formatted PNGs back to RGB, even though |
| // they are internally encoded differently. You can disable this conversion |
| // by calling stbi_convert_iphone_png_to_rgb(0), in which case |
| // you will always just get the native iphone "format" through (which |
| // is BGR stored in RGB). |
| // |
| // Call stbi_set_unpremultiply_on_load(1) as well to force a divide per |
| // pixel to remove any premultiplied alpha *only* if the image file explicitly |
| // says there's premultiplied data (currently only happens in iPhone images, |
| // and only if iPhone convert-to-rgb processing is on). |
| // |
| // =========================================================================== |
| // |
| // ADDITIONAL CONFIGURATION |
| // |
| // - You can suppress implementation of any of the decoders to reduce |
| // your code footprint by #defining one or more of the following |
| // symbols before creating the implementation. |
| // |
| // STBI_NO_JPEG |
| // STBI_NO_PNG |
| // STBI_NO_BMP |
| // STBI_NO_PSD |
| // STBI_NO_TGA |
| // STBI_NO_GIF |
| // STBI_NO_HDR |
| // STBI_NO_PIC |
| // STBI_NO_PNM (.ppm and .pgm) |
| // |
| // - You can request *only* certain decoders and suppress all other ones |
| // (this will be more forward-compatible, as addition of new decoders |
| // doesn't require you to disable them explicitly): |
| // |
| // STBI_ONLY_JPEG |
| // STBI_ONLY_PNG |
| // STBI_ONLY_BMP |
| // STBI_ONLY_PSD |
| // STBI_ONLY_TGA |
| // STBI_ONLY_GIF |
| // STBI_ONLY_HDR |
| // STBI_ONLY_PIC |
| // STBI_ONLY_PNM (.ppm and .pgm) |
| // |
| // - If you use STBI_NO_PNG (or _ONLY_ without PNG), and you still |
| // want the zlib decoder to be available, #define STBI_SUPPORT_ZLIB |
| // |
| |
| |
| #ifndef STBI_NO_STDIO |
| #include <stdio.h> |
| #endif // STBI_NO_STDIO |
| |
| #define STBI_VERSION 1 |
| |
| enum |
| { |
| STBI_default = 0, // only used for desired_channels |
| |
| STBI_grey = 1, |
| STBI_grey_alpha = 2, |
| STBI_rgb = 3, |
| STBI_rgb_alpha = 4 |
| }; |
| |
| #include <stdlib.h> |
| typedef unsigned char stbi_uc; |
| typedef unsigned short stbi_us; |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| #ifdef STB_IMAGE_STATIC |
| #define STBIDEF static |
| #else |
| #define STBIDEF extern |
| #endif |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| // |
| // PRIMARY API - works on images of any type |
| // |
| |
| // |
| // load image by filename, open file, or memory buffer |
| // |
| |
| typedef struct |
| { |
| int (*read) (void *user,char *data,int size); // fill 'data' with 'size' bytes. return number of bytes actually read |
| void (*skip) (void *user,int n); // skip the next 'n' bytes, or 'unget' the last -n bytes if negative |
| int (*eof) (void *user); // returns nonzero if we are at end of file/data |
| } stbi_io_callbacks; |
| |
| //////////////////////////////////// |
| // |
| // 8-bits-per-channel interface |
| // |
| |
| STBIDEF stbi_uc *stbi_load_from_memory (stbi_uc const *buffer, int len , int *x, int *y, int *channels_in_file, int desired_channels); |
| STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk , void *user, int *x, int *y, int *channels_in_file, int desired_channels); |
| |
| #ifndef STBI_NO_STDIO |
| STBIDEF stbi_uc *stbi_load (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels); |
| STBIDEF stbi_uc *stbi_load_from_file (FILE *f, int *x, int *y, int *channels_in_file, int desired_channels); |
| // for stbi_load_from_file, file pointer is left pointing immediately after image |
| #endif |
| |
| #ifndef STBI_NO_GIF |
| STBIDEF stbi_uc *stbi_load_gif_from_memory(stbi_uc const *buffer, int len, int **delays, int *x, int *y, int *z, int *comp, int req_comp); |
| #endif |
| |
| #ifdef STBI_WINDOWS_UTF8 |
| STBIDEF int stbi_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input); |
| #endif |
| |
| //////////////////////////////////// |
| // |
| // 16-bits-per-channel interface |
| // |
| |
| STBIDEF stbi_us *stbi_load_16_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels); |
| STBIDEF stbi_us *stbi_load_16_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *channels_in_file, int desired_channels); |
| |
| #ifndef STBI_NO_STDIO |
| STBIDEF stbi_us *stbi_load_16 (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels); |
| STBIDEF stbi_us *stbi_load_from_file_16(FILE *f, int *x, int *y, int *channels_in_file, int desired_channels); |
| #endif |
| |
| //////////////////////////////////// |
| // |
| // float-per-channel interface |
| // |
| #ifndef STBI_NO_LINEAR |
| STBIDEF float *stbi_loadf_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels); |
| STBIDEF float *stbi_loadf_from_callbacks (stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *channels_in_file, int desired_channels); |
| |
| #ifndef STBI_NO_STDIO |
| STBIDEF float *stbi_loadf (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels); |
| STBIDEF float *stbi_loadf_from_file (FILE *f, int *x, int *y, int *channels_in_file, int desired_channels); |
| #endif |
| #endif |
| |
| #ifndef STBI_NO_HDR |
| STBIDEF void stbi_hdr_to_ldr_gamma(float gamma); |
| STBIDEF void stbi_hdr_to_ldr_scale(float scale); |
| #endif // STBI_NO_HDR |
| |
| #ifndef STBI_NO_LINEAR |
| STBIDEF void stbi_ldr_to_hdr_gamma(float gamma); |
| STBIDEF void stbi_ldr_to_hdr_scale(float scale); |
| #endif // STBI_NO_LINEAR |
| |
| // stbi_is_hdr is always defined, but always returns false if STBI_NO_HDR |
| STBIDEF int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user); |
| STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len); |
| #ifndef STBI_NO_STDIO |
| STBIDEF int stbi_is_hdr (char const *filename); |
| STBIDEF int stbi_is_hdr_from_file(FILE *f); |
| #endif // STBI_NO_STDIO |
| |
| |
| // get a VERY brief reason for failure |
| // NOT THREADSAFE |
| STBIDEF const char *stbi_failure_reason (void); |
| |
| // free the loaded image -- this is just free() |
| STBIDEF void stbi_image_free (void *retval_from_stbi_load); |
| |
| // get image dimensions & components without fully decoding |
| STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp); |
| STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp); |
| STBIDEF int stbi_is_16_bit_from_memory(stbi_uc const *buffer, int len); |
| STBIDEF int stbi_is_16_bit_from_callbacks(stbi_io_callbacks const *clbk, void *user); |
| |
| #ifndef STBI_NO_STDIO |
| STBIDEF int stbi_info (char const *filename, int *x, int *y, int *comp); |
| STBIDEF int stbi_info_from_file (FILE *f, int *x, int *y, int *comp); |
| STBIDEF int stbi_is_16_bit (char const *filename); |
| STBIDEF int stbi_is_16_bit_from_file(FILE *f); |
| #endif |
| |
| |
| |
| // for image formats that explicitly notate that they have premultiplied alpha, |
| // we just return the colors as stored in the file. set this flag to force |
| // unpremultiplication. results are undefined if the unpremultiply overflow. |
| STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply); |
| |
| // indicate whether we should process iphone images back to canonical format, |
| // or just pass them through "as-is" |
| STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert); |
| |
| // flip the image vertically, so the first pixel in the output array is the bottom left |
| STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip); |
| |
| // ZLIB client - used by PNG, available for other purposes |
| |
| STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen); |
| STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header); |
| STBIDEF char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen); |
| STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); |
| |
| STBIDEF char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen); |
| STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen); |
| |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| // |
| // |
| //// end header file ///////////////////////////////////////////////////// |
| #endif // STBI_INCLUDE_STB_IMAGE_H |
| |
| #ifdef STB_IMAGE_IMPLEMENTATION |
| |
| #if defined(STBI_ONLY_JPEG) || defined(STBI_ONLY_PNG) || defined(STBI_ONLY_BMP) \ |
| || defined(STBI_ONLY_TGA) || defined(STBI_ONLY_GIF) || defined(STBI_ONLY_PSD) \ |
| || defined(STBI_ONLY_HDR) || defined(STBI_ONLY_PIC) || defined(STBI_ONLY_PNM) \ |
| || defined(STBI_ONLY_ZLIB) |
| #ifndef STBI_ONLY_JPEG |
| #define STBI_NO_JPEG |
| #endif |
| #ifndef STBI_ONLY_PNG |
| #define STBI_NO_PNG |
| #endif |
| #ifndef STBI_ONLY_BMP |
| #define STBI_NO_BMP |
| #endif |
| #ifndef STBI_ONLY_PSD |
| #define STBI_NO_PSD |
| #endif |
| #ifndef STBI_ONLY_TGA |
| #define STBI_NO_TGA |
| #endif |
| #ifndef STBI_ONLY_GIF |
| #define STBI_NO_GIF |
| #endif |
| #ifndef STBI_ONLY_HDR |
| #define STBI_NO_HDR |
| #endif |
| #ifndef STBI_ONLY_PIC |
| #define STBI_NO_PIC |
| #endif |
| #ifndef STBI_ONLY_PNM |
| #define STBI_NO_PNM |
| #endif |
| #endif |
| |
| #if defined(STBI_NO_PNG) && !defined(STBI_SUPPORT_ZLIB) && !defined(STBI_NO_ZLIB) |
| #define STBI_NO_ZLIB |
| #endif |
| |
| |
| #include <stdarg.h> |
| #include <stddef.h> // ptrdiff_t on osx |
| #include <stdlib.h> |
| #include <string.h> |
| #include <limits.h> |
| |
| #if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR) |
| #include <math.h> // ldexp, pow |
| #endif |
| |
| #ifndef STBI_NO_STDIO |
| #include <stdio.h> |
| #endif |
| |
| #ifndef STBI_ASSERT |
| #include <assert.h> |
| #define STBI_ASSERT(x) assert(x) |
| #endif |
| |
| #ifdef __cplusplus |
| #define STBI_EXTERN extern "C" |
| #else |
| #define STBI_EXTERN extern |
| #endif |
| |
| |
| #ifndef _MSC_VER |
| #ifdef __cplusplus |
| #define stbi_inline inline |
| #else |
| #define stbi_inline |
| #endif |
| #else |
| #define stbi_inline __forceinline |
| #endif |
| |
| |
| #ifdef _MSC_VER |
| typedef unsigned short stbi__uint16; |
| typedef signed short stbi__int16; |
| typedef unsigned int stbi__uint32; |
| typedef signed int stbi__int32; |
| #else |
| #include <stdint.h> |
| typedef uint16_t stbi__uint16; |
| typedef int16_t stbi__int16; |
| typedef uint32_t stbi__uint32; |
| typedef int32_t stbi__int32; |
| #endif |
| |
| // should produce compiler error if size is wrong |
| typedef unsigned char validate_uint32[sizeof(stbi__uint32)==4 ? 1 : -1]; |
| |
| #ifdef _MSC_VER |
| #define STBI_NOTUSED(v) (void)(v) |
| #else |
| #define STBI_NOTUSED(v) (void)sizeof(v) |
| #endif |
| |
| #ifdef _MSC_VER |
| #define STBI_HAS_LROTL |
| #endif |
| |
| #ifdef STBI_HAS_LROTL |
| #define stbi_lrot(x,y) _lrotl(x,y) |
| #else |
| #define stbi_lrot(x,y) (((x) << (y)) | ((x) >> (32 - (y)))) |
| #endif |
| |
| #if defined(STBI_MALLOC) && defined(STBI_FREE) && (defined(STBI_REALLOC) || defined(STBI_REALLOC_SIZED)) |
| // ok |
| #elif !defined(STBI_MALLOC) && !defined(STBI_FREE) && !defined(STBI_REALLOC) && !defined(STBI_REALLOC_SIZED) |
| // ok |
| #else |
| #error "Must define all or none of STBI_MALLOC, STBI_FREE, and STBI_REALLOC (or STBI_REALLOC_SIZED)." |
| #endif |
| |
| #ifndef STBI_MALLOC |
| #define STBI_MALLOC(sz) malloc(sz) |
| #define STBI_REALLOC(p,newsz) realloc(p,newsz) |
| #define STBI_FREE(p) free(p) |
| #endif |
| |
| #ifndef STBI_REALLOC_SIZED |
| #define STBI_REALLOC_SIZED(p,oldsz,newsz) STBI_REALLOC(p,newsz) |
| #endif |
| |
| // x86/x64 detection |
| #if defined(__x86_64__) || defined(_M_X64) |
| #define STBI__X64_TARGET |
| #elif defined(__i386) || defined(_M_IX86) |
| #define STBI__X86_TARGET |
| #endif |
| |
| #if defined(__GNUC__) && defined(STBI__X86_TARGET) && !defined(__SSE2__) && !defined(STBI_NO_SIMD) |
| // gcc doesn't support sse2 intrinsics unless you compile with -msse2, |
| // which in turn means it gets to use SSE2 everywhere. This is unfortunate, |
| // but previous attempts to provide the SSE2 functions with runtime |
| // detection caused numerous issues. The way architecture extensions are |
| // exposed in GCC/Clang is, sadly, not really suited for one-file libs. |
| // New behavior: if compiled with -msse2, we use SSE2 without any |
| // detection; if not, we don't use it at all. |
| #define STBI_NO_SIMD |
| #endif |
| |
| #if defined(__MINGW32__) && defined(STBI__X86_TARGET) && !defined(STBI_MINGW_ENABLE_SSE2) && !defined(STBI_NO_SIMD) |
| // Note that __MINGW32__ doesn't actually mean 32-bit, so we have to avoid STBI__X64_TARGET |
| // |
| // 32-bit MinGW wants ESP to be 16-byte aligned, but this is not in the |
| // Windows ABI and VC++ as well as Windows DLLs don't maintain that invariant. |
| // As a result, enabling SSE2 on 32-bit MinGW is dangerous when not |
| // simultaneously enabling "-mstackrealign". |
| // |
| // See https://github.com/nothings/stb/issues/81 for more information. |
| // |
| // So default to no SSE2 on 32-bit MinGW. If you've read this far and added |
| // -mstackrealign to your build settings, feel free to #define STBI_MINGW_ENABLE_SSE2. |
| #define STBI_NO_SIMD |
| #endif |
| |
| #if !defined(STBI_NO_SIMD) && (defined(STBI__X86_TARGET) || defined(STBI__X64_TARGET)) |
| #define STBI_SSE2 |
| #include <emmintrin.h> |
| |
| #ifdef _MSC_VER |
| |
| #if _MSC_VER >= 1400 // not VC6 |
| #include <intrin.h> // __cpuid |
| static int stbi__cpuid3(void) |
| { |
| int info[4]; |
| __cpuid(info,1); |
| return info[3]; |
| } |
| #else |
| static int stbi__cpuid3(void) |
| { |
| int res; |
| __asm { |
| mov eax,1 |
| cpuid |
| mov res,edx |
| } |
| return res; |
| } |
| #endif |
| |
| #define STBI_SIMD_ALIGN(type, name) __declspec(align(16)) type name |
| |
| #if !defined(STBI_NO_JPEG) && defined(STBI_SSE2) |
| static int stbi__sse2_available(void) |
| { |
| int info3 = stbi__cpuid3(); |
| return ((info3 >> 26) & 1) != 0; |
| } |
| #endif |
| |
| #else // assume GCC-style if not VC++ |
| #define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16))) |
| |
| #if !defined(STBI_NO_JPEG) && defined(STBI_SSE2) |
| static int stbi__sse2_available(void) |
| { |
| // If we're even attempting to compile this on GCC/Clang, that means |
| // -msse2 is on, which means the compiler is allowed to use SSE2 |
| // instructions at will, and so are we. |
| return 1; |
| } |
| #endif |
| |
| #endif |
| #endif |
| |
| // ARM NEON |
| #if defined(STBI_NO_SIMD) && defined(STBI_NEON) |
| #undef STBI_NEON |
| #endif |
| |
| #ifdef STBI_NEON |
| #include <arm_neon.h> |
| // assume GCC or Clang on ARM targets |
| #define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16))) |
| #endif |
| |
| #ifndef STBI_SIMD_ALIGN |
| #define STBI_SIMD_ALIGN(type, name) type name |
| #endif |
| |
| /////////////////////////////////////////////// |
| // |
| // stbi__context struct and start_xxx functions |
| |
| // stbi__context structure is our basic context used by all images, so it |
| // contains all the IO context, plus some basic image information |
| typedef struct |
| { |
| stbi__uint32 img_x, img_y; |
| int img_n, img_out_n; |
| |
| stbi_io_callbacks io; |
| void *io_user_data; |
| |
| int read_from_callbacks; |
| int buflen; |
| stbi_uc buffer_start[128]; |
| |
| stbi_uc *img_buffer, *img_buffer_end; |
| stbi_uc *img_buffer_original, *img_buffer_original_end; |
| } stbi__context; |
| |
| |
| static void stbi__refill_buffer(stbi__context *s); |
| |
| // initialize a memory-decode context |
| static void stbi__start_mem(stbi__context *s, stbi_uc const *buffer, int len) |
| { |
| s->io.read = NULL; |
| s->read_from_callbacks = 0; |
| s->img_buffer = s->img_buffer_original = (stbi_uc *) buffer; |
| s->img_buffer_end = s->img_buffer_original_end = (stbi_uc *) buffer+len; |
| } |
| |
| // initialize a callback-based context |
| static void stbi__start_callbacks(stbi__context *s, stbi_io_callbacks *c, void *user) |
| { |
| s->io = *c; |
| s->io_user_data = user; |
| s->buflen = sizeof(s->buffer_start); |
| s->read_from_callbacks = 1; |
| s->img_buffer_original = s->buffer_start; |
| stbi__refill_buffer(s); |
| s->img_buffer_original_end = s->img_buffer_end; |
| } |
| |
| #ifndef STBI_NO_STDIO |
| |
| static int stbi__stdio_read(void *user, char *data, int size) |
| { |
| return (int) fread(data,1,size,(FILE*) user); |
| } |
| |
| static void stbi__stdio_skip(void *user, int n) |
| { |
| fseek((FILE*) user, n, SEEK_CUR); |
| } |
| |
| static int stbi__stdio_eof(void *user) |
| { |
| return feof((FILE*) user); |
| } |
| |
| static stbi_io_callbacks stbi__stdio_callbacks = |
| { |
| stbi__stdio_read, |
| stbi__stdio_skip, |
| stbi__stdio_eof, |
| }; |
| |
| static void stbi__start_file(stbi__context *s, FILE *f) |
| { |
| stbi__start_callbacks(s, &stbi__stdio_callbacks, (void *) f); |
| } |
| |
| //static void stop_file(stbi__context *s) { } |
| |
| #endif // !STBI_NO_STDIO |
| |
| static void stbi__rewind(stbi__context *s) |
| { |
| // conceptually rewind SHOULD rewind to the beginning of the stream, |
| // but we just rewind to the beginning of the initial buffer, because |
| // we only use it after doing 'test', which only ever looks at at most 92 bytes |
| s->img_buffer = s->img_buffer_original; |
| s->img_buffer_end = s->img_buffer_original_end; |
| } |
| |
| enum |
| { |
| STBI_ORDER_RGB, |
| STBI_ORDER_BGR |
| }; |
| |
| typedef struct |
| { |
| int bits_per_channel; |
| int num_channels; |
| int channel_order; |
| } stbi__result_info; |
| |
| #ifndef STBI_NO_JPEG |
| static int stbi__jpeg_test(stbi__context *s); |
| static void *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri); |
| static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp); |
| #endif |
| |
| #ifndef STBI_NO_PNG |
| static int stbi__png_test(stbi__context *s); |
| static void *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri); |
| static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp); |
| static int stbi__png_is16(stbi__context *s); |
| #endif |
| |
| #ifndef STBI_NO_BMP |
| static int stbi__bmp_test(stbi__context *s); |
| static void *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri); |
| static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp); |
| #endif |
| |
| #ifndef STBI_NO_TGA |
| static int stbi__tga_test(stbi__context *s); |
| static void *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri); |
| static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp); |
| #endif |
| |
| #ifndef STBI_NO_PSD |
| static int stbi__psd_test(stbi__context *s); |
| static void *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc); |
| static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp); |
| static int stbi__psd_is16(stbi__context *s); |
| #endif |
| |
| #ifndef STBI_NO_HDR |
| static int stbi__hdr_test(stbi__context *s); |
| static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri); |
| static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp); |
| #endif |
| |
| #ifndef STBI_NO_PIC |
| static int stbi__pic_test(stbi__context *s); |
| static void *stbi__pic_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri); |
| static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp); |
| #endif |
| |
| #ifndef STBI_NO_GIF |
| static int stbi__gif_test(stbi__context *s); |
| static void *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri); |
| static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y, int *z, int *comp, int req_comp); |
| static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp); |
| #endif |
| |
| #ifndef STBI_NO_PNM |
| static int stbi__pnm_test(stbi__context *s); |
| static void *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri); |
| static int stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp); |
| #endif |
| |
| // this is not threadsafe |
| static const char *stbi__g_failure_reason; |
| |
| STBIDEF const char *stbi_failure_reason(void) |
| { |
| return stbi__g_failure_reason; |
| } |
| |
| static int stbi__err(const char *str) |
| { |
| stbi__g_failure_reason = str; |
| return 0; |
| } |
| |
| static void *stbi__malloc(size_t size) |
| { |
| return STBI_MALLOC(size); |
| } |
| |
| // stb_image uses ints pervasively, including for offset calculations. |
| // therefore the largest decoded image size we can support with the |
| // current code, even on 64-bit targets, is INT_MAX. this is not a |
| // significant limitation for the intended use case. |
| // |
| // we do, however, need to make sure our size calculations don't |
| // overflow. hence a few helper functions for size calculations that |
| // multiply integers together, making sure that they're non-negative |
| // and no overflow occurs. |
| |
| // return 1 if the sum is valid, 0 on overflow. |
| // negative terms are considered invalid. |
| static int stbi__addsizes_valid(int a, int b) |
| { |
| if (b < 0) return 0; |
| // now 0 <= b <= INT_MAX, hence also |
| // 0 <= INT_MAX - b <= INTMAX. |
| // And "a + b <= INT_MAX" (which might overflow) is the |
| // same as a <= INT_MAX - b (no overflow) |
| return a <= INT_MAX - b; |
| } |
| |
| // returns 1 if the product is valid, 0 on overflow. |
| // negative factors are considered invalid. |
| static int stbi__mul2sizes_valid(int a, int b) |
| { |
| if (a < 0 || b < 0) return 0; |
| if (b == 0) return 1; // mul-by-0 is always safe |
| // portable way to check for no overflows in a*b |
| return a <= INT_MAX/b; |
| } |
| |
| // returns 1 if "a*b + add" has no negative terms/factors and doesn't overflow |
| static int stbi__mad2sizes_valid(int a, int b, int add) |
| { |
| return stbi__mul2sizes_valid(a, b) && stbi__addsizes_valid(a*b, add); |
| } |
| |
| // returns 1 if "a*b*c + add" has no negative terms/factors and doesn't overflow |
| static int stbi__mad3sizes_valid(int a, int b, int c, int add) |
| { |
| return stbi__mul2sizes_valid(a, b) && stbi__mul2sizes_valid(a*b, c) && |
| stbi__addsizes_valid(a*b*c, add); |
| } |
| |
| // returns 1 if "a*b*c*d + add" has no negative terms/factors and doesn't overflow |
| #if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR) |
| static int stbi__mad4sizes_valid(int a, int b, int c, int d, int add) |
| { |
| return stbi__mul2sizes_valid(a, b) && stbi__mul2sizes_valid(a*b, c) && |
| stbi__mul2sizes_valid(a*b*c, d) && stbi__addsizes_valid(a*b*c*d, add); |
| } |
| #endif |
| |
| // mallocs with size overflow checking |
| static void *stbi__malloc_mad2(int a, int b, int add) |
| { |
| if (!stbi__mad2sizes_valid(a, b, add)) return NULL; |
| return stbi__malloc(a*b + add); |
| } |
| |
| static void *stbi__malloc_mad3(int a, int b, int c, int add) |
| { |
| if (!stbi__mad3sizes_valid(a, b, c, add)) return NULL; |
| return stbi__malloc(a*b*c + add); |
| } |
| |
| #if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR) |
| static void *stbi__malloc_mad4(int a, int b, int c, int d, int add) |
| { |
| if (!stbi__mad4sizes_valid(a, b, c, d, add)) return NULL; |
| return stbi__malloc(a*b*c*d + add); |
| } |
| #endif |
| |
| // stbi__err - error |
| // stbi__errpf - error returning pointer to float |
| // stbi__errpuc - error returning pointer to unsigned char |
| |
| #ifdef STBI_NO_FAILURE_STRINGS |
| #define stbi__err(x,y) 0 |
| #elif defined(STBI_FAILURE_USERMSG) |
| #define stbi__err(x,y) stbi__err(y) |
| #else |
| #define stbi__err(x,y) stbi__err(x) |
| #endif |
| |
| #define stbi__errpf(x,y) ((float *)(size_t) (stbi__err(x,y)?NULL:NULL)) |
| #define stbi__errpuc(x,y) ((unsigned char *)(size_t) (stbi__err(x,y)?NULL:NULL)) |
| |
| STBIDEF void stbi_image_free(void *retval_from_stbi_load) |
| { |
| STBI_FREE(retval_from_stbi_load); |
| } |
| |
| #ifndef STBI_NO_LINEAR |
| static float *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp); |
| #endif |
| |
| #ifndef STBI_NO_HDR |
| static stbi_uc *stbi__hdr_to_ldr(float *data, int x, int y, int comp); |
| #endif |
| |
| static int stbi__vertically_flip_on_load = 0; |
| |
| STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip) |
| { |
| stbi__vertically_flip_on_load = flag_true_if_should_flip; |
| } |
| |
| static void *stbi__load_main(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc) |
| { |
| memset(ri, 0, sizeof(*ri)); // make sure it's initialized if we add new fields |
| ri->bits_per_channel = 8; // default is 8 so most paths don't have to be changed |
| ri->channel_order = STBI_ORDER_RGB; // all current input & output are this, but this is here so we can add BGR order |
| ri->num_channels = 0; |
| |
| #ifndef STBI_NO_JPEG |
| if (stbi__jpeg_test(s)) return stbi__jpeg_load(s,x,y,comp,req_comp, ri); |
| #endif |
| #ifndef STBI_NO_PNG |
| if (stbi__png_test(s)) return stbi__png_load(s,x,y,comp,req_comp, ri); |
| #endif |
| #ifndef STBI_NO_BMP |
| if (stbi__bmp_test(s)) return stbi__bmp_load(s,x,y,comp,req_comp, ri); |
| #endif |
| #ifndef STBI_NO_GIF |
| if (stbi__gif_test(s)) return stbi__gif_load(s,x,y,comp,req_comp, ri); |
| #endif |
| #ifndef STBI_NO_PSD |
| if (stbi__psd_test(s)) return stbi__psd_load(s,x,y,comp,req_comp, ri, bpc); |
| #endif |
| #ifndef STBI_NO_PIC |
| if (stbi__pic_test(s)) return stbi__pic_load(s,x,y,comp,req_comp, ri); |
| #endif |
| #ifndef STBI_NO_PNM |
| if (stbi__pnm_test(s)) return stbi__pnm_load(s,x,y,comp,req_comp, ri); |
| #endif |
| |
| #ifndef STBI_NO_HDR |
| if (stbi__hdr_test(s)) { |
| float *hdr = stbi__hdr_load(s, x,y,comp,req_comp, ri); |
| return stbi__hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp); |
| } |
| #endif |
| |
| #ifndef STBI_NO_TGA |
| // test tga last because it's a crappy test! |
| if (stbi__tga_test(s)) |
| return stbi__tga_load(s,x,y,comp,req_comp, ri); |
| #endif |
| |
| return stbi__errpuc("unknown image type", "Image not of any known type, or corrupt"); |
| } |
| |
| static stbi_uc *stbi__convert_16_to_8(stbi__uint16 *orig, int w, int h, int channels) |
| { |
| int i; |
| int img_len = w * h * channels; |
| stbi_uc *reduced; |
| |
| reduced = (stbi_uc *) stbi__malloc(img_len); |
| if (reduced == NULL) return stbi__errpuc("outofmem", "Out of memory"); |
| |
| for (i = 0; i < img_len; ++i) |
| reduced[i] = (stbi_uc)((orig[i] >> 8) & 0xFF); // top half of each byte is sufficient approx of 16->8 bit scaling |
| |
| STBI_FREE(orig); |
| return reduced; |
| } |
| |
| static stbi__uint16 *stbi__convert_8_to_16(stbi_uc *orig, int w, int h, int channels) |
| { |
| int i; |
| int img_len = w * h * channels; |
| stbi__uint16 *enlarged; |
| |
| enlarged = (stbi__uint16 *) stbi__malloc(img_len*2); |
| if (enlarged == NULL) return (stbi__uint16 *) stbi__errpuc("outofmem", "Out of memory"); |
| |
| for (i = 0; i < img_len; ++i) |
| enlarged[i] = (stbi__uint16)((orig[i] << 8) + orig[i]); // replicate to high and low byte, maps 0->0, 255->0xffff |
| |
| STBI_FREE(orig); |
| return enlarged; |
| } |
| |
| static void stbi__vertical_flip(void *image, int w, int h, int bytes_per_pixel) |
| { |
| int row; |
| size_t bytes_per_row = (size_t)w * bytes_per_pixel; |
| stbi_uc temp[2048]; |
| stbi_uc *bytes = (stbi_uc *)image; |
| |
| for (row = 0; row < (h>>1); row++) { |
| stbi_uc *row0 = bytes + row*bytes_per_row; |
| stbi_uc *row1 = bytes + (h - row - 1)*bytes_per_row; |
| // swap row0 with row1 |
| size_t bytes_left = bytes_per_row; |
| while (bytes_left) { |
| size_t bytes_copy = (bytes_left < sizeof(temp)) ? bytes_left : sizeof(temp); |
| memcpy(temp, row0, bytes_copy); |
| memcpy(row0, row1, bytes_copy); |
| memcpy(row1, temp, bytes_copy); |
| row0 += bytes_copy; |
| row1 += bytes_copy; |
| bytes_left -= bytes_copy; |
| } |
| } |
| } |
| |
| #ifndef STBI_NO_GIF |
| static void stbi__vertical_flip_slices(void *image, int w, int h, int z, int bytes_per_pixel) |
| { |
| int slice; |
| int slice_size = w * h * bytes_per_pixel; |
| |
| stbi_uc *bytes = (stbi_uc *)image; |
| for (slice = 0; slice < z; ++slice) { |
| stbi__vertical_flip(bytes, w, h, bytes_per_pixel); |
| bytes += slice_size; |
| } |
| } |
| #endif |
| |
| static unsigned char *stbi__load_and_postprocess_8bit(stbi__context *s, int *x, int *y, int *comp, int req_comp) |
| { |
| stbi__result_info ri; |
| void *result = stbi__load_main(s, x, y, comp, req_comp, &ri, 8); |
| |
| if (result == NULL) |
| return NULL; |
| |
| if (ri.bits_per_channel != 8) { |
| STBI_ASSERT(ri.bits_per_channel == 16); |
| result = stbi__convert_16_to_8((stbi__uint16 *) result, *x, *y, req_comp == 0 ? *comp : req_comp); |
| ri.bits_per_channel = 8; |
| } |
| |
| // @TODO: move stbi__convert_format to here |
| |
| if (stbi__vertically_flip_on_load) { |
| int channels = req_comp ? req_comp : *comp; |
| stbi__vertical_flip(result, *x, *y, channels * sizeof(stbi_uc)); |
| } |
| |
| return (unsigned char *) result; |
| } |
| |
| static stbi__uint16 *stbi__load_and_postprocess_16bit(stbi__context *s, int *x, int *y, int *comp, int req_comp) |
| { |
| stbi__result_info ri; |
| void *result = stbi__load_main(s, x, y, comp, req_comp, &ri, 16); |
| |
| if (result == NULL) |
| return NULL; |
| |
| if (ri.bits_per_channel != 16) { |
| STBI_ASSERT(ri.bits_per_channel == 8); |
| result = stbi__convert_8_to_16((stbi_uc *) result, *x, *y, req_comp == 0 ? *comp : req_comp); |
| ri.bits_per_channel = 16; |
| } |
| |
| // @TODO: move stbi__convert_format16 to here |
| // @TODO: special case RGB-to-Y (and RGBA-to-YA) for 8-bit-to-16-bit case to keep more precision |
| |
| if (stbi__vertically_flip_on_load) { |
| int channels = req_comp ? req_comp : *comp; |
| stbi__vertical_flip(result, *x, *y, channels * sizeof(stbi__uint16)); |
| } |
| |
| return (stbi__uint16 *) result; |
| } |
| |
| #if !defined(STBI_NO_HDR) && !defined(STBI_NO_LINEAR) |
| static void stbi__float_postprocess(float *result, int *x, int *y, int *comp, int req_comp) |
| { |
| if (stbi__vertically_flip_on_load && result != NULL) { |
| int channels = req_comp ? req_comp : *comp; |
| stbi__vertical_flip(result, *x, *y, channels * sizeof(float)); |
| } |
| } |
| #endif |
| |
| #ifndef STBI_NO_STDIO |
| |
| #if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8) |
| STBI_EXTERN __declspec(dllimport) int __stdcall MultiByteToWideChar(unsigned int cp, unsigned long flags, const char *str, int cbmb, wchar_t *widestr, int cchwide); |
| STBI_EXTERN __declspec(dllimport) int __stdcall WideCharToMultiByte(unsigned int cp, unsigned long flags, const wchar_t *widestr, int cchwide, char *str, int cbmb, const char *defchar, int *used_default); |
| #endif |
| |
| #if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8) |
| STBIDEF int stbi_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input) |
| { |
| return WideCharToMultiByte(65001 /* UTF8 */, 0, input, -1, buffer, bufferlen, NULL, NULL); |
| } |
| #endif |
| |
| static FILE *stbi__fopen(char const *filename, char const *mode) |
| { |
| FILE *f; |
| #if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8) |
| wchar_t wMode[64]; |
| wchar_t wFilename[1024]; |
| if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename))) |
| return 0; |
| |
| if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode))) |
| return 0; |
| |
| #if _MSC_VER >= 1400 |
| if (0 != _wfopen_s(&f, wFilename, wMode)) |
| f = 0; |
| #else |
| f = _wfopen(wFilename, wMode); |
| #endif |
| |
| #elif defined(_MSC_VER) && _MSC_VER >= 1400 |
| if (0 != fopen_s(&f, filename, mode)) |
| f=0; |
| #else |
| f = fopen(filename, mode); |
| #endif |
| return f; |
| } |
| |
| |
| STBIDEF stbi_uc *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp) |
| { |
| FILE *f = stbi__fopen(filename, "rb"); |
| unsigned char *result; |
| if (!f) return stbi__errpuc("can't fopen", "Unable to open file"); |
| result = stbi_load_from_file(f,x,y,comp,req_comp); |
| fclose(f); |
| return result; |
| } |
| |
| STBIDEF stbi_uc *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) |
| { |
| unsigned char *result; |
| stbi__context s; |
| stbi__start_file(&s,f); |
| result = stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp); |
| if (result) { |
| // need to 'unget' all the characters in the IO buffer |
| fseek(f, - (int) (s.img_buffer_end - s.img_buffer), SEEK_CUR); |
| } |
| return result; |
| } |
| |
| STBIDEF stbi__uint16 *stbi_load_from_file_16(FILE *f, int *x, int *y, int *comp, int req_comp) |
| { |
| stbi__uint16 *result; |
| stbi__context s; |
| stbi__start_file(&s,f); |
| result = stbi__load_and_postprocess_16bit(&s,x,y,comp,req_comp); |
| if (result) { |
| // need to 'unget' all the characters in the IO buffer |
| fseek(f, - (int) (s.img_buffer_end - s.img_buffer), SEEK_CUR); |
| } |
| return result; |
| } |
| |
| STBIDEF stbi_us *stbi_load_16(char const *filename, int *x, int *y, int *comp, int req_comp) |
| { |
| FILE *f = stbi__fopen(filename, "rb"); |
| stbi__uint16 *result; |
| if (!f) return (stbi_us *) stbi__errpuc("can't fopen", "Unable to open file"); |
| result = stbi_load_from_file_16(f,x,y,comp,req_comp); |
| fclose(f); |
| return result; |
| } |
| |
| |
| #endif //!STBI_NO_STDIO |
| |
| STBIDEF stbi_us *stbi_load_16_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels) |
| { |
| stbi__context s; |
| stbi__start_mem(&s,buffer,len); |
| return stbi__load_and_postprocess_16bit(&s,x,y,channels_in_file,desired_channels); |
| } |
| |
| STBIDEF stbi_us *stbi_load_16_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *channels_in_file, int desired_channels) |
| { |
| stbi__context s; |
| stbi__start_callbacks(&s, (stbi_io_callbacks *)clbk, user); |
| return stbi__load_and_postprocess_16bit(&s,x,y,channels_in_file,desired_channels); |
| } |
| |
| STBIDEF stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) |
| { |
| stbi__context s; |
| stbi__start_mem(&s,buffer,len); |
| return stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp); |
| } |
| |
| STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp) |
| { |
| stbi__context s; |
| stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user); |
| return stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp); |
| } |
| |
| #ifndef STBI_NO_GIF |
| STBIDEF stbi_uc *stbi_load_gif_from_memory(stbi_uc const *buffer, int len, int **delays, int *x, int *y, int *z, int *comp, int req_comp) |
| { |
| unsigned char *result; |
| stbi__context s; |
| stbi__start_mem(&s,buffer,len); |
| |
| result = (unsigned char*) stbi__load_gif_main(&s, delays, x, y, z, comp, req_comp); |
| if (stbi__vertically_flip_on_load) { |
| stbi__vertical_flip_slices( result, *x, *y, *z, *comp ); |
| } |
| |
| return result; |
| } |
| #endif |
| |
| #ifndef STBI_NO_LINEAR |
| static float *stbi__loadf_main(stbi__context *s, int *x, int *y, int *comp, int req_comp) |
| { |
| unsigned char *data; |
| #ifndef STBI_NO_HDR |
| if (stbi__hdr_test(s)) { |
| stbi__result_info ri; |
| float *hdr_data = stbi__hdr_load(s,x,y,comp,req_comp, &ri); |
| if (hdr_data) |
| stbi__float_postprocess(hdr_data,x,y,comp,req_comp); |
| return hdr_data; |
| } |
| #endif |
| data = stbi__load_and_postprocess_8bit(s, x, y, comp, req_comp); |
| if (data) |
| return stbi__ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp); |
| return stbi__errpf("unknown image type", "Image not of any known type, or corrupt"); |
| } |
| |
| STBIDEF float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp) |
| { |
| stbi__context s; |
| stbi__start_mem(&s,buffer,len); |
| return stbi__loadf_main(&s,x,y,comp,req_comp); |
| } |
| |
| STBIDEF float *stbi_loadf_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp) |
| { |
| stbi__context s; |
| stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user); |
| return stbi__loadf_main(&s,x,y,comp,req_comp); |
| } |
| |
| #ifndef STBI_NO_STDIO |
| STBIDEF float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp) |
| { |
| float *result; |
| FILE *f = stbi__fopen(filename, "rb"); |
| if (!f) return stbi__errpf("can't fopen", "Unable to open file"); |
| result = stbi_loadf_from_file(f,x,y,comp,req_comp); |
| fclose(f); |
| return result; |
| } |
| |
| STBIDEF float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp) |
| { |
| stbi__context s; |
| stbi__start_file(&s,f); |
| return stbi__loadf_main(&s,x,y,comp,req_comp); |
| } |
| #endif // !STBI_NO_STDIO |
| |
| #endif // !STBI_NO_LINEAR |
| |
| // these is-hdr-or-not is defined independent of whether STBI_NO_LINEAR is |
| // defined, for API simplicity; if STBI_NO_LINEAR is defined, it always |
| // reports false! |
| |
| STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len) |
| { |
| #ifndef STBI_NO_HDR |
| stbi__context s; |
| stbi__start_mem(&s,buffer,len); |
| return stbi__hdr_test(&s); |
| #else |
| STBI_NOTUSED(buffer); |
| STBI_NOTUSED(len); |
| return 0; |
| #endif |
| } |
| |
| #ifndef STBI_NO_STDIO |
| STBIDEF int stbi_is_hdr (char const *filename) |
| { |
| FILE *f = stbi__fopen(filename, "rb"); |
| int result=0; |
| if (f) { |
| result = stbi_is_hdr_from_file(f); |
| fclose(f); |
| } |
| return result; |
| } |
| |
| STBIDEF int stbi_is_hdr_from_file(FILE *f) |
| { |
| #ifndef STBI_NO_HDR |
| long pos = ftell(f); |
| int res; |
| stbi__context s; |
| stbi__start_file(&s,f); |
| res = stbi__hdr_test(&s); |
| fseek(f, pos, SEEK_SET); |
| return res; |
| #else |
| STBI_NOTUSED(f); |
| return 0; |
| #endif |
| } |
| #endif // !STBI_NO_STDIO |
| |
| STBIDEF int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user) |
| { |
| #ifndef STBI_NO_HDR |
| stbi__context s; |
| stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user); |
| return stbi__hdr_test(&s); |
| #else |
| STBI_NOTUSED(clbk); |
| STBI_NOTUSED(user); |
| return 0; |
| #endif |
| } |
| |
| #ifndef STBI_NO_LINEAR |
| static float stbi__l2h_gamma=2.2f, stbi__l2h_scale=1.0f; |
| |
| STBIDEF void stbi_ldr_to_hdr_gamma(float gamma) { stbi__l2h_gamma = gamma; } |
| STBIDEF void stbi_ldr_to_hdr_scale(float scale) { stbi__l2h_scale = scale; } |
| #endif |
| |
| static float stbi__h2l_gamma_i=1.0f/2.2f, stbi__h2l_scale_i=1.0f; |
| |
| STBIDEF void stbi_hdr_to_ldr_gamma(float gamma) { stbi__h2l_gamma_i = 1/gamma; } |
| STBIDEF void stbi_hdr_to_ldr_scale(float scale) { stbi__h2l_scale_i = 1/scale; } |
| |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| // |
| // Common code used by all image loaders |
| // |
| |
| enum |
| { |
| STBI__SCAN_load=0, |
| STBI__SCAN_type, |
| STBI__SCAN_header |
| }; |
| |
| static void stbi__refill_buffer(stbi__context *s) |
| { |
| int n = (s->io.read)(s->io_user_data,(char*)s->buffer_start,s->buflen); |
| if (n == 0) { |
| // at end of file, treat same as if from memory, but need to handle case |
| // where s->img_buffer isn't pointing to safe memory, e.g. 0-byte file |
| s->read_from_callbacks = 0; |
| s->img_buffer = s->buffer_start; |
| s->img_buffer_end = s->buffer_start+1; |
| *s->img_buffer = 0; |
| } else { |
| s->img_buffer = s->buffer_start; |
| s->img_buffer_end = s->buffer_start + n; |
| } |
| } |
| |
| stbi_inline static stbi_uc stbi__get8(stbi__context *s) |
| { |
| if (s->img_buffer < s->img_buffer_end) |
| return *s->img_buffer++; |
| if (s->read_from_callbacks) { |
| stbi__refill_buffer(s); |
| return *s->img_buffer++; |
| } |
| return 0; |
| } |
| |
| stbi_inline static int stbi__at_eof(stbi__context *s) |
| { |
| if (s->io.read) { |
| if (!(s->io.eof)(s->io_user_data)) return 0; |
| // if feof() is true, check if buffer = end |
| // special case: we've only got the special 0 character at the end |
| if (s->read_from_callbacks == 0) return 1; |
| } |
| |
| return s->img_buffer >= s->img_buffer_end; |
| } |
| |
| static void stbi__skip(stbi__context *s, int n) |
| { |
| if (n < 0) { |
| s->img_buffer = s->img_buffer_end; |
| return; |
| } |
| if (s->io.read) { |
| int blen = (int) (s->img_buffer_end - s->img_buffer); |
| if (blen < n) { |
| s->img_buffer = s->img_buffer_end; |
| (s->io.skip)(s->io_user_data, n - blen); |
| return; |
| } |
| } |
| s->img_buffer += n; |
| } |
| |
| static int stbi__getn(stbi__context *s, stbi_uc *buffer, int n) |
| { |
| if (s->io.read) { |
| int blen = (int) (s->img_buffer_end - s->img_buffer); |
| if (blen < n) { |
| int res, count; |
| |
| memcpy(buffer, s->img_buffer, blen); |
| |
| count = (s->io.read)(s->io_user_data, (char*) buffer + blen, n - blen); |
| res = (count == (n-blen)); |
| s->img_buffer = s->img_buffer_end; |
| return res; |
| } |
| } |
| |
| if (s->img_buffer+n <= s->img_buffer_end) { |
| memcpy(buffer, s->img_buffer, n); |
| s->img_buffer += n; |
| return 1; |
| } else |
| return 0; |
| } |
| |
| static int stbi__get16be(stbi__context *s) |
| { |
| int z = stbi__get8(s); |
| return (z << 8) + stbi__get8(s); |
| } |
| |
| static stbi__uint32 stbi__get32be(stbi__context *s) |
| { |
| stbi__uint32 z = stbi__get16be(s); |
| return (z << 16) + stbi__get16be(s); |
| } |
| |
| #if defined(STBI_NO_BMP) && defined(STBI_NO_TGA) && defined(STBI_NO_GIF) |
| // nothing |
| #else |
| static int stbi__get16le(stbi__context *s) |
| { |
| int z = stbi__get8(s); |
| return z + (stbi__get8(s) << 8); |
| } |
| #endif |
| |
| #ifndef STBI_NO_BMP |
| static stbi__uint32 stbi__get32le(stbi__context *s) |
| { |
| stbi__uint32 z = stbi__get16le(s); |
| return z + (stbi__get16le(s) << 16); |
| } |
| #endif |
| |
| #define STBI__BYTECAST(x) ((stbi_uc) ((x) & 255)) // truncate int to byte without warnings |
| |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| // |
| // generic converter from built-in img_n to req_comp |
| // individual types do this automatically as much as possible (e.g. jpeg |
| // does all cases internally since it needs to colorspace convert anyway, |
| // and it never has alpha, so very few cases ). png can automatically |
| // interleave an alpha=255 channel, but falls back to this for other cases |
| // |
| // assume data buffer is malloced, so malloc a new one and free that one |
| // only failure mode is malloc failing |
| |
| static stbi_uc stbi__compute_y(int r, int g, int b) |
| { |
| return (stbi_uc) (((r*77) + (g*150) + (29*b)) >> 8); |
| } |
| |
| static unsigned char *stbi__convert_format(unsigned char *data, int img_n, int req_comp, unsigned int x, unsigned int y) |
| { |
| int i,j; |
| unsigned char *good; |
| |
| if (req_comp == img_n) return data; |
| STBI_ASSERT(req_comp >= 1 && req_comp <= 4); |
| |
| good = (unsigned char *) stbi__malloc_mad3(req_comp, x, y, 0); |
| if (good == NULL) { |
| STBI_FREE(data); |
| return stbi__errpuc("outofmem", "Out of memory"); |
| } |
| |
| for (j=0; j < (int) y; ++j) { |
| unsigned char *src = data + j * x * img_n ; |
| unsigned char *dest = good + j * x * req_comp; |
| |
| #define STBI__COMBO(a,b) ((a)*8+(b)) |
| #define STBI__CASE(a,b) case STBI__COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b) |
| // convert source image with img_n components to one with req_comp components; |
| // avoid switch per pixel, so use switch per scanline and massive macros |
| switch (STBI__COMBO(img_n, req_comp)) { |
| STBI__CASE(1,2) { dest[0]=src[0]; dest[1]=255; } break; |
| STBI__CASE(1,3) { dest[0]=dest[1]=dest[2]=src[0]; } break; |
| STBI__CASE(1,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=255; } break; |
| STBI__CASE(2,1) { dest[0]=src[0]; } break; |
| STBI__CASE(2,3) { dest[0]=dest[1]=dest[2]=src[0]; } break; |
| STBI__CASE(2,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=src[1]; } break; |
| STBI__CASE(3,4) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2];dest[3]=255; } break; |
| STBI__CASE(3,1) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); } break; |
| STBI__CASE(3,2) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); dest[1] = 255; } break; |
| STBI__CASE(4,1) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); } break; |
| STBI__CASE(4,2) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); dest[1] = src[3]; } break; |
| STBI__CASE(4,3) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2]; } break; |
| default: STBI_ASSERT(0); |
| } |
| #undef STBI__CASE |
| } |
| |
| STBI_FREE(data); |
| return good; |
| } |
| |
| static stbi__uint16 stbi__compute_y_16(int r, int g, int b) |
| { |
| return (stbi__uint16) (((r*77) + (g*150) + (29*b)) >> 8); |
| } |
| |
| static stbi__uint16 *stbi__convert_format16(stbi__uint16 *data, int img_n, int req_comp, unsigned int x, unsigned int y) |
| { |
| int i,j; |
| stbi__uint16 *good; |
| |
| if (req_comp == img_n) return data; |
| STBI_ASSERT(req_comp >= 1 && req_comp <= 4); |
| |
| good = (stbi__uint16 *) stbi__malloc(req_comp * x * y * 2); |
| if (good == NULL) { |
| STBI_FREE(data); |
| return (stbi__uint16 *) stbi__errpuc("outofmem", "Out of memory"); |
| } |
| |
| for (j=0; j < (int) y; ++j) { |
| stbi__uint16 *src = data + j * x * img_n ; |
| stbi__uint16 *dest = good + j * x * req_comp; |
| |
| #define STBI__COMBO(a,b) ((a)*8+(b)) |
| #define STBI__CASE(a,b) case STBI__COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b) |
| // convert source image with img_n components to one with req_comp components; |
| // avoid switch per pixel, so use switch per scanline and massive macros |
| switch (STBI__COMBO(img_n, req_comp)) { |
| STBI__CASE(1,2) { dest[0]=src[0]; dest[1]=0xffff; } break; |
| STBI__CASE(1,3) { dest[0]=dest[1]=dest[2]=src[0]; } break; |
| STBI__CASE(1,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=0xffff; } break; |
| STBI__CASE(2,1) { dest[0]=src[0]; } break; |
| STBI__CASE(2,3) { dest[0]=dest[1]=dest[2]=src[0]; } break; |
| STBI__CASE(2,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=src[1]; } break; |
| STBI__CASE(3,4) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2];dest[3]=0xffff; } break; |
| STBI__CASE(3,1) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); } break; |
| STBI__CASE(3,2) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); dest[1] = 0xffff; } break; |
| STBI__CASE(4,1) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); } break; |
| STBI__CASE(4,2) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); dest[1] = src[3]; } break; |
| STBI__CASE(4,3) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2]; } break; |
| default: STBI_ASSERT(0); |
| } |
| #undef STBI__CASE |
| } |
| |
| STBI_FREE(data); |
| return good; |
| } |
| |
| #ifndef STBI_NO_LINEAR |
| static float *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp) |
| { |
| int i,k,n; |
| float *output; |
| if (!data) return NULL; |
| output = (float *) stbi__malloc_mad4(x, y, comp, sizeof(float), 0); |
| if (output == NULL) { STBI_FREE(data); return stbi__errpf("outofmem", "Out of memory"); } |
| // compute number of non-alpha components |
| if (comp & 1) n = comp; else n = comp-1; |
| for (i=0; i < x*y; ++i) { |
| for (k=0; k < n; ++k) { |
| output[i*comp + k] = (float) (pow(data[i*comp+k]/255.0f, stbi__l2h_gamma) * stbi__l2h_scale); |
| } |
| } |
| if (n < comp) { |
| for (i=0; i < x*y; ++i) { |
| output[i*comp + n] = data[i*comp + n]/255.0f; |
| } |
| } |
| STBI_FREE(data); |
| return output; |
| } |
| #endif |
| |
| #ifndef STBI_NO_HDR |
| #define stbi__float2int(x) ((int) (x)) |
| static stbi_uc *stbi__hdr_to_ldr(float *data, int x, int y, int comp) |
| { |
| int i,k,n; |
| stbi_uc *output; |
| if (!data) return NULL; |
| output = (stbi_uc *) stbi__malloc_mad3(x, y, comp, 0); |
| if (output == NULL) { STBI_FREE(data); return stbi__errpuc("outofmem", "Out of memory"); } |
| // compute number of non-alpha components |
| if (comp & 1) n = comp; else n = comp-1; |
| for (i=0; i < x*y; ++i) { |
| for (k=0; k < n; ++k) { |
| float z = (float) pow(data[i*comp+k]*stbi__h2l_scale_i, stbi__h2l_gamma_i) * 255 + 0.5f; |
| if (z < 0) z = 0; |
| if (z > 255) z = 255; |
| output[i*comp + k] = (stbi_uc) stbi__float2int(z); |
| } |
| if (k < comp) { |
| float z = data[i*comp+k] * 255 + 0.5f; |
| if (z < 0) z = 0; |
| if (z > 255) z = 255; |
| output[i*comp + k] = (stbi_uc) stbi__float2int(z); |
| } |
| } |
| STBI_FREE(data); |
| return output; |
| } |
| #endif |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| // |
| // "baseline" JPEG/JFIF decoder |
| // |
| // simple implementation |
| // - doesn't support delayed output of y-dimension |
| // - simple interface (only one output format: 8-bit interleaved RGB) |
| // - doesn't try to recover corrupt jpegs |
| // - doesn't allow partial loading, loading multiple at once |
| // - still fast on x86 (copying globals into locals doesn't help x86) |
| // - allocates lots of intermediate memory (full size of all components) |
| // - non-interleaved case requires this anyway |
| // - allows good upsampling (see next) |
| // high-quality |
| // - upsampled channels are bilinearly interpolated, even across blocks |
| // - quality integer IDCT derived from IJG's 'slow' |
| // performance |
| // - fast huffman; reasonable integer IDCT |
| // - some SIMD kernels for common paths on targets with SSE2/NEON |
| // - uses a lot of intermediate memory, could cache poorly |
| |
| #ifndef STBI_NO_JPEG |
| |
| // huffman decoding acceleration |
| #define FAST_BITS 9 // larger handles more cases; smaller stomps less cache |
| |
| typedef struct |
| { |
| stbi_uc fast[1 << FAST_BITS]; |
| // weirdly, repacking this into AoS is a 10% speed loss, instead of a win |
| stbi__uint16 code[256]; |
| stbi_uc values[256]; |
| stbi_uc size[257]; |
| unsigned int maxcode[18]; |
| int delta[17]; // old 'firstsymbol' - old 'firstcode' |
| } stbi__huffman; |
| |
| typedef struct |
| { |
| stbi__context *s; |
| stbi__huffman huff_dc[4]; |
| stbi__huffman huff_ac[4]; |
| stbi__uint16 dequant[4][64]; |
| stbi__int16 fast_ac[4][1 << FAST_BITS]; |
| |
| // sizes for components, interleaved MCUs |
| int img_h_max, img_v_max; |
| int img_mcu_x, img_mcu_y; |
| int img_mcu_w, img_mcu_h; |
| |
| // definition of jpeg image component |
| struct |
| { |
| int id; |
| int h,v; |
| int tq; |
| int hd,ha; |
| int dc_pred; |
| |
| int x,y,w2,h2; |
| stbi_uc *data; |
| void *raw_data, *raw_coeff; |
| stbi_uc *linebuf; |
| short *coeff; // progressive only |
| int coeff_w, coeff_h; // number of 8x8 coefficient blocks |
| } img_comp[4]; |
| |
| stbi__uint32 code_buffer; // jpeg entropy-coded buffer |
| int code_bits; // number of valid bits |
| unsigned char marker; // marker seen while filling entropy buffer |
| int nomore; // flag if we saw a marker so must stop |
| |
| int progressive; |
| int spec_start; |
| int spec_end; |
| int succ_high; |
| int succ_low; |
| int eob_run; |
| int jfif; |
| int app14_color_transform; // Adobe APP14 tag |
| int rgb; |
| |
| int scan_n, order[4]; |
| int restart_interval, todo; |
| |
| // kernels |
| void (*idct_block_kernel)(stbi_uc *out, int out_stride, short data[64]); |
| void (*YCbCr_to_RGB_kernel)(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step); |
| stbi_uc *(*resample_row_hv_2_kernel)(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs); |
| } stbi__jpeg; |
| |
| static int stbi__build_huffman(stbi__huffman *h, int *count) |
| { |
| int i,j,k=0; |
| unsigned int code; |
| // build size list for each symbol (from JPEG spec) |
| for (i=0; i < 16; ++i) |
| for (j=0; j < count[i]; ++j) |
| h->size[k++] = (stbi_uc) (i+1); |
| h->size[k] = 0; |
| |
| // compute actual symbols (from jpeg spec) |
| code = 0; |
| k = 0; |
| for(j=1; j <= 16; ++j) { |
| // compute delta to add to code to compute symbol id |
| h->delta[j] = k - code; |
| if (h->size[k] == j) { |
| while (h->size[k] == j) |
| h->code[k++] = (stbi__uint16) (code++); |
| if (code-1 >= (1u << j)) return stbi__err("bad code lengths","Corrupt JPEG"); |
| } |
| // compute largest code + 1 for this size, preshifted as needed later |
| h->maxcode[j] = code << (16-j); |
| code <<= 1; |
| } |
| h->maxcode[j] = 0xffffffff; |
| |
| // build non-spec acceleration table; 255 is flag for not-accelerated |
| memset(h->fast, 255, 1 << FAST_BITS); |
| for (i=0; i < k; ++i) { |
| int s = h->size[i]; |
| if (s <= FAST_BITS) { |
| int c = h->code[i] << (FAST_BITS-s); |
| int m = 1 << (FAST_BITS-s); |
| for (j=0; j < m; ++j) { |
| h->fast[c+j] = (stbi_uc) i; |
| } |
| } |
| } |
| return 1; |
| } |
| |
| // build a table that decodes both magnitude and value of small ACs in |
| // one go. |
| static void stbi__build_fast_ac(stbi__int16 *fast_ac, stbi__huffman *h) |
| { |
| int i; |
| for (i=0; i < (1 << FAST_BITS); ++i) { |
| stbi_uc fast = h->fast[i]; |
| fast_ac[i] = 0; |
| if (fast < 255) { |
| int rs = h->values[fast]; |
| int run = (rs >> 4) & 15; |
| int magbits = rs & 15; |
| int len = h->size[fast]; |
| |
| if (magbits && len + magbits <= FAST_BITS) { |
| // magnitude code followed by receive_extend code |
| int k = ((i << len) & ((1 << FAST_BITS) - 1)) >> (FAST_BITS - magbits); |
| int m = 1 << (magbits - 1); |
| if (k < m) k += (~0U << magbits) + 1; |
| // if the result is small enough, we can fit it in fast_ac table |
| if (k >= -128 && k <= 127) |
| fast_ac[i] = (stbi__int16) ((k * 256) + (run * 16) + (len + magbits)); |
| } |
| } |
| } |
| } |
| |
| static void stbi__grow_buffer_unsafe(stbi__jpeg *j) |
| { |
| do { |
| unsigned int b = j->nomore ? 0 : stbi__get8(j->s); |
| if (b == 0xff) { |
| int c = stbi__get8(j->s); |
| while (c == 0xff) c = stbi__get8(j->s); // consume fill bytes |
| if (c != 0) { |
| j->marker = (unsigned char) c; |
| j->nomore = 1; |
| return; |
| } |
| } |
| j->code_buffer |= b << (24 - j->code_bits); |
| j->code_bits += 8; |
| } while (j->code_bits <= 24); |
| } |
| |
| // (1 << n) - 1 |
| static const stbi__uint32 stbi__bmask[17]={0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535}; |
| |
| // decode a jpeg huffman value from the bitstream |
| stbi_inline static int stbi__jpeg_huff_decode(stbi__jpeg *j, stbi__huffman *h) |
| { |
| unsigned int temp; |
| int c,k; |
| |
| if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); |
| |
| // look at the top FAST_BITS and determine what symbol ID it is, |
| // if the code is <= FAST_BITS |
| c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1); |
| k = h->fast[c]; |
| if (k < 255) { |
| int s = h->size[k]; |
| if (s > j->code_bits) |
| return -1; |
| j->code_buffer <<= s; |
| j->code_bits -= s; |
| return h->values[k]; |
| } |
| |
| // naive test is to shift the code_buffer down so k bits are |
| // valid, then test against maxcode. To speed this up, we've |
| // preshifted maxcode left so that it has (16-k) 0s at the |
| // end; in other words, regardless of the number of bits, it |
| // wants to be compared against something shifted to have 16; |
| // that way we don't need to shift inside the loop. |
| temp = j->code_buffer >> 16; |
| for (k=FAST_BITS+1 ; ; ++k) |
| if (temp < h->maxcode[k]) |
| break; |
| if (k == 17) { |
| // error! code not found |
| j->code_bits -= 16; |
| return -1; |
| } |
| |
| if (k > j->code_bits) |
| return -1; |
| |
| // convert the huffman code to the symbol id |
| c = ((j->code_buffer >> (32 - k)) & stbi__bmask[k]) + h->delta[k]; |
| STBI_ASSERT((((j->code_buffer) >> (32 - h->size[c])) & stbi__bmask[h->size[c]]) == h->code[c]); |
| |
| // convert the id to a symbol |
| j->code_bits -= k; |
| j->code_buffer <<= k; |
| return h->values[c]; |
| } |
| |
| // bias[n] = (-1<<n) + 1 |
| static const int stbi__jbias[16] = {0,-1,-3,-7,-15,-31,-63,-127,-255,-511,-1023,-2047,-4095,-8191,-16383,-32767}; |
| |
| // combined JPEG 'receive' and JPEG 'extend', since baseline |
| // always extends everything it receives. |
| stbi_inline static int stbi__extend_receive(stbi__jpeg *j, int n) |
| { |
| unsigned int k; |
| int sgn; |
| if (j->code_bits < n) stbi__grow_buffer_unsafe(j); |
| |
| sgn = (stbi__int32)j->code_buffer >> 31; // sign bit is always in MSB |
| k = stbi_lrot(j->code_buffer, n); |
| STBI_ASSERT(n >= 0 && n < (int) (sizeof(stbi__bmask)/sizeof(*stbi__bmask))); |
| j->code_buffer = k & ~stbi__bmask[n]; |
| k &= stbi__bmask[n]; |
| j->code_bits -= n; |
| return k + (stbi__jbias[n] & ~sgn); |
| } |
| |
| // get some unsigned bits |
| stbi_inline static int stbi__jpeg_get_bits(stbi__jpeg *j, int n) |
| { |
| unsigned int k; |
| if (j->code_bits < n) stbi__grow_buffer_unsafe(j); |
| k = stbi_lrot(j->code_buffer, n); |
| j->code_buffer = k & ~stbi__bmask[n]; |
| k &= stbi__bmask[n]; |
| j->code_bits -= n; |
| return k; |
| } |
| |
| stbi_inline static int stbi__jpeg_get_bit(stbi__jpeg *j) |
| { |
| unsigned int k; |
| if (j->code_bits < 1) stbi__grow_buffer_unsafe(j); |
| k = j->code_buffer; |
| j->code_buffer <<= 1; |
| --j->code_bits; |
| return k & 0x80000000; |
| } |
| |
| // given a value that's at position X in the zigzag stream, |
| // where does it appear in the 8x8 matrix coded as row-major? |
| static const stbi_uc stbi__jpeg_dezigzag[64+15] = |
| { |
| 0, 1, 8, 16, 9, 2, 3, 10, |
| 17, 24, 32, 25, 18, 11, 4, 5, |
| 12, 19, 26, 33, 40, 48, 41, 34, |
| 27, 20, 13, 6, 7, 14, 21, 28, |
| 35, 42, 49, 56, 57, 50, 43, 36, |
| 29, 22, 15, 23, 30, 37, 44, 51, |
| 58, 59, 52, 45, 38, 31, 39, 46, |
| 53, 60, 61, 54, 47, 55, 62, 63, |
| // let corrupt input sample past end |
| 63, 63, 63, 63, 63, 63, 63, 63, |
| 63, 63, 63, 63, 63, 63, 63 |
| }; |
| |
| // decode one 64-entry block-- |
| static int stbi__jpeg_decode_block(stbi__jpeg *j, short data[64], stbi__huffman *hdc, stbi__huffman *hac, stbi__int16 *fac, int b, stbi__uint16 *dequant) |
| { |
| int diff,dc,k; |
| int t; |
| |
| if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); |
| t = stbi__jpeg_huff_decode(j, hdc); |
| if (t < 0) return stbi__err("bad huffman code","Corrupt JPEG"); |
| |
| // 0 all the ac values now so we can do it 32-bits at a time |
| memset(data,0,64*sizeof(data[0])); |
| |
| diff = t ? stbi__extend_receive(j, t) : 0; |
| dc = j->img_comp[b].dc_pred + diff; |
| j->img_comp[b].dc_pred = dc; |
| data[0] = (short) (dc * dequant[0]); |
| |
| // decode AC components, see JPEG spec |
| k = 1; |
| do { |
| unsigned int zig; |
| int c,r,s; |
| if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); |
| c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1); |
| r = fac[c]; |
| if (r) { // fast-AC path |
| k += (r >> 4) & 15; // run |
| s = r & 15; // combined length |
| j->code_buffer <<= s; |
| j->code_bits -= s; |
| // decode into unzigzag'd location |
| zig = stbi__jpeg_dezigzag[k++]; |
| data[zig] = (short) ((r >> 8) * dequant[zig]); |
| } else { |
| int rs = stbi__jpeg_huff_decode(j, hac); |
| if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG"); |
| s = rs & 15; |
| r = rs >> 4; |
| if (s == 0) { |
| if (rs != 0xf0) break; // end block |
| k += 16; |
| } else { |
| k += r; |
| // decode into unzigzag'd location |
| zig = stbi__jpeg_dezigzag[k++]; |
| data[zig] = (short) (stbi__extend_receive(j,s) * dequant[zig]); |
| } |
| } |
| } while (k < 64); |
| return 1; |
| } |
| |
| static int stbi__jpeg_decode_block_prog_dc(stbi__jpeg *j, short data[64], stbi__huffman *hdc, int b) |
| { |
| int diff,dc; |
| int t; |
| if (j->spec_end != 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG"); |
| |
| if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); |
| |
| if (j->succ_high == 0) { |
| // first scan for DC coefficient, must be first |
| memset(data,0,64*sizeof(data[0])); // 0 all the ac values now |
| t = stbi__jpeg_huff_decode(j, hdc); |
| diff = t ? stbi__extend_receive(j, t) : 0; |
| |
| dc = j->img_comp[b].dc_pred + diff; |
| j->img_comp[b].dc_pred = dc; |
| data[0] = (short) (dc << j->succ_low); |
| } else { |
| // refinement scan for DC coefficient |
| if (stbi__jpeg_get_bit(j)) |
| data[0] += (short) (1 << j->succ_low); |
| } |
| return 1; |
| } |
| |
| // @OPTIMIZE: store non-zigzagged during the decode passes, |
| // and only de-zigzag when dequantizing |
| static int stbi__jpeg_decode_block_prog_ac(stbi__jpeg *j, short data[64], stbi__huffman *hac, stbi__int16 *fac) |
| { |
| int k; |
| if (j->spec_start == 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG"); |
| |
| if (j->succ_high == 0) { |
| int shift = j->succ_low; |
| |
| if (j->eob_run) { |
| --j->eob_run; |
| return 1; |
| } |
| |
| k = j->spec_start; |
| do { |
| unsigned int zig; |
| int c,r,s; |
| if (j->code_bits < 16) stbi__grow_buffer_unsafe(j); |
| c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1); |
| r = fac[c]; |
| if (r) { // fast-AC path |
| k += (r >> 4) & 15; // run |
| s = r & 15; // combined length |
| j->code_buffer <<= s; |
| j->code_bits -= s; |
| zig = stbi__jpeg_dezigzag[k++]; |
| data[zig] = (short) ((r >> 8) << shift); |
| } else { |
| int rs = stbi__jpeg_huff_decode(j, hac); |
| if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG"); |
| s = rs & 15; |
| r = rs >> 4; |
| if (s == 0) { |
| if (r < 15) { |
| j->eob_run = (1 << r); |
| if (r) |
| j->eob_run += stbi__jpeg_get_bits(j, r); |
| --j->eob_run; |
| break; |
| } |
| k += 16; |
| } else { |
| k += r; |
| zig = stbi__jpeg_dezigzag[k++]; |
| data[zig] = (short) (stbi__extend_receive(j,s) << shift); |
| } |
| } |
| } while (k <= j->spec_end); |
| } else { |
| // refinement scan for these AC coefficients |
| |
| short bit = (short) (1 << j->succ_low); |
| |
| if (j->eob_run) { |
| --j->eob_run; |
| for (k = j->spec_start; k <= j->spec_end; ++k) { |
| short *p = &data[stbi__jpeg_dezigzag[k]]; |
| if (*p != 0) |
| if (stbi__jpeg_get_bit(j)) |
| if ((*p & bit)==0) { |
| if (*p > 0) |
| *p += bit; |
| else |
| *p -= bit; |
| } |
| } |
| } else { |
| k = j->spec_start; |
| do { |
| int r,s; |
| int rs = stbi__jpeg_huff_decode(j, hac); // @OPTIMIZE see if we can use the fast path here, advance-by-r is so slow, eh |
| if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG"); |
| s = rs & 15; |
| r = rs >> 4; |
| if (s == 0) { |
| if (r < 15) { |
| j->eob_run = (1 << r) - 1; |
| if (r) |
| j->eob_run += stbi__jpeg_get_bits(j, r); |
| r = 64; // force end of block |
| } else { |
| // r=15 s=0 should write 16 0s, so we just do |
| // a run of 15 0s and then write s (which is 0), |
| // so we don't have to do anything special here |
| } |
| } else { |
| if (s != 1) return stbi__err("bad huffman code", "Corrupt JPEG"); |
| // sign bit |
| if (stbi__jpeg_get_bit(j)) |
| s = bit; |
| else |
| s = -bit; |
| } |
| |
| // advance by r |
| while (k <= j->spec_end) { |
| short *p = &data[stbi__jpeg_dezigzag[k++]]; |
| if (*p != 0) { |
| if (stbi__jpeg_get_bit(j)) |
| if ((*p & bit)==0) { |
| if (*p > 0) |
| *p += bit; |
| else |
| *p -= bit; |
| } |
| } else { |
| if (r == 0) { |
| *p = (short) s; |
| break; |
| } |
| --r; |
| } |
| } |
| } while (k <= j->spec_end); |
| } |
| } |
| return 1; |
| } |
| |
| // take a -128..127 value and stbi__clamp it and convert to 0..255 |
| stbi_inline static stbi_uc stbi__clamp(int x) |
| { |
| // trick to use a single test to catch both cases |
| if ((unsigned int) x > 255) { |
| if (x < 0) return 0; |
| if (x > 255) return 255; |
| } |
| return (stbi_uc) x; |
| } |
| |
| #define stbi__f2f(x) ((int) (((x) * 4096 + 0.5))) |
| #define stbi__fsh(x) ((x) * 4096) |
| |
| // derived from jidctint -- DCT_ISLOW |
| #define STBI__IDCT_1D(s0,s1,s2,s3,s4,s5,s6,s7) \ |
| int t0,t1,t2,t3,p1,p2,p3,p4,p5,x0,x1,x2,x3; \ |
| p2 = s2; \ |
| p3 = s6; \ |
| p1 = (p2+p3) * stbi__f2f(0.5411961f); \ |
| t2 = p1 + p3*stbi__f2f(-1.847759065f); \ |
| t3 = p1 + p2*stbi__f2f( 0.765366865f); \ |
| p2 = s0; \ |
| p3 = s4; \ |
| t0 = stbi__fsh(p2+p3); \ |
| t1 = stbi__fsh(p2-p3); \ |
| x0 = t0+t3; \ |
| x3 = t0-t3; \ |
| x1 = t1+t2; \ |
| x2 = t1-t2; \ |
| t0 = s7; \ |
| t1 = s5; \ |
| t2 = s3; \ |
| t3 = s1; \ |
| p3 = t0+t2; \ |
| p4 = t1+t3; \ |
| p1 = t0+t3; \ |
| p2 = t1+t2; \ |
| p5 = (p3+p4)*stbi__f2f( 1.175875602f); \ |
| t0 = t0*stbi__f2f( 0.298631336f); \ |
| t1 = t1*stbi__f2f( 2.053119869f); \ |
| t2 = t2*stbi__f2f( 3.072711026f); \ |
| t3 = t3*stbi__f2f( 1.501321110f); \ |
| p1 = p5 + p1*stbi__f2f(-0.899976223f); \ |
| p2 = p5 + p2*stbi__f2f(-2.562915447f); \ |
| p3 = p3*stbi__f2f(-1.961570560f); \ |
| p4 = p4*stbi__f2f(-0.390180644f); \ |
| t3 += p1+p4; \ |
| t2 += p2+p3; \ |
| t1 += p2+p4; \ |
| t0 += p1+p3; |
| |
| static void stbi__idct_block(stbi_uc *out, int out_stride, short data[64]) |
| { |
| int i,val[64],*v=val; |
| stbi_uc *o; |
| short *d = data; |
| |
| // columns |
| for (i=0; i < 8; ++i,++d, ++v) { |
| // if all zeroes, shortcut -- this avoids dequantizing 0s and IDCTing |
| if (d[ 8]==0 && d[16]==0 && d[24]==0 && d[32]==0 |
| && d[40]==0 && d[48]==0 && d[56]==0) { |
| // no shortcut 0 seconds |
| // (1|2|3|4|5|6|7)==0 0 seconds |
| // all separate -0.047 seconds |
| // 1 && 2|3 && 4|5 && 6|7: -0.047 seconds |
| int dcterm = d[0]*4; |
| v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm; |
| } else { |
| STBI__IDCT_1D(d[ 0],d[ 8],d[16],d[24],d[32],d[40],d[48],d[56]) |
| // constants scaled things up by 1<<12; let's bring them back |
| // down, but keep 2 extra bits of precision |
| x0 += 512; x1 += 512; x2 += 512; x3 += 512; |
| v[ 0] = (x0+t3) >> 10; |
| v[56] = (x0-t3) >> 10; |
| v[ 8] = (x1+t2) >> 10; |
| v[48] = (x1-t2) >> 10; |
| v[16] = (x2+t1) >> 10; |
| v[40] = (x2-t1) >> 10; |
| v[24] = (x3+t0) >> 10; |
| v[32] = (x3-t0) >> 10; |
| } |
| } |
| |
| for (i=0, v=val, o=out; i < 8; ++i,v+=8,o+=out_stride) { |
| // no fast case since the first 1D IDCT spread components out |
| STBI__IDCT_1D(v[0],v[1],v[2],v[3],v[4],v[5],v[6],v[7]) |
| // constants scaled things up by 1<<12, plus we had 1<<2 from first |
| // loop, plus horizontal and vertical each scale by sqrt(8) so together |
| // we've got an extra 1<<3, so 1<<17 total we need to remove. |
| // so we want to round that, which means adding 0.5 * 1<<17, |
| // aka 65536. Also, we'll end up with -128 to 127 that we want |
| // to encode as 0..255 by adding 128, so we'll add that before the shift |
| x0 += 65536 + (128<<17); |
| x1 += 65536 + (128<<17); |
| x2 += 65536 + (128<<17); |
| x3 += 65536 + (128<<17); |
| // tried computing the shifts into temps, or'ing the temps to see |
| // if any were out of range, but that was slower |
| o[0] = stbi__clamp((x0+t3) >> 17); |
| o[7] = stbi__clamp((x0-t3) >> 17); |
| o[1] = stbi__clamp((x1+t2) >> 17); |
| o[6] = stbi__clamp((x1-t2) >> 17); |
| o[2] = stbi__clamp((x2+t1) >> 17); |
| o[5] = stbi__clamp((x2-t1) >> 17); |
| o[3] = stbi__clamp((x3+t0) >> 17); |
| o[4] = stbi__clamp((x3-t0) >> 17); |
| } |
| } |
| |
| #ifdef STBI_SSE2 |
| // sse2 integer IDCT. not the fastest possible implementation but it |
| // produces bit-identical results to the generic C version so it's |
| // fully "transparent". |
| static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64]) |
| { |
| // This is constructed to match our regular (generic) integer IDCT exactly. |
| __m128i row0, row1, row2, row3, row4, row5, row6, row7; |
| __m128i tmp; |
| |
| // dot product constant: even elems=x, odd elems=y |
| #define dct_const(x,y) _mm_setr_epi16((x),(y),(x),(y),(x),(y),(x),(y)) |
| |
| // out(0) = c0[even]*x + c0[odd]*y (c0, x, y 16-bit, out 32-bit) |
| // out(1) = c1[even]*x + c1[odd]*y |
| #define dct_rot(out0,out1, x,y,c0,c1) \ |
| __m128i c0##lo = _mm_unpacklo_epi16((x),(y)); \ |
| __m128i c0##hi = _mm_unpackhi_epi16((x),(y)); \ |
| __m128i out0##_l = _mm_madd_epi16(c0##lo, c0); \ |
| __m128i out0##_h = _mm_madd_epi16(c0##hi, c0); \ |
| __m128i out1##_l = _mm_madd_epi16(c0##lo, c1); \ |
| __m128i out1##_h = _mm_madd_epi16(c0##hi, c1) |
| |
| // out = in << 12 (in 16-bit, out 32-bit) |
| #define dct_widen(out, in) \ |
| __m128i out##_l = _mm_srai_epi32(_mm_unpacklo_epi16(_mm_setzero_si128(), (in)), 4); \ |
| __m128i out##_h = _mm_srai_epi32(_mm_unpackhi_epi16(_mm_setzero_si128(), (in)), 4) |
| |
| // wide add |
| #define dct_wadd(out, a, b) \ |
| __m128i out##_l = _mm_add_epi32(a##_l, b##_l); \ |
| __m128i out##_h = _mm_add_epi32(a##_h, b##_h) |
| |
| // wide sub |
| #define dct_wsub(out, a, b) \ |
| __m128i out##_l = _mm_sub_epi32(a##_l, b##_l); \ |
| __m128i out##_h = _mm_sub_epi32(a##_h, b##_h) |
| |
| // butterfly a/b, add bias, then shift by "s" and pack |
| #define dct_bfly32o(out0, out1, a,b,bias,s) \ |
| { \ |
| __m128i abiased_l = _mm_add_epi32(a##_l, bias); \ |
| __m128i abiased_h = _mm_add_epi32(a##_h, bias); \ |
| dct_wadd(sum, abiased, b); \ |
| dct_wsub(dif, abiased, b); \ |
| out0 = _mm_packs_epi32(_mm_srai_epi32(sum_l, s), _mm_srai_epi32(sum_h, s)); \ |
| out1 = _mm_packs_epi32(_mm_srai_epi32(dif_l, s), _mm_srai_epi32(dif_h, s)); \ |
| } |
| |
| // 8-bit interleave step (for transposes) |
| #define dct_interleave8(a, b) \ |
| tmp = a; \ |
| a = _mm_unpacklo_epi8(a, b); \ |
| b = _mm_unpackhi_epi8(tmp, b) |
| |
| // 16-bit interleave step (for transposes) |
| #define dct_interleave16(a, b) \ |
| tmp = a; \ |
| a = _mm_unpacklo_epi16(a, b); \ |
| b = _mm_unpackhi_epi16(tmp, b) |
| |
| #define dct_pass(bias,shift) \ |
| { \ |
| /* even part */ \ |
| dct_rot(t2e,t3e, row2,row6, rot0_0,rot0_1); \ |
| __m128i sum04 = _mm_add_epi16(row0, row4); \ |
| __m128i dif04 = _mm_sub_epi16(row0, row4); \ |
| dct_widen(t0e, sum04); \ |
| dct_widen(t1e, dif04); \ |
| dct_wadd(x0, t0e, t3e); \ |
| dct_wsub(x3, t0e, t3e); \ |
| dct_wadd(x1, t1e, t2e); \ |
| dct_wsub(x2, t1e, t2e); \ |
| /* odd part */ \ |
| dct_rot(y0o,y2o, row7,row3, rot2_0,rot2_1); \ |
| dct_rot(y1o,y3o, row5,row1, rot3_0,rot3_1); \ |
| __m128i sum17 = _mm_add_epi16(row1, row7); \ |
| __m128i sum35 = _mm_add_epi16(row3, row5); \ |
| dct_rot(y4o,y5o, sum17,sum35, rot1_0,rot1_1); \ |
| dct_wadd(x4, y0o, y4o); \ |
| dct_wadd(x5, y1o, y5o); \ |
| dct_wadd(x6, y2o, y5o); \ |
| dct_wadd(x7, y3o, y4o); \ |
| dct_bfly32o(row0,row7, x0,x7,bias,shift); \ |
| dct_bfly32o(row1,row6, x1,x6,bias,shift); \ |
| dct_bfly32o(row2,row5, x2,x5,bias,shift); \ |
| dct_bfly32o(row3,row4, x3,x4,bias,shift); \ |
| } |
| |
| __m128i rot0_0 = dct_const(stbi__f2f(0.5411961f), stbi__f2f(0.5411961f) + stbi__f2f(-1.847759065f)); |
| __m128i rot0_1 = dct_const(stbi__f2f(0.5411961f) + stbi__f2f( 0.765366865f), stbi__f2f(0.5411961f)); |
| __m128i rot1_0 = dct_const(stbi__f2f(1.175875602f) + stbi__f2f(-0.899976223f), stbi__f2f(1.175875602f)); |
| __m128i rot1_1 = dct_const(stbi__f2f(1.175875602f), stbi__f2f(1.175875602f) + stbi__f2f(-2.562915447f)); |
| __m128i rot2_0 = dct_const(stbi__f2f(-1.961570560f) + stbi__f2f( 0.298631336f), stbi__f2f(-1.961570560f)); |
| __m128i rot2_1 = dct_const(stbi__f2f(-1.961570560f), stbi__f2f(-1.961570560f) + stbi__f2f( 3.072711026f)); |
| __m128i rot3_0 = dct_const(stbi__f2f(-0.390180644f) + stbi__f2f( 2.053119869f), stbi__f2f(-0.390180644f)); |
| __m128i rot3_1 = dct_const(stbi__f2f(-0.390180644f), stbi__f2f(-0.390180644f) + stbi__f2f( 1.501321110f)); |
| |
| // rounding biases in column/row passes, see stbi__idct_block for explanation. |
| __m128i bias_0 = _mm_set1_epi32(512); |
| __m128i bias_1 = _mm_set1_epi32(65536 + (128<<17)); |
| |
| // load |
| row0 = _mm_load_si128((const __m128i *) (data + 0*8)); |
| row1 = _mm_load_si128((const __m128i *) (data + 1*8)); |
| row2 = _mm_load_si128((const __m128i *) (data + 2*8)); |
| row3 = _mm_load_si128((const __m128i *) (data + 3*8)); |
| row4 = _mm_load_si128((const __m128i *) (data + 4*8)); |
| row5 = _mm_load_si128((const __m128i *) (data + 5*8)); |
| row6 = _mm_load_si128((const __m128i *) (data + 6*8)); |
| row7 = _mm_load_si128((const __m128i *) (data + 7*8)); |
| |
| // column pass |
| dct_pass(bias_0, 10); |
| |
| { |
| // 16bit 8x8 transpose pass 1 |
| dct_interleave16(row0, row4); |
| dct_interleave16(row1, row5); |
| dct_interleave16(row2, row6); |
| dct_interleave16(row3, row7); |
| |
| // transpose pass 2 |
| dct_interleave16(row0, row2); |
| dct_interleave16(row1, row3); |
| dct_interleave16(row4, row6); |
| dct_interleave16(row5, row7); |
| |
| // transpose pass 3 |
| dct_interleave16(row0, row1); |
| dct_interleave16(row2, row3); |
| dct_interleave16(row4, row5); |
| dct_interleave16(row6, row7); |
| } |
| |
| // row pass |
| dct_pass(bias_1, 17); |
| |
| { |
| // pack |
| __m128i p0 = _mm_packus_epi16(row0, row1); // a0a1a2a3...a7b0b1b2b3...b7 |
| __m128i p1 = _mm_packus_epi16(row2, row3); |
| __m128i p2 = _mm_packus_epi16(row4, row5); |
| __m128i p3 = _mm_packus_epi16(row6, row7); |
| |
| // 8bit 8x8 transpose pass 1 |
| dct_interleave8(p0, p2); // a0e0a1e1... |
| dct_interleave8(p1, p3); // c0g0c1g1... |
| |
| // transpose pass 2 |
| dct_interleave8(p0, p1); // a0c0e0g0... |
| dct_interleave8(p2, p3); // b0d0f0h0... |
| |
| // transpose pass 3 |
| dct_interleave8(p0, p2); // a0b0c0d0... |
| dct_interleave8(p1, p3); // a4b4c4d4... |
| |
| // store |
| _mm_storel_epi64((__m128i *) out, p0); out += out_stride; |
| _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p0, 0x4e)); out += out_stride; |
| _mm_storel_epi64((__m128i *) out, p2); out += out_stride; |
| _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p2, 0x4e)); out += out_stride; |
| _mm_storel_epi64((__m128i *) out, p1); out += out_stride; |
| _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p1, 0x4e)); out += out_stride; |
| _mm_storel_epi64((__m128i *) out, p3); out += out_stride; |
| _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p3, 0x4e)); |
| } |
| |
| #undef dct_const |
| #undef dct_rot |
| #undef dct_widen |
| #undef dct_wadd |
| #undef dct_wsub |
| #undef dct_bfly32o |
| #undef dct_interleave8 |
| #undef dct_interleave16 |
| #undef dct_pass |
| } |
| |
| #endif // STBI_SSE2 |
| |
| #ifdef STBI_NEON |
| |
| // NEON integer IDCT. should produce bit-identical |
| // results to the generic C version. |
| static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64]) |
| { |
| int16x8_t row0, row1, row2, row3, row4, row5, row6, row7; |
| |
| int16x4_t rot0_0 = vdup_n_s16(stbi__f2f(0.5411961f)); |
| int16x4_t rot0_1 = vdup_n_s16(stbi__f2f(-1.847759065f)); |
| int16x4_t rot0_2 = vdup_n_s16(stbi__f2f( 0.765366865f)); |
| int16x4_t rot1_0 = vdup_n_s16(stbi__f2f( 1.175875602f)); |
| int16x4_t rot1_1 = vdup_n_s16(stbi__f2f(-0.899976223f)); |
| int16x4_t rot1_2 = vdup_n_s16(stbi__f2f(-2.562915447f)); |
| int16x4_t rot2_0 = vdup_n_s16(stbi__f2f(-1.961570560f)); |
| int16x4_t rot2_1 = vdup_n_s16(stbi__f2f(-0.390180644f)); |
| int16x4_t rot3_0 = vdup_n_s16(stbi__f2f( 0.298631336f)); |
| int16x4_t rot3_1 = vdup_n_s16(stbi__f2f( 2.053119869f)); |
| int16x4_t rot3_2 = vdup_n_s16(stbi__f2f( 3.072711026f)); |
| int16x4_t rot3_3 = vdup_n_s16(stbi__f2f( 1.501321110f)); |
| |
| #define dct_long_mul(out, inq, coeff) \ |
| int32x4_t out##_l = vmull_s16(vget_low_s16(inq), coeff); \ |
| int32x4_t out##_h = vmull_s16(vget_high_s16(inq), coeff) |
| |
| #define dct_long_mac(out, acc, inq, coeff) \ |
| int32x4_t out##_l = vmlal_s16(acc##_l, vget_low_s16(inq), coeff); \ |
| int32x4_t out##_h = vmlal_s16(acc##_h, vget_high_s16(inq), coeff) |
| |
| #define dct_widen(out, inq) \ |
| int32x4_t out##_l = vshll_n_s16(vget_low_s16(inq), 12); \ |
| int32x4_t out##_h = vshll_n_s16(vget_high_s16(inq), 12) |
| |
| // wide add |
| #define dct_wadd(out, a, b) \ |
| int32x4_t out##_l = vaddq_s32(a##_l, b##_l); \ |
| int32x4_t out##_h = vaddq_s32(a##_h, b##_h) |
| |
| // wide sub |
| #define dct_wsub(out, a, b) \ |
| int32x4_t out##_l = vsubq_s32(a##_l, b##_l); \ |
| int32x4_t out##_h = vsubq_s32(a##_h, b##_h) |
| |
| // butterfly a/b, then shift using "shiftop" by "s" and pack |
| #define dct_bfly32o(out0,out1, a,b,shiftop,s) \ |
| { \ |
| dct_wadd(sum, a, b); \ |
| dct_wsub(dif, a, b); \ |
| out0 = vcombine_s16(shiftop(sum_l, s), shiftop(sum_h, s)); \ |
| out1 = vcombine_s16(shiftop(dif_l, s), shiftop(dif_h, s)); \ |
| } |
| |
| #define dct_pass(shiftop, shift) \ |
| { \ |
| /* even part */ \ |
| int16x8_t sum26 = vaddq_s16(row2, row6); \ |
| dct_long_mul(p1e, sum26, rot0_0); \ |
| dct_long_mac(t2e, p1e, row6, rot0_1); \ |
| dct_long_mac(t3e, p1e, row2, rot0_2); \ |
| int16x8_t sum04 = vaddq_s16(row0, row4); \ |
| int16x8_t dif04 = vsubq_s16(row0, row4); \ |
| dct_widen(t0e, sum04); \ |
| dct_widen(t1e, dif04); \ |
| dct_wadd(x0, t0e, t3e); \ |
| dct_wsub(x3, t0e, t3e); \ |
| dct_wadd(x1, t1e, t2e); \ |
| dct_wsub(x2, t1e, t2e); \ |
| /* odd part */ \ |
| int16x8_t sum15 = vaddq_s16(row1, row5); \ |
| int16x8_t sum17 = vaddq_s16(row1, row7); \ |
| int16x8_t sum35 = vaddq_s16(row3, row5); \ |
| int16x8_t sum37 = vaddq_s16(row3, row7); \ |
| int16x8_t sumodd = vaddq_s16(sum17, sum35); \ |
| dct_long_mul(p5o, sumodd, rot1_0); \ |
| dct_long_mac(p1o, p5o, sum17, rot1_1); \ |
| dct_long_mac(p2o, p5o, sum35, rot1_2); \ |
| dct_long_mul(p3o, sum37, rot2_0); \ |
| dct_long_mul(p4o, sum15, rot2_1); \ |
| dct_wadd(sump13o, p1o, p3o); \ |
| dct_wadd(sump24o, p2o, p4o); \ |
| dct_wadd(sump23o, p2o, p3o); \ |
| dct_wadd(sump14o, p1o, p4o); \ |
| dct_long_mac(x4, sump13o, row7, rot3_0); \ |
| dct_long_mac(x5, sump24o, row5, rot3_1); \ |
| dct_long_mac(x6, sump23o, row3, rot3_2); \ |
| dct_long_mac(x7, sump14o, row1, rot3_3); \ |
| dct_bfly32o(row0,row7, x0,x7,shiftop,shift); \ |
| dct_bfly32o(row1,row6, x1,x6,shiftop,shift); \ |
| dct_bfly32o(row2,row5, x2,x5,shiftop,shift); \ |
| dct_bfly32o(row3,row4, x3,x4,shiftop,shift); \ |
| } |
| |
| // load |
| row0 = vld1q_s16(data + 0*8); |
| row1 = vld1q_s16(data + 1*8); |
| row2 = vld1q_s16(data + 2*8); |
| row3 = vld1q_s16(data + 3*8); |
| row4 = vld1q_s16(data + 4*8); |
| row5 = vld1q_s16(data + 5*8); |
| row6 = vld1q_s16(data + 6*8); |
| row7 = vld1q_s16(data + 7*8); |
| |
| // add DC bias |
| row0 = vaddq_s16(row0, vsetq_lane_s16(1024, vdupq_n_s16(0), 0)); |
| |
| // column pass |
| dct_pass(vrshrn_n_s32, 10); |
| |
| // 16bit 8x8 transpose |
| { |
| // these three map to a single VTRN.16, VTRN.32, and VSWP, respectively. |
| // whether compilers actually get this is another story, sadly. |
| #define dct_trn16(x, y) { int16x8x2_t t = vtrnq_s16(x, y); x = t.val[0]; y = t.val[1]; } |
| #define dct_trn32(x, y) { int32x4x2_t t = vtrnq_s32(vreinterpretq_s32_s16(x), vreinterpretq_s32_s16(y)); x = vreinterpretq_s16_s32(t.val[0]); y = vreinterpretq_s16_s32(t.val[1]); } |
| #define dct_trn64(x, y) { int16x8_t x0 = x; int16x8_t y0 = y; x = vcombine_s16(vget_low_s16(x0), vget_low_s16(y0)); y = vcombine_s16(vget_high_s16(x0), vget_high_s16(y0)); } |
| |
| // pass 1 |
| dct_trn16(row0, row1); // a0b0a2b2a4b4a6b6 |
| dct_trn16(row2, row3); |
| dct_trn16(row4, row5); |
| dct_trn16(row6, row7); |
| |
| // pass 2 |
| dct_trn32(row0, row2); // a0b0c0d0a4b4c4d4 |
| dct_trn32(row1, row3); |
| dct_trn32(row4, row6); |
| dct_trn32(row5, row7); |
| |
| // pass 3 |
| dct_trn64(row0, row4); // a0b0c0d0e0f0g0h0 |
| dct_trn64(row1, row5); |
| dct_trn64(row2, row6); |
| dct_trn64(row3, row7); |
| |
| #undef dct_trn16 |
| #undef dct_trn32 |
| #undef dct_trn64 |
| } |
| |
| // row pass |
| // vrshrn_n_s32 only supports shifts up to 16, we need |
| // 17. so do a non-rounding shift of 16 first then follow |
| // up with a rounding shift by 1. |
| dct_pass(vshrn_n_s32, 16); |
| |
| { |
| // pack and round |
| uint8x8_t p0 = vqrshrun_n_s16(row0, 1); |
| uint8x8_t p1 = vqrshrun_n_s16(row1, 1); |
| uint8x8_t p2 = vqrshrun_n_s16(row2, 1); |
| uint8x8_t p3 = vqrshrun_n_s16(row3, 1); |
| uint8x8_t p4 = vqrshrun_n_s16(row4, 1); |
| uint8x8_t p5 = vqrshrun_n_s16(row5, 1); |
| uint8x8_t p6 = vqrshrun_n_s16(row6, 1); |
| uint8x8_t p7 = vqrshrun_n_s16(row7, 1); |
| |
| // again, these can translate into one instruction, but often don't. |
| #define dct_trn8_8(x, y) { uint8x8x2_t t = vtrn_u8(x, y); x = t.val[0]; y = t.val[1]; } |
| #define dct_trn8_16(x, y) { uint16x4x2_t t = vtrn_u16(vreinterpret_u16_u8(x), vreinterpret_u16_u8(y)); x = vreinterpret_u8_u16(t.val[0]); y = vreinterpret_u8_u16(t.val[1]); } |
| #define dct_trn8_32(x, y) { uint32x2x2_t t = vtrn_u32(vreinterpret_u32_u8(x), vreinterpret_u32_u8(y)); x = vreinterpret_u8_u32(t.val[0]); y = vreinterpret_u8_u32(t.val[1]); } |
| |
| // sadly can't use interleaved stores here since we only write |
| // 8 bytes to each scan line! |
| |
| // 8x8 8-bit transpose pass 1 |
| dct_trn8_8(p0, p1); |
| dct_trn8_8(p2, p3); |
| dct_trn8_8(p4, p5); |
| dct_trn8_8(p6, p7); |
| |
| // pass 2 |
| dct_trn8_16(p0, p2); |
| dct_trn8_16(p1, p3); |
| dct_trn8_16(p4, p6); |
| dct_trn8_16(p5, p7); |
| |
| // pass 3 |
| dct_trn8_32(p0, p4); |
| dct_trn8_32(p1, p5); |
| dct_trn8_32(p2, p6); |
| dct_trn8_32(p3, p7); |
| |
| // store |
| vst1_u8(out, p0); out += out_stride; |
| vst1_u8(out, p1); out += out_stride; |
| vst1_u8(out, p2); out += out_stride; |
| vst1_u8(out, p3); out += out_stride; |
| vst1_u8(out, p4); out += out_stride; |
| vst1_u8(out, p5); out += out_stride; |
| vst1_u8(out, p6); out += out_stride; |
| vst1_u8(out, p7); |
| |
| #undef dct_trn8_8 |
| #undef dct_trn8_16 |
| #undef dct_trn8_32 |
| } |
| |
| #undef dct_long_mul |
| #undef dct_long_mac |
| #undef dct_widen |
| #undef dct_wadd |
| #undef dct_wsub |
| #undef dct_bfly32o |
| #undef dct_pass |
| } |
| |
| #endif // STBI_NEON |
| |
| #define STBI__MARKER_none 0xff |
| // if there's a pending marker from the entropy stream, return that |
| // otherwise, fetch from the stream and get a marker. if there's no |
| // marker, return 0xff, which is never a valid marker value |
| static stbi_uc stbi__get_marker(stbi__jpeg *j) |
| { |
| stbi_uc x; |
| if (j->marker != STBI__MARKER_none) { x = j->marker; j->marker = STBI__MARKER_none; return x; } |
| x = stbi__get8(j->s); |
| if (x != 0xff) return STBI__MARKER_none; |
| while (x == 0xff) |
| x = stbi__get8(j->s); // consume repeated 0xff fill bytes |
| return x; |
| } |
| |
| // in each scan, we'll have scan_n components, and the order |
| // of the components is specified by order[] |
| #define STBI__RESTART(x) ((x) >= 0xd0 && (x) <= 0xd7) |
| |
| // after a restart interval, stbi__jpeg_reset the entropy decoder and |
| // the dc prediction |
| static void stbi__jpeg_reset(stbi__jpeg *j) |
| { |
| j->code_bits = 0; |
| j->code_buffer = 0; |
| j->nomore = 0; |
| j->img_comp[0].dc_pred = j->img_comp[1].dc_pred = j->img_comp[2].dc_pred = j->img_comp[3].dc_pred = 0; |
| j->marker = STBI__MARKER_none; |
| j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff; |
| j->eob_run = 0; |
| // no more than 1<<31 MCUs if no restart_interal? that's plenty safe, |
| // since we don't even allow 1<<30 pixels |
| } |
| |
| static int stbi__parse_entropy_coded_data(stbi__jpeg *z) |
| { |
| stbi__jpeg_reset(z); |
| if (!z->progressive) { |
| if (z->scan_n == 1) { |
| int i,j; |
| STBI_SIMD_ALIGN(short, data[64]); |
| int n = z->order[0]; |
| // non-interleaved data, we just need to process one block at a time, |
| // in trivial scanline order |
| // number of blocks to do just depends on how many actual "pixels" this |
| // component has, independent of interleaved MCU blocking and such |
| int w = (z->img_comp[n].x+7) >> 3; |
| int h = (z->img_comp[n].y+7) >> 3; |
| for (j=0; j < h; ++j) { |
| for (i=0; i < w; ++i) { |
| int ha = z->img_comp[n].ha; |
| if (!stbi__jpeg_decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0; |
| z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data); |
| // every data block is an MCU, so countdown the restart interval |
| if (--z->todo <= 0) { |
| if (z->code_bits < 24) stbi__grow_buffer_unsafe(z); |
| // if it's NOT a restart, then just bail, so we get corrupt data |
| // rather than no data |
| if (!STBI__RESTART(z->marker)) return 1; |
| stbi__jpeg_reset(z); |
| } |
| } |
| } |
| return 1; |
| } else { // interleaved |
| int i,j,k,x,y; |
| STBI_SIMD_ALIGN(short, data[64]); |
| for (j=0; j < z->img_mcu_y; ++j) { |
| for (i=0; i < z->img_mcu_x; ++i) { |
| // scan an interleaved mcu... process scan_n components in order |
| for (k=0; k < z->scan_n; ++k) { |
| int n = z->order[k]; |
| // scan out an mcu's worth of this component; that's just determined |
| // by the basic H and V specified for the component |
| for (y=0; y < z->img_comp[n].v; ++y) { |
| for (x=0; x < z->img_comp[n].h; ++x) { |
| int x2 = (i*z->img_comp[n].h + x)*8; |
| int y2 = (j*z->img_comp[n].v + y)*8; |
| int ha = z->img_comp[n].ha; |
| if (!stbi__jpeg_decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0; |
| z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*y2+x2, z->img_comp[n].w2, data); |
| } |
| } |
| } |
| // after all interleaved components, that's an interleaved MCU, |
| // so now count down the restart interval |
| if (--z->todo <= 0) { |
| if (z->code_bits < 24) stbi__grow_buffer_unsafe(z); |
| if (!STBI__RESTART(z->marker)) return 1; |
| stbi__jpeg_reset(z); |
| } |
| } |
| } |
| return 1; |
| } |
| } else { |
| if (z->scan_n == 1) { |
| int i,j; |
| int n = z->order[0]; |
| // non-interleaved data, we just need to process one block at a time, |
| // in trivial scanline order |
| // number of blocks to do just depends on how many actual "pixels" this |
| // component has, independent of interleaved MCU blocking and such |
| int w = (z->img_comp[n].x+7) >> 3; |
| int h = (z->img_comp[n].y+7) >> 3; |
| for (j=0; j < h; ++j) { |
| for (i=0; i < w; ++i) { |
| short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w); |
| if (z->spec_start == 0) { |
| if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n)) |
| return 0; |
| } else { |
| int ha = z->img_comp[n].ha; |
| if (!stbi__jpeg_decode_block_prog_ac(z, data, &z->huff_ac[ha], z->fast_ac[ha])) |
| return 0; |
| } |
| // every data block is an MCU, so countdown the restart interval |
| if (--z->todo <= 0) { |
| if (z->code_bits < 24) stbi__grow_buffer_unsafe(z); |
| if (!STBI__RESTART(z->marker)) return 1; |
| stbi__jpeg_reset(z); |
| } |
| } |
| } |
| return 1; |
| } else { // interleaved |
| int i,j,k,x,y; |
| for (j=0; j < z->img_mcu_y; ++j) { |
| for (i=0; i < z->img_mcu_x; ++i) { |
| // scan an interleaved mcu... process scan_n components in order |
| for (k=0; k < z->scan_n; ++k) { |
| int n = z->order[k]; |
| // scan out an mcu's worth of this component; that's just determined |
| // by the basic H and V specified for the component |
| for (y=0; y < z->img_comp[n].v; ++y) { |
| for (x=0; x < z->img_comp[n].h; ++x) { |
| int x2 = (i*z->img_comp[n].h + x); |
| int y2 = (j*z->img_comp[n].v + y); |
| short *data = z->img_comp[n].coeff + 64 * (x2 + y2 * z->img_comp[n].coeff_w); |
| if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n)) |
| return 0; |
| } |
| } |
| } |
| // after all interleaved components, that's an interleaved MCU, |
| // so now count down the restart interval |
| if (--z->todo <= 0) { |
| if (z->code_bits < 24) stbi__grow_buffer_unsafe(z); |
| if (!STBI__RESTART(z->marker)) return 1; |
| stbi__jpeg_reset(z); |
| } |
| } |
| } |
| return 1; |
| } |
| } |
| } |
| |
| static void stbi__jpeg_dequantize(short *data, stbi__uint16 *dequant) |
| { |
| int i; |
| for (i=0; i < 64; ++i) |
| data[i] *= dequant[i]; |
| } |
| |
| static void stbi__jpeg_finish(stbi__jpeg *z) |
| { |
| if (z->progressive) { |
| // dequantize and idct the data |
| int i,j,n; |
| for (n=0; n < z->s->img_n; ++n) { |
| int w = (z->img_comp[n].x+7) >> 3; |
| int h = (z->img_comp[n].y+7) >> 3; |
| for (j=0; j < h; ++j) { |
| for (i=0; i < w; ++i) { |
| short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w); |
| stbi__jpeg_dequantize(data, z->dequant[z->img_comp[n].tq]); |
| z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data); |
| } |
| } |
| } |
| } |
| } |
| |
| static int stbi__process_marker(stbi__jpeg *z, int m) |
| { |
| int L; |
| switch (m) { |
| case STBI__MARKER_none: // no marker found |
| return stbi__err("expected marker","Corrupt JPEG"); |
| |
| case 0xDD: // DRI - specify restart interval |
| if (stbi__get16be(z->s) != 4) return stbi__err("bad DRI len","Corrupt JPEG"); |
| z->restart_interval = stbi__get16be(z->s); |
| return 1; |
| |
| case 0xDB: // DQT - define quantization table |
| L = stbi__get16be(z->s)-2; |
| while (L > 0) { |
| int q = stbi__get8(z->s); |
| int p = q >> 4, sixteen = (p != 0); |
| int t = q & 15,i; |
| if (p != 0 && p != 1) return stbi__err("bad DQT type","Corrupt JPEG"); |
| if (t > 3) return stbi__err("bad DQT table","Corrupt JPEG"); |
| |
| for (i=0; i < 64; ++i) |
| z->dequant[t][stbi__jpeg_dezigzag[i]] = (stbi__uint16)(sixteen ? stbi__get16be(z->s) : stbi__get8(z->s)); |
| L -= (sixteen ? 129 : 65); |
| } |
| return L==0; |
| |
| case 0xC4: // DHT - define huffman table |
| L = stbi__get16be(z->s)-2; |
| while (L > 0) { |
| stbi_uc *v; |
| int sizes[16],i,n=0; |
| int q = stbi__get8(z->s); |
| int tc = q >> 4; |
| int th = q & 15; |
| if (tc > 1 || th > 3) return stbi__err("bad DHT header","Corrupt JPEG"); |
| for (i=0; i < 16; ++i) { |
| sizes[i] = stbi__get8(z->s); |
| n += sizes[i]; |
| } |
| L -= 17; |
| if (tc == 0) { |
| if (!stbi__build_huffman(z->huff_dc+th, sizes)) return 0; |
| v = z->huff_dc[th].values; |
| } else { |
| if (!stbi__build_huffman(z->huff_ac+th, sizes)) return 0; |
| v = z->huff_ac[th].values; |
| } |
| for (i=0; i < n; ++i) |
| v[i] = stbi__get8(z->s); |
| if (tc != 0) |
| stbi__build_fast_ac(z->fast_ac[th], z->huff_ac + th); |
| L -= n; |
| } |
| return L==0; |
| } |
| |
| // check for comment block or APP blocks |
| if ((m >= 0xE0 && m <= 0xEF) || m == 0xFE) { |
| L = stbi__get16be(z->s); |
| if (L < 2) { |
| if (m == 0xFE) |
| return stbi__err("bad COM len","Corrupt JPEG"); |
| else |
| return stbi__err("bad APP len","Corrupt JPEG"); |
| } |
| L -= 2; |
| |
| if (m == 0xE0 && L >= 5) { // JFIF APP0 segment |
| static const unsigned char tag[5] = {'J','F','I','F','\0'}; |
| int ok = 1; |
| int i; |
| for (i=0; i < 5; ++i) |
| if (stbi__get8(z->s) != tag[i]) |
| ok = 0; |
| L -= 5; |
| if (ok) |
| z->jfif = 1; |
| } else if (m == 0xEE && L >= 12) { // Adobe APP14 segment |
| static const unsigned char tag[6] = {'A','d','o','b','e','\0'}; |
| int ok = 1; |
| int i; |
| for (i=0; i < 6; ++i) |
| if (stbi__get8(z->s) != tag[i]) |
| ok = 0; |
| L -= 6; |
| if (ok) { |
| stbi__get8(z->s); // version |
| stbi__get16be(z->s); // flags0 |
| stbi__get16be(z->s); // flags1 |
| z->app14_color_transform = stbi__get8(z->s); // color transform |
| L -= 6; |
| } |
| } |
| |
| stbi__skip(z->s, L); |
| return 1; |
| } |
| |
| return stbi__err("unknown marker","Corrupt JPEG"); |
| } |
| |
| // after we see SOS |
| static int stbi__process_scan_header(stbi__jpeg *z) |
| { |
| int i; |
| int Ls = stbi__get16be(z->s); |
| z->scan_n = stbi__get8(z->s); |
| if (z->scan_n < 1 || z->scan_n > 4 || z->scan_n > (int) z->s->img_n) return stbi__err("bad SOS component count","Corrupt JPEG"); |
| if (Ls != 6+2*z->scan_n) return stbi__err("bad SOS len","Corrupt JPEG"); |
| for (i=0; i < z->scan_n; ++i) { |
| int id = stbi__get8(z->s), which; |
| int q = stbi__get8(z->s); |
| for (which = 0; which < z->s->img_n; ++which) |
| if (z->img_comp[which].id == id) |
| break; |
| if (which == z->s->img_n) return 0; // no match |
| z->img_comp[which].hd = q >> 4; if (z->img_comp[which].hd > 3) return stbi__err("bad DC huff","Corrupt JPEG"); |
| z->img_comp[which].ha = q & 15; if (z->img_comp[which].ha > 3) return stbi__err("bad AC huff","Corrupt JPEG"); |
| z->order[i] = which; |
| } |
| |
| { |
| int aa; |
| z->spec_start = stbi__get8(z->s); |
| z->spec_end = stbi__get8(z->s); // should be 63, but might be 0 |
| aa = stbi__get8(z->s); |
| z->succ_high = (aa >> 4); |
| z->succ_low = (aa & 15); |
| if (z->progressive) { |
| if (z->spec_start > 63 || z->spec_end > 63 || z->spec_start > z->spec_end || z->succ_high > 13 || z->succ_low > 13) |
| return stbi__err("bad SOS", "Corrupt JPEG"); |
| } else { |
| if (z->spec_start != 0) return stbi__err("bad SOS","Corrupt JPEG"); |
| if (z->succ_high != 0 || z->succ_low != 0) return stbi__err("bad SOS","Corrupt JPEG"); |
| z->spec_end = 63; |
| } |
| } |
| |
| return 1; |
| } |
| |
| static int stbi__free_jpeg_components(stbi__jpeg *z, int ncomp, int why) |
| { |
| int i; |
| for (i=0; i < ncomp; ++i) { |
| if (z->img_comp[i].raw_data) { |
| STBI_FREE(z->img_comp[i].raw_data); |
| z->img_comp[i].raw_data = NULL; |
| z->img_comp[i].data = NULL; |
| } |
| if (z->img_comp[i].raw_coeff) { |
| STBI_FREE(z->img_comp[i].raw_coeff); |
| z->img_comp[i].raw_coeff = 0; |
| z->img_comp[i].coeff = 0; |
| } |
| if (z->img_comp[i].linebuf) { |
| STBI_FREE(z->img_comp[i].linebuf); |
| z->img_comp[i].linebuf = NULL; |
| } |
| } |
| return why; |
| } |
| |
| static int stbi__process_frame_header(stbi__jpeg *z, int scan) |
| { |
| stbi__context *s = z->s; |
| int Lf,p,i,q, h_max=1,v_max=1,c; |
| Lf = stbi__get16be(s); if (Lf < 11) return stbi__err("bad SOF len","Corrupt JPEG"); // JPEG |
| p = stbi__get8(s); if (p != 8) return stbi__err("only 8-bit","JPEG format not supported: 8-bit only"); // JPEG baseline |
| s->img_y = stbi__get16be(s); if (s->img_y == 0) return stbi__err("no header height", "JPEG format not supported: delayed height"); // Legal, but we don't handle it--but neither does IJG |
| s->img_x = stbi__get16be(s); if (s->img_x == 0) return stbi__err("0 width","Corrupt JPEG"); // JPEG requires |
| c = stbi__get8(s); |
| if (c != 3 && c != 1 && c != 4) return stbi__err("bad component count","Corrupt JPEG"); |
| s->img_n = c; |
| for (i=0; i < c; ++i) { |
| z->img_comp[i].data = NULL; |
| z->img_comp[i].linebuf = NULL; |
| } |
| |
| if (Lf != 8+3*s->img_n) return stbi__err("bad SOF len","Corrupt JPEG"); |
| |
| z->rgb = 0; |
| for (i=0; i < s->img_n; ++i) { |
| static const unsigned char rgb[3] = { 'R', 'G', 'B' }; |
| z->img_comp[i].id = stbi__get8(s); |
| if (s->img_n == 3 && z->img_comp[i].id == rgb[i]) |
| ++z->rgb; |
| q = stbi__get8(s); |
| z->img_comp[i].h = (q >> 4); if (!z->img_comp[i].h || z->img_comp[i].h > 4) return stbi__err("bad H","Corrupt JPEG"); |
| z->img_comp[i].v = q & 15; if (!z->img_comp[i].v || z->img_comp[i].v > 4) return stbi__err("bad V","Corrupt JPEG"); |
| z->img_comp[i].tq = stbi__get8(s); if (z->img_comp[i].tq > 3) return stbi__err("bad TQ","Corrupt JPEG"); |
| } |
| |
| if (scan != STBI__SCAN_load) return 1; |
| |
| if (!stbi__mad3sizes_valid(s->img_x, s->img_y, s->img_n, 0)) return stbi__err("too large", "Image too large to decode"); |
| |
| for (i=0; i < s->img_n; ++i) { |
| if (z->img_comp[i].h > h_max) h_max = z->img_comp[i].h; |
| if (z->img_comp[i].v > v_max) v_max = z->img_comp[i].v; |
| } |
| |
| // compute interleaved mcu info |
| z->img_h_max = h_max; |
| z->img_v_max = v_max; |
| z->img_mcu_w = h_max * 8; |
| z->img_mcu_h = v_max * 8; |
| // these sizes can't be more than 17 bits |
| z->img_mcu_x = (s->img_x + z->img_mcu_w-1) / z->img_mcu_w; |
| z->img_mcu_y = (s->img_y + z->img_mcu_h-1) / z->img_mcu_h; |
| |
| for (i=0; i < s->img_n; ++i) { |
| // number of effective pixels (e.g. for non-interleaved MCU) |
| z->img_comp[i].x = (s->img_x * z->img_comp[i].h + h_max-1) / h_max; |
| z->img_comp[i].y = (s->img_y * z->img_comp[i].v + v_max-1) / v_max; |
| // to simplify generation, we'll allocate enough memory to decode |
| // the bogus oversized data from using interleaved MCUs and their |
| // big blocks (e.g. a 16x16 iMCU on an image of width 33); we won't |
| // discard the extra data until colorspace conversion |
| // |
| // img_mcu_x, img_mcu_y: <=17 bits; comp[i].h and .v are <=4 (checked earlier) |
| // so these muls can't overflow with 32-bit ints (which we require) |
| z->img_comp[i].w2 = z->img_mcu_x * z->img_comp[i].h * 8; |
| z->img_comp[i].h2 = z->img_mcu_y * z->img_comp[i].v * 8; |
| z->img_comp[i].coeff = 0; |
| z->img_comp[i].raw_coeff = 0; |
| z->img_comp[i].linebuf = NULL; |
| z->img_comp[i].raw_data = stbi__malloc_mad2(z->img_comp[i].w2, z->img_comp[i].h2, 15); |
| if (z->img_comp[i].raw_data == NULL) |
| return stbi__free_jpeg_components(z, i+1, stbi__err("outofmem", "Out of memory")); |
| // align blocks for idct using mmx/sse |
| z->img_comp[i].data = (stbi_uc*) (((size_t) z->img_comp[i].raw_data + 15) & ~15); |
| if (z->progressive) { |
| // w2, h2 are multiples of 8 (see above) |
| z->img_comp[i].coeff_w = z->img_comp[i].w2 / 8; |
| z->img_comp[i].coeff_h = z->img_comp[i].h2 / 8; |
| z->img_comp[i].raw_coeff = stbi__malloc_mad3(z->img_comp[i].w2, z->img_comp[i].h2, sizeof(short), 15); |
| if (z->img_comp[i].raw_coeff == NULL) |
| return stbi__free_jpeg_components(z, i+1, stbi__err("outofmem", "Out of memory")); |
| z->img_comp[i].coeff = (short*) (((size_t) z->img_comp[i].raw_coeff + 15) & ~15); |
| } |
| } |
| |
| return 1; |
| } |
| |
| // use comparisons since in some cases we handle more than one case (e.g. SOF) |
| #define stbi__DNL(x) ((x) == 0xdc) |
| #define stbi__SOI(x) ((x) == 0xd8) |
| #define stbi__EOI(x) ((x) == 0xd9) |
| #define stbi__SOF(x) ((x) == 0xc0 || (x) == 0xc1 || (x) == 0xc2) |
| #define stbi__SOS(x) ((x) == 0xda) |
| |
| #define stbi__SOF_progressive(x) ((x) == 0xc2) |
| |
| static int stbi__decode_jpeg_header(stbi__jpeg *z, int scan) |
| { |
| int m; |
| z->jfif = 0; |
| z->app14_color_transform = -1; // valid values are 0,1,2 |
| z->marker = STBI__MARKER_none; // initialize cached marker to empty |
| m = stbi__get_marker(z); |
| if (!stbi__SOI(m)) return stbi__err("no SOI","Corrupt JPEG"); |
| if (scan == STBI__SCAN_type) return 1; |
| m = stbi__get_marker(z); |
| while (!stbi__SOF(m)) { |
| if (!stbi__process_marker(z,m)) return 0; |
| m = stbi__get_marker(z); |
| while (m == STBI__MARKER_none) { |
| // some files have extra padding after their blocks, so ok, we'll scan |
| if (stbi__at_eof(z->s)) return stbi__err("no SOF", "Corrupt JPEG"); |
| m = stbi__get_marker(z); |
| } |
| } |
| z->progressive = stbi__SOF_progressive(m); |
| if (!stbi__process_frame_header(z, scan)) return 0; |
| return 1; |
| } |
| |
| // decode image to YCbCr format |
| static int stbi__decode_jpeg_image(stbi__jpeg *j) |
| { |
| int m; |
| for (m = 0; m < 4; m++) { |
| j->img_comp[m].raw_data = NULL; |
| j->img_comp[m].raw_coeff = NULL; |
| } |
| j->restart_interval = 0; |
| if (!stbi__decode_jpeg_header(j, STBI__SCAN_load)) return 0; |
| m = stbi__get_marker(j); |
| while (!stbi__EOI(m)) { |
| if (stbi__SOS(m)) { |
| if (!stbi__process_scan_header(j)) return 0; |
| if (!stbi__parse_entropy_coded_data(j)) return 0; |
| if (j->marker == STBI__MARKER_none ) { |
| // handle 0s at the end of image data from IP Kamera 9060 |
| while (!stbi__at_eof(j->s)) { |
| int x = stbi__get8(j->s); |
| if (x == 255) { |
| j->marker = stbi__get8(j->s); |
| break; |
| } |
| } |
| // if we reach eof without hitting a marker, stbi__get_marker() below will fail and we'll eventually return 0 |
| } |
| } else if (stbi__DNL(m)) { |
| int Ld = stbi__get16be(j->s); |
| stbi__uint32 NL = stbi__get16be(j->s); |
| if (Ld != 4) return stbi__err("bad DNL len", "Corrupt JPEG"); |
| if (NL != j->s->img_y) return stbi__err("bad DNL height", "Corrupt JPEG"); |
| } else { |
| if (!stbi__process_marker(j, m)) return 0; |
| } |
| m = stbi__get_marker(j); |
| } |
| if (j->progressive) |
| stbi__jpeg_finish(j); |
| return 1; |
| } |
| |
| // static jfif-centered resampling (across block boundaries) |
| |
| typedef stbi_uc *(*resample_row_func)(stbi_uc *out, stbi_uc *in0, stbi_uc *in1, |
| int w, int hs); |
| |
| #define stbi__div4(x) ((stbi_uc) ((x) >> 2)) |
| |
| static stbi_uc *resample_row_1(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) |
| { |
| STBI_NOTUSED(out); |
| STBI_NOTUSED(in_far); |
| STBI_NOTUSED(w); |
| STBI_NOTUSED(hs); |
| return in_near; |
| } |
| |
| static stbi_uc* stbi__resample_row_v_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) |
| { |
| // need to generate two samples vertically for every one in input |
| int i; |
| STBI_NOTUSED(hs); |
| for (i=0; i < w; ++i) |
| out[i] = stbi__div4(3*in_near[i] + in_far[i] + 2); |
| return out; |
| } |
| |
| static stbi_uc* stbi__resample_row_h_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) |
| { |
| // need to generate two samples horizontally for every one in input |
| int i; |
| stbi_uc *input = in_near; |
| |
| if (w == 1) { |
| // if only one sample, can't do any interpolation |
| out[0] = out[1] = input[0]; |
| return out; |
| } |
| |
| out[0] = input[0]; |
| out[1] = stbi__div4(input[0]*3 + input[1] + 2); |
| for (i=1; i < w-1; ++i) { |
| int n = 3*input[i]+2; |
| out[i*2+0] = stbi__div4(n+input[i-1]); |
| out[i*2+1] = stbi__div4(n+input[i+1]); |
| } |
| out[i*2+0] = stbi__div4(input[w-2]*3 + input[w-1] + 2); |
| out[i*2+1] = input[w-1]; |
| |
| STBI_NOTUSED(in_far); |
| STBI_NOTUSED(hs); |
| |
| return out; |
| } |
| |
| #define stbi__div16(x) ((stbi_uc) ((x) >> 4)) |
| |
| static stbi_uc *stbi__resample_row_hv_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) |
| { |
| // need to generate 2x2 samples for every one in input |
| int i,t0,t1; |
| if (w == 1) { |
| out[0] = out[1] = stbi__div4(3*in_near[0] + in_far[0] + 2); |
| return out; |
| } |
| |
| t1 = 3*in_near[0] + in_far[0]; |
| out[0] = stbi__div4(t1+2); |
| for (i=1; i < w; ++i) { |
| t0 = t1; |
| t1 = 3*in_near[i]+in_far[i]; |
| out[i*2-1] = stbi__div16(3*t0 + t1 + 8); |
| out[i*2 ] = stbi__div16(3*t1 + t0 + 8); |
| } |
| out[w*2-1] = stbi__div4(t1+2); |
| |
| STBI_NOTUSED(hs); |
| |
| return out; |
| } |
| |
| #if defined(STBI_SSE2) || defined(STBI_NEON) |
| static stbi_uc *stbi__resample_row_hv_2_simd(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) |
| { |
| // need to generate 2x2 samples for every one in input |
| int i=0,t0,t1; |
| |
| if (w == 1) { |
| out[0] = out[1] = stbi__div4(3*in_near[0] + in_far[0] + 2); |
| return out; |
| } |
| |
| t1 = 3*in_near[0] + in_far[0]; |
| // process groups of 8 pixels for as long as we can. |
| // note we can't handle the last pixel in a row in this loop |
| // because we need to handle the filter boundary conditions. |
| for (; i < ((w-1) & ~7); i += 8) { |
| #if defined(STBI_SSE2) |
| // load and perform the vertical filtering pass |
| // this uses 3*x + y = 4*x + (y - x) |
| __m128i zero = _mm_setzero_si128(); |
| __m128i farb = _mm_loadl_epi64((__m128i *) (in_far + i)); |
| __m128i nearb = _mm_loadl_epi64((__m128i *) (in_near + i)); |
| __m128i farw = _mm_unpacklo_epi8(farb, zero); |
| __m128i nearw = _mm_unpacklo_epi8(nearb, zero); |
| __m128i diff = _mm_sub_epi16(farw, nearw); |
| __m128i nears = _mm_slli_epi16(nearw, 2); |
| __m128i curr = _mm_add_epi16(nears, diff); // current row |
| |
| // horizontal filter works the same based on shifted vers of current |
| // row. "prev" is current row shifted right by 1 pixel; we need to |
| // insert the previous pixel value (from t1). |
| // "next" is current row shifted left by 1 pixel, with first pixel |
| // of next block of 8 pixels added in. |
| __m128i prv0 = _mm_slli_si128(curr, 2); |
| __m128i nxt0 = _mm_srli_si128(curr, 2); |
| __m128i prev = _mm_insert_epi16(prv0, t1, 0); |
| __m128i next = _mm_insert_epi16(nxt0, 3*in_near[i+8] + in_far[i+8], 7); |
| |
| // horizontal filter, polyphase implementation since it's convenient: |
| // even pixels = 3*cur + prev = cur*4 + (prev - cur) |
| // odd pixels = 3*cur + next = cur*4 + (next - cur) |
| // note the shared term. |
| __m128i bias = _mm_set1_epi16(8); |
| __m128i curs = _mm_slli_epi16(curr, 2); |
| __m128i prvd = _mm_sub_epi16(prev, curr); |
| __m128i nxtd = _mm_sub_epi16(next, curr); |
| __m128i curb = _mm_add_epi16(curs, bias); |
| __m128i even = _mm_add_epi16(prvd, curb); |
| __m128i odd = _mm_add_epi16(nxtd, curb); |
| |
| // interleave even and odd pixels, then undo scaling. |
| __m128i int0 = _mm_unpacklo_epi16(even, odd); |
| __m128i int1 = _mm_unpackhi_epi16(even, odd); |
| __m128i de0 = _mm_srli_epi16(int0, 4); |
| __m128i de1 = _mm_srli_epi16(int1, 4); |
| |
| // pack and write output |
| __m128i outv = _mm_packus_epi16(de0, de1); |
| _mm_storeu_si128((__m128i *) (out + i*2), outv); |
| #elif defined(STBI_NEON) |
| // load and perform the vertical filtering pass |
| // this uses 3*x + y = 4*x + (y - x) |
| uint8x8_t farb = vld1_u8(in_far + i); |
| uint8x8_t nearb = vld1_u8(in_near + i); |
| int16x8_t diff = vreinterpretq_s16_u16(vsubl_u8(farb, nearb)); |
| int16x8_t nears = vreinterpretq_s16_u16(vshll_n_u8(nearb, 2)); |
| int16x8_t curr = vaddq_s16(nears, diff); // current row |
| |
| // horizontal filter works the same based on shifted vers of current |
| // row. "prev" is current row shifted right by 1 pixel; we need to |
| // insert the previous pixel value (from t1). |
| // "next" is current row shifted left by 1 pixel, with first pixel |
| // of next block of 8 pixels added in. |
| int16x8_t prv0 = vextq_s16(curr, curr, 7); |
| int16x8_t nxt0 = vextq_s16(curr, curr, 1); |
| int16x8_t prev = vsetq_lane_s16(t1, prv0, 0); |
| int16x8_t next = vsetq_lane_s16(3*in_near[i+8] + in_far[i+8], nxt0, 7); |
| |
| // horizontal filter, polyphase implementation since it's convenient: |
| // even pixels = 3*cur + prev = cur*4 + (prev - cur) |
| // odd pixels = 3*cur + next = cur*4 + (next - cur) |
| // note the shared term. |
| int16x8_t curs = vshlq_n_s16(curr, 2); |
| int16x8_t prvd = vsubq_s16(prev, curr); |
| int16x8_t nxtd = vsubq_s16(next, curr); |
| int16x8_t even = vaddq_s16(curs, prvd); |
| int16x8_t odd = vaddq_s16(curs, nxtd); |
| |
| // undo scaling and round, then store with even/odd phases interleaved |
| uint8x8x2_t o; |
| o.val[0] = vqrshrun_n_s16(even, 4); |
| o.val[1] = vqrshrun_n_s16(odd, 4); |
| vst2_u8(out + i*2, o); |
| #endif |
| |
| // "previous" value for next iter |
| t1 = 3*in_near[i+7] + in_far[i+7]; |
| } |
| |
| t0 = t1; |
| t1 = 3*in_near[i] + in_far[i]; |
| out[i*2] = stbi__div16(3*t1 + t0 + 8); |
| |
| for (++i; i < w; ++i) { |
| t0 = t1; |
| t1 = 3*in_near[i]+in_far[i]; |
| out[i*2-1] = stbi__div16(3*t0 + t1 + 8); |
| out[i*2 ] = stbi__div16(3*t1 + t0 + 8); |
| } |
| out[w*2-1] = stbi__div4(t1+2); |
| |
| STBI_NOTUSED(hs); |
| |
| return out; |
| } |
| #endif |
| |
| static stbi_uc *stbi__resample_row_generic(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs) |
| { |
| // resample with nearest-neighbor |
| int i,j; |
| STBI_NOTUSED(in_far); |
| for (i=0; i < w; ++i) |
| for (j=0; j < hs; ++j) |
| out[i*hs+j] = in_near[i]; |
| return out; |
| } |
| |
| // this is a reduced-precision calculation of YCbCr-to-RGB introduced |
| // to make sure the code produces the same results in both SIMD and scalar |
| #define stbi__float2fixed(x) (((int) ((x) * 4096.0f + 0.5f)) << 8) |
| static void stbi__YCbCr_to_RGB_row(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step) |
| { |
| int i; |
| for (i=0; i < count; ++i) { |
| int y_fixed = (y[i] << 20) + (1<<19); // rounding |
| int r,g,b; |
| int cr = pcr[i] - 128; |
| int cb = pcb[i] - 128; |
| r = y_fixed + cr* stbi__float2fixed(1.40200f); |
| g = y_fixed + (cr*-stbi__float2fixed(0.71414f)) + ((cb*-stbi__float2fixed(0.34414f)) & 0xffff0000); |
| b = y_fixed + cb* stbi__float2fixed(1.77200f); |
| r >>= 20; |
| g >>= 20; |
| b >>= 20; |
| if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; } |
| if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; } |
| if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; } |
| out[0] = (stbi_uc)r; |
| out[1] = (stbi_uc)g; |
| out[2] = (stbi_uc)b; |
| out[3] = 255; |
| out += step; |
| } |
| } |
| |
| #if defined(STBI_SSE2) || defined(STBI_NEON) |
| static void stbi__YCbCr_to_RGB_simd(stbi_uc *out, stbi_uc const *y, stbi_uc const *pcb, stbi_uc const *pcr, int count, int step) |
| { |
| int i = 0; |
| |
| #ifdef STBI_SSE2 |
| // step == 3 is pretty ugly on the final interleave, and i'm not convinced |
| // it's useful in practice (you wouldn't use it for textures, for example). |
| // so just accelerate step == 4 case. |
| if (step == 4) { |
| // this is a fairly straightforward implementation and not super-optimized. |
| __m128i signflip = _mm_set1_epi8(-0x80); |
| __m128i cr_const0 = _mm_set1_epi16( (short) ( 1.40200f*4096.0f+0.5f)); |
| __m128i cr_const1 = _mm_set1_epi16( - (short) ( 0.71414f*4096.0f+0.5f)); |
| __m128i cb_const0 = _mm_set1_epi16( - (short) ( 0.34414f*4096.0f+0.5f)); |
| __m128i cb_const1 = _mm_set1_epi16( (short) ( 1.77200f*4096.0f+0.5f)); |
| __m128i y_bias = _mm_set1_epi8((char) (unsigned char) 128); |
| __m128i xw = _mm_set1_epi16(255); // alpha channel |
| |
| for (; i+7 < count; i += 8) { |
| // load |
| __m128i y_bytes = _mm_loadl_epi64((__m128i *) (y+i)); |
| __m128i cr_bytes = _mm_loadl_epi64((__m128i *) (pcr+i)); |
| __m128i cb_bytes = _mm_loadl_epi64((__m128i *) (pcb+i)); |
| __m128i cr_biased = _mm_xor_si128(cr_bytes, signflip); // -128 |
| __m128i cb_biased = _mm_xor_si128(cb_bytes, signflip); // -128 |
| |
| // unpack to short (and left-shift cr, cb by 8) |
| __m128i yw = _mm_unpacklo_epi8(y_bias, y_bytes); |
| __m128i crw = _mm_unpacklo_epi8(_mm_setzero_si128(), cr_biased); |
| __m128i cbw = _mm_unpacklo_epi8(_mm_setzero_si128(), cb_biased); |
| |
| // color transform |
| __m128i yws = _mm_srli_epi16(yw, 4); |
| __m128i cr0 = _mm_mulhi_epi16(cr_const0, crw); |
| __m128i cb0 = _mm_mulhi_epi16(cb_const0, cbw); |
| __m128i cb1 = _mm_mulhi_epi16(cbw, cb_const1); |
| __m128i cr1 = _mm_mulhi_epi16(crw, cr_const1); |
| __m128i rws = _mm_add_epi16(cr0, yws); |
| __m128i gwt = _mm_add_epi16(cb0, yws); |
| __m128i bws = _mm_add_epi16(yws, cb1); |
| __m128i gws = _mm_add_epi16(gwt, cr1); |
| |
| // descale |
| __m128i rw = _mm_srai_epi16(rws, 4); |
| __m128i bw = _mm_srai_epi16(bws, 4); |
| __m128i gw = _mm_srai_epi16(gws, 4); |
| |
| // back to byte, set up for transpose |
| __m128i brb = _mm_packus_epi16(rw, bw); |
| __m128i gxb = _mm_packus_epi16(gw, xw); |
| |
| // transpose to interleave channels |
| __m128i t0 = _mm_unpacklo_epi8(brb, gxb); |
| __m128i t1 = _mm_unpackhi_epi8(brb, gxb); |
| __m128i o0 = _mm_unpacklo_epi16(t0, t1); |
| __m128i o1 = _mm_unpackhi_epi16(t0, t1); |
| |
| // store |
| _mm_storeu_si128((__m128i *) (out + 0), o0); |
| _mm_storeu_si128((__m128i *) (out + 16), o1); |
| out += 32; |
| } |
| } |
| #endif |
| |
| #ifdef STBI_NEON |
| // in this version, step=3 support would be easy to add. but is there demand? |
| if (step == 4) { |
| // this is a fairly straightforward implementation and not super-optimized. |
| uint8x8_t signflip = vdup_n_u8(0x80); |
| int16x8_t cr_const0 = vdupq_n_s16( (short) ( 1.40200f*4096.0f+0.5f)); |
| int16x8_t cr_const1 = vdupq_n_s16( - (short) ( 0.71414f*4096.0f+0.5f)); |
| int16x8_t cb_const0 = vdupq_n_s16( - (short) ( 0.34414f*4096.0f+0.5f)); |
| int16x8_t cb_const1 = vdupq_n_s16( (short) ( 1.77200f*4096.0f+0.5f)); |
| |
| for (; i+7 < count; i += 8) { |
| // load |
| uint8x8_t y_bytes = vld1_u8(y + i); |
| uint8x8_t cr_bytes = vld1_u8(pcr + i); |
| uint8x8_t cb_bytes = vld1_u8(pcb + i); |
| int8x8_t cr_biased = vreinterpret_s8_u8(vsub_u8(cr_bytes, signflip)); |
| int8x8_t cb_biased = vreinterpret_s8_u8(vsub_u8(cb_bytes, signflip)); |
| |
| // expand to s16 |
| int16x8_t yws = vreinterpretq_s16_u16(vshll_n_u8(y_bytes, 4)); |
| int16x8_t crw = vshll_n_s8(cr_biased, 7); |
| int16x8_t cbw = vshll_n_s8(cb_biased, 7); |
| |
| // color transform |
| int16x8_t cr0 = vqdmulhq_s16(crw, cr_const0); |
| int16x8_t cb0 = vqdmulhq_s16(cbw, cb_const0); |
| int16x8_t cr1 = vqdmulhq_s16(crw, cr_const1); |
| int16x8_t cb1 = vqdmulhq_s16(cbw, cb_const1); |
| int16x8_t rws = vaddq_s16(yws, cr0); |
| int16x8_t gws = vaddq_s16(vaddq_s16(yws, cb0), cr1); |
| int16x8_t bws = vaddq_s16(yws, cb1); |
| |
| // undo scaling, round, convert to byte |
| uint8x8x4_t o; |
| o.val[0] = vqrshrun_n_s16(rws, 4); |
| o.val[1] = vqrshrun_n_s16(gws, 4); |
| o.val[2] = vqrshrun_n_s16(bws, 4); |
| o.val[3] = vdup_n_u8(255); |
| |
| // store, interleaving r/g/b/a |
| vst4_u8(out, o); |
| out += 8*4; |
| } |
| } |
| #endif |
| |
| for (; i < count; ++i) { |
| int y_fixed = (y[i] << 20) + (1<<19); // rounding |
| int r,g,b; |
| int cr = pcr[i] - 128; |
| int cb = pcb[i] - 128; |
| r = y_fixed + cr* stbi__float2fixed(1.40200f); |
| g = y_fixed + cr*-stbi__float2fixed(0.71414f) + ((cb*-stbi__float2fixed(0.34414f)) & 0xffff0000); |
| b = y_fixed + cb* stbi__float2fixed(1.77200f); |
| r >>= 20; |
| g >>= 20; |
| b >>= 20; |
| if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; } |
| if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; } |
| if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; } |
| out[0] = (stbi_uc)r; |
| out[1] = (stbi_uc)g; |
| out[2] = (stbi_uc)b; |
| out[3] = 255; |
| out += step; |
| } |
| } |
| #endif |
| |
| // set up the kernels |
| static void stbi__setup_jpeg(stbi__jpeg *j) |
| { |
| j->idct_block_kernel = stbi__idct_block; |
| j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_row; |
| j->resample_row_hv_2_kernel = stbi__resample_row_hv_2; |
| |
| #ifdef STBI_SSE2 |
| if (stbi__sse2_available()) { |
| j->idct_block_kernel = stbi__idct_simd; |
| j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd; |
| j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd; |
| } |
| #endif |
| |
| #ifdef STBI_NEON |
| j->idct_block_kernel = stbi__idct_simd; |
| j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd; |
| j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd; |
| #endif |
| } |
| |
| // clean up the temporary component buffers |
| static void stbi__cleanup_jpeg(stbi__jpeg *j) |
| { |
| stbi__free_jpeg_components(j, j->s->img_n, 0); |
| } |
| |
| typedef struct |
| { |
| resample_row_func resample; |
| stbi_uc *line0,*line1; |
| int hs,vs; // expansion factor in each axis |
| int w_lores; // horizontal pixels pre-expansion |
| int ystep; // how far through vertical expansion we are |
| int ypos; // which pre-expansion row we're on |
| } stbi__resample; |
| |
| // fast 0..255 * 0..255 => 0..255 rounded multiplication |
| static stbi_uc stbi__blinn_8x8(stbi_uc x, stbi_uc y) |
| { |
| unsigned int t = x*y + 128; |
| return (stbi_uc) ((t + (t >>8)) >> 8); |
| } |
| |
| static stbi_uc *load_jpeg_image(stbi__jpeg *z, int *out_x, int *out_y, int *comp, int req_comp) |
| { |
| int n, decode_n, is_rgb; |
| z->s->img_n = 0; // make stbi__cleanup_jpeg safe |
| |
| // validate req_comp |
| if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error"); |
| |
| // load a jpeg image from whichever source, but leave in YCbCr format |
| if (!stbi__decode_jpeg_image(z)) { stbi__cleanup_jpeg(z); return NULL; } |
| |
| // determine actual number of components to generate |
| n = req_comp ? req_comp : z->s->img_n >= 3 ? 3 : 1; |
| |
| is_rgb = z->s->img_n == 3 && (z->rgb == 3 || (z->app14_color_transform == 0 && !z->jfif)); |
| |
| if (z->s->img_n == 3 && n < 3 && !is_rgb) |
| decode_n = 1; |
| else |
| decode_n = z->s->img_n; |
| |
| // resample and color-convert |
| { |
| int k; |
| unsigned int i,j; |
| stbi_uc *output; |
| stbi_uc *coutput[4]; |
| |
| stbi__resample res_comp[4]; |
| |
| for (k=0; k < decode_n; ++k) { |
| stbi__resample *r = &res_comp[k]; |
| |
| // allocate line buffer big enough for upsampling off the edges |
| // with upsample factor of 4 |
| z->img_comp[k].linebuf = (stbi_uc *) stbi__malloc(z->s->img_x + 3); |
| if (!z->img_comp[k].linebuf) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); } |
| |
| r->hs = z->img_h_max / z->img_comp[k].h; |
| r->vs = z->img_v_max / z->img_comp[k].v; |
| r->ystep = r->vs >> 1; |
| r->w_lores = (z->s->img_x + r->hs-1) / r->hs; |
| r->ypos = 0; |
| r->line0 = r->line1 = z->img_comp[k].data; |
| |
| if (r->hs == 1 && r->vs == 1) r->resample = resample_row_1; |
| else if (r->hs == 1 && r->vs == 2) r->resample = stbi__resample_row_v_2; |
| else if (r->hs == 2 && r->vs == 1) r->resample = stbi__resample_row_h_2; |
| else if (r->hs == 2 && r->vs == 2) r->resample = z->resample_row_hv_2_kernel; |
| else r->resample = stbi__resample_row_generic; |
| } |
| |
| // can't error after this so, this is safe |
| output = (stbi_uc *) stbi__malloc_mad3(n, z->s->img_x, z->s->img_y, 1); |
| if (!output) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); } |
| |
| // now go ahead and resample |
| for (j=0; j < z->s->img_y; ++j) { |
| stbi_uc *out = output + n * z->s->img_x * j; |
| for (k=0; k < decode_n; ++k) { |
| stbi__resample *r = &res_comp[k]; |
| int y_bot = r->ystep >= (r->vs >> 1); |
| coutput[k] = r->resample(z->img_comp[k].linebuf, |
| y_bot ? r->line1 : r->line0, |
| y_bot ? r->line0 : r->line1, |
| r->w_lores, r->hs); |
| if (++r->ystep >= r->vs) { |
| r->ystep = 0; |
| r->line0 = r->line1; |
| if (++r->ypos < z->img_comp[k].y) |
| r->line1 += z->img_comp[k].w2; |
| } |
| } |
| if (n >= 3) { |
| stbi_uc *y = coutput[0]; |
| if (z->s->img_n == 3) { |
| if (is_rgb) { |
| for (i=0; i < z->s->img_x; ++i) { |
| out[0] = y[i]; |
| out[1] = coutput[1][i]; |
| out[2] = coutput[2][i]; |
| out[3] = 255; |
| out += n; |
| } |
| } else { |
| z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n); |
| } |
| } else if (z->s->img_n == 4) { |
| if (z->app14_color_transform == 0) { // CMYK |
| for (i=0; i < z->s->img_x; ++i) { |
| stbi_uc m = coutput[3][i]; |
| out[0] = stbi__blinn_8x8(coutput[0][i], m); |
| out[1] = stbi__blinn_8x8(coutput[1][i], m); |
| out[2] = stbi__blinn_8x8(coutput[2][i], m); |
| out[3] = 255; |
| out += n; |
| } |
| } else if (z->app14_color_transform == 2) { // YCCK |
| z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n); |
| for (i=0; i < z->s->img_x; ++i) { |
| stbi_uc m = coutput[3][i]; |
| out[0] = stbi__blinn_8x8(255 - out[0], m); |
| out[1] = stbi__blinn_8x8(255 - out[1], m); |
| out[2] = stbi__blinn_8x8(255 - out[2], m); |
| out += n; |
| } |
| } else { // YCbCr + alpha? Ignore the fourth channel for now |
| z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n); |
| } |
| } else |
| for (i=0; i < z->s->img_x; ++i) { |
| out[0] = out[1] = out[2] = y[i]; |
| out[3] = 255; // not used if n==3 |
| out += n; |
| } |
| } else { |
| if (is_rgb) { |
| if (n == 1) |
| for (i=0; i < z->s->img_x; ++i) |
| *out++ = stbi__compute_y(coutput[0][i], coutput[1][i], coutput[2][i]); |
| else { |
| for (i=0; i < z->s->img_x; ++i, out += 2) { |
| out[0] = stbi__compute_y(coutput[0][i], coutput[1][i], coutput[2][i]); |
| out[1] = 255; |
| } |
| } |
| } else if (z->s->img_n == 4 && z->app14_color_transform == 0) { |
| for (i=0; i < z->s->img_x; ++i) { |
| stbi_uc m = coutput[3][i]; |
| stbi_uc r = stbi__blinn_8x8(coutput[0][i], m); |
| stbi_uc g = stbi__blinn_8x8(coutput[1][i], m); |
| stbi_uc b = stbi__blinn_8x8(coutput[2][i], m); |
| out[0] = stbi__compute_y(r, g, b); |
| out[1] = 255; |
| out += n; |
| } |
| } else if (z->s->img_n == 4 && z->app14_color_transform == 2) { |
| for (i=0; i < z->s->img_x; ++i) { |
| out[0] = stbi__blinn_8x8(255 - coutput[0][i], coutput[3][i]); |
| out[1] = 255; |
| out += n; |
| } |
| } else { |
| stbi_uc *y = coutput[0]; |
| if (n == 1) |
| for (i=0; i < z->s->img_x; ++i) out[i] = y[i]; |
| else |
| for (i=0; i < z->s->img_x; ++i) { *out++ = y[i]; *out++ = 255; } |
| } |
| } |
| } |
| stbi__cleanup_jpeg(z); |
| *out_x = z->s->img_x; |
| *out_y = z->s->img_y; |
| if (comp) *comp = z->s->img_n >= 3 ? 3 : 1; // report original components, not output |
| return output; |
| } |
| } |
| |
| static void *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri) |
| { |
| unsigned char* result; |
| stbi__jpeg* j = (stbi__jpeg*) stbi__malloc(sizeof(stbi__jpeg)); |
| STBI_NOTUSED(ri); |
| j->s = s; |
| stbi__setup_jpeg(j); |
| result = load_jpeg_image(j, x,y,comp,req_comp); |
| STBI_FREE(j); |
| return result; |
| } |
| |
| static int stbi__jpeg_test(stbi__context *s) |
| { |
| int r; |
| stbi__jpeg* j = (stbi__jpeg*)stbi__malloc(sizeof(stbi__jpeg)); |
| j->s = s; |
| stbi__setup_jpeg(j); |
| r = stbi__decode_jpeg_header(j, STBI__SCAN_type); |
| stbi__rewind(s); |
| STBI_FREE(j); |
| return r; |
| } |
| |
| static int stbi__jpeg_info_raw(stbi__jpeg *j, int *x, int *y, int *comp) |
| { |
| if (!stbi__decode_jpeg_header(j, STBI__SCAN_header)) { |
| stbi__rewind( j->s ); |
| return 0; |
| } |
| if (x) *x = j->s->img_x; |
| if (y) *y = j->s->img_y; |
| if (comp) *comp = j->s->img_n >= 3 ? 3 : 1; |
| return 1; |
| } |
| |
| static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| int result; |
| stbi__jpeg* j = (stbi__jpeg*) (stbi__malloc(sizeof(stbi__jpeg))); |
| j->s = s; |
| result = stbi__jpeg_info_raw(j, x, y, comp); |
| STBI_FREE(j); |
| return result; |
| } |
| #endif |
| |
| // public domain zlib decode v0.2 Sean Barrett 2006-11-18 |
| // simple implementation |
| // - all input must be provided in an upfront buffer |
| // - all output is written to a single output buffer (can malloc/realloc) |
| // performance |
| // - fast huffman |
| |
| #ifndef STBI_NO_ZLIB |
| |
| // fast-way is faster to check than jpeg huffman, but slow way is slower |
| #define STBI__ZFAST_BITS 9 // accelerate all cases in default tables |
| #define STBI__ZFAST_MASK ((1 << STBI__ZFAST_BITS) - 1) |
| |
| // zlib-style huffman encoding |
| // (jpegs packs from left, zlib from right, so can't share code) |
| typedef struct |
| { |
| stbi__uint16 fast[1 << STBI__ZFAST_BITS]; |
| stbi__uint16 firstcode[16]; |
| int maxcode[17]; |
| stbi__uint16 firstsymbol[16]; |
| stbi_uc size[288]; |
| stbi__uint16 value[288]; |
| } stbi__zhuffman; |
| |
| stbi_inline static int stbi__bitreverse16(int n) |
| { |
| n = ((n & 0xAAAA) >> 1) | ((n & 0x5555) << 1); |
| n = ((n & 0xCCCC) >> 2) | ((n & 0x3333) << 2); |
| n = ((n & 0xF0F0) >> 4) | ((n & 0x0F0F) << 4); |
| n = ((n & 0xFF00) >> 8) | ((n & 0x00FF) << 8); |
| return n; |
| } |
| |
| stbi_inline static int stbi__bit_reverse(int v, int bits) |
| { |
| STBI_ASSERT(bits <= 16); |
| // to bit reverse n bits, reverse 16 and shift |
| // e.g. 11 bits, bit reverse and shift away 5 |
| return stbi__bitreverse16(v) >> (16-bits); |
| } |
| |
| static int stbi__zbuild_huffman(stbi__zhuffman *z, const stbi_uc *sizelist, int num) |
| { |
| int i,k=0; |
| int code, next_code[16], sizes[17]; |
| |
| // DEFLATE spec for generating codes |
| memset(sizes, 0, sizeof(sizes)); |
| memset(z->fast, 0, sizeof(z->fast)); |
| for (i=0; i < num; ++i) |
| ++sizes[sizelist[i]]; |
| sizes[0] = 0; |
| for (i=1; i < 16; ++i) |
| if (sizes[i] > (1 << i)) |
| return stbi__err("bad sizes", "Corrupt PNG"); |
| code = 0; |
| for (i=1; i < 16; ++i) { |
| next_code[i] = code; |
| z->firstcode[i] = (stbi__uint16) code; |
| z->firstsymbol[i] = (stbi__uint16) k; |
| code = (code + sizes[i]); |
| if (sizes[i]) |
| if (code-1 >= (1 << i)) return stbi__err("bad codelengths","Corrupt PNG"); |
| z->maxcode[i] = code << (16-i); // preshift for inner loop |
| code <<= 1; |
| k += sizes[i]; |
| } |
| z->maxcode[16] = 0x10000; // sentinel |
| for (i=0; i < num; ++i) { |
| int s = sizelist[i]; |
| if (s) { |
| int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s]; |
| stbi__uint16 fastv = (stbi__uint16) ((s << 9) | i); |
| z->size [c] = (stbi_uc ) s; |
| z->value[c] = (stbi__uint16) i; |
| if (s <= STBI__ZFAST_BITS) { |
| int j = stbi__bit_reverse(next_code[s],s); |
| while (j < (1 << STBI__ZFAST_BITS)) { |
| z->fast[j] = fastv; |
| j += (1 << s); |
| } |
| } |
| ++next_code[s]; |
| } |
| } |
| return 1; |
| } |
| |
| // zlib-from-memory implementation for PNG reading |
| // because PNG allows splitting the zlib stream arbitrarily, |
| // and it's annoying structurally to have PNG call ZLIB call PNG, |
| // we require PNG read all the IDATs and combine them into a single |
| // memory buffer |
| |
| typedef struct |
| { |
| stbi_uc *zbuffer, *zbuffer_end; |
| int num_bits; |
| stbi__uint32 code_buffer; |
| |
| char *zout; |
| char *zout_start; |
| char *zout_end; |
| int z_expandable; |
| |
| stbi__zhuffman z_length, z_distance; |
| } stbi__zbuf; |
| |
| stbi_inline static stbi_uc stbi__zget8(stbi__zbuf *z) |
| { |
| if (z->zbuffer >= z->zbuffer_end) return 0; |
| return *z->zbuffer++; |
| } |
| |
| static void stbi__fill_bits(stbi__zbuf *z) |
| { |
| do { |
| STBI_ASSERT(z->code_buffer < (1U << z->num_bits)); |
| z->code_buffer |= (unsigned int) stbi__zget8(z) << z->num_bits; |
| z->num_bits += 8; |
| } while (z->num_bits <= 24); |
| } |
| |
| stbi_inline static unsigned int stbi__zreceive(stbi__zbuf *z, int n) |
| { |
| unsigned int k; |
| if (z->num_bits < n) stbi__fill_bits(z); |
| k = z->code_buffer & ((1 << n) - 1); |
| z->code_buffer >>= n; |
| z->num_bits -= n; |
| return k; |
| } |
| |
| static int stbi__zhuffman_decode_slowpath(stbi__zbuf *a, stbi__zhuffman *z) |
| { |
| int b,s,k; |
| // not resolved by fast table, so compute it the slow way |
| // use jpeg approach, which requires MSbits at top |
| k = stbi__bit_reverse(a->code_buffer, 16); |
| for (s=STBI__ZFAST_BITS+1; ; ++s) |
| if (k < z->maxcode[s]) |
| break; |
| if (s == 16) return -1; // invalid code! |
| // code size is s, so: |
| b = (k >> (16-s)) - z->firstcode[s] + z->firstsymbol[s]; |
| STBI_ASSERT(z->size[b] == s); |
| a->code_buffer >>= s; |
| a->num_bits -= s; |
| return z->value[b]; |
| } |
| |
| stbi_inline static int stbi__zhuffman_decode(stbi__zbuf *a, stbi__zhuffman *z) |
| { |
| int b,s; |
| if (a->num_bits < 16) stbi__fill_bits(a); |
| b = z->fast[a->code_buffer & STBI__ZFAST_MASK]; |
| if (b) { |
| s = b >> 9; |
| a->code_buffer >>= s; |
| a->num_bits -= s; |
| return b & 511; |
| } |
| return stbi__zhuffman_decode_slowpath(a, z); |
| } |
| |
| static int stbi__zexpand(stbi__zbuf *z, char *zout, int n) // need to make room for n bytes |
| { |
| char *q; |
| int cur, limit, old_limit; |
| z->zout = zout; |
| if (!z->z_expandable) return stbi__err("output buffer limit","Corrupt PNG"); |
| cur = (int) (z->zout - z->zout_start); |
| limit = old_limit = (int) (z->zout_end - z->zout_start); |
| while (cur + n > limit) |
| limit *= 2; |
| q = (char *) STBI_REALLOC_SIZED(z->zout_start, old_limit, limit); |
| STBI_NOTUSED(old_limit); |
| if (q == NULL) return stbi__err("outofmem", "Out of memory"); |
| z->zout_start = q; |
| z->zout = q + cur; |
| z->zout_end = q + limit; |
| return 1; |
| } |
| |
| static const int stbi__zlength_base[31] = { |
| 3,4,5,6,7,8,9,10,11,13, |
| 15,17,19,23,27,31,35,43,51,59, |
| 67,83,99,115,131,163,195,227,258,0,0 }; |
| |
| static const int stbi__zlength_extra[31]= |
| { 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 }; |
| |
| static const int stbi__zdist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193, |
| 257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0}; |
| |
| static const int stbi__zdist_extra[32] = |
| { 0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13}; |
| |
| static int stbi__parse_huffman_block(stbi__zbuf *a) |
| { |
| char *zout = a->zout; |
| for(;;) { |
| int z = stbi__zhuffman_decode(a, &a->z_length); |
| if (z < 256) { |
| if (z < 0) return stbi__err("bad huffman code","Corrupt PNG"); // error in huffman codes |
| if (zout >= a->zout_end) { |
| if (!stbi__zexpand(a, zout, 1)) return 0; |
| zout = a->zout; |
| } |
| *zout++ = (char) z; |
| } else { |
| stbi_uc *p; |
| int len,dist; |
| if (z == 256) { |
| a->zout = zout; |
| return 1; |
| } |
| z -= 257; |
| len = stbi__zlength_base[z]; |
| if (stbi__zlength_extra[z]) len += stbi__zreceive(a, stbi__zlength_extra[z]); |
| z = stbi__zhuffman_decode(a, &a->z_distance); |
| if (z < 0) return stbi__err("bad huffman code","Corrupt PNG"); |
| dist = stbi__zdist_base[z]; |
| if (stbi__zdist_extra[z]) dist += stbi__zreceive(a, stbi__zdist_extra[z]); |
| if (zout - a->zout_start < dist) return stbi__err("bad dist","Corrupt PNG"); |
| if (zout + len > a->zout_end) { |
| if (!stbi__zexpand(a, zout, len)) return 0; |
| zout = a->zout; |
| } |
| p = (stbi_uc *) (zout - dist); |
| if (dist == 1) { // run of one byte; common in images. |
| stbi_uc v = *p; |
| if (len) { do *zout++ = v; while (--len); } |
| } else { |
| if (len) { do *zout++ = *p++; while (--len); } |
| } |
| } |
| } |
| } |
| |
| static int stbi__compute_huffman_codes(stbi__zbuf *a) |
| { |
| static const stbi_uc length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 }; |
| stbi__zhuffman z_codelength; |
| stbi_uc lencodes[286+32+137];//padding for maximum single op |
| stbi_uc codelength_sizes[19]; |
| int i,n; |
| |
| int hlit = stbi__zreceive(a,5) + 257; |
| int hdist = stbi__zreceive(a,5) + 1; |
| int hclen = stbi__zreceive(a,4) + 4; |
| int ntot = hlit + hdist; |
| |
| memset(codelength_sizes, 0, sizeof(codelength_sizes)); |
| for (i=0; i < hclen; ++i) { |
| int s = stbi__zreceive(a,3); |
| codelength_sizes[length_dezigzag[i]] = (stbi_uc) s; |
| } |
| if (!stbi__zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0; |
| |
| n = 0; |
| while (n < ntot) { |
| int c = stbi__zhuffman_decode(a, &z_codelength); |
| if (c < 0 || c >= 19) return stbi__err("bad codelengths", "Corrupt PNG"); |
| if (c < 16) |
| lencodes[n++] = (stbi_uc) c; |
| else { |
| stbi_uc fill = 0; |
| if (c == 16) { |
| c = stbi__zreceive(a,2)+3; |
| if (n == 0) return stbi__err("bad codelengths", "Corrupt PNG"); |
| fill = lencodes[n-1]; |
| } else if (c == 17) |
| c = stbi__zreceive(a,3)+3; |
| else { |
| STBI_ASSERT(c == 18); |
| c = stbi__zreceive(a,7)+11; |
| } |
| if (ntot - n < c) return stbi__err("bad codelengths", "Corrupt PNG"); |
| memset(lencodes+n, fill, c); |
| n += c; |
| } |
| } |
| if (n != ntot) return stbi__err("bad codelengths","Corrupt PNG"); |
| if (!stbi__zbuild_huffman(&a->z_length, lencodes, hlit)) return 0; |
| if (!stbi__zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0; |
| return 1; |
| } |
| |
| static int stbi__parse_uncompressed_block(stbi__zbuf *a) |
| { |
| stbi_uc header[4]; |
| int len,nlen,k; |
| if (a->num_bits & 7) |
| stbi__zreceive(a, a->num_bits & 7); // discard |
| // drain the bit-packed data into header |
| k = 0; |
| while (a->num_bits > 0) { |
| header[k++] = (stbi_uc) (a->code_buffer & 255); // suppress MSVC run-time check |
| a->code_buffer >>= 8; |
| a->num_bits -= 8; |
| } |
| STBI_ASSERT(a->num_bits == 0); |
| // now fill header the normal way |
| while (k < 4) |
| header[k++] = stbi__zget8(a); |
| len = header[1] * 256 + header[0]; |
| nlen = header[3] * 256 + header[2]; |
| if (nlen != (len ^ 0xffff)) return stbi__err("zlib corrupt","Corrupt PNG"); |
| if (a->zbuffer + len > a->zbuffer_end) return stbi__err("read past buffer","Corrupt PNG"); |
| if (a->zout + len > a->zout_end) |
| if (!stbi__zexpand(a, a->zout, len)) return 0; |
| memcpy(a->zout, a->zbuffer, len); |
| a->zbuffer += len; |
| a->zout += len; |
| return 1; |
| } |
| |
| static int stbi__parse_zlib_header(stbi__zbuf *a) |
| { |
| int cmf = stbi__zget8(a); |
| int cm = cmf & 15; |
| /* int cinfo = cmf >> 4; */ |
| int flg = stbi__zget8(a); |
| if ((cmf*256+flg) % 31 != 0) return stbi__err("bad zlib header","Corrupt PNG"); // zlib spec |
| if (flg & 32) return stbi__err("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png |
| if (cm != 8) return stbi__err("bad compression","Corrupt PNG"); // DEFLATE required for png |
| // window = 1 << (8 + cinfo)... but who cares, we fully buffer output |
| return 1; |
| } |
| |
| static const stbi_uc stbi__zdefault_length[288] = |
| { |
| 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, |
| 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, |
| 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, |
| 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, |
| 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, |
| 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, |
| 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, |
| 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, |
| 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8 |
| }; |
| static const stbi_uc stbi__zdefault_distance[32] = |
| { |
| 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5 |
| }; |
| /* |
| Init algorithm: |
| { |
| int i; // use <= to match clearly with spec |
| for (i=0; i <= 143; ++i) stbi__zdefault_length[i] = 8; |
| for ( ; i <= 255; ++i) stbi__zdefault_length[i] = 9; |
| for ( ; i <= 279; ++i) stbi__zdefault_length[i] = 7; |
| for ( ; i <= 287; ++i) stbi__zdefault_length[i] = 8; |
| |
| for (i=0; i <= 31; ++i) stbi__zdefault_distance[i] = 5; |
| } |
| */ |
| |
| static int stbi__parse_zlib(stbi__zbuf *a, int parse_header) |
| { |
| int final, type; |
| if (parse_header) |
| if (!stbi__parse_zlib_header(a)) return 0; |
| a->num_bits = 0; |
| a->code_buffer = 0; |
| do { |
| final = stbi__zreceive(a,1); |
| type = stbi__zreceive(a,2); |
| if (type == 0) { |
| if (!stbi__parse_uncompressed_block(a)) return 0; |
| } else if (type == 3) { |
| return 0; |
| } else { |
| if (type == 1) { |
| // use fixed code lengths |
| if (!stbi__zbuild_huffman(&a->z_length , stbi__zdefault_length , 288)) return 0; |
| if (!stbi__zbuild_huffman(&a->z_distance, stbi__zdefault_distance, 32)) return 0; |
| } else { |
| if (!stbi__compute_huffman_codes(a)) return 0; |
| } |
| if (!stbi__parse_huffman_block(a)) return 0; |
| } |
| } while (!final); |
| return 1; |
| } |
| |
| static int stbi__do_zlib(stbi__zbuf *a, char *obuf, int olen, int exp, int parse_header) |
| { |
| a->zout_start = obuf; |
| a->zout = obuf; |
| a->zout_end = obuf + olen; |
| a->z_expandable = exp; |
| |
| return stbi__parse_zlib(a, parse_header); |
| } |
| |
| STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen) |
| { |
| stbi__zbuf a; |
| char *p = (char *) stbi__malloc(initial_size); |
| if (p == NULL) return NULL; |
| a.zbuffer = (stbi_uc *) buffer; |
| a.zbuffer_end = (stbi_uc *) buffer + len; |
| if (stbi__do_zlib(&a, p, initial_size, 1, 1)) { |
| if (outlen) *outlen = (int) (a.zout - a.zout_start); |
| return a.zout_start; |
| } else { |
| STBI_FREE(a.zout_start); |
| return NULL; |
| } |
| } |
| |
| STBIDEF char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen) |
| { |
| return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen); |
| } |
| |
| STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header) |
| { |
| stbi__zbuf a; |
| char *p = (char *) stbi__malloc(initial_size); |
| if (p == NULL) return NULL; |
| a.zbuffer = (stbi_uc *) buffer; |
| a.zbuffer_end = (stbi_uc *) buffer + len; |
| if (stbi__do_zlib(&a, p, initial_size, 1, parse_header)) { |
| if (outlen) *outlen = (int) (a.zout - a.zout_start); |
| return a.zout_start; |
| } else { |
| STBI_FREE(a.zout_start); |
| return NULL; |
| } |
| } |
| |
| STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen) |
| { |
| stbi__zbuf a; |
| a.zbuffer = (stbi_uc *) ibuffer; |
| a.zbuffer_end = (stbi_uc *) ibuffer + ilen; |
| if (stbi__do_zlib(&a, obuffer, olen, 0, 1)) |
| return (int) (a.zout - a.zout_start); |
| else |
| return -1; |
| } |
| |
| STBIDEF char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen) |
| { |
| stbi__zbuf a; |
| char *p = (char *) stbi__malloc(16384); |
| if (p == NULL) return NULL; |
| a.zbuffer = (stbi_uc *) buffer; |
| a.zbuffer_end = (stbi_uc *) buffer+len; |
| if (stbi__do_zlib(&a, p, 16384, 1, 0)) { |
| if (outlen) *outlen = (int) (a.zout - a.zout_start); |
| return a.zout_start; |
| } else { |
| STBI_FREE(a.zout_start); |
| return NULL; |
| } |
| } |
| |
| STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen) |
| { |
| stbi__zbuf a; |
| a.zbuffer = (stbi_uc *) ibuffer; |
| a.zbuffer_end = (stbi_uc *) ibuffer + ilen; |
| if (stbi__do_zlib(&a, obuffer, olen, 0, 0)) |
| return (int) (a.zout - a.zout_start); |
| else |
| return -1; |
| } |
| #endif |
| |
| // public domain "baseline" PNG decoder v0.10 Sean Barrett 2006-11-18 |
| // simple implementation |
| // - only 8-bit samples |
| // - no CRC checking |
| // - allocates lots of intermediate memory |
| // - avoids problem of streaming data between subsystems |
| // - avoids explicit window management |
| // performance |
| // - uses stb_zlib, a PD zlib implementation with fast huffman decoding |
| |
| #ifndef STBI_NO_PNG |
| typedef struct |
| { |
| stbi__uint32 length; |
| stbi__uint32 type; |
| } stbi__pngchunk; |
| |
| static stbi__pngchunk stbi__get_chunk_header(stbi__context *s) |
| { |
| stbi__pngchunk c; |
| c.length = stbi__get32be(s); |
| c.type = stbi__get32be(s); |
| return c; |
| } |
| |
| static int stbi__check_png_header(stbi__context *s) |
| { |
| static const stbi_uc png_sig[8] = { 137,80,78,71,13,10,26,10 }; |
| int i; |
| for (i=0; i < 8; ++i) |
| if (stbi__get8(s) != png_sig[i]) return stbi__err("bad png sig","Not a PNG"); |
| return 1; |
| } |
| |
| typedef struct |
| { |
| stbi__context *s; |
| stbi_uc *idata, *expanded, *out; |
| int depth; |
| } stbi__png; |
| |
| |
| enum { |
| STBI__F_none=0, |
| STBI__F_sub=1, |
| STBI__F_up=2, |
| STBI__F_avg=3, |
| STBI__F_paeth=4, |
| // synthetic filters used for first scanline to avoid needing a dummy row of 0s |
| STBI__F_avg_first, |
| STBI__F_paeth_first |
| }; |
| |
| static stbi_uc first_row_filter[5] = |
| { |
| STBI__F_none, |
| STBI__F_sub, |
| STBI__F_none, |
| STBI__F_avg_first, |
| STBI__F_paeth_first |
| }; |
| |
| static int stbi__paeth(int a, int b, int c) |
| { |
| int p = a + b - c; |
| int pa = abs(p-a); |
| int pb = abs(p-b); |
| int pc = abs(p-c); |
| if (pa <= pb && pa <= pc) return a; |
| if (pb <= pc) return b; |
| return c; |
| } |
| |
| static const stbi_uc stbi__depth_scale_table[9] = { 0, 0xff, 0x55, 0, 0x11, 0,0,0, 0x01 }; |
| |
| // create the png data from post-deflated data |
| static int stbi__create_png_image_raw(stbi__png *a, stbi_uc *raw, stbi__uint32 raw_len, int out_n, stbi__uint32 x, stbi__uint32 y, int depth, int color) |
| { |
| int bytes = (depth == 16? 2 : 1); |
| stbi__context *s = a->s; |
| stbi__uint32 i,j,stride = x*out_n*bytes; |
| stbi__uint32 img_len, img_width_bytes; |
| int k; |
| int img_n = s->img_n; // copy it into a local for later |
| |
| int output_bytes = out_n*bytes; |
| int filter_bytes = img_n*bytes; |
| int width = x; |
| |
| STBI_ASSERT(out_n == s->img_n || out_n == s->img_n+1); |
| a->out = (stbi_uc *) stbi__malloc_mad3(x, y, output_bytes, 0); // extra bytes to write off the end into |
| if (!a->out) return stbi__err("outofmem", "Out of memory"); |
| |
| if (!stbi__mad3sizes_valid(img_n, x, depth, 7)) return stbi__err("too large", "Corrupt PNG"); |
| img_width_bytes = (((img_n * x * depth) + 7) >> 3); |
| img_len = (img_width_bytes + 1) * y; |
| |
| // we used to check for exact match between raw_len and img_len on non-interlaced PNGs, |
| // but issue #276 reported a PNG in the wild that had extra data at the end (all zeros), |
| // so just check for raw_len < img_len always. |
| if (raw_len < img_len) return stbi__err("not enough pixels","Corrupt PNG"); |
| |
| for (j=0; j < y; ++j) { |
| stbi_uc *cur = a->out + stride*j; |
| stbi_uc *prior; |
| int filter = *raw++; |
| |
| if (filter > 4) |
| return stbi__err("invalid filter","Corrupt PNG"); |
| |
| if (depth < 8) { |
| STBI_ASSERT(img_width_bytes <= x); |
| cur += x*out_n - img_width_bytes; // store output to the rightmost img_len bytes, so we can decode in place |
| filter_bytes = 1; |
| width = img_width_bytes; |
| } |
| prior = cur - stride; // bugfix: need to compute this after 'cur +=' computation above |
| |
| // if first row, use special filter that doesn't sample previous row |
| if (j == 0) filter = first_row_filter[filter]; |
| |
| // handle first byte explicitly |
| for (k=0; k < filter_bytes; ++k) { |
| switch (filter) { |
| case STBI__F_none : cur[k] = raw[k]; break; |
| case STBI__F_sub : cur[k] = raw[k]; break; |
| case STBI__F_up : cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break; |
| case STBI__F_avg : cur[k] = STBI__BYTECAST(raw[k] + (prior[k]>>1)); break; |
| case STBI__F_paeth : cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(0,prior[k],0)); break; |
| case STBI__F_avg_first : cur[k] = raw[k]; break; |
| case STBI__F_paeth_first: cur[k] = raw[k]; break; |
| } |
| } |
| |
| if (depth == 8) { |
| if (img_n != out_n) |
| cur[img_n] = 255; // first pixel |
| raw += img_n; |
| cur += out_n; |
| prior += out_n; |
| } else if (depth == 16) { |
| if (img_n != out_n) { |
| cur[filter_bytes] = 255; // first pixel top byte |
| cur[filter_bytes+1] = 255; // first pixel bottom byte |
| } |
| raw += filter_bytes; |
| cur += output_bytes; |
| prior += output_bytes; |
| } else { |
| raw += 1; |
| cur += 1; |
| prior += 1; |
| } |
| |
| // this is a little gross, so that we don't switch per-pixel or per-component |
| if (depth < 8 || img_n == out_n) { |
| int nk = (width - 1)*filter_bytes; |
| #define STBI__CASE(f) \ |
| case f: \ |
| for (k=0; k < nk; ++k) |
| switch (filter) { |
| // "none" filter turns into a memcpy here; make that explicit. |
| case STBI__F_none: memcpy(cur, raw, nk); break; |
| STBI__CASE(STBI__F_sub) { cur[k] = STBI__BYTECAST(raw[k] + cur[k-filter_bytes]); } break; |
| STBI__CASE(STBI__F_up) { cur[k] = STBI__BYTECAST(raw[k] + prior[k]); } break; |
| STBI__CASE(STBI__F_avg) { cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k-filter_bytes])>>1)); } break; |
| STBI__CASE(STBI__F_paeth) { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],prior[k],prior[k-filter_bytes])); } break; |
| STBI__CASE(STBI__F_avg_first) { cur[k] = STBI__BYTECAST(raw[k] + (cur[k-filter_bytes] >> 1)); } break; |
| STBI__CASE(STBI__F_paeth_first) { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],0,0)); } break; |
| } |
| #undef STBI__CASE |
| raw += nk; |
| } else { |
| STBI_ASSERT(img_n+1 == out_n); |
| #define STBI__CASE(f) \ |
| case f: \ |
| for (i=x-1; i >= 1; --i, cur[filter_bytes]=255,raw+=filter_bytes,cur+=output_bytes,prior+=output_bytes) \ |
| for (k=0; k < filter_bytes; ++k) |
| switch (filter) { |
| STBI__CASE(STBI__F_none) { cur[k] = raw[k]; } break; |
| STBI__CASE(STBI__F_sub) { cur[k] = STBI__BYTECAST(raw[k] + cur[k- output_bytes]); } break; |
| STBI__CASE(STBI__F_up) { cur[k] = STBI__BYTECAST(raw[k] + prior[k]); } break; |
| STBI__CASE(STBI__F_avg) { cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k- output_bytes])>>1)); } break; |
| STBI__CASE(STBI__F_paeth) { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k- output_bytes],prior[k],prior[k- output_bytes])); } break; |
| STBI__CASE(STBI__F_avg_first) { cur[k] = STBI__BYTECAST(raw[k] + (cur[k- output_bytes] >> 1)); } break; |
| STBI__CASE(STBI__F_paeth_first) { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k- output_bytes],0,0)); } break; |
| } |
| #undef STBI__CASE |
| |
| // the loop above sets the high byte of the pixels' alpha, but for |
| // 16 bit png files we also need the low byte set. we'll do that here. |
| if (depth == 16) { |
| cur = a->out + stride*j; // start at the beginning of the row again |
| for (i=0; i < x; ++i,cur+=output_bytes) { |
| cur[filter_bytes+1] = 255; |
| } |
| } |
| } |
| } |
| |
| // we make a separate pass to expand bits to pixels; for performance, |
| // this could run two scanlines behind the above code, so it won't |
| // intefere with filtering but will still be in the cache. |
| if (depth < 8) { |
| for (j=0; j < y; ++j) { |
| stbi_uc *cur = a->out + stride*j; |
| stbi_uc *in = a->out + stride*j + x*out_n - img_width_bytes; |
| // unpack 1/2/4-bit into a 8-bit buffer. allows us to keep the common 8-bit path optimal at minimal cost for 1/2/4-bit |
| // png guarante byte alignment, if width is not multiple of 8/4/2 we'll decode dummy trailing data that will be skipped in the later loop |
| stbi_uc scale = (color == 0) ? stbi__depth_scale_table[depth] : 1; // scale grayscale values to 0..255 range |
| |
| // note that the final byte might overshoot and write more data than desired. |
| // we can allocate enough data that this never writes out of memory, but it |
| // could also overwrite the next scanline. can it overwrite non-empty data |
| // on the next scanline? yes, consider 1-pixel-wide scanlines with 1-bit-per-pixel. |
| // so we need to explicitly clamp the final ones |
| |
| if (depth == 4) { |
| for (k=x*img_n; k >= 2; k-=2, ++in) { |
| *cur++ = scale * ((*in >> 4) ); |
| *cur++ = scale * ((*in ) & 0x0f); |
| } |
| if (k > 0) *cur++ = scale * ((*in >> 4) ); |
| } else if (depth == 2) { |
| for (k=x*img_n; k >= 4; k-=4, ++in) { |
| *cur++ = scale * ((*in >> 6) ); |
| *cur++ = scale * ((*in >> 4) & 0x03); |
| *cur++ = scale * ((*in >> 2) & 0x03); |
| *cur++ = scale * ((*in ) & 0x03); |
| } |
| if (k > 0) *cur++ = scale * ((*in >> 6) ); |
| if (k > 1) *cur++ = scale * ((*in >> 4) & 0x03); |
| if (k > 2) *cur++ = scale * ((*in >> 2) & 0x03); |
| } else if (depth == 1) { |
| for (k=x*img_n; k >= 8; k-=8, ++in) { |
| *cur++ = scale * ((*in >> 7) ); |
| *cur++ = scale * ((*in >> 6) & 0x01); |
| *cur++ = scale * ((*in >> 5) & 0x01); |
| *cur++ = scale * ((*in >> 4) & 0x01); |
| *cur++ = scale * ((*in >> 3) & 0x01); |
| *cur++ = scale * ((*in >> 2) & 0x01); |
| *cur++ = scale * ((*in >> 1) & 0x01); |
| *cur++ = scale * ((*in ) & 0x01); |
| } |
| if (k > 0) *cur++ = scale * ((*in >> 7) ); |
| if (k > 1) *cur++ = scale * ((*in >> 6) & 0x01); |
| if (k > 2) *cur++ = scale * ((*in >> 5) & 0x01); |
| if (k > 3) *cur++ = scale * ((*in >> 4) & 0x01); |
| if (k > 4) *cur++ = scale * ((*in >> 3) & 0x01); |
| if (k > 5) *cur++ = scale * ((*in >> 2) & 0x01); |
| if (k > 6) *cur++ = scale * ((*in >> 1) & 0x01); |
| } |
| if (img_n != out_n) { |
| int q; |
| // insert alpha = 255 |
| cur = a->out + stride*j; |
| if (img_n == 1) { |
| for (q=x-1; q >= 0; --q) { |
| cur[q*2+1] = 255; |
| cur[q*2+0] = cur[q]; |
| } |
| } else { |
| STBI_ASSERT(img_n == 3); |
| for (q=x-1; q >= 0; --q) { |
| cur[q*4+3] = 255; |
| cur[q*4+2] = cur[q*3+2]; |
| cur[q*4+1] = cur[q*3+1]; |
| cur[q*4+0] = cur[q*3+0]; |
| } |
| } |
| } |
| } |
| } else if (depth == 16) { |
| // force the image data from big-endian to platform-native. |
| // this is done in a separate pass due to the decoding relying |
| // on the data being untouched, but could probably be done |
| // per-line during decode if care is taken. |
| stbi_uc *cur = a->out; |
| stbi__uint16 *cur16 = (stbi__uint16*)cur; |
| |
| for(i=0; i < x*y*out_n; ++i,cur16++,cur+=2) { |
| *cur16 = (cur[0] << 8) | cur[1]; |
| } |
| } |
| |
| return 1; |
| } |
| |
| static int stbi__create_png_image(stbi__png *a, stbi_uc *image_data, stbi__uint32 image_data_len, int out_n, int depth, int color, int interlaced) |
| { |
| int bytes = (depth == 16 ? 2 : 1); |
| int out_bytes = out_n * bytes; |
| stbi_uc *final; |
| int p; |
| if (!interlaced) |
| return stbi__create_png_image_raw(a, image_data, image_data_len, out_n, a->s->img_x, a->s->img_y, depth, color); |
| |
| // de-interlacing |
| final = (stbi_uc *) stbi__malloc_mad3(a->s->img_x, a->s->img_y, out_bytes, 0); |
| for (p=0; p < 7; ++p) { |
| int xorig[] = { 0,4,0,2,0,1,0 }; |
| int yorig[] = { 0,0,4,0,2,0,1 }; |
| int xspc[] = { 8,8,4,4,2,2,1 }; |
| int yspc[] = { 8,8,8,4,4,2,2 }; |
| int i,j,x,y; |
| // pass1_x[4] = 0, pass1_x[5] = 1, pass1_x[12] = 1 |
| x = (a->s->img_x - xorig[p] + xspc[p]-1) / xspc[p]; |
| y = (a->s->img_y - yorig[p] + yspc[p]-1) / yspc[p]; |
| if (x && y) { |
| stbi__uint32 img_len = ((((a->s->img_n * x * depth) + 7) >> 3) + 1) * y; |
| if (!stbi__create_png_image_raw(a, image_data, image_data_len, out_n, x, y, depth, color)) { |
| STBI_FREE(final); |
| return 0; |
| } |
| for (j=0; j < y; ++j) { |
| for (i=0; i < x; ++i) { |
| int out_y = j*yspc[p]+yorig[p]; |
| int out_x = i*xspc[p]+xorig[p]; |
| memcpy(final + out_y*a->s->img_x*out_bytes + out_x*out_bytes, |
| a->out + (j*x+i)*out_bytes, out_bytes); |
| } |
| } |
| STBI_FREE(a->out); |
| image_data += img_len; |
| image_data_len -= img_len; |
| } |
| } |
| a->out = final; |
| |
| return 1; |
| } |
| |
| static int stbi__compute_transparency(stbi__png *z, stbi_uc tc[3], int out_n) |
| { |
| stbi__context *s = z->s; |
| stbi__uint32 i, pixel_count = s->img_x * s->img_y; |
| stbi_uc *p = z->out; |
| |
| // compute color-based transparency, assuming we've |
| // already got 255 as the alpha value in the output |
| STBI_ASSERT(out_n == 2 || out_n == 4); |
| |
| if (out_n == 2) { |
| for (i=0; i < pixel_count; ++i) { |
| p[1] = (p[0] == tc[0] ? 0 : 255); |
| p += 2; |
| } |
| } else { |
| for (i=0; i < pixel_count; ++i) { |
| if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2]) |
| p[3] = 0; |
| p += 4; |
| } |
| } |
| return 1; |
| } |
| |
| static int stbi__compute_transparency16(stbi__png *z, stbi__uint16 tc[3], int out_n) |
| { |
| stbi__context *s = z->s; |
| stbi__uint32 i, pixel_count = s->img_x * s->img_y; |
| stbi__uint16 *p = (stbi__uint16*) z->out; |
| |
| // compute color-based transparency, assuming we've |
| // already got 65535 as the alpha value in the output |
| STBI_ASSERT(out_n == 2 || out_n == 4); |
| |
| if (out_n == 2) { |
| for (i = 0; i < pixel_count; ++i) { |
| p[1] = (p[0] == tc[0] ? 0 : 65535); |
| p += 2; |
| } |
| } else { |
| for (i = 0; i < pixel_count; ++i) { |
| if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2]) |
| p[3] = 0; |
| p += 4; |
| } |
| } |
| return 1; |
| } |
| |
| static int stbi__expand_png_palette(stbi__png *a, stbi_uc *palette, int len, int pal_img_n) |
| { |
| stbi__uint32 i, pixel_count = a->s->img_x * a->s->img_y; |
| stbi_uc *p, *temp_out, *orig = a->out; |
| |
| p = (stbi_uc *) stbi__malloc_mad2(pixel_count, pal_img_n, 0); |
| if (p == NULL) return stbi__err("outofmem", "Out of memory"); |
| |
| // between here and free(out) below, exitting would leak |
| temp_out = p; |
| |
| if (pal_img_n == 3) { |
| for (i=0; i < pixel_count; ++i) { |
| int n = orig[i]*4; |
| p[0] = palette[n ]; |
| p[1] = palette[n+1]; |
| p[2] = palette[n+2]; |
| p += 3; |
| } |
| } else { |
| for (i=0; i < pixel_count; ++i) { |
| int n = orig[i]*4; |
| p[0] = palette[n ]; |
| p[1] = palette[n+1]; |
| p[2] = palette[n+2]; |
| p[3] = palette[n+3]; |
| p += 4; |
| } |
| } |
| STBI_FREE(a->out); |
| a->out = temp_out; |
| |
| STBI_NOTUSED(len); |
| |
| return 1; |
| } |
| |
| static int stbi__unpremultiply_on_load = 0; |
| static int stbi__de_iphone_flag = 0; |
| |
| STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply) |
| { |
| stbi__unpremultiply_on_load = flag_true_if_should_unpremultiply; |
| } |
| |
| STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert) |
| { |
| stbi__de_iphone_flag = flag_true_if_should_convert; |
| } |
| |
| static void stbi__de_iphone(stbi__png *z) |
| { |
| stbi__context *s = z->s; |
| stbi__uint32 i, pixel_count = s->img_x * s->img_y; |
| stbi_uc *p = z->out; |
| |
| if (s->img_out_n == 3) { // convert bgr to rgb |
| for (i=0; i < pixel_count; ++i) { |
| stbi_uc t = p[0]; |
| p[0] = p[2]; |
| p[2] = t; |
| p += 3; |
| } |
| } else { |
| STBI_ASSERT(s->img_out_n == 4); |
| if (stbi__unpremultiply_on_load) { |
| // convert bgr to rgb and unpremultiply |
| for (i=0; i < pixel_count; ++i) { |
| stbi_uc a = p[3]; |
| stbi_uc t = p[0]; |
| if (a) { |
| stbi_uc half = a / 2; |
| p[0] = (p[2] * 255 + half) / a; |
| p[1] = (p[1] * 255 + half) / a; |
| p[2] = ( t * 255 + half) / a; |
| } else { |
| p[0] = p[2]; |
| p[2] = t; |
| } |
| p += 4; |
| } |
| } else { |
| // convert bgr to rgb |
| for (i=0; i < pixel_count; ++i) { |
| stbi_uc t = p[0]; |
| p[0] = p[2]; |
| p[2] = t; |
| p += 4; |
| } |
| } |
| } |
| } |
| |
| #define STBI__PNG_TYPE(a,b,c,d) (((unsigned) (a) << 24) + ((unsigned) (b) << 16) + ((unsigned) (c) << 8) + (unsigned) (d)) |
| |
| static int stbi__parse_png_file(stbi__png *z, int scan, int req_comp) |
| { |
| stbi_uc palette[1024], pal_img_n=0; |
| stbi_uc has_trans=0, tc[3]={0}; |
| stbi__uint16 tc16[3]; |
| stbi__uint32 ioff=0, idata_limit=0, i, pal_len=0; |
| int first=1,k,interlace=0, color=0, is_iphone=0; |
| stbi__context *s = z->s; |
| |
| z->expanded = NULL; |
| z->idata = NULL; |
| z->out = NULL; |
| |
| if (!stbi__check_png_header(s)) return 0; |
| |
| if (scan == STBI__SCAN_type) return 1; |
| |
| for (;;) { |
| stbi__pngchunk c = stbi__get_chunk_header(s); |
| switch (c.type) { |
| case STBI__PNG_TYPE('C','g','B','I'): |
| is_iphone = 1; |
| stbi__skip(s, c.length); |
| break; |
| case STBI__PNG_TYPE('I','H','D','R'): { |
| int comp,filter; |
| if (!first) return stbi__err("multiple IHDR","Corrupt PNG"); |
| first = 0; |
| if (c.length != 13) return stbi__err("bad IHDR len","Corrupt PNG"); |
| s->img_x = stbi__get32be(s); if (s->img_x > (1 << 24)) return stbi__err("too large","Very large image (corrupt?)"); |
| s->img_y = stbi__get32be(s); if (s->img_y > (1 << 24)) return stbi__err("too large","Very large image (corrupt?)"); |
| z->depth = stbi__get8(s); if (z->depth != 1 && z->depth != 2 && z->depth != 4 && z->depth != 8 && z->depth != 16) return stbi__err("1/2/4/8/16-bit only","PNG not supported: 1/2/4/8/16-bit only"); |
| color = stbi__get8(s); if (color > 6) return stbi__err("bad ctype","Corrupt PNG"); |
| if (color == 3 && z->depth == 16) return stbi__err("bad ctype","Corrupt PNG"); |
| if (color == 3) pal_img_n = 3; else if (color & 1) return stbi__err("bad ctype","Corrupt PNG"); |
| comp = stbi__get8(s); if (comp) return stbi__err("bad comp method","Corrupt PNG"); |
| filter= stbi__get8(s); if (filter) return stbi__err("bad filter method","Corrupt PNG"); |
| interlace = stbi__get8(s); if (interlace>1) return stbi__err("bad interlace method","Corrupt PNG"); |
| if (!s->img_x || !s->img_y) return stbi__err("0-pixel image","Corrupt PNG"); |
| if (!pal_img_n) { |
| s->img_n = (color & 2 ? 3 : 1) + (color & 4 ? 1 : 0); |
| if ((1 << 30) / s->img_x / s->img_n < s->img_y) return stbi__err("too large", "Image too large to decode"); |
| if (scan == STBI__SCAN_header) return 1; |
| } else { |
| // if paletted, then pal_n is our final components, and |
| // img_n is # components to decompress/filter. |
| s->img_n = 1; |
| if ((1 << 30) / s->img_x / 4 < s->img_y) return stbi__err("too large","Corrupt PNG"); |
| // if SCAN_header, have to scan to see if we have a tRNS |
| } |
| break; |
| } |
| |
| case STBI__PNG_TYPE('P','L','T','E'): { |
| if (first) return stbi__err("first not IHDR", "Corrupt PNG"); |
| if (c.length > 256*3) return stbi__err("invalid PLTE","Corrupt PNG"); |
| pal_len = c.length / 3; |
| if (pal_len * 3 != c.length) return stbi__err("invalid PLTE","Corrupt PNG"); |
| for (i=0; i < pal_len; ++i) { |
| palette[i*4+0] = stbi__get8(s); |
| palette[i*4+1] = stbi__get8(s); |
| palette[i*4+2] = stbi__get8(s); |
| palette[i*4+3] = 255; |
| } |
| break; |
| } |
| |
| case STBI__PNG_TYPE('t','R','N','S'): { |
| if (first) return stbi__err("first not IHDR", "Corrupt PNG"); |
| if (z->idata) return stbi__err("tRNS after IDAT","Corrupt PNG"); |
| if (pal_img_n) { |
| if (scan == STBI__SCAN_header) { s->img_n = 4; return 1; } |
| if (pal_len == 0) return stbi__err("tRNS before PLTE","Corrupt PNG"); |
| if (c.length > pal_len) return stbi__err("bad tRNS len","Corrupt PNG"); |
| pal_img_n = 4; |
| for (i=0; i < c.length; ++i) |
| palette[i*4+3] = stbi__get8(s); |
| } else { |
| if (!(s->img_n & 1)) return stbi__err("tRNS with alpha","Corrupt PNG"); |
| if (c.length != (stbi__uint32) s->img_n*2) return stbi__err("bad tRNS len","Corrupt PNG"); |
| has_trans = 1; |
| if (z->depth == 16) { |
| for (k = 0; k < s->img_n; ++k) tc16[k] = (stbi__uint16)stbi__get16be(s); // copy the values as-is |
| } else { |
| for (k = 0; k < s->img_n; ++k) tc[k] = (stbi_uc)(stbi__get16be(s) & 255) * stbi__depth_scale_table[z->depth]; // non 8-bit images will be larger |
| } |
| } |
| break; |
| } |
| |
| case STBI__PNG_TYPE('I','D','A','T'): { |
| if (first) return stbi__err("first not IHDR", "Corrupt PNG"); |
| if (pal_img_n && !pal_len) return stbi__err("no PLTE","Corrupt PNG"); |
| if (scan == STBI__SCAN_header) { s->img_n = pal_img_n; return 1; } |
| if ((int)(ioff + c.length) < (int)ioff) return 0; |
| if (ioff + c.length > idata_limit) { |
| stbi__uint32 idata_limit_old = idata_limit; |
| stbi_uc *p; |
| if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096; |
| while (ioff + c.length > idata_limit) |
| idata_limit *= 2; |
| STBI_NOTUSED(idata_limit_old); |
| p = (stbi_uc *) STBI_REALLOC_SIZED(z->idata, idata_limit_old, idata_limit); if (p == NULL) return stbi__err("outofmem", "Out of memory"); |
| z->idata = p; |
| } |
| if (!stbi__getn(s, z->idata+ioff,c.length)) return stbi__err("outofdata","Corrupt PNG"); |
| ioff += c.length; |
| break; |
| } |
| |
| case STBI__PNG_TYPE('I','E','N','D'): { |
| stbi__uint32 raw_len, bpl; |
| if (first) return stbi__err("first not IHDR", "Corrupt PNG"); |
| if (scan != STBI__SCAN_load) return 1; |
| if (z->idata == NULL) return stbi__err("no IDAT","Corrupt PNG"); |
| // initial guess for decoded data size to avoid unnecessary reallocs |
| bpl = (s->img_x * z->depth + 7) / 8; // bytes per line, per component |
| raw_len = bpl * s->img_y * s->img_n /* pixels */ + s->img_y /* filter mode per row */; |
| z->expanded = (stbi_uc *) stbi_zlib_decode_malloc_guesssize_headerflag((char *) z->idata, ioff, raw_len, (int *) &raw_len, !is_iphone); |
| if (z->expanded == NULL) return 0; // zlib should set error |
| STBI_FREE(z->idata); z->idata = NULL; |
| if ((req_comp == s->img_n+1 && req_comp != 3 && !pal_img_n) || has_trans) |
| s->img_out_n = s->img_n+1; |
| else |
| s->img_out_n = s->img_n; |
| if (!stbi__create_png_image(z, z->expanded, raw_len, s->img_out_n, z->depth, color, interlace)) return 0; |
| if (has_trans) { |
| if (z->depth == 16) { |
| if (!stbi__compute_transparency16(z, tc16, s->img_out_n)) return 0; |
| } else { |
| if (!stbi__compute_transparency(z, tc, s->img_out_n)) return 0; |
| } |
| } |
| if (is_iphone && stbi__de_iphone_flag && s->img_out_n > 2) |
| stbi__de_iphone(z); |
| if (pal_img_n) { |
| // pal_img_n == 3 or 4 |
| s->img_n = pal_img_n; // record the actual colors we had |
| s->img_out_n = pal_img_n; |
| if (req_comp >= 3) s->img_out_n = req_comp; |
| if (!stbi__expand_png_palette(z, palette, pal_len, s->img_out_n)) |
| return 0; |
| } else if (has_trans) { |
| // non-paletted image with tRNS -> source image has (constant) alpha |
| ++s->img_n; |
| } |
| STBI_FREE(z->expanded); z->expanded = NULL; |
| return 1; |
| } |
| |
| default: |
| // if critical, fail |
| if (first) return stbi__err("first not IHDR", "Corrupt PNG"); |
| if ((c.type & (1 << 29)) == 0) { |
| #ifndef STBI_NO_FAILURE_STRINGS |
| // not threadsafe |
| static char invalid_chunk[] = "XXXX PNG chunk not known"; |
| invalid_chunk[0] = STBI__BYTECAST(c.type >> 24); |
| invalid_chunk[1] = STBI__BYTECAST(c.type >> 16); |
| invalid_chunk[2] = STBI__BYTECAST(c.type >> 8); |
| invalid_chunk[3] = STBI__BYTECAST(c.type >> 0); |
| #endif |
| return stbi__err(invalid_chunk, "PNG not supported: unknown PNG chunk type"); |
| } |
| stbi__skip(s, c.length); |
| break; |
| } |
| // end of PNG chunk, read and skip CRC |
| stbi__get32be(s); |
| } |
| } |
| |
| static void *stbi__do_png(stbi__png *p, int *x, int *y, int *n, int req_comp, stbi__result_info *ri) |
| { |
| void *result=NULL; |
| if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error"); |
| if (stbi__parse_png_file(p, STBI__SCAN_load, req_comp)) { |
| if (p->depth < 8) |
| ri->bits_per_channel = 8; |
| else |
| ri->bits_per_channel = p->depth; |
| result = p->out; |
| p->out = NULL; |
| if (req_comp && req_comp != p->s->img_out_n) { |
| if (ri->bits_per_channel == 8) |
| result = stbi__convert_format((unsigned char *) result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y); |
| else |
| result = stbi__convert_format16((stbi__uint16 *) result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y); |
| p->s->img_out_n = req_comp; |
| if (result == NULL) return result; |
| } |
| *x = p->s->img_x; |
| *y = p->s->img_y; |
| if (n) *n = p->s->img_n; |
| } |
| STBI_FREE(p->out); p->out = NULL; |
| STBI_FREE(p->expanded); p->expanded = NULL; |
| STBI_FREE(p->idata); p->idata = NULL; |
| |
| return result; |
| } |
| |
| static void *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri) |
| { |
| stbi__png p; |
| p.s = s; |
| return stbi__do_png(&p, x,y,comp,req_comp, ri); |
| } |
| |
| static int stbi__png_test(stbi__context *s) |
| { |
| int r; |
| r = stbi__check_png_header(s); |
| stbi__rewind(s); |
| return r; |
| } |
| |
| static int stbi__png_info_raw(stbi__png *p, int *x, int *y, int *comp) |
| { |
| if (!stbi__parse_png_file(p, STBI__SCAN_header, 0)) { |
| stbi__rewind( p->s ); |
| return 0; |
| } |
| if (x) *x = p->s->img_x; |
| if (y) *y = p->s->img_y; |
| if (comp) *comp = p->s->img_n; |
| return 1; |
| } |
| |
| static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| stbi__png p; |
| p.s = s; |
| return stbi__png_info_raw(&p, x, y, comp); |
| } |
| |
| static int stbi__png_is16(stbi__context *s) |
| { |
| stbi__png p; |
| p.s = s; |
| if (!stbi__png_info_raw(&p, NULL, NULL, NULL)) |
| return 0; |
| if (p.depth != 16) { |
| stbi__rewind(p.s); |
| return 0; |
| } |
| return 1; |
| } |
| #endif |
| |
| // Microsoft/Windows BMP image |
| |
| #ifndef STBI_NO_BMP |
| static int stbi__bmp_test_raw(stbi__context *s) |
| { |
| int r; |
| int sz; |
| if (stbi__get8(s) != 'B') return 0; |
| if (stbi__get8(s) != 'M') return 0; |
| stbi__get32le(s); // discard filesize |
| stbi__get16le(s); // discard reserved |
| stbi__get16le(s); // discard reserved |
| stbi__get32le(s); // discard data offset |
| sz = stbi__get32le(s); |
| r = (sz == 12 || sz == 40 || sz == 56 || sz == 108 || sz == 124); |
| return r; |
| } |
| |
| static int stbi__bmp_test(stbi__context *s) |
| { |
| int r = stbi__bmp_test_raw(s); |
| stbi__rewind(s); |
| return r; |
| } |
| |
| |
| // returns 0..31 for the highest set bit |
| static int stbi__high_bit(unsigned int z) |
| { |
| int n=0; |
| if (z == 0) return -1; |
| if (z >= 0x10000) { n += 16; z >>= 16; } |
| if (z >= 0x00100) { n += 8; z >>= 8; } |
| if (z >= 0x00010) { n += 4; z >>= 4; } |
| if (z >= 0x00004) { n += 2; z >>= 2; } |
| if (z >= 0x00002) { n += 1; z >>= 1; } |
| return n; |
| } |
| |
| static int stbi__bitcount(unsigned int a) |
| { |
| a = (a & 0x55555555) + ((a >> 1) & 0x55555555); // max 2 |
| a = (a & 0x33333333) + ((a >> 2) & 0x33333333); // max 4 |
| a = (a + (a >> 4)) & 0x0f0f0f0f; // max 8 per 4, now 8 bits |
| a = (a + (a >> 8)); // max 16 per 8 bits |
| a = (a + (a >> 16)); // max 32 per 8 bits |
| return a & 0xff; |
| } |
| |
| // extract an arbitrarily-aligned N-bit value (N=bits) |
| // from v, and then make it 8-bits long and fractionally |
| // extend it to full full range. |
| static int stbi__shiftsigned(unsigned int v, int shift, int bits) |
| { |
| static unsigned int mul_table[9] = { |
| 0, |
| 0xff/*0b11111111*/, 0x55/*0b01010101*/, 0x49/*0b01001001*/, 0x11/*0b00010001*/, |
| 0x21/*0b00100001*/, 0x41/*0b01000001*/, 0x81/*0b10000001*/, 0x01/*0b00000001*/, |
| }; |
| static unsigned int shift_table[9] = { |
| 0, 0,0,1,0,2,4,6,0, |
| }; |
| if (shift < 0) |
| v <<= -shift; |
| else |
| v >>= shift; |
| STBI_ASSERT(v >= 0 && v < 256); |
| v >>= (8-bits); |
| STBI_ASSERT(bits >= 0 && bits <= 8); |
| return (int) ((unsigned) v * mul_table[bits]) >> shift_table[bits]; |
| } |
| |
| typedef struct |
| { |
| int bpp, offset, hsz; |
| unsigned int mr,mg,mb,ma, all_a; |
| } stbi__bmp_data; |
| |
| static void *stbi__bmp_parse_header(stbi__context *s, stbi__bmp_data *info) |
| { |
| int hsz; |
| if (stbi__get8(s) != 'B' || stbi__get8(s) != 'M') return stbi__errpuc("not BMP", "Corrupt BMP"); |
| stbi__get32le(s); // discard filesize |
| stbi__get16le(s); // discard reserved |
| stbi__get16le(s); // discard reserved |
| info->offset = stbi__get32le(s); |
| info->hsz = hsz = stbi__get32le(s); |
| info->mr = info->mg = info->mb = info->ma = 0; |
| |
| if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108 && hsz != 124) return stbi__errpuc("unknown BMP", "BMP type not supported: unknown"); |
| if (hsz == 12) { |
| s->img_x = stbi__get16le(s); |
| s->img_y = stbi__get16le(s); |
| } else { |
| s->img_x = stbi__get32le(s); |
| s->img_y = stbi__get32le(s); |
| } |
| if (stbi__get16le(s) != 1) return stbi__errpuc("bad BMP", "bad BMP"); |
| info->bpp = stbi__get16le(s); |
| if (hsz != 12) { |
| int compress = stbi__get32le(s); |
| if (compress == 1 || compress == 2) return stbi__errpuc("BMP RLE", "BMP type not supported: RLE"); |
| stbi__get32le(s); // discard sizeof |
| stbi__get32le(s); // discard hres |
| stbi__get32le(s); // discard vres |
| stbi__get32le(s); // discard colorsused |
| stbi__get32le(s); // discard max important |
| if (hsz == 40 || hsz == 56) { |
| if (hsz == 56) { |
| stbi__get32le(s); |
| stbi__get32le(s); |
| stbi__get32le(s); |
| stbi__get32le(s); |
| } |
| if (info->bpp == 16 || info->bpp == 32) { |
| if (compress == 0) { |
| if (info->bpp == 32) { |
| info->mr = 0xffu << 16; |
| info->mg = 0xffu << 8; |
| info->mb = 0xffu << 0; |
| info->ma = 0xffu << 24; |
| info->all_a = 0; // if all_a is 0 at end, then we loaded alpha channel but it was all 0 |
| } else { |
| info->mr = 31u << 10; |
| info->mg = 31u << 5; |
| info->mb = 31u << 0; |
| } |
| } else if (compress == 3) { |
| info->mr = stbi__get32le(s); |
| info->mg = stbi__get32le(s); |
| info->mb = stbi__get32le(s); |
| // not documented, but generated by photoshop and handled by mspaint |
| if (info->mr == info->mg && info->mg == info->mb) { |
| // ?!?!? |
| return stbi__errpuc("bad BMP", "bad BMP"); |
| } |
| } else |
| return stbi__errpuc("bad BMP", "bad BMP"); |
| } |
| } else { |
| int i; |
| if (hsz != 108 && hsz != 124) |
| return stbi__errpuc("bad BMP", "bad BMP"); |
| info->mr = stbi__get32le(s); |
| info->mg = stbi__get32le(s); |
| info->mb = stbi__get32le(s); |
| info->ma = stbi__get32le(s); |
| stbi__get32le(s); // discard color space |
| for (i=0; i < 12; ++i) |
| stbi__get32le(s); // discard color space parameters |
| if (hsz == 124) { |
| stbi__get32le(s); // discard rendering intent |
| stbi__get32le(s); // discard offset of profile data |
| stbi__get32le(s); // discard size of profile data |
| stbi__get32le(s); // discard reserved |
| } |
| } |
| } |
| return (void *) 1; |
| } |
| |
| |
| static void *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri) |
| { |
| stbi_uc *out; |
| unsigned int mr=0,mg=0,mb=0,ma=0, all_a; |
| stbi_uc pal[256][4]; |
| int psize=0,i,j,width; |
| int flip_vertically, pad, target; |
| stbi__bmp_data info; |
| STBI_NOTUSED(ri); |
| |
| info.all_a = 255; |
| if (stbi__bmp_parse_header(s, &info) == NULL) |
| return NULL; // error code already set |
| |
| flip_vertically = ((int) s->img_y) > 0; |
| s->img_y = abs((int) s->img_y); |
| |
| mr = info.mr; |
| mg = info.mg; |
| mb = info.mb; |
| ma = info.ma; |
| all_a = info.all_a; |
| |
| if (info.hsz == 12) { |
| if (info.bpp < 24) |
| psize = (info.offset - 14 - 24) / 3; |
| } else { |
| if (info.bpp < 16) |
| psize = (info.offset - 14 - info.hsz) >> 2; |
| } |
| |
| s->img_n = ma ? 4 : 3; |
| if (req_comp && req_comp >= 3) // we can directly decode 3 or 4 |
| target = req_comp; |
| else |
| target = s->img_n; // if they want monochrome, we'll post-convert |
| |
| // sanity-check size |
| if (!stbi__mad3sizes_valid(target, s->img_x, s->img_y, 0)) |
| return stbi__errpuc("too large", "Corrupt BMP"); |
| |
| out = (stbi_uc *) stbi__malloc_mad3(target, s->img_x, s->img_y, 0); |
| if (!out) return stbi__errpuc("outofmem", "Out of memory"); |
| if (info.bpp < 16) { |
| int z=0; |
| if (psize == 0 || psize > 256) { STBI_FREE(out); return stbi__errpuc("invalid", "Corrupt BMP"); } |
| for (i=0; i < psize; ++i) { |
| pal[i][2] = stbi__get8(s); |
| pal[i][1] = stbi__get8(s); |
| pal[i][0] = stbi__get8(s); |
| if (info.hsz != 12) stbi__get8(s); |
| pal[i][3] = 255; |
| } |
| stbi__skip(s, info.offset - 14 - info.hsz - psize * (info.hsz == 12 ? 3 : 4)); |
| if (info.bpp == 1) width = (s->img_x + 7) >> 3; |
| else if (info.bpp == 4) width = (s->img_x + 1) >> 1; |
| else if (info.bpp == 8) width = s->img_x; |
| else { STBI_FREE(out); return stbi__errpuc("bad bpp", "Corrupt BMP"); } |
| pad = (-width)&3; |
| if (info.bpp == 1) { |
| for (j=0; j < (int) s->img_y; ++j) { |
| int bit_offset = 7, v = stbi__get8(s); |
| for (i=0; i < (int) s->img_x; ++i) { |
| int color = (v>>bit_offset)&0x1; |
| out[z++] = pal[color][0]; |
| out[z++] = pal[color][1]; |
| out[z++] = pal[color][2]; |
| if (target == 4) out[z++] = 255; |
| if (i+1 == (int) s->img_x) break; |
| if((--bit_offset) < 0) { |
| bit_offset = 7; |
| v = stbi__get8(s); |
| } |
| } |
| stbi__skip(s, pad); |
| } |
| } else { |
| for (j=0; j < (int) s->img_y; ++j) { |
| for (i=0; i < (int) s->img_x; i += 2) { |
| int v=stbi__get8(s),v2=0; |
| if (info.bpp == 4) { |
| v2 = v & 15; |
| v >>= 4; |
| } |
| out[z++] = pal[v][0]; |
| out[z++] = pal[v][1]; |
| out[z++] = pal[v][2]; |
| if (target == 4) out[z++] = 255; |
| if (i+1 == (int) s->img_x) break; |
| v = (info.bpp == 8) ? stbi__get8(s) : v2; |
| out[z++] = pal[v][0]; |
| out[z++] = pal[v][1]; |
| out[z++] = pal[v][2]; |
| if (target == 4) out[z++] = 255; |
| } |
| stbi__skip(s, pad); |
| } |
| } |
| } else { |
| int rshift=0,gshift=0,bshift=0,ashift=0,rcount=0,gcount=0,bcount=0,acount=0; |
| int z = 0; |
| int easy=0; |
| stbi__skip(s, info.offset - 14 - info.hsz); |
| if (info.bpp == 24) width = 3 * s->img_x; |
| else if (info.bpp == 16) width = 2*s->img_x; |
| else /* bpp = 32 and pad = 0 */ width=0; |
| pad = (-width) & 3; |
| if (info.bpp == 24) { |
| easy = 1; |
| } else if (info.bpp == 32) { |
| if (mb == 0xff && mg == 0xff00 && mr == 0x00ff0000 && ma == 0xff000000) |
| easy = 2; |
| } |
| if (!easy) { |
| if (!mr || !mg || !mb) { STBI_FREE(out); return stbi__errpuc("bad masks", "Corrupt BMP"); } |
| // right shift amt to put high bit in position #7 |
| rshift = stbi__high_bit(mr)-7; rcount = stbi__bitcount(mr); |
| gshift = stbi__high_bit(mg)-7; gcount = stbi__bitcount(mg); |
| bshift = stbi__high_bit(mb)-7; bcount = stbi__bitcount(mb); |
| ashift = stbi__high_bit(ma)-7; acount = stbi__bitcount(ma); |
| } |
| for (j=0; j < (int) s->img_y; ++j) { |
| if (easy) { |
| for (i=0; i < (int) s->img_x; ++i) { |
| unsigned char a; |
| out[z+2] = stbi__get8(s); |
| out[z+1] = stbi__get8(s); |
| out[z+0] = stbi__get8(s); |
| z += 3; |
| a = (easy == 2 ? stbi__get8(s) : 255); |
| all_a |= a; |
| if (target == 4) out[z++] = a; |
| } |
| } else { |
| int bpp = info.bpp; |
| for (i=0; i < (int) s->img_x; ++i) { |
| stbi__uint32 v = (bpp == 16 ? (stbi__uint32) stbi__get16le(s) : stbi__get32le(s)); |
| unsigned int a; |
| out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mr, rshift, rcount)); |
| out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mg, gshift, gcount)); |
| out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mb, bshift, bcount)); |
| a = (ma ? stbi__shiftsigned(v & ma, ashift, acount) : 255); |
| all_a |= a; |
| if (target == 4) out[z++] = STBI__BYTECAST(a); |
| } |
| } |
| stbi__skip(s, pad); |
| } |
| } |
| |
| // if alpha channel is all 0s, replace with all 255s |
| if (target == 4 && all_a == 0) |
| for (i=4*s->img_x*s->img_y-1; i >= 0; i -= 4) |
| out[i] = 255; |
| |
| if (flip_vertically) { |
| stbi_uc t; |
| for (j=0; j < (int) s->img_y>>1; ++j) { |
| stbi_uc *p1 = out + j *s->img_x*target; |
| stbi_uc *p2 = out + (s->img_y-1-j)*s->img_x*target; |
| for (i=0; i < (int) s->img_x*target; ++i) { |
| t = p1[i]; p1[i] = p2[i]; p2[i] = t; |
| } |
| } |
| } |
| |
| if (req_comp && req_comp != target) { |
| out = stbi__convert_format(out, target, req_comp, s->img_x, s->img_y); |
| if (out == NULL) return out; // stbi__convert_format frees input on failure |
| } |
| |
| *x = s->img_x; |
| *y = s->img_y; |
| if (comp) *comp = s->img_n; |
| return out; |
| } |
| #endif |
| |
| // Targa Truevision - TGA |
| // by Jonathan Dummer |
| #ifndef STBI_NO_TGA |
| // returns STBI_rgb or whatever, 0 on error |
| static int stbi__tga_get_comp(int bits_per_pixel, int is_grey, int* is_rgb16) |
| { |
| // only RGB or RGBA (incl. 16bit) or grey allowed |
| if (is_rgb16) *is_rgb16 = 0; |
| switch(bits_per_pixel) { |
| case 8: return STBI_grey; |
| case 16: if(is_grey) return STBI_grey_alpha; |
| // fallthrough |
| case 15: if(is_rgb16) *is_rgb16 = 1; |
| return STBI_rgb; |
| case 24: // fallthrough |
| case 32: return bits_per_pixel/8; |
| default: return 0; |
| } |
| } |
| |
| static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| int tga_w, tga_h, tga_comp, tga_image_type, tga_bits_per_pixel, tga_colormap_bpp; |
| int sz, tga_colormap_type; |
| stbi__get8(s); // discard Offset |
| tga_colormap_type = stbi__get8(s); // colormap type |
| if( tga_colormap_type > 1 ) { |
| stbi__rewind(s); |
| return 0; // only RGB or indexed allowed |
| } |
| tga_image_type = stbi__get8(s); // image type |
| if ( tga_colormap_type == 1 ) { // colormapped (paletted) image |
| if (tga_image_type != 1 && tga_image_type != 9) { |
| stbi__rewind(s); |
| return 0; |
| } |
| stbi__skip(s,4); // skip index of first colormap entry and number of entries |
| sz = stbi__get8(s); // check bits per palette color entry |
| if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) { |
| stbi__rewind(s); |
| return 0; |
| } |
| stbi__skip(s,4); // skip image x and y origin |
| tga_colormap_bpp = sz; |
| } else { // "normal" image w/o colormap - only RGB or grey allowed, +/- RLE |
| if ( (tga_image_type != 2) && (tga_image_type != 3) && (tga_image_type != 10) && (tga_image_type != 11) ) { |
| stbi__rewind(s); |
| return 0; // only RGB or grey allowed, +/- RLE |
| } |
| stbi__skip(s,9); // skip colormap specification and image x/y origin |
| tga_colormap_bpp = 0; |
| } |
| tga_w = stbi__get16le(s); |
| if( tga_w < 1 ) { |
| stbi__rewind(s); |
| return 0; // test width |
| } |
| tga_h = stbi__get16le(s); |
| if( tga_h < 1 ) { |
| stbi__rewind(s); |
| return 0; // test height |
| } |
| tga_bits_per_pixel = stbi__get8(s); // bits per pixel |
| stbi__get8(s); // ignore alpha bits |
| if (tga_colormap_bpp != 0) { |
| if((tga_bits_per_pixel != 8) && (tga_bits_per_pixel != 16)) { |
| // when using a colormap, tga_bits_per_pixel is the size of the indexes |
| // I don't think anything but 8 or 16bit indexes makes sense |
| stbi__rewind(s); |
| return 0; |
| } |
| tga_comp = stbi__tga_get_comp(tga_colormap_bpp, 0, NULL); |
| } else { |
| tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3) || (tga_image_type == 11), NULL); |
| } |
| if(!tga_comp) { |
| stbi__rewind(s); |
| return 0; |
| } |
| if (x) *x = tga_w; |
| if (y) *y = tga_h; |
| if (comp) *comp = tga_comp; |
| return 1; // seems to have passed everything |
| } |
| |
| static int stbi__tga_test(stbi__context *s) |
| { |
| int res = 0; |
| int sz, tga_color_type; |
| stbi__get8(s); // discard Offset |
| tga_color_type = stbi__get8(s); // color type |
| if ( tga_color_type > 1 ) goto errorEnd; // only RGB or indexed allowed |
| sz = stbi__get8(s); // image type |
| if ( tga_color_type == 1 ) { // colormapped (paletted) image |
| if (sz != 1 && sz != 9) goto errorEnd; // colortype 1 demands image type 1 or 9 |
| stbi__skip(s,4); // skip index of first colormap entry and number of entries |
| sz = stbi__get8(s); // check bits per palette color entry |
| if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) goto errorEnd; |
| stbi__skip(s,4); // skip image x and y origin |
| } else { // "normal" image w/o colormap |
| if ( (sz != 2) && (sz != 3) && (sz != 10) && (sz != 11) ) goto errorEnd; // only RGB or grey allowed, +/- RLE |
| stbi__skip(s,9); // skip colormap specification and image x/y origin |
| } |
| if ( stbi__get16le(s) < 1 ) goto errorEnd; // test width |
| if ( stbi__get16le(s) < 1 ) goto errorEnd; // test height |
| sz = stbi__get8(s); // bits per pixel |
| if ( (tga_color_type == 1) && (sz != 8) && (sz != 16) ) goto errorEnd; // for colormapped images, bpp is size of an index |
| if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) goto errorEnd; |
| |
| res = 1; // if we got this far, everything's good and we can return 1 instead of 0 |
| |
| errorEnd: |
| stbi__rewind(s); |
| return res; |
| } |
| |
| // read 16bit value and convert to 24bit RGB |
| static void stbi__tga_read_rgb16(stbi__context *s, stbi_uc* out) |
| { |
| stbi__uint16 px = (stbi__uint16)stbi__get16le(s); |
| stbi__uint16 fiveBitMask = 31; |
| // we have 3 channels with 5bits each |
| int r = (px >> 10) & fiveBitMask; |
| int g = (px >> 5) & fiveBitMask; |
| int b = px & fiveBitMask; |
| // Note that this saves the data in RGB(A) order, so it doesn't need to be swapped later |
| out[0] = (stbi_uc)((r * 255)/31); |
| out[1] = (stbi_uc)((g * 255)/31); |
| out[2] = (stbi_uc)((b * 255)/31); |
| |
| // some people claim that the most significant bit might be used for alpha |
| // (possibly if an alpha-bit is set in the "image descriptor byte") |
| // but that only made 16bit test images completely translucent.. |
| // so let's treat all 15 and 16bit TGAs as RGB with no alpha. |
| } |
| |
| static void *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri) |
| { |
| // read in the TGA header stuff |
| int tga_offset = stbi__get8(s); |
| int tga_indexed = stbi__get8(s); |
| int tga_image_type = stbi__get8(s); |
| int tga_is_RLE = 0; |
| int tga_palette_start = stbi__get16le(s); |
| int tga_palette_len = stbi__get16le(s); |
| int tga_palette_bits = stbi__get8(s); |
| int tga_x_origin = stbi__get16le(s); |
| int tga_y_origin = stbi__get16le(s); |
| int tga_width = stbi__get16le(s); |
| int tga_height = stbi__get16le(s); |
| int tga_bits_per_pixel = stbi__get8(s); |
| int tga_comp, tga_rgb16=0; |
| int tga_inverted = stbi__get8(s); |
| // int tga_alpha_bits = tga_inverted & 15; // the 4 lowest bits - unused (useless?) |
| // image data |
| unsigned char *tga_data; |
| unsigned char *tga_palette = NULL; |
| int i, j; |
| unsigned char raw_data[4] = {0}; |
| int RLE_count = 0; |
| int RLE_repeating = 0; |
| int read_next_pixel = 1; |
| STBI_NOTUSED(ri); |
| |
| // do a tiny bit of precessing |
| if ( tga_image_type >= 8 ) |
| { |
| tga_image_type -= 8; |
| tga_is_RLE = 1; |
| } |
| tga_inverted = 1 - ((tga_inverted >> 5) & 1); |
| |
| // If I'm paletted, then I'll use the number of bits from the palette |
| if ( tga_indexed ) tga_comp = stbi__tga_get_comp(tga_palette_bits, 0, &tga_rgb16); |
| else tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3), &tga_rgb16); |
| |
| if(!tga_comp) // shouldn't really happen, stbi__tga_test() should have ensured basic consistency |
| return stbi__errpuc("bad format", "Can't find out TGA pixelformat"); |
| |
| // tga info |
| *x = tga_width; |
| *y = tga_height; |
| if (comp) *comp = tga_comp; |
| |
| if (!stbi__mad3sizes_valid(tga_width, tga_height, tga_comp, 0)) |
| return stbi__errpuc("too large", "Corrupt TGA"); |
| |
| tga_data = (unsigned char*)stbi__malloc_mad3(tga_width, tga_height, tga_comp, 0); |
| if (!tga_data) return stbi__errpuc("outofmem", "Out of memory"); |
| |
| // skip to the data's starting position (offset usually = 0) |
| stbi__skip(s, tga_offset ); |
| |
| if ( !tga_indexed && !tga_is_RLE && !tga_rgb16 ) { |
| for (i=0; i < tga_height; ++i) { |
| int row = tga_inverted ? tga_height -i - 1 : i; |
| stbi_uc *tga_row = tga_data + row*tga_width*tga_comp; |
| stbi__getn(s, tga_row, tga_width * tga_comp); |
| } |
| } else { |
| // do I need to load a palette? |
| if ( tga_indexed) |
| { |
| // any data to skip? (offset usually = 0) |
| stbi__skip(s, tga_palette_start ); |
| // load the palette |
| tga_palette = (unsigned char*)stbi__malloc_mad2(tga_palette_len, tga_comp, 0); |
| if (!tga_palette) { |
| STBI_FREE(tga_data); |
| return stbi__errpuc("outofmem", "Out of memory"); |
| } |
| if (tga_rgb16) { |
| stbi_uc *pal_entry = tga_palette; |
| STBI_ASSERT(tga_comp == STBI_rgb); |
| for (i=0; i < tga_palette_len; ++i) { |
| stbi__tga_read_rgb16(s, pal_entry); |
| pal_entry += tga_comp; |
| } |
| } else if (!stbi__getn(s, tga_palette, tga_palette_len * tga_comp)) { |
| STBI_FREE(tga_data); |
| STBI_FREE(tga_palette); |
| return stbi__errpuc("bad palette", "Corrupt TGA"); |
| } |
| } |
| // load the data |
| for (i=0; i < tga_width * tga_height; ++i) |
| { |
| // if I'm in RLE mode, do I need to get a RLE stbi__pngchunk? |
| if ( tga_is_RLE ) |
| { |
| if ( RLE_count == 0 ) |
| { |
| // yep, get the next byte as a RLE command |
| int RLE_cmd = stbi__get8(s); |
| RLE_count = 1 + (RLE_cmd & 127); |
| RLE_repeating = RLE_cmd >> 7; |
| read_next_pixel = 1; |
| } else if ( !RLE_repeating ) |
| { |
| read_next_pixel = 1; |
| } |
| } else |
| { |
| read_next_pixel = 1; |
| } |
| // OK, if I need to read a pixel, do it now |
| if ( read_next_pixel ) |
| { |
| // load however much data we did have |
| if ( tga_indexed ) |
| { |
| // read in index, then perform the lookup |
| int pal_idx = (tga_bits_per_pixel == 8) ? stbi__get8(s) : stbi__get16le(s); |
| if ( pal_idx >= tga_palette_len ) { |
| // invalid index |
| pal_idx = 0; |
| } |
| pal_idx *= tga_comp; |
| for (j = 0; j < tga_comp; ++j) { |
| raw_data[j] = tga_palette[pal_idx+j]; |
| } |
| } else if(tga_rgb16) { |
| STBI_ASSERT(tga_comp == STBI_rgb); |
| stbi__tga_read_rgb16(s, raw_data); |
| } else { |
| // read in the data raw |
| for (j = 0; j < tga_comp; ++j) { |
| raw_data[j] = stbi__get8(s); |
| } |
| } |
| // clear the reading flag for the next pixel |
| read_next_pixel = 0; |
| } // end of reading a pixel |
| |
| // copy data |
| for (j = 0; j < tga_comp; ++j) |
| tga_data[i*tga_comp+j] = raw_data[j]; |
| |
| // in case we're in RLE mode, keep counting down |
| --RLE_count; |
| } |
| // do I need to invert the image? |
| if ( tga_inverted ) |
| { |
| for (j = 0; j*2 < tga_height; ++j) |
| { |
| int index1 = j * tga_width * tga_comp; |
| int index2 = (tga_height - 1 - j) * tga_width * tga_comp; |
| for (i = tga_width * tga_comp; i > 0; --i) |
| { |
| unsigned char temp = tga_data[index1]; |
| tga_data[index1] = tga_data[index2]; |
| tga_data[index2] = temp; |
| ++index1; |
| ++index2; |
| } |
| } |
| } |
| // clear my palette, if I had one |
| if ( tga_palette != NULL ) |
| { |
| STBI_FREE( tga_palette ); |
| } |
| } |
| |
| // swap RGB - if the source data was RGB16, it already is in the right order |
| if (tga_comp >= 3 && !tga_rgb16) |
| { |
| unsigned char* tga_pixel = tga_data; |
| for (i=0; i < tga_width * tga_height; ++i) |
| { |
| unsigned char temp = tga_pixel[0]; |
| tga_pixel[0] = tga_pixel[2]; |
| tga_pixel[2] = temp; |
| tga_pixel += tga_comp; |
| } |
| } |
| |
| // convert to target component count |
| if (req_comp && req_comp != tga_comp) |
| tga_data = stbi__convert_format(tga_data, tga_comp, req_comp, tga_width, tga_height); |
| |
| // the things I do to get rid of an error message, and yet keep |
| // Microsoft's C compilers happy... [8^( |
| tga_palette_start = tga_palette_len = tga_palette_bits = |
| tga_x_origin = tga_y_origin = 0; |
| // OK, done |
| return tga_data; |
| } |
| #endif |
| |
| // ************************************************************************************************* |
| // Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicolas Schulz, tweaked by STB |
| |
| #ifndef STBI_NO_PSD |
| static int stbi__psd_test(stbi__context *s) |
| { |
| int r = (stbi__get32be(s) == 0x38425053); |
| stbi__rewind(s); |
| return r; |
| } |
| |
| static int stbi__psd_decode_rle(stbi__context *s, stbi_uc *p, int pixelCount) |
| { |
| int count, nleft, len; |
| |
| count = 0; |
| while ((nleft = pixelCount - count) > 0) { |
| len = stbi__get8(s); |
| if (len == 128) { |
| // No-op. |
| } else if (len < 128) { |
| // Copy next len+1 bytes literally. |
| len++; |
| if (len > nleft) return 0; // corrupt data |
| count += len; |
| while (len) { |
| *p = stbi__get8(s); |
| p += 4; |
| len--; |
| } |
| } else if (len > 128) { |
| stbi_uc val; |
| // Next -len+1 bytes in the dest are replicated from next source byte. |
| // (Interpret len as a negative 8-bit int.) |
| len = 257 - len; |
| if (len > nleft) return 0; // corrupt data |
| val = stbi__get8(s); |
| count += len; |
| while (len) { |
| *p = val; |
| p += 4; |
| len--; |
| } |
| } |
| } |
| |
| return 1; |
| } |
| |
| static void *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc) |
| { |
| int pixelCount; |
| int channelCount, compression; |
| int channel, i; |
| int bitdepth; |
| int w,h; |
| stbi_uc *out; |
| STBI_NOTUSED(ri); |
| |
| // Check identifier |
| if (stbi__get32be(s) != 0x38425053) // "8BPS" |
| return stbi__errpuc("not PSD", "Corrupt PSD image"); |
| |
| // Check file type version. |
| if (stbi__get16be(s) != 1) |
| return stbi__errpuc("wrong version", "Unsupported version of PSD image"); |
| |
| // Skip 6 reserved bytes. |
| stbi__skip(s, 6 ); |
| |
| // Read the number of channels (R, G, B, A, etc). |
| channelCount = stbi__get16be(s); |
| if (channelCount < 0 || channelCount > 16) |
| return stbi__errpuc("wrong channel count", "Unsupported number of channels in PSD image"); |
| |
| // Read the rows and columns of the image. |
| h = stbi__get32be(s); |
| w = stbi__get32be(s); |
| |
| // Make sure the depth is 8 bits. |
| bitdepth = stbi__get16be(s); |
| if (bitdepth != 8 && bitdepth != 16) |
| return stbi__errpuc("unsupported bit depth", "PSD bit depth is not 8 or 16 bit"); |
| |
| // Make sure the color mode is RGB. |
| // Valid options are: |
| // 0: Bitmap |
| // 1: Grayscale |
| // 2: Indexed color |
| // 3: RGB color |
| // 4: CMYK color |
| // 7: Multichannel |
| // 8: Duotone |
| // 9: Lab color |
| if (stbi__get16be(s) != 3) |
| return stbi__errpuc("wrong color format", "PSD is not in RGB color format"); |
| |
| // Skip the Mode Data. (It's the palette for indexed color; other info for other modes.) |
| stbi__skip(s,stbi__get32be(s) ); |
| |
| // Skip the image resources. (resolution, pen tool paths, etc) |
| stbi__skip(s, stbi__get32be(s) ); |
| |
| // Skip the reserved data. |
| stbi__skip(s, stbi__get32be(s) ); |
| |
| // Find out if the data is compressed. |
| // Known values: |
| // 0: no compression |
| // 1: RLE compressed |
| compression = stbi__get16be(s); |
| if (compression > 1) |
| return stbi__errpuc("bad compression", "PSD has an unknown compression format"); |
| |
| // Check size |
| if (!stbi__mad3sizes_valid(4, w, h, 0)) |
| return stbi__errpuc("too large", "Corrupt PSD"); |
| |
| // Create the destination image. |
| |
| if (!compression && bitdepth == 16 && bpc == 16) { |
| out = (stbi_uc *) stbi__malloc_mad3(8, w, h, 0); |
| ri->bits_per_channel = 16; |
| } else |
| out = (stbi_uc *) stbi__malloc(4 * w*h); |
| |
| if (!out) return stbi__errpuc("outofmem", "Out of memory"); |
| pixelCount = w*h; |
| |
| // Initialize the data to zero. |
| //memset( out, 0, pixelCount * 4 ); |
| |
| // Finally, the image data. |
| if (compression) { |
| // RLE as used by .PSD and .TIFF |
| // Loop until you get the number of unpacked bytes you are expecting: |
| // Read the next source byte into n. |
| // If n is between 0 and 127 inclusive, copy the next n+1 bytes literally. |
| // Else if n is between -127 and -1 inclusive, copy the next byte -n+1 times. |
| // Else if n is 128, noop. |
| // Endloop |
| |
| // The RLE-compressed data is preceded by a 2-byte data count for each row in the data, |
| // which we're going to just skip. |
| stbi__skip(s, h * channelCount * 2 ); |
| |
| // Read the RLE data by channel. |
| for (channel = 0; channel < 4; channel++) { |
| stbi_uc *p; |
| |
| p = out+channel; |
| if (channel >= channelCount) { |
| // Fill this channel with default data. |
| for (i = 0; i < pixelCount; i++, p += 4) |
| *p = (channel == 3 ? 255 : 0); |
| } else { |
| // Read the RLE data. |
| if (!stbi__psd_decode_rle(s, p, pixelCount)) { |
| STBI_FREE(out); |
| return stbi__errpuc("corrupt", "bad RLE data"); |
| } |
| } |
| } |
| |
| } else { |
| // We're at the raw image data. It's each channel in order (Red, Green, Blue, Alpha, ...) |
| // where each channel consists of an 8-bit (or 16-bit) value for each pixel in the image. |
| |
| // Read the data by channel. |
| for (channel = 0; channel < 4; channel++) { |
| if (channel >= channelCount) { |
| // Fill this channel with default data. |
| if (bitdepth == 16 && bpc == 16) { |
| stbi__uint16 *q = ((stbi__uint16 *) out) + channel; |
| stbi__uint16 val = channel == 3 ? 65535 : 0; |
| for (i = 0; i < pixelCount; i++, q += 4) |
| *q = val; |
| } else { |
| stbi_uc *p = out+channel; |
| stbi_uc val = channel == 3 ? 255 : 0; |
| for (i = 0; i < pixelCount; i++, p += 4) |
| *p = val; |
| } |
| } else { |
| if (ri->bits_per_channel == 16) { // output bpc |
| stbi__uint16 *q = ((stbi__uint16 *) out) + channel; |
| for (i = 0; i < pixelCount; i++, q += 4) |
| *q = (stbi__uint16) stbi__get16be(s); |
| } else { |
| stbi_uc *p = out+channel; |
| if (bitdepth == 16) { // input bpc |
| for (i = 0; i < pixelCount; i++, p += 4) |
| *p = (stbi_uc) (stbi__get16be(s) >> 8); |
| } else { |
| for (i = 0; i < pixelCount; i++, p += 4) |
| *p = stbi__get8(s); |
| } |
| } |
| } |
| } |
| } |
| |
| // remove weird white matte from PSD |
| if (channelCount >= 4) { |
| if (ri->bits_per_channel == 16) { |
| for (i=0; i < w*h; ++i) { |
| stbi__uint16 *pixel = (stbi__uint16 *) out + 4*i; |
| if (pixel[3] != 0 && pixel[3] != 65535) { |
| float a = pixel[3] / 65535.0f; |
| float ra = 1.0f / a; |
| float inv_a = 65535.0f * (1 - ra); |
| pixel[0] = (stbi__uint16) (pixel[0]*ra + inv_a); |
| pixel[1] = (stbi__uint16) (pixel[1]*ra + inv_a); |
| pixel[2] = (stbi__uint16) (pixel[2]*ra + inv_a); |
| } |
| } |
| } else { |
| for (i=0; i < w*h; ++i) { |
| unsigned char *pixel = out + 4*i; |
| if (pixel[3] != 0 && pixel[3] != 255) { |
| float a = pixel[3] / 255.0f; |
| float ra = 1.0f / a; |
| float inv_a = 255.0f * (1 - ra); |
| pixel[0] = (unsigned char) (pixel[0]*ra + inv_a); |
| pixel[1] = (unsigned char) (pixel[1]*ra + inv_a); |
| pixel[2] = (unsigned char) (pixel[2]*ra + inv_a); |
| } |
| } |
| } |
| } |
| |
| // convert to desired output format |
| if (req_comp && req_comp != 4) { |
| if (ri->bits_per_channel == 16) |
| out = (stbi_uc *) stbi__convert_format16((stbi__uint16 *) out, 4, req_comp, w, h); |
| else |
| out = stbi__convert_format(out, 4, req_comp, w, h); |
| if (out == NULL) return out; // stbi__convert_format frees input on failure |
| } |
| |
| if (comp) *comp = 4; |
| *y = h; |
| *x = w; |
| |
| return out; |
| } |
| #endif |
| |
| // ************************************************************************************************* |
| // Softimage PIC loader |
| // by Tom Seddon |
| // |
| // See http://softimage.wiki.softimage.com/index.php/INFO:_PIC_file_format |
| // See http://ozviz.wasp.uwa.edu.au/~pbourke/dataformats/softimagepic/ |
| |
| #ifndef STBI_NO_PIC |
| static int stbi__pic_is4(stbi__context *s,const char *str) |
| { |
| int i; |
| for (i=0; i<4; ++i) |
| if (stbi__get8(s) != (stbi_uc)str[i]) |
| return 0; |
| |
| return 1; |
| } |
| |
| static int stbi__pic_test_core(stbi__context *s) |
| { |
| int i; |
| |
| if (!stbi__pic_is4(s,"\x53\x80\xF6\x34")) |
| return 0; |
| |
| for(i=0;i<84;++i) |
| stbi__get8(s); |
| |
| if (!stbi__pic_is4(s,"PICT")) |
| return 0; |
| |
| return 1; |
| } |
| |
| typedef struct |
| { |
| stbi_uc size,type,channel; |
| } stbi__pic_packet; |
| |
| static stbi_uc *stbi__readval(stbi__context *s, int channel, stbi_uc *dest) |
| { |
| int mask=0x80, i; |
| |
| for (i=0; i<4; ++i, mask>>=1) { |
| if (channel & mask) { |
| if (stbi__at_eof(s)) return stbi__errpuc("bad file","PIC file too short"); |
| dest[i]=stbi__get8(s); |
| } |
| } |
| |
| return dest; |
| } |
| |
| static void stbi__copyval(int channel,stbi_uc *dest,const stbi_uc *src) |
| { |
| int mask=0x80,i; |
| |
| for (i=0;i<4; ++i, mask>>=1) |
| if (channel&mask) |
| dest[i]=src[i]; |
| } |
| |
| static stbi_uc *stbi__pic_load_core(stbi__context *s,int width,int height,int *comp, stbi_uc *result) |
| { |
| int act_comp=0,num_packets=0,y,chained; |
| stbi__pic_packet packets[10]; |
| |
| // this will (should...) cater for even some bizarre stuff like having data |
| // for the same channel in multiple packets. |
| do { |
| stbi__pic_packet *packet; |
| |
| if (num_packets==sizeof(packets)/sizeof(packets[0])) |
| return stbi__errpuc("bad format","too many packets"); |
| |
| packet = &packets[num_packets++]; |
| |
| chained = stbi__get8(s); |
| packet->size = stbi__get8(s); |
| packet->type = stbi__get8(s); |
| packet->channel = stbi__get8(s); |
| |
| act_comp |= packet->channel; |
| |
| if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (reading packets)"); |
| if (packet->size != 8) return stbi__errpuc("bad format","packet isn't 8bpp"); |
| } while (chained); |
| |
| *comp = (act_comp & 0x10 ? 4 : 3); // has alpha channel? |
| |
| for(y=0; y<height; ++y) { |
| int packet_idx; |
| |
| for(packet_idx=0; packet_idx < num_packets; ++packet_idx) { |
| stbi__pic_packet *packet = &packets[packet_idx]; |
| stbi_uc *dest = result+y*width*4; |
| |
| switch (packet->type) { |
| default: |
| return stbi__errpuc("bad format","packet has bad compression type"); |
| |
| case 0: {//uncompressed |
| int x; |
| |
| for(x=0;x<width;++x, dest+=4) |
| if (!stbi__readval(s,packet->channel,dest)) |
| return 0; |
| break; |
| } |
| |
| case 1://Pure RLE |
| { |
| int left=width, i; |
| |
| while (left>0) { |
| stbi_uc count,value[4]; |
| |
| count=stbi__get8(s); |
| if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (pure read count)"); |
| |
| if (count > left) |
| count = (stbi_uc) left; |
| |
| if (!stbi__readval(s,packet->channel,value)) return 0; |
| |
| for(i=0; i<count; ++i,dest+=4) |
| stbi__copyval(packet->channel,dest,value); |
| left -= count; |
| } |
| } |
| break; |
| |
| case 2: {//Mixed RLE |
| int left=width; |
| while (left>0) { |
| int count = stbi__get8(s), i; |
| if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (mixed read count)"); |
| |
| if (count >= 128) { // Repeated |
| stbi_uc value[4]; |
| |
| if (count==128) |
| count = stbi__get16be(s); |
| else |
| count -= 127; |
| if (count > left) |
| return stbi__errpuc("bad file","scanline overrun"); |
| |
| if (!stbi__readval(s,packet->channel,value)) |
| return 0; |
| |
| for(i=0;i<count;++i, dest += 4) |
| stbi__copyval(packet->channel,dest,value); |
| } else { // Raw |
| ++count; |
| if (count>left) return stbi__errpuc("bad file","scanline overrun"); |
| |
| for(i=0;i<count;++i, dest+=4) |
| if (!stbi__readval(s,packet->channel,dest)) |
| return 0; |
| } |
| left-=count; |
| } |
| break; |
| } |
| } |
| } |
| } |
| |
| return result; |
| } |
| |
| static void *stbi__pic_load(stbi__context *s,int *px,int *py,int *comp,int req_comp, stbi__result_info *ri) |
| { |
| stbi_uc *result; |
| int i, x,y, internal_comp; |
| STBI_NOTUSED(ri); |
| |
| if (!comp) comp = &internal_comp; |
| |
| for (i=0; i<92; ++i) |
| stbi__get8(s); |
| |
| x = stbi__get16be(s); |
| y = stbi__get16be(s); |
| if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (pic header)"); |
| if (!stbi__mad3sizes_valid(x, y, 4, 0)) return stbi__errpuc("too large", "PIC image too large to decode"); |
| |
| stbi__get32be(s); //skip `ratio' |
| stbi__get16be(s); //skip `fields' |
| stbi__get16be(s); //skip `pad' |
| |
| // intermediate buffer is RGBA |
| result = (stbi_uc *) stbi__malloc_mad3(x, y, 4, 0); |
| memset(result, 0xff, x*y*4); |
| |
| if (!stbi__pic_load_core(s,x,y,comp, result)) { |
| STBI_FREE(result); |
| result=0; |
| } |
| *px = x; |
| *py = y; |
| if (req_comp == 0) req_comp = *comp; |
| result=stbi__convert_format(result,4,req_comp,x,y); |
| |
| return result; |
| } |
| |
| static int stbi__pic_test(stbi__context *s) |
| { |
| int r = stbi__pic_test_core(s); |
| stbi__rewind(s); |
| return r; |
| } |
| #endif |
| |
| // ************************************************************************************************* |
| // GIF loader -- public domain by Jean-Marc Lienher -- simplified/shrunk by stb |
| |
| #ifndef STBI_NO_GIF |
| typedef struct |
| { |
| stbi__int16 prefix; |
| stbi_uc first; |
| stbi_uc suffix; |
| } stbi__gif_lzw; |
| |
| typedef struct |
| { |
| int w,h; |
| stbi_uc *out; // output buffer (always 4 components) |
| stbi_uc *background; // The current "background" as far as a gif is concerned |
| stbi_uc *history; |
| int flags, bgindex, ratio, transparent, eflags; |
| stbi_uc pal[256][4]; |
| stbi_uc lpal[256][4]; |
| stbi__gif_lzw codes[8192]; |
| stbi_uc *color_table; |
| int parse, step; |
| int lflags; |
| int start_x, start_y; |
| int max_x, max_y; |
| int cur_x, cur_y; |
| int line_size; |
| int delay; |
| } stbi__gif; |
| |
| static int stbi__gif_test_raw(stbi__context *s) |
| { |
| int sz; |
| if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8') return 0; |
| sz = stbi__get8(s); |
| if (sz != '9' && sz != '7') return 0; |
| if (stbi__get8(s) != 'a') return 0; |
| return 1; |
| } |
| |
| static int stbi__gif_test(stbi__context *s) |
| { |
| int r = stbi__gif_test_raw(s); |
| stbi__rewind(s); |
| return r; |
| } |
| |
| static void stbi__gif_parse_colortable(stbi__context *s, stbi_uc pal[256][4], int num_entries, int transp) |
| { |
| int i; |
| for (i=0; i < num_entries; ++i) { |
| pal[i][2] = stbi__get8(s); |
| pal[i][1] = stbi__get8(s); |
| pal[i][0] = stbi__get8(s); |
| pal[i][3] = transp == i ? 0 : 255; |
| } |
| } |
| |
| static int stbi__gif_header(stbi__context *s, stbi__gif *g, int *comp, int is_info) |
| { |
| stbi_uc version; |
| if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8') |
| return stbi__err("not GIF", "Corrupt GIF"); |
| |
| version = stbi__get8(s); |
| if (version != '7' && version != '9') return stbi__err("not GIF", "Corrupt GIF"); |
| if (stbi__get8(s) != 'a') return stbi__err("not GIF", "Corrupt GIF"); |
| |
| stbi__g_failure_reason = ""; |
| g->w = stbi__get16le(s); |
| g->h = stbi__get16le(s); |
| g->flags = stbi__get8(s); |
| g->bgindex = stbi__get8(s); |
| g->ratio = stbi__get8(s); |
| g->transparent = -1; |
| |
| if (comp != 0) *comp = 4; // can't actually tell whether it's 3 or 4 until we parse the comments |
| |
| if (is_info) return 1; |
| |
| if (g->flags & 0x80) |
| stbi__gif_parse_colortable(s,g->pal, 2 << (g->flags & 7), -1); |
| |
| return 1; |
| } |
| |
| static int stbi__gif_info_raw(stbi__context *s, int *x, int *y, int *comp) |
| { |
| stbi__gif* g = (stbi__gif*) stbi__malloc(sizeof(stbi__gif)); |
| if (!stbi__gif_header(s, g, comp, 1)) { |
| STBI_FREE(g); |
| stbi__rewind( s ); |
| return 0; |
| } |
| if (x) *x = g->w; |
| if (y) *y = g->h; |
| STBI_FREE(g); |
| return 1; |
| } |
| |
| static void stbi__out_gif_code(stbi__gif *g, stbi__uint16 code) |
| { |
| stbi_uc *p, *c; |
| int idx; |
| |
| // recurse to decode the prefixes, since the linked-list is backwards, |
| // and working backwards through an interleaved image would be nasty |
| if (g->codes[code].prefix >= 0) |
| stbi__out_gif_code(g, g->codes[code].prefix); |
| |
| if (g->cur_y >= g->max_y) return; |
| |
| idx = g->cur_x + g->cur_y; |
| p = &g->out[idx]; |
| g->history[idx / 4] = 1; |
| |
| c = &g->color_table[g->codes[code].suffix * 4]; |
| if (c[3] > 128) { // don't render transparent pixels; |
| p[0] = c[2]; |
| p[1] = c[1]; |
| p[2] = c[0]; |
| p[3] = c[3]; |
| } |
| g->cur_x += 4; |
| |
| if (g->cur_x >= g->max_x) { |
| g->cur_x = g->start_x; |
| g->cur_y += g->step; |
| |
| while (g->cur_y >= g->max_y && g->parse > 0) { |
| g->step = (1 << g->parse) * g->line_size; |
| g->cur_y = g->start_y + (g->step >> 1); |
| --g->parse; |
| } |
| } |
| } |
| |
| static stbi_uc *stbi__process_gif_raster(stbi__context *s, stbi__gif *g) |
| { |
| stbi_uc lzw_cs; |
| stbi__int32 len, init_code; |
| stbi__uint32 first; |
| stbi__int32 codesize, codemask, avail, oldcode, bits, valid_bits, clear; |
| stbi__gif_lzw *p; |
| |
| lzw_cs = stbi__get8(s); |
| if (lzw_cs > 12) return NULL; |
| clear = 1 << lzw_cs; |
| first = 1; |
| codesize = lzw_cs + 1; |
| codemask = (1 << codesize) - 1; |
| bits = 0; |
| valid_bits = 0; |
| for (init_code = 0; init_code < clear; init_code++) { |
| g->codes[init_code].prefix = -1; |
| g->codes[init_code].first = (stbi_uc) init_code; |
| g->codes[init_code].suffix = (stbi_uc) init_code; |
| } |
| |
| // support no starting clear code |
| avail = clear+2; |
| oldcode = -1; |
| |
| len = 0; |
| for(;;) { |
| if (valid_bits < codesize) { |
| if (len == 0) { |
| len = stbi__get8(s); // start new block |
| if (len == 0) |
| return g->out; |
| } |
| --len; |
| bits |= (stbi__int32) stbi__get8(s) << valid_bits; |
| valid_bits += 8; |
| } else { |
| stbi__int32 code = bits & codemask; |
| bits >>= codesize; |
| valid_bits -= codesize; |
| // @OPTIMIZE: is there some way we can accelerate the non-clear path? |
| if (code == clear) { // clear code |
| codesize = lzw_cs + 1; |
| codemask = (1 << codesize) - 1; |
| avail = clear + 2; |
| oldcode = -1; |
| first = 0; |
| } else if (code == clear + 1) { // end of stream code |
| stbi__skip(s, len); |
| while ((len = stbi__get8(s)) > 0) |
| stbi__skip(s,len); |
| return g->out; |
| } else if (code <= avail) { |
| if (first) { |
| return stbi__errpuc("no clear code", "Corrupt GIF"); |
| } |
| |
| if (oldcode >= 0) { |
| p = &g->codes[avail++]; |
| if (avail > 8192) { |
| return stbi__errpuc("too many codes", "Corrupt GIF"); |
| } |
| |
| p->prefix = (stbi__int16) oldcode; |
| p->first = g->codes[oldcode].first; |
| p->suffix = (code == avail) ? p->first : g->codes[code].first; |
| } else if (code == avail) |
| return stbi__errpuc("illegal code in raster", "Corrupt GIF"); |
| |
| stbi__out_gif_code(g, (stbi__uint16) code); |
| |
| if ((avail & codemask) == 0 && avail <= 0x0FFF) { |
| codesize++; |
| codemask = (1 << codesize) - 1; |
| } |
| |
| oldcode = code; |
| } else { |
| return stbi__errpuc("illegal code in raster", "Corrupt GIF"); |
| } |
| } |
| } |
| } |
| |
| // this function is designed to support animated gifs, although stb_image doesn't support it |
| // two back is the image from two frames ago, used for a very specific disposal format |
| static stbi_uc *stbi__gif_load_next(stbi__context *s, stbi__gif *g, int *comp, int req_comp, stbi_uc *two_back) |
| { |
| int dispose; |
| int first_frame; |
| int pi; |
| int pcount; |
| STBI_NOTUSED(req_comp); |
| |
| // on first frame, any non-written pixels get the background colour (non-transparent) |
| first_frame = 0; |
| if (g->out == 0) { |
| if (!stbi__gif_header(s, g, comp,0)) return 0; // stbi__g_failure_reason set by stbi__gif_header |
| g->out = (stbi_uc *) stbi__malloc(4 * g->w * g->h); |
| g->background = (stbi_uc *) stbi__malloc(4 * g->w * g->h); |
| g->history = (stbi_uc *) stbi__malloc(g->w * g->h); |
| if (g->out == 0) return stbi__errpuc("outofmem", "Out of memory"); |
| |
| // image is treated as "transparent" at the start - ie, nothing overwrites the current background; |
| // background colour is only used for pixels that are not rendered first frame, after that "background" |
| // color refers to the color that was there the previous frame. |
| memset( g->out, 0x00, 4 * g->w * g->h ); |
| memset( g->background, 0x00, 4 * g->w * g->h ); // state of the background (starts transparent) |
| memset( g->history, 0x00, g->w * g->h ); // pixels that were affected previous frame |
| first_frame = 1; |
| } else { |
| // second frame - how do we dispoase of the previous one? |
| dispose = (g->eflags & 0x1C) >> 2; |
| pcount = g->w * g->h; |
| |
| if ((dispose == 3) && (two_back == 0)) { |
| dispose = 2; // if I don't have an image to revert back to, default to the old background |
| } |
| |
| if (dispose == 3) { // use previous graphic |
| for (pi = 0; pi < pcount; ++pi) { |
| if (g->history[pi]) { |
| memcpy( &g->out[pi * 4], &two_back[pi * 4], 4 ); |
| } |
| } |
| } else if (dispose == 2) { |
| // restore what was changed last frame to background before that frame; |
| for (pi = 0; pi < pcount; ++pi) { |
| if (g->history[pi]) { |
| memcpy( &g->out[pi * 4], &g->background[pi * 4], 4 ); |
| } |
| } |
| } else { |
| // This is a non-disposal case eithe way, so just |
| // leave the pixels as is, and they will become the new background |
| // 1: do not dispose |
| // 0: not specified. |
| } |
| |
| // background is what out is after the undoing of the previou frame; |
| memcpy( g->background, g->out, 4 * g->w * g->h ); |
| } |
| |
| // clear my history; |
| memset( g->history, 0x00, g->w * g->h ); // pixels that were affected previous frame |
| |
| for (;;) { |
| int tag = stbi__get8(s); |
| switch (tag) { |
| case 0x2C: /* Image Descriptor */ |
| { |
| stbi__int32 x, y, w, h; |
| stbi_uc *o; |
| |
| x = stbi__get16le(s); |
| y = stbi__get16le(s); |
| w = stbi__get16le(s); |
| h = stbi__get16le(s); |
| if (((x + w) > (g->w)) || ((y + h) > (g->h))) |
| return stbi__errpuc("bad Image Descriptor", "Corrupt GIF"); |
| |
| g->line_size = g->w * 4; |
| g->start_x = x * 4; |
| g->start_y = y * g->line_size; |
| g->max_x = g->start_x + w * 4; |
| g->max_y = g->start_y + h * g->line_size; |
| g->cur_x = g->start_x; |
| g->cur_y = g->start_y; |
| |
| g->lflags = stbi__get8(s); |
| |
| if (g->lflags & 0x40) { |
| g->step = 8 * g->line_size; // first interlaced spacing |
| g->parse = 3; |
| } else { |
| g->step = g->line_size; |
| g->parse = 0; |
| } |
| |
| if (g->lflags & 0x80) { |
| stbi__gif_parse_colortable(s,g->lpal, 2 << (g->lflags & 7), g->eflags & 0x01 ? g->transparent : -1); |
| g->color_table = (stbi_uc *) g->lpal; |
| } else if (g->flags & 0x80) { |
| g->color_table = (stbi_uc *) g->pal; |
| } else |
| return stbi__errpuc("missing color table", "Corrupt GIF"); |
| |
| o = stbi__process_gif_raster(s, g); |
| if (o == NULL) return NULL; |
| |
| // if this was the first frame, |
| pcount = g->w * g->h; |
| if (first_frame && (g->bgindex > 0)) { |
| // if first frame, any pixel not drawn to gets the background color |
| for (pi = 0; pi < pcount; ++pi) { |
| if (g->history[pi] == 0) { |
| g->pal[g->bgindex][3] = 255; // just in case it was made transparent, undo that; It will be reset next frame if need be; |
| memcpy( &g->out[pi * 4], &g->pal[g->bgindex], 4 ); |
| } |
| } |
| } |
| |
| return o; |
| } |
| |
| case 0x21: // Comment Extension. |
| { |
| int len; |
| int ext = stbi__get8(s); |
| if (ext == 0xF9) { // Graphic Control Extension. |
| len = stbi__get8(s); |
| if (len == 4) { |
| g->eflags = stbi__get8(s); |
| g->delay = 10 * stbi__get16le(s); // delay - 1/100th of a second, saving as 1/1000ths. |
| |
| // unset old transparent |
| if (g->transparent >= 0) { |
| g->pal[g->transparent][3] = 255; |
| } |
| if (g->eflags & 0x01) { |
| g->transparent = stbi__get8(s); |
| if (g->transparent >= 0) { |
| g->pal[g->transparent][3] = 0; |
| } |
| } else { |
| // don't need transparent |
| stbi__skip(s, 1); |
| g->transparent = -1; |
| } |
| } else { |
| stbi__skip(s, len); |
| break; |
| } |
| } |
| while ((len = stbi__get8(s)) != 0) { |
| stbi__skip(s, len); |
| } |
| break; |
| } |
| |
| case 0x3B: // gif stream termination code |
| return (stbi_uc *) s; // using '1' causes warning on some compilers |
| |
| default: |
| return stbi__errpuc("unknown code", "Corrupt GIF"); |
| } |
| } |
| } |
| |
| static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y, int *z, int *comp, int req_comp) |
| { |
| if (stbi__gif_test(s)) { |
| int layers = 0; |
| stbi_uc *u = 0; |
| stbi_uc *out = 0; |
| stbi_uc *two_back = 0; |
| stbi__gif g; |
| int stride; |
| memset(&g, 0, sizeof(g)); |
| if (delays) { |
| *delays = 0; |
| } |
| |
| do { |
| u = stbi__gif_load_next(s, &g, comp, req_comp, two_back); |
| if (u == (stbi_uc *) s) u = 0; // end of animated gif marker |
| |
| if (u) { |
| *x = g.w; |
| *y = g.h; |
| ++layers; |
| stride = g.w * g.h * 4; |
| |
| if (out) { |
| out = (stbi_uc*) STBI_REALLOC( out, layers * stride ); |
| if (delays) { |
| *delays = (int*) STBI_REALLOC( *delays, sizeof(int) * layers ); |
| } |
| } else { |
| out = (stbi_uc*)stbi__malloc( layers * stride ); |
| if (delays) { |
| *delays = (int*) stbi__malloc( layers * sizeof(int) ); |
| } |
| } |
| memcpy( out + ((layers - 1) * stride), u, stride ); |
| if (layers >= 2) { |
| two_back = out - 2 * stride; |
| } |
| |
| if (delays) { |
| (*delays)[layers - 1U] = g.delay; |
| } |
| } |
| } while (u != 0); |
| |
| // free temp buffer; |
| STBI_FREE(g.out); |
| STBI_FREE(g.history); |
| STBI_FREE(g.background); |
| |
| // do the final conversion after loading everything; |
| if (req_comp && req_comp != 4) |
| out = stbi__convert_format(out, 4, req_comp, layers * g.w, g.h); |
| |
| *z = layers; |
| return out; |
| } else { |
| return stbi__errpuc("not GIF", "Image was not as a gif type."); |
| } |
| } |
| |
| static void *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri) |
| { |
| stbi_uc *u = 0; |
| stbi__gif g; |
| memset(&g, 0, sizeof(g)); |
| STBI_NOTUSED(ri); |
| |
| u = stbi__gif_load_next(s, &g, comp, req_comp, 0); |
| if (u == (stbi_uc *) s) u = 0; // end of animated gif marker |
| if (u) { |
| *x = g.w; |
| *y = g.h; |
| |
| // moved conversion to after successful load so that the same |
| // can be done for multiple frames. |
| if (req_comp && req_comp != 4) |
| u = stbi__convert_format(u, 4, req_comp, g.w, g.h); |
| } |
| |
| // free buffers needed for multiple frame loading; |
| STBI_FREE(g.history); |
| STBI_FREE(g.background); |
| |
| return u; |
| } |
| |
| static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| return stbi__gif_info_raw(s,x,y,comp); |
| } |
| #endif |
| |
| // ************************************************************************************************* |
| // Radiance RGBE HDR loader |
| // originally by Nicolas Schulz |
| #ifndef STBI_NO_HDR |
| static int stbi__hdr_test_core(stbi__context *s, const char *signature) |
| { |
| int i; |
| for (i=0; signature[i]; ++i) |
| if (stbi__get8(s) != signature[i]) |
| return 0; |
| stbi__rewind(s); |
| return 1; |
| } |
| |
| static int stbi__hdr_test(stbi__context* s) |
| { |
| int r = stbi__hdr_test_core(s, "#?RADIANCE\n"); |
| stbi__rewind(s); |
| if(!r) { |
| r = stbi__hdr_test_core(s, "#?RGBE\n"); |
| stbi__rewind(s); |
| } |
| return r; |
| } |
| |
| #define STBI__HDR_BUFLEN 1024 |
| static char *stbi__hdr_gettoken(stbi__context *z, char *buffer) |
| { |
| int len=0; |
| char c = '\0'; |
| |
| c = (char) stbi__get8(z); |
| |
| while (!stbi__at_eof(z) && c != '\n') { |
| buffer[len++] = c; |
| if (len == STBI__HDR_BUFLEN-1) { |
| // flush to end of line |
| while (!stbi__at_eof(z) && stbi__get8(z) != '\n') |
| ; |
| break; |
| } |
| c = (char) stbi__get8(z); |
| } |
| |
| buffer[len] = 0; |
| return buffer; |
| } |
| |
| static void stbi__hdr_convert(float *output, stbi_uc *input, int req_comp) |
| { |
| if ( input[3] != 0 ) { |
| float f1; |
| // Exponent |
| f1 = (float) ldexp(1.0f, input[3] - (int)(128 + 8)); |
| if (req_comp <= 2) |
| output[0] = (input[0] + input[1] + input[2]) * f1 / 3; |
| else { |
| output[0] = input[0] * f1; |
| output[1] = input[1] * f1; |
| output[2] = input[2] * f1; |
| } |
| if (req_comp == 2) output[1] = 1; |
| if (req_comp == 4) output[3] = 1; |
| } else { |
| switch (req_comp) { |
| case 4: output[3] = 1; /* fallthrough */ |
| case 3: output[0] = output[1] = output[2] = 0; |
| break; |
| case 2: output[1] = 1; /* fallthrough */ |
| case 1: output[0] = 0; |
| break; |
| } |
| } |
| } |
| |
| static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri) |
| { |
| char buffer[STBI__HDR_BUFLEN]; |
| char *token; |
| int valid = 0; |
| int width, height; |
| stbi_uc *scanline; |
| float *hdr_data; |
| int len; |
| unsigned char count, value; |
| int i, j, k, c1,c2, z; |
| const char *headerToken; |
| STBI_NOTUSED(ri); |
| |
| // Check identifier |
| headerToken = stbi__hdr_gettoken(s,buffer); |
| if (strcmp(headerToken, "#?RADIANCE") != 0 && strcmp(headerToken, "#?RGBE") != 0) |
| return stbi__errpf("not HDR", "Corrupt HDR image"); |
| |
| // Parse header |
| for(;;) { |
| token = stbi__hdr_gettoken(s,buffer); |
| if (token[0] == 0) break; |
| if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1; |
| } |
| |
| if (!valid) return stbi__errpf("unsupported format", "Unsupported HDR format"); |
| |
| // Parse width and height |
| // can't use sscanf() if we're not using stdio! |
| token = stbi__hdr_gettoken(s,buffer); |
| if (strncmp(token, "-Y ", 3)) return stbi__errpf("unsupported data layout", "Unsupported HDR format"); |
| token += 3; |
| height = (int) strtol(token, &token, 10); |
| while (*token == ' ') ++token; |
| if (strncmp(token, "+X ", 3)) return stbi__errpf("unsupported data layout", "Unsupported HDR format"); |
| token += 3; |
| width = (int) strtol(token, NULL, 10); |
| |
| *x = width; |
| *y = height; |
| |
| if (comp) *comp = 3; |
| if (req_comp == 0) req_comp = 3; |
| |
| if (!stbi__mad4sizes_valid(width, height, req_comp, sizeof(float), 0)) |
| return stbi__errpf("too large", "HDR image is too large"); |
| |
| // Read data |
| hdr_data = (float *) stbi__malloc_mad4(width, height, req_comp, sizeof(float), 0); |
| if (!hdr_data) |
| return stbi__errpf("outofmem", "Out of memory"); |
| |
| // Load image data |
| // image data is stored as some number of sca |
| if ( width < 8 || width >= 32768) { |
| // Read flat data |
| for (j=0; j < height; ++j) { |
| for (i=0; i < width; ++i) { |
| stbi_uc rgbe[4]; |
| main_decode_loop: |
| stbi__getn(s, rgbe, 4); |
| stbi__hdr_convert(hdr_data + j * width * req_comp + i * req_comp, rgbe, req_comp); |
| } |
| } |
| } else { |
| // Read RLE-encoded data |
| scanline = NULL; |
| |
| for (j = 0; j < height; ++j) { |
| c1 = stbi__get8(s); |
| c2 = stbi__get8(s); |
| len = stbi__get8(s); |
| if (c1 != 2 || c2 != 2 || (len & 0x80)) { |
| // not run-length encoded, so we have to actually use THIS data as a decoded |
| // pixel (note this can't be a valid pixel--one of RGB must be >= 128) |
| stbi_uc rgbe[4]; |
| rgbe[0] = (stbi_uc) c1; |
| rgbe[1] = (stbi_uc) c2; |
| rgbe[2] = (stbi_uc) len; |
| rgbe[3] = (stbi_uc) stbi__get8(s); |
| stbi__hdr_convert(hdr_data, rgbe, req_comp); |
| i = 1; |
| j = 0; |
| STBI_FREE(scanline); |
| goto main_decode_loop; // yes, this makes no sense |
| } |
| len <<= 8; |
| len |= stbi__get8(s); |
| if (len != width) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("invalid decoded scanline length", "corrupt HDR"); } |
| if (scanline == NULL) { |
| scanline = (stbi_uc *) stbi__malloc_mad2(width, 4, 0); |
| if (!scanline) { |
| STBI_FREE(hdr_data); |
| return stbi__errpf("outofmem", "Out of memory"); |
| } |
| } |
| |
| for (k = 0; k < 4; ++k) { |
| int nleft; |
| i = 0; |
| while ((nleft = width - i) > 0) { |
| count = stbi__get8(s); |
| if (count > 128) { |
| // Run |
| value = stbi__get8(s); |
| count -= 128; |
| if (count > nleft) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("corrupt", "bad RLE data in HDR"); } |
| for (z = 0; z < count; ++z) |
| scanline[i++ * 4 + k] = value; |
| } else { |
| // Dump |
| if (count > nleft) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("corrupt", "bad RLE data in HDR"); } |
| for (z = 0; z < count; ++z) |
| scanline[i++ * 4 + k] = stbi__get8(s); |
| } |
| } |
| } |
| for (i=0; i < width; ++i) |
| stbi__hdr_convert(hdr_data+(j*width + i)*req_comp, scanline + i*4, req_comp); |
| } |
| if (scanline) |
| STBI_FREE(scanline); |
| } |
| |
| return hdr_data; |
| } |
| |
| static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| char buffer[STBI__HDR_BUFLEN]; |
| char *token; |
| int valid = 0; |
| int dummy; |
| |
| if (!x) x = &dummy; |
| if (!y) y = &dummy; |
| if (!comp) comp = &dummy; |
| |
| if (stbi__hdr_test(s) == 0) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| |
| for(;;) { |
| token = stbi__hdr_gettoken(s,buffer); |
| if (token[0] == 0) break; |
| if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1; |
| } |
| |
| if (!valid) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| token = stbi__hdr_gettoken(s,buffer); |
| if (strncmp(token, "-Y ", 3)) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| token += 3; |
| *y = (int) strtol(token, &token, 10); |
| while (*token == ' ') ++token; |
| if (strncmp(token, "+X ", 3)) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| token += 3; |
| *x = (int) strtol(token, NULL, 10); |
| *comp = 3; |
| return 1; |
| } |
| #endif // STBI_NO_HDR |
| |
| #ifndef STBI_NO_BMP |
| static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| void *p; |
| stbi__bmp_data info; |
| |
| info.all_a = 255; |
| p = stbi__bmp_parse_header(s, &info); |
| stbi__rewind( s ); |
| if (p == NULL) |
| return 0; |
| if (x) *x = s->img_x; |
| if (y) *y = s->img_y; |
| if (comp) *comp = info.ma ? 4 : 3; |
| return 1; |
| } |
| #endif |
| |
| #ifndef STBI_NO_PSD |
| static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| int channelCount, dummy, depth; |
| if (!x) x = &dummy; |
| if (!y) y = &dummy; |
| if (!comp) comp = &dummy; |
| if (stbi__get32be(s) != 0x38425053) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| if (stbi__get16be(s) != 1) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| stbi__skip(s, 6); |
| channelCount = stbi__get16be(s); |
| if (channelCount < 0 || channelCount > 16) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| *y = stbi__get32be(s); |
| *x = stbi__get32be(s); |
| depth = stbi__get16be(s); |
| if (depth != 8 && depth != 16) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| if (stbi__get16be(s) != 3) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| *comp = 4; |
| return 1; |
| } |
| |
| static int stbi__psd_is16(stbi__context *s) |
| { |
| int channelCount, depth; |
| if (stbi__get32be(s) != 0x38425053) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| if (stbi__get16be(s) != 1) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| stbi__skip(s, 6); |
| channelCount = stbi__get16be(s); |
| if (channelCount < 0 || channelCount > 16) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| (void) stbi__get32be(s); |
| (void) stbi__get32be(s); |
| depth = stbi__get16be(s); |
| if (depth != 16) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| return 1; |
| } |
| #endif |
| |
| #ifndef STBI_NO_PIC |
| static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| int act_comp=0,num_packets=0,chained,dummy; |
| stbi__pic_packet packets[10]; |
| |
| if (!x) x = &dummy; |
| if (!y) y = &dummy; |
| if (!comp) comp = &dummy; |
| |
| if (!stbi__pic_is4(s,"\x53\x80\xF6\x34")) { |
| stbi__rewind(s); |
| return 0; |
| } |
| |
| stbi__skip(s, 88); |
| |
| *x = stbi__get16be(s); |
| *y = stbi__get16be(s); |
| if (stbi__at_eof(s)) { |
| stbi__rewind( s); |
| return 0; |
| } |
| if ( (*x) != 0 && (1 << 28) / (*x) < (*y)) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| |
| stbi__skip(s, 8); |
| |
| do { |
| stbi__pic_packet *packet; |
| |
| if (num_packets==sizeof(packets)/sizeof(packets[0])) |
| return 0; |
| |
| packet = &packets[num_packets++]; |
| chained = stbi__get8(s); |
| packet->size = stbi__get8(s); |
| packet->type = stbi__get8(s); |
| packet->channel = stbi__get8(s); |
| act_comp |= packet->channel; |
| |
| if (stbi__at_eof(s)) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| if (packet->size != 8) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| } while (chained); |
| |
| *comp = (act_comp & 0x10 ? 4 : 3); |
| |
| return 1; |
| } |
| #endif |
| |
| // ************************************************************************************************* |
| // Portable Gray Map and Portable Pixel Map loader |
| // by Ken Miller |
| // |
| // PGM: http://netpbm.sourceforge.net/doc/pgm.html |
| // PPM: http://netpbm.sourceforge.net/doc/ppm.html |
| // |
| // Known limitations: |
| // Does not support comments in the header section |
| // Does not support ASCII image data (formats P2 and P3) |
| // Does not support 16-bit-per-channel |
| |
| #ifndef STBI_NO_PNM |
| |
| static int stbi__pnm_test(stbi__context *s) |
| { |
| char p, t; |
| p = (char) stbi__get8(s); |
| t = (char) stbi__get8(s); |
| if (p != 'P' || (t != '5' && t != '6')) { |
| stbi__rewind( s ); |
| return 0; |
| } |
| return 1; |
| } |
| |
| static void *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri) |
| { |
| stbi_uc *out; |
| STBI_NOTUSED(ri); |
| |
| if (!stbi__pnm_info(s, (int *)&s->img_x, (int *)&s->img_y, (int *)&s->img_n)) |
| return 0; |
| |
| *x = s->img_x; |
| *y = s->img_y; |
| if (comp) *comp = s->img_n; |
| |
| if (!stbi__mad3sizes_valid(s->img_n, s->img_x, s->img_y, 0)) |
| return stbi__errpuc("too large", "PNM too large"); |
| |
| out = (stbi_uc *) stbi__malloc_mad3(s->img_n, s->img_x, s->img_y, 0); |
| if (!out) return stbi__errpuc("outofmem", "Out of memory"); |
| stbi__getn(s, out, s->img_n * s->img_x * s->img_y); |
| |
| if (req_comp && req_comp != s->img_n) { |
| out = stbi__convert_format(out, s->img_n, req_comp, s->img_x, s->img_y); |
| if (out == NULL) return out; // stbi__convert_format frees input on failure |
| } |
| return out; |
| } |
| |
| static int stbi__pnm_isspace(char c) |
| { |
| return c == ' ' || c == '\t' || c == '\n' || c == '\v' || c == '\f' || c == '\r'; |
| } |
| |
| static void stbi__pnm_skip_whitespace(stbi__context *s, char *c) |
| { |
| for (;;) { |
| while (!stbi__at_eof(s) && stbi__pnm_isspace(*c)) |
| *c = (char) stbi__get8(s); |
| |
| if (stbi__at_eof(s) || *c != '#') |
| break; |
| |
| while (!stbi__at_eof(s) && *c != '\n' && *c != '\r' ) |
| *c = (char) stbi__get8(s); |
| } |
| } |
| |
| static int stbi__pnm_isdigit(char c) |
| { |
| return c >= '0' && c <= '9'; |
| } |
| |
| static int stbi__pnm_getinteger(stbi__context *s, char *c) |
| { |
| int value = 0; |
| |
| while (!stbi__at_eof(s) && stbi__pnm_isdigit(*c)) { |
| value = value*10 + (*c - '0'); |
| *c = (char) stbi__get8(s); |
| } |
| |
| return value; |
| } |
| |
| static int stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp) |
| { |
| int maxv, dummy; |
| char c, p, t; |
| |
| if (!x) x = &dummy; |
| if (!y) y = &dummy; |
| if (!comp) comp = &dummy; |
| |
| stbi__rewind(s); |
| |
| // Get identifier |
| p = (char) stbi__get8(s); |
| t = (char) stbi__get8(s); |
| if (p != 'P' || (t != '5' && t != '6')) { |
| stbi__rewind(s); |
| return 0; |
| } |
| |
| *comp = (t == '6') ? 3 : 1; // '5' is 1-component .pgm; '6' is 3-component .ppm |
| |
| c = (char) stbi__get8(s); |
| stbi__pnm_skip_whitespace(s, &c); |
| |
| *x = stbi__pnm_getinteger(s, &c); // read width |
| stbi__pnm_skip_whitespace(s, &c); |
| |
| *y = stbi__pnm_getinteger(s, &c); // read height |
| stbi__pnm_skip_whitespace(s, &c); |
| |
| maxv = stbi__pnm_getinteger(s, &c); // read max value |
| |
| if (maxv > 255) |
| return stbi__err("max value > 255", "PPM image not 8-bit"); |
| else |
| return 1; |
| } |
| #endif |
| |
| static int stbi__info_main(stbi__context *s, int *x, int *y, int *comp) |
| { |
| #ifndef STBI_NO_JPEG |
| if (stbi__jpeg_info(s, x, y, comp)) return 1; |
| #endif |
| |
| #ifndef STBI_NO_PNG |
| if (stbi__png_info(s, x, y, comp)) return 1; |
| #endif |
| |
| #ifndef STBI_NO_GIF |
| if (stbi__gif_info(s, x, y, comp)) return 1; |
| #endif |
| |
| #ifndef STBI_NO_BMP |
| if (stbi__bmp_info(s, x, y, comp)) return 1; |
| #endif |
| |
| #ifndef STBI_NO_PSD |
| if (stbi__psd_info(s, x, y, comp)) return 1; |
| #endif |
| |
| #ifndef STBI_NO_PIC |
| if (stbi__pic_info(s, x, y, comp)) return 1; |
| #endif |
| |
| #ifndef STBI_NO_PNM |
| if (stbi__pnm_info(s, x, y, comp)) return 1; |
| #endif |
| |
| #ifndef STBI_NO_HDR |
| if (stbi__hdr_info(s, x, y, comp)) return 1; |
| #endif |
| |
| // test tga last because it's a crappy test! |
| #ifndef STBI_NO_TGA |
| if (stbi__tga_info(s, x, y, comp)) |
| return 1; |
| #endif |
| return stbi__err("unknown image type", "Image not of any known type, or corrupt"); |
| } |
| |
| static int stbi__is_16_main(stbi__context *s) |
| { |
| #ifndef STBI_NO_PNG |
| if (stbi__png_is16(s)) return 1; |
| #endif |
| |
| #ifndef STBI_NO_PSD |
| if (stbi__psd_is16(s)) return 1; |
| #endif |
| |
| return 0; |
| } |
| |
| #ifndef STBI_NO_STDIO |
| STBIDEF int stbi_info(char const *filename, int *x, int *y, int *comp) |
| { |
| FILE *f = stbi__fopen(filename, "rb"); |
| int result; |
| if (!f) return stbi__err("can't fopen", "Unable to open file"); |
| result = stbi_info_from_file(f, x, y, comp); |
| fclose(f); |
| return result; |
| } |
| |
| STBIDEF int stbi_info_from_file(FILE *f, int *x, int *y, int *comp) |
| { |
| int r; |
| stbi__context s; |
| long pos = ftell(f); |
| stbi__start_file(&s, f); |
| r = stbi__info_main(&s,x,y,comp); |
| fseek(f,pos,SEEK_SET); |
| return r; |
| } |
| |
| STBIDEF int stbi_is_16_bit(char const *filename) |
| { |
| FILE *f = stbi__fopen(filename, "rb"); |
| int result; |
| if (!f) return stbi__err("can't fopen", "Unable to open file"); |
| result = stbi_is_16_bit_from_file(f); |
| fclose(f); |
| return result; |
| } |
| |
| STBIDEF int stbi_is_16_bit_from_file(FILE *f) |
| { |
| int r; |
| stbi__context s; |
| long pos = ftell(f); |
| stbi__start_file(&s, f); |
| r = stbi__is_16_main(&s); |
| fseek(f,pos,SEEK_SET); |
| return r; |
| } |
| #endif // !STBI_NO_STDIO |
| |
| STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp) |
| { |
| stbi__context s; |
| stbi__start_mem(&s,buffer,len); |
| return stbi__info_main(&s,x,y,comp); |
| } |
| |
| STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *c, void *user, int *x, int *y, int *comp) |
| { |
| stbi__context s; |
| stbi__start_callbacks(&s, (stbi_io_callbacks *) c, user); |
| return stbi__info_main(&s,x,y,comp); |
| } |
| |
| STBIDEF int stbi_is_16_bit_from_memory(stbi_uc const *buffer, int len) |
| { |
| stbi__context s; |
| stbi__start_mem(&s,buffer,len); |
| return stbi__is_16_main(&s); |
| } |
| |
| STBIDEF int stbi_is_16_bit_from_callbacks(stbi_io_callbacks const *c, void *user) |
| { |
| stbi__context s; |
| stbi__start_callbacks(&s, (stbi_io_callbacks *) c, user); |
| return stbi__is_16_main(&s); |
| } |
| |
| #endif // STB_IMAGE_IMPLEMENTATION |
| |
| /* |
| revision history: |
| 2.20 (2019-02-07) support utf8 filenames in Windows; fix warnings and platform ifdefs |
| 2.19 (2018-02-11) fix warning |
| 2.18 (2018-01-30) fix warnings |
| 2.17 (2018-01-29) change sbti__shiftsigned to avoid clang -O2 bug |
| 1-bit BMP |
| *_is_16_bit api |
| avoid warnings |
| 2.16 (2017-07-23) all functions have 16-bit variants; |
| STBI_NO_STDIO works again; |
| compilation fixes; |
| fix rounding in unpremultiply; |
| optimize vertical flip; |
| disable raw_len validation; |
| documentation fixes |
| 2.15 (2017-03-18) fix png-1,2,4 bug; now all Imagenet JPGs decode; |
| warning fixes; disable run-time SSE detection on gcc; |
| uniform handling of optional "return" values; |
| thread-safe initialization of zlib tables |
| 2.14 (2017-03-03) remove deprecated STBI_JPEG_OLD; fixes for Imagenet JPGs |
| 2.13 (2016-11-29) add 16-bit API, only supported for PNG right now |
| 2.12 (2016-04-02) fix typo in 2.11 PSD fix that caused crashes |
| 2.11 (2016-04-02) allocate large structures on the stack |
| remove white matting for transparent PSD |
| fix reported channel count for PNG & BMP |
| re-enable SSE2 in non-gcc 64-bit |
| support RGB-formatted JPEG |
| read 16-bit PNGs (only as 8-bit) |
| 2.10 (2016-01-22) avoid warning introduced in 2.09 by STBI_REALLOC_SIZED |
| 2.09 (2016-01-16) allow comments in PNM files |
| 16-bit-per-pixel TGA (not bit-per-component) |
| info() for TGA could break due to .hdr handling |
| info() for BMP to shares code instead of sloppy parse |
| can use STBI_REALLOC_SIZED if allocator doesn't support realloc |
| code cleanup |
| 2.08 (2015-09-13) fix to 2.07 cleanup, reading RGB PSD as RGBA |
| 2.07 (2015-09-13) fix compiler warnings |
| partial animated GIF support |
| limited 16-bpc PSD support |
| #ifdef unused functions |
| bug with < 92 byte PIC,PNM,HDR,TGA |
| 2.06 (2015-04-19) fix bug where PSD returns wrong '*comp' value |
| 2.05 (2015-04-19) fix bug in progressive JPEG handling, fix warning |
| 2.04 (2015-04-15) try to re-enable SIMD on MinGW 64-bit |
| 2.03 (2015-04-12) extra corruption checking (mmozeiko) |
| stbi_set_flip_vertically_on_load (nguillemot) |
| fix NEON support; fix mingw support |
| 2.02 (2015-01-19) fix incorrect assert, fix warning |
| 2.01 (2015-01-17) fix various warnings; suppress SIMD on gcc 32-bit without -msse2 |
| 2.00b (2014-12-25) fix STBI_MALLOC in progressive JPEG |
| 2.00 (2014-12-25) optimize JPG, including x86 SSE2 & NEON SIMD (ryg) |
| progressive JPEG (stb) |
| PGM/PPM support (Ken Miller) |
| STBI_MALLOC,STBI_REALLOC,STBI_FREE |
| GIF bugfix -- seemingly never worked |
| STBI_NO_*, STBI_ONLY_* |
| 1.48 (2014-12-14) fix incorrectly-named assert() |
| 1.47 (2014-12-14) 1/2/4-bit PNG support, both direct and paletted (Omar Cornut & stb) |
| optimize PNG (ryg) |
| fix bug in interlaced PNG with user-specified channel count (stb) |
| 1.46 (2014-08-26) |
| fix broken tRNS chunk (colorkey-style transparency) in non-paletted PNG |
| 1.45 (2014-08-16) |
| fix MSVC-ARM internal compiler error by wrapping malloc |
| 1.44 (2014-08-07) |
| various warning fixes from Ronny Chevalier |
| 1.43 (2014-07-15) |
| fix MSVC-only compiler problem in code changed in 1.42 |
| 1.42 (2014-07-09) |
| don't define _CRT_SECURE_NO_WARNINGS (affects user code) |
| fixes to stbi__cleanup_jpeg path |
| added STBI_ASSERT to avoid requiring assert.h |
| 1.41 (2014-06-25) |
| fix search&replace from 1.36 that messed up comments/error messages |
| 1.40 (2014-06-22) |
| fix gcc struct-initialization warning |
| 1.39 (2014-06-15) |
| fix to TGA optimization when req_comp != number of components in TGA; |
| fix to GIF loading because BMP wasn't rewinding (whoops, no GIFs in my test suite) |
| add support for BMP version 5 (more ignored fields) |
| 1.38 (2014-06-06) |
| suppress MSVC warnings on integer casts truncating values |
| fix accidental rename of 'skip' field of I/O |
| 1.37 (2014-06-04) |
| remove duplicate typedef |
| 1.36 (2014-06-03) |
| convert to header file single-file library |
| if de-iphone isn't set, load iphone images color-swapped instead of returning NULL |
| 1.35 (2014-05-27) |
| various warnings |
| fix broken STBI_SIMD path |
| fix bug where stbi_load_from_file no longer left file pointer in correct place |
| fix broken non-easy path for 32-bit BMP (possibly never used) |
| TGA optimization by Arseny Kapoulkine |
| 1.34 (unknown) |
| use STBI_NOTUSED in stbi__resample_row_generic(), fix one more leak in tga failure case |
| 1.33 (2011-07-14) |
| make stbi_is_hdr work in STBI_NO_HDR (as specified), minor compiler-friendly improvements |
| 1.32 (2011-07-13) |
| support for "info" function for all supported filetypes (SpartanJ) |
| 1.31 (2011-06-20) |
| a few more leak fixes, bug in PNG handling (SpartanJ) |
| 1.30 (2011-06-11) |
| added ability to load files via callbacks to accomidate custom input streams (Ben Wenger) |
| removed deprecated format-specific test/load functions |
| removed support for installable file formats (stbi_loader) -- would have been broken for IO callbacks anyway |
| error cases in bmp and tga give messages and don't leak (Raymond Barbiero, grisha) |
| fix inefficiency in decoding 32-bit BMP (David Woo) |
| 1.29 (2010-08-16) |
| various warning fixes from Aurelien Pocheville |
| 1.28 (2010-08-01) |
| fix bug in GIF palette transparency (SpartanJ) |
| 1.27 (2010-08-01) |
| cast-to-stbi_uc to fix warnings |
| 1.26 (2010-07-24) |
| fix bug in file buffering for PNG reported by SpartanJ |
| 1.25 (2010-07-17) |
| refix trans_data warning (Won Chun) |
| 1.24 (2010-07-12) |
| perf improvements reading from files on platforms with lock-heavy fgetc() |
| minor perf improvements for jpeg |
| deprecated type-specific functions so we'll get feedback if they're needed |
| attempt to fix trans_data warning (Won Chun) |
| 1.23 fixed bug in iPhone support |
| 1.22 (2010-07-10) |
| removed image *writing* support |
| stbi_info support from Jetro Lauha |
| GIF support from Jean-Marc Lienher |
| iPhone PNG-extensions from James Brown |
| warning-fixes from Nicolas Schulz and Janez Zemva (i.stbi__err. Janez (U+017D)emva) |
| 1.21 fix use of 'stbi_uc' in header (reported by jon blow) |
| 1.20 added support for Softimage PIC, by Tom Seddon |
| 1.19 bug in interlaced PNG corruption check (found by ryg) |
| 1.18 (2008-08-02) |
| fix a threading bug (local mutable static) |
| 1.17 support interlaced PNG |
| 1.16 major bugfix - stbi__convert_format converted one too many pixels |
| 1.15 initialize some fields for thread safety |
| 1.14 fix threadsafe conversion bug |
| header-file-only version (#define STBI_HEADER_FILE_ONLY before including) |
| 1.13 threadsafe |
| 1.12 const qualifiers in the API |
| 1.11 Support installable IDCT, colorspace conversion routines |
| 1.10 Fixes for 64-bit (don't use "unsigned long") |
| optimized upsampling by Fabian "ryg" Giesen |
| 1.09 Fix format-conversion for PSD code (bad global variables!) |
| 1.08 Thatcher Ulrich's PSD code integrated by Nicolas Schulz |
| 1.07 attempt to fix C++ warning/errors again |
| 1.06 attempt to fix C++ warning/errors again |
| 1.05 fix TGA loading to return correct *comp and use good luminance calc |
| 1.04 default float alpha is 1, not 255; use 'void *' for stbi_image_free |
| 1.03 bugfixes to STBI_NO_STDIO, STBI_NO_HDR |
| 1.02 support for (subset of) HDR files, float interface for preferred access to them |
| 1.01 fix bug: possible bug in handling right-side up bmps... not sure |
| fix bug: the stbi__bmp_load() and stbi__tga_load() functions didn't work at all |
| 1.00 interface to zlib that skips zlib header |
| 0.99 correct handling of alpha in palette |
| 0.98 TGA loader by lonesock; dynamically add loaders (untested) |
| 0.97 jpeg errors on too large a file; also catch another malloc failure |
| 0.96 fix detection of invalid v value - particleman@mollyrocket forum |
| 0.95 during header scan, seek to markers in case of padding |
| 0.94 STBI_NO_STDIO to disable stdio usage; rename all #defines the same |
| 0.93 handle jpegtran output; verbose errors |
| 0.92 read 4,8,16,24,32-bit BMP files of several formats |
| 0.91 output 24-bit Windows 3.0 BMP files |
| 0.90 fix a few more warnings; bump version number to approach 1.0 |
| 0.61 bugfixes due to Marc LeBlanc, Christopher Lloyd |
| 0.60 fix compiling as c++ |
| 0.59 fix warnings: merge Dave Moore's -Wall fixes |
| 0.58 fix bug: zlib uncompressed mode len/nlen was wrong endian |
| 0.57 fix bug: jpg last huffman symbol before marker was >9 bits but less than 16 available |
| 0.56 fix bug: zlib uncompressed mode len vs. nlen |
| 0.55 fix bug: restart_interval not initialized to 0 |
| 0.54 allow NULL for 'int *comp' |
| 0.53 fix bug in png 3->4; speedup png decoding |
| 0.52 png handles req_comp=3,4 directly; minor cleanup; jpeg comments |
| 0.51 obey req_comp requests, 1-component jpegs return as 1-component, |
| on 'test' only check type, not whether we support this variant |
| 0.50 (2006-11-19) |
| first released version |
| */ |
| |
| |
| /* |
| ------------------------------------------------------------------------------ |
| This software is available under 2 licenses -- choose whichever you prefer. |
| ------------------------------------------------------------------------------ |
| ALTERNATIVE A - MIT License |
| Copyright (c) 2017 Sean Barrett |
| Permission is hereby granted, free of charge, to any person obtaining a copy of |
| this software and associated documentation files (the "Software"), to deal in |
| the Software without restriction, including without limitation the rights to |
| use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies |
| of the Software, and to permit persons to whom the Software is furnished to do |
| so, subject to the following conditions: |
| The above copyright notice and this permission notice shall be included in all |
| copies or substantial portions of the Software. |
| THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| SOFTWARE. |
| ------------------------------------------------------------------------------ |
| ALTERNATIVE B - Public Domain (www.unlicense.org) |
| This is free and unencumbered software released into the public domain. |
| Anyone is free to copy, modify, publish, use, compile, sell, or distribute this |
| software, either in source code form or as a compiled binary, for any purpose, |
| commercial or non-commercial, and by any means. |
| In jurisdictions that recognize copyright laws, the author or authors of this |
| software dedicate any and all copyright interest in the software to the public |
| domain. We make this dedication for the benefit of the public at large and to |
| the detriment of our heirs and successors. We intend this dedication to be an |
| overt act of relinquishment in perpetuity of all present and future rights to |
| this software under copyright law. |
| THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN |
| ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
| WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| ------------------------------------------------------------------------------ |
| */ |
