[libpng16] Add palette support to the simplified APIs. This commit
changes some of the macro definitions in png.h, app code may need
corresponding changes.
diff --git a/ANNOUNCE b/ANNOUNCE
index 1057fee..1b3008d 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
-Libpng 1.6.0beta05 - January 15, 2012
+Libpng 1.6.0beta06 - January 16, 2012
This is not intended to be a public release. It will be replaced
within a few weeks by a public version or by another test version.
@@ -9,20 +9,20 @@
Source files with LF line endings (for Unix/Linux) and with a
"configure" script
- 1.6.0beta05.tar.xz (LZMA-compressed, recommended)
- 1.6.0beta05.tar.gz
- 1.6.0beta05.tar.bz2
+ 1.6.0beta06.tar.xz (LZMA-compressed, recommended)
+ 1.6.0beta06.tar.gz
+ 1.6.0beta06.tar.bz2
Source files with CRLF line endings (for Windows), without the
"configure" script
- lp160b05.7z (LZMA-compressed, recommended)
- lp160b05.zip
+ lp160b06.7z (LZMA-compressed, recommended)
+ lp160b06.zip
Other information:
- 1.6.0beta05-README.txt
- 1.6.0beta05-LICENSE.txt
+ 1.6.0beta06-README.txt
+ 1.6.0beta06-LICENSE.txt
Changes since the last public release (1.5.7):
@@ -109,6 +109,11 @@
Fix bug in pngerror.c: some long warnings were being improperly truncated
(bug introduced in libpng-1.5.3beta05).
+Version 1.6.0beta06 [January 16, 2012]
+ Add palette support to the simplified APIs. This commit
+ changes some of the macro definitions in png.h, app code
+ may need corresponding changes.
+
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
(subscription required; visit
https://lists.sourceforge.net/lists/listinfo/png-mng-implement
diff --git a/CHANGES b/CHANGES
index b83ff8c..1a81df2 100644
--- a/CHANGES
+++ b/CHANGES
@@ -3860,6 +3860,11 @@
Fix bug in pngerror.c: some long warnings were being improperly truncated
(bug introduced in libpng-1.5.3beta05).
+Version 1.6.0beta06 [January 16, 2012]
+ Add palette support to the simplified APIs. This commit
+ changes some of the macro definitions in png.h, app code
+ may need corresponding changes.
+
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
(subscription required; visit
https://lists.sourceforge.net/lists/listinfo/png-mng-implement
diff --git a/png.c b/png.c
index 0de50e8..21c6aa9 100644
--- a/png.c
+++ b/png.c
@@ -14,7 +14,7 @@
#include "pngpriv.h"
/* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_0beta05 Your_png_h_is_not_version_1_6_0beta05;
+typedef png_libpng_version_1_6_0beta06 Your_png_h_is_not_version_1_6_0beta06;
/* Tells libpng that we have already handled the first "num_bytes" bytes
* of the PNG file signature. If the PNG data is embedded into another
@@ -762,13 +762,13 @@
#else
# ifdef __STDC__
return PNG_STRING_NEWLINE \
- "libpng version 1.6.0beta05 - January 15, 2012" PNG_STRING_NEWLINE \
+ "libpng version 1.6.0beta06 - January 16, 2012" PNG_STRING_NEWLINE \
"Copyright (c) 1998-2012 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
"Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
"Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
PNG_STRING_NEWLINE;
# else
- return "libpng version 1.6.0beta05 - January 15, 2012\
+ return "libpng version 1.6.0beta06 - January 16, 2012\
Copyright (c) 1998-2012 Glenn Randers-Pehrson\
Copyright (c) 1996-1997 Andreas Dilger\
Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
@@ -3221,7 +3221,7 @@
{
/* Utility to log an error. */
png_safecat(image->message, sizeof image->message, 0, error_message);
- image->warning_or_error = 1;
+ image->warning_or_error |= PNG_IMAGE_ERROR;
png_image_free(image);
return 0;
}
diff --git a/png.h b/png.h
index f665439..f99b6d6 100644
--- a/png.h
+++ b/png.h
@@ -1,7 +1,7 @@
/* png.h - header file for PNG reference library
*
- * libpng version 1.6.0beta05 - January 15, 2012
+ * libpng version 1.6.0beta06 - January 16, 2012
* Copyright (c) 1998-2012 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -11,7 +11,7 @@
* Authors and maintainers:
* libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
* libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- * libpng versions 0.97, January 1998, through 1.6.0beta05 - January 15, 2012: Glenn
+ * libpng versions 0.97, January 1998, through 1.6.0beta06 - January 16, 2012: Glenn
* See also "Contributing Authors", below.
*
* Note about libpng version numbers:
@@ -166,7 +166,7 @@
* 1.5.7beta01-05 15 10507 15.so.15.7[.0]
* 1.5.7rc01-03 15 10507 15.so.15.7[.0]
* 1.5.7 15 10507 15.so.15.7[.0]
- * 1.6.0beta01-05 16 10600 16.so.16.0[.0]
+ * 1.6.0beta01-06 16 10600 16.so.16.0[.0]
*
* Henceforth the source version will match the shared-library major
* and minor numbers; the shared-library major version number will be
@@ -198,7 +198,7 @@
*
* This code is released under the libpng license.
*
- * libpng versions 1.2.6, August 15, 2004, through 1.6.0beta05, January 15, 2012, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.6.0beta06, January 16, 2012, are
* Copyright (c) 2004, 2006-2012 Glenn Randers-Pehrson, and are
* distributed according to the same disclaimer and license as libpng-1.2.5
* with the following individual added to the list of Contributing Authors:
@@ -310,13 +310,13 @@
* Y2K compliance in libpng:
* =========================
*
- * January 15, 2012
+ * January 16, 2012
*
* Since the PNG Development group is an ad-hoc body, we can't make
* an official declaration.
*
* This is your unofficial assurance that libpng from version 0.71 and
- * upward through 1.6.0beta05 are Y2K compliant. It is my belief that
+ * upward through 1.6.0beta06 are Y2K compliant. It is my belief that
* earlier versions were also Y2K compliant.
*
* Libpng only has two year fields. One is a 2-byte unsigned integer
@@ -374,9 +374,9 @@
*/
/* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.6.0beta05"
+#define PNG_LIBPNG_VER_STRING "1.6.0beta06"
#define PNG_HEADER_VERSION_STRING \
- " libpng version 1.6.0beta05 - January 15, 2012\n"
+ " libpng version 1.6.0beta06 - January 16, 2012\n"
#define PNG_LIBPNG_VER_SONUM 16
#define PNG_LIBPNG_VER_DLLNUM 16
@@ -390,7 +390,7 @@
* PNG_LIBPNG_VER_STRING, omitting any leading zero:
*/
-#define PNG_LIBPNG_VER_BUILD 05
+#define PNG_LIBPNG_VER_BUILD 06
/* Release Status */
#define PNG_LIBPNG_BUILD_ALPHA 1
@@ -520,7 +520,7 @@
/* This triggers a compiler error in png.c, if png.c and png.h
* do not agree upon the version number.
*/
-typedef char* png_libpng_version_1_6_0beta05;
+typedef char* png_libpng_version_1_6_0beta06;
/* Basic control structions. Read libpng-manual.txt or libpng.3 for more info.
*
@@ -2637,29 +2637,34 @@
* To read a PNG file using the simplified API:
*
* 1) Declare a 'png_image' structure (see below) on the stack and memset() it
- * to all zero.
+ * to all zero.
* 2) Call the appropriate png_image_begin_read... function.
- * 3) Set the png_image 'format' member to the required format and allocate a
- * buffer for the image.
- * 4) Call png_image_finish_read to read the image into your buffer.
+ * 3) Set the png_image 'format' member to the required sample format.
+ * 4) [Optionally] Call png_image_read_colormap to read the image color-map and
+ * request return of a color-mapped image.
+ * 5) Allocate a buffer for the image.
+ * 6) Call png_image_finish_read to read the image into your buffer.
*
* There are no restrictions on the format of the PNG input itself; all valid
* color types, bit depths, and interlace methods are acceptable, and the
* input image is transformed as necessary to the requested in-memory format
- * during the png_image_finish_read() step.
+ * during the png_image_finish_read() step. The only caveat is that if you
+ * request a color-mapped image from a PNG that was not originally color-mapped
+ * the transformation is extremely lossy and the result may look terrible.
*
* To write a PNG file using the simplified API:
*
* 1) Declare a 'png_image' structure on the stack and memset() it to all zero.
* 2) Initialize the members of the structure that describe the image, setting
- * the 'format' member to the format of the image in memory.
- * 3) Call the appropriate png_image_write... function with a pointer to the
- * image to write the PNG data.
+ * the 'format' member to the format of the image samples.
+ * 3) [Optionally] call png_image_write_colormap to set the image color-map if
+ * the data to be written is color-mapped.
+ * 4) Call the appropriate png_image_write... function with a pointer to the
+ * image to write the PNG data.
*
* png_image is a structure that describes the in-memory format of an image
* when it is being read or define the in-memory format of an image that you
* need to write:
- *
*/
typedef struct png_control *png_controlp;
@@ -2671,18 +2676,33 @@
png_uint_32 flags; /* A bit mask containing informational flags */
png_controlp opaque; /* Initialize to NULL, free with png_image_free */
+ /* The following is only used for write; initialize it to NULL */
+ png_const_bytep colormap; /* A pointer to the application color-map */
+
/* In the event of an error or warning the following field will be set to a
* non-zero value and the 'message' field will contain a '\0' terminated
* string with the libpng error or warning message. If both warnings and
* an error were encountered, only the error is recorded. If there
* are multiple warnings, only the first one is recorded.
*
- * As of libpng-1.5.7 the values are
- * 0 - no warning or error
- * 1 - error
- * 2 - warning
+ * The upper 30 bits of this value are reserved, the low two bits contain
+ * a value as follows:
*/
+# define PNG_IMAGE_WARNING 1
+# define PNG_IMAGE_ERROR 2
+ /*
+ * The result is a two bit code such that a value more than 1 indicates
+ * a failure in the API just called:
+ *
+ * 0 - no warning or error
+ * 1 - warning
+ * 2 - error
+ * 3 - error preceded by warning
+ */
+# define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1)
+
png_uint_32 warning_or_error;
+
char message[64];
} png_image, *png_imagep;
@@ -2696,7 +2716,7 @@
*
* The channels are encoded in one of two ways:
*
- * a) As a small integer, value 0..255, contained in a (png_byte). For the
+ * a) As a small integer, value 0..255, contained in a single byte. For the
* alpha channel the original value is simply value/255. For the color or
* luminance channels the value is encoded according to the sRGB specification
* and matches the 8-bit format expected by typical display devices.
@@ -2704,7 +2724,7 @@
* The color/gray channels are not scaled (pre-multiplied) by the alpha
* channel and are suitable for passing to color management software.
*
- * b) As a value in the range 0..65535, contained in a (png_uint_16). All
+ * b) As a value in the range 0..65535, contained in a 2-byte integer. All
* channels can be converted to the original value by dividing by 65535; all
* channels are linear. Color channels use the RGB encoding (RGB end-points) of
* the sRGB specification. This encoding is identified by the
@@ -2714,6 +2734,12 @@
* of the color or luminance channels and is returned as an associated alpha
* channel: the color/gray channels are scaled (pre-multiplied) by the alpha
* value.
+ *
+ * When a color-mapped image is used as a result of calling
+ * png_image_read_colormap or png_image_write_colormap the channels are encoded
+ * in the color-map and the descriptions above apply to the color-map entries.
+ * The image data is encoded as small integers, value 0..255, that index the
+ * entries in the color-map. One integer (one byte) is stored for each pixel.
*/
/* PNG_FORMAT_*
@@ -2726,6 +2752,11 @@
* valid: use the bit flag values below for testing a format returned by the
* read APIs, but set formats from the derived values.
*
+ * When reading or writing color-mapped images the format should be set to the
+ * format of the entries in the color-map then png_image_{read,write}_colormap
+ * called to read or write the color-map and set the format correctly for the
+ * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly!
+ *
* NOTE: libpng can be built with particular features disabled, if you see
* compiler errors because the definition of one of the following flags has been
* compiled out it is because libpng does not have the required support. It is
@@ -2735,22 +2766,24 @@
*
* PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED
*/
-#define PNG_FORMAT_FLAG_ALPHA 0x01 /* format with an alpha channel */
-#define PNG_FORMAT_FLAG_COLOR 0x02 /* color format: otherwise grayscale */
-#define PNG_FORMAT_FLAG_LINEAR 0x04 /* png_uint_16 channels else png_byte */
+#define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */
+#define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */
+#define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2 byte channels else 1 byte */
+#define PNG_FORMAT_FLAG_COLORMAP 0x08U /* libpng use only */
#ifdef PNG_FORMAT_BGR_SUPPORTED
-# define PNG_FORMAT_FLAG_BGR 0x08 /* BGR colors, else order is RGB */
+# define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */
#endif
#ifdef PNG_FORMAT_AFIRST_SUPPORTED
-# define PNG_FORMAT_FLAG_AFIRST 0x10 /* alpha channel comes first */
+# define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */
#endif
/* Supported formats are as follows. Future versions of libpng may support more
* formats; for compatibility with older versions simply check if the format
* macro is defined using #ifdef. These defines describe the in-memory layout
- * of the components of the pixels of the image.
+ * of the components of the pixels of the image or, for color-mapped images, the
+ * layout of the entries of the color-map.
*
* First the single byte formats:
*/
@@ -2764,7 +2797,7 @@
#define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA)
#define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST)
-/* Then the linear (png_uint_16) formats. When naming these "Y" is used to
+/* Then the linear 2-byte formats. When naming these "Y" is used to
* indicate a luminance (gray) channel. The component order within the pixel
* is always the same - there is no provision for swapping the order of the
* components in the linear format.
@@ -2775,31 +2808,86 @@
#define PNG_FORMAT_LINEAR_RGB_ALPHA \
(PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA)
+/* Color-mapped formats are obtained by calling png_image_{read,write}_colormap,
+ * as appropriate after setting png_image::format to the format of the color-map
+ * to be read or written. Applications may check the value of
+ * PNG_FORMAT_FLAG_COLORMAP to see if they have called the colormap API. The
+ * format of the color-map may be extracted using the following macro.
+ */
+#define PNG_FORMAT_OF_COLORMAP(fmt) ((fmt) & ~PNG_FORMAT_FLAG_COLORMAP)
+
/* PNG_IMAGE macros
*
- * These are convenience macros to derive information from a png_image structure
+ * These are convenience macros to derive information from a png_image
+ * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the
+ * actual image sample values - either the entries in the color-map or the
+ * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values
+ * for the pixels and will always return 1 after a call to
+ * png_image_{read,write}_colormap. The remaining macros return information
+ * about the rows in the image and the complete image.
+ *
+ * NOTE: All the macros that take a png_image::format parameter are compile time
+ * constants if the format parameter is, itself, a constant. Therefore these
+ * macros can be used in array declarations and case labels where required.
+ * Similarly the macros are also pre-processor constants (sizeof is not used) so
+ * they can be used in #if tests.
+ *
+ * First the information about the samples.
*/
-#define PNG_IMAGE_CHANNELS(fmt)\
- (1+((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA)))
+#define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\
+ (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1)
/* Return the total number of channels in a given format: 1..4 */
-#define PNG_IMAGE_COMPONENT_SIZE(fmt)\
- (((fmt) & PNG_FORMAT_FLAG_LINEAR) ? sizeof (png_uint_16) : sizeof (png_byte))
- /* Return the size in bytes of a single component of a pixel in the image. */
+#define PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)\
+ ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1)
+ /* Return the size in bytes of a single component of a pixel or color-map
+ * entry (as appropriate) in the image.
+ */
-#define PNG_IMAGE_PIXEL_SIZE(fmt)\
- (PNG_IMAGE_CHANNELS(fmt) * PNG_IMAGE_COMPONENT_SIZE(fmt))
- /* Return the size in bytes of a single pixel in the image. */
-
+#define PNG_IMAGE_SAMPLE_SIZE(fmt)\
+ (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt))
+ /* This is the size of the sample data for one sample. If the image is
+ * color-mapped it is the size of one color-map entry (and image pixels are
+ * one byte in size), otherwise it is the size of one image pixel.
+ */
+
+#define PNG_IMAGE_COLORMAP_SIZE(fmt) (PNG_IMAGE_SAMPLE_SIZE(format) * 256)
+ /* The size of the color-map required by the format; this is the size of the
+ * color-map buffer passed to the png_image_{read,write}_colormap APIs, it is
+ * a fixed number determined by the format so can easily be allocated on the
+ * stack if necessary.
+ */
+
+/* Corresponding information about the pixels */
+#define PNG_IMAGE_PIXEL_(test,fmt)\
+ (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt))
+
+#define PNG_IMAGE_PIXEL_CHANNELS(fmt)\
+ PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt)
+ /* The number of separate channels (components) in a pixel; 1 for a
+ * color-mapped image.
+ */
+
+#define PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)\
+ PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt)
+ /* The size, in bytes, of each component in a pixel; 1 for a color-mapped
+ * image.
+ */
+
+#define PNG_IMAGE_PIXEL_SIZE(fmt) PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_SIZE,fmt)
+ /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */
+
+/* Information about the whole row, or whole image */
#define PNG_IMAGE_ROW_STRIDE(image)\
- (PNG_IMAGE_CHANNELS((image).format) * (image).width)
+ (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width)
/* Return the total number of components in a single row of the image; this
* is the minimum 'row stride', the minimum count of components between each
+ * row. For a color-mapped image this is the minimum number of bytes in a
* row.
*/
#define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\
- (PNG_IMAGE_COMPONENT_SIZE((image).format) * (image).height * (row_stride))
+ (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride))
/* Return the size, in bytes, of an image buffer given a png_image and a row
* stride - the number of components to leave space for in each row.
*/
@@ -2815,17 +2903,24 @@
* Flags containing additional information about the image are held in the
* 'flags' field of png_image.
*/
-#define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 1
+#define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01
/* This indicates the the RGB values of the in-memory bitmap do not
* correspond to the red, green and blue end-points defined by sRGB.
*/
+#define PNG_IMAGE_FLAG_COLORMAP 0x02
+ /* The PNG is color-mapped. If this flag is set png_image_read_colormap
+ * can be used without further loss of image information. If it is not set
+ * png_image_read_colormap will cause significant loss if the image has any
+ * colors (if PNG_FORMAT_FLAG_COLOR is set).
+ */
+
#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
/* READ APIs
* ---------
*
* The png_image passed to the read APIs must have been initialized by setting
- * the png_controlp field 'opaque' to NULL (or, better, memset the whole thing.)
+ * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.)
*/
#ifdef PNG_STDIO_SUPPORTED
PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image,
@@ -2843,12 +2938,32 @@
png_const_voidp memory, png_size_t size));
/* The PNG header is read from the given memory buffer. */
+PNG_EXPORT(242, int, png_image_read_colormap, (png_imagep image,
+ png_bytep colormap, png_colorp background));
+ /* Set the png_image to read a color-mapped image. image->format must be set
+ * to the format required for the color-map, typically PNG_FORMAT_RGBA or
+ * just PNG_FORMAT_RGB if an alpha channel is to be removed.
+ *
+ * The color-map is filled in and the actual number of valid entries
+ * returned, 0 is returned on error. A subsequent call to
+ * png_image_finish_read will return the color-mapped image data; one byte
+ * per pixel.
+ *
+ * background is used as described below to remove alpha or transparency
+ * information from an 8-bit color-map by compositing onto a solid color.
+ *
+ * If background is NULL *and* PNG_FORMAT_RGB is requested *and* the input
+ * has an alpha channel then the call will currently FAIL, however, in the
+ * future, libpng may be extended to composite onto the buffer in this case
+ * too.
+ */
+
PNG_EXPORT(237, int, png_image_finish_read, (png_imagep image,
png_colorp background, void *buffer, png_int_32 row_stride));
/* Finish reading the image into the supplied buffer and clean up the
* png_image structure.
*
- * row_stride is the step, in png_byte or png_uint_16 units as appropriate,
+ * row_stride is the step, in byte or 2-byte units as appropriate,
* between adjacent rows. A positive stride indicates that the top-most row
* is first in the buffer - the normal top-down arrangement. A negative
* stride indicates that the bottom-most row is first in the buffer.
@@ -2859,6 +2974,10 @@
* onto the buffer. The value is an sRGB color to use for the background,
* for grayscale output the green channel is used.
*
+ * If png_image_read_colormap has been called the value of background must be
+ * the same as that passed to the colormap call or the resultant image pixels
+ * are implementation defined and may vary between libpng minor releases.
+ *
* For linear output removing the alpha channel is always done by compositing
* on black.
*/
@@ -2876,6 +2995,7 @@
* be written:
*
* opaque: must be initialized to NULL
+ * colormap: must be initialized to NULL
* width: image width in pixels
* height: image height in rows
* format: the format of the data you wish to write
@@ -2883,6 +3003,14 @@
* PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB
* values do not correspond to the colors in sRGB.
*/
+PNG_EXPORT(243, int, png_image_write_colormap, (png_imagep image,
+ png_const_bytep colormap));
+ /* Optionally write a color-mapped image. 'format' must be set to the format
+ * of the data in the color-map and must not be changed after the call. The
+ * colormap *pointer* is retained, the color-map data itself is not copied;
+ * the data must not be freed until after the called to png_image_write_*
+ */
+
PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image,
const char *file, int convert_to_8bit, const void *buffer,
png_int_32 row_stride));
@@ -2892,17 +3020,20 @@
int convert_to_8_bit, const void *buffer, png_int_32 row_stride));
/* Write the image to the given (FILE*). */
-/* With all write APIs if image is in one of the linear formats with
- * (png_uint_16) data then setting convert_to_8_bit will cause the output to be
- * a (png_byte) PNG gamma encoded according to the sRGB specification, otherwise
- * a 16-bit linear encoded PNG file is written.
+/* With all write APIs if image is in one of the linear formats with 16-bit data
+ * then setting convert_to_8_bit will cause the output to be an 8-bit PNG gamma
+ * encoded according to the sRGB specification, otherwise a 16-bit linear
+ * encoded PNG file is written.
+ *
+ * With color-mapped data png_image_write_colormap must be called. The palette
+ * may contain linear (16-bit) entries, these will be converted to sRGB values
+ * regardless of the setting of convert_to_8_bit.
*
* With all APIs row_stride is handled as in the read APIs - it is the spacing
- * from one row to the next in component sized units (float) and if negative
- * indicates a bottom-up row layout in the buffer.
+ * from one row to the next in component sized units (1 or 2 bytes) and if
+ * negative indicates a bottom-up row layout in the buffer.
*
- * Note that the write API does not support interlacing, sub-8-bit pixels,
- * and indexed (paletted) images.
+ * Note that the write API does not support interlacing or sub-8-bit pixels.
*/
#endif /* PNG_SIMPLIFIED_WRITE_SUPPORTED */
/*******************************************************************************
@@ -2918,7 +3049,7 @@
* scripts/symbols.def as well.
*/
#ifdef PNG_EXPORT_LAST_ORDINAL
- PNG_EXPORT_LAST_ORDINAL(241);
+ PNG_EXPORT_LAST_ORDINAL(243);
#endif
#ifdef __cplusplus
diff --git a/pngerror.c b/pngerror.c
index ed75c2f..f9861f6 100644
--- a/pngerror.c
+++ b/pngerror.c
@@ -789,7 +789,7 @@
if (image != NULL)
{
png_safecat(image->message, sizeof image->message, 0, error_message);
- image->warning_or_error = 1;
+ image->warning_or_error |= PNG_IMAGE_ERROR;
/* Retrieve the jmp_buf from within the png_control, making this work for
* C++ compilation too is pretty tricky: C++ wants a pointer to the first
@@ -821,7 +821,7 @@
if (image->warning_or_error == 0)
{
png_safecat(image->message, sizeof image->message, 0, warning_message);
- image->warning_or_error = 2;
+ image->warning_or_error |= PNG_IMAGE_WARNING;
}
}
#endif
diff --git a/pngread.c b/pngread.c
index b5e61e2..d1e8bef 100644
--- a/pngread.c
+++ b/pngread.c
@@ -1243,7 +1243,14 @@
png_uint_32 format = png_image_format(png_ptr, info_ptr);
image->format = format;
- image->flags = 0;
+
+ /* If the image is currently color mapped set the color map *flag* (but
+ * not the format, which is only set on demand.)
+ */
+ if (png_ptr->color_type & PNG_COLOR_MASK_PALETTE)
+ image->flags = PNG_IMAGE_FLAG_COLORMAP;
+ else
+ image->flags = 0;
/* Now try to work out whether the color data does not match sRGB. */
if ((format & PNG_FORMAT_FLAG_COLOR) != 0 &&
@@ -1273,8 +1280,7 @@
else if (info_ptr->valid & PNG_INFO_iCCP)
{
# if 0
- /* TODO: IMPLEMENT THIS! Remember to remove iCCP from
- the chunks_to_ignore list */
+ /* TODO: IMPLEMENT THIS! */
/* Here if we just have an iCCP chunk. */
if (!png_iCCP_is_sRGB(png_ptr, info_ptr))
# endif
@@ -1408,6 +1414,27 @@
return 0;
}
+int PNGAPI
+png_image_read_colormap(png_imagep image, png_bytep colormap,
+ png_colorp background)
+{
+ if (image != NULL)
+ {
+ if (colormap != NULL)
+ {
+ /* TODO: NYI: IMPLEMENT ME */
+ return png_image_error(image, "png_image_read_colormap: NYI");
+ }
+
+ else
+ return png_image_error(image,
+ "png_image_read_colormap: invalid argument");
+ }
+
+ PNG_UNUSED(background)
+ return 0;
+}
+
/* Arguments to png_image_finish_read: */
typedef struct
{
diff --git a/pngwrite.c b/pngwrite.c
index 9fa5ae0..1edac03 100644
--- a/pngwrite.c
+++ b/pngwrite.c
@@ -1561,6 +1561,32 @@
return png_image_error(image, "png_image_read: out of memory");
}
+int PNGAPI
+png_image_write_colormap(png_imagep image, png_const_bytep colormap)
+{
+ if (image != NULL)
+ {
+ if (colormap != NULL)
+ {
+ if ((image->format & PNG_FORMAT_FLAG_COLORMAP) == 0)
+ {
+ image->colormap = colormap; /* alias, caller must preserve */
+ image->format |= PNG_FORMAT_FLAG_COLORMAP;
+ }
+
+ else
+ return png_image_error(image,
+ "png_image_write_colormap: colormap already set");
+ }
+
+ else
+ return png_image_error(image,
+ "png_image_write_colormap: invalid argument");
+ }
+
+ return 0;
+}
+
/* Arguments to png_image_write_main: */
typedef struct
{
@@ -1839,11 +1865,15 @@
display->row_stride = PNG_IMAGE_ROW_STRIDE(*image);
/* Set the required transforms then write the rows in the correct order. */
- png_set_IHDR(png_ptr, info_ptr, image->width, image->height,
- write_16bit ? 16 : 8,
- ((format & PNG_FORMAT_FLAG_COLOR) ? PNG_COLOR_MASK_COLOR : 0) +
- ((format & PNG_FORMAT_FLAG_ALPHA) ? PNG_COLOR_MASK_ALPHA : 0),
- PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+ if (format & PNG_FORMAT_FLAG_COLORMAP)
+ return png_image_error(image, "png_image_write: colormap NYI");
+
+ else
+ png_set_IHDR(png_ptr, info_ptr, image->width, image->height,
+ write_16bit ? 16 : 8,
+ ((format & PNG_FORMAT_FLAG_COLOR) ? PNG_COLOR_MASK_COLOR : 0) +
+ ((format & PNG_FORMAT_FLAG_ALPHA) ? PNG_COLOR_MASK_ALPHA : 0),
+ PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
/* Counter-intuitively the data transformations must be called *after*
* png_write_info, not before as in the read code, but the 'set' functions
