Imported from libpng-1.0.4-pre1.tar
diff --git a/libpng.3 b/libpng.3
index f970736..47091d4 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,416 +1,610 @@
-.TH LIBPNG 3 "January 14, 1999"
+.TH LIBPNG 3 "September 17, 1999"
.SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.0.3 - January 14, 1999
+libpng \- Portable Network Graphics (PNG) Reference Library 1.0.4 - September 17, 1999
.SH SYNOPSIS
+\fI\fB
-#include <png.h>
+\fB#include <png.h>\fP
-int png_check_sig (png_bytep sig, int num);
+\fI\fB
-void png_chunk_error (png_structp png_ptr, png_const_charp
-error);
+\fBint png_check_sig (png_bytep \fP\fIsig\fP\fB, int \fInum\fP\fB);\fP
-void png_chunk_warning (png_structp png_ptr, png_const_charp
-message);
+\fI\fB
-void png_convert_from_struct_tm (png_timep ptime, struct tm FAR
-* ttime);
+\fBvoid png_chunk_error (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fIerror\fP\fB);\fP
-void png_convert_from_time_t (png_timep ptime, time_t ttime);
+\fI\fB
-png_charp png_convert_to_rfc1123 (png_structp png_ptr,
-png_timep ptime);
+\fBvoid png_chunk_warning (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fImessage\fP\fB);\fP
-png_infop png_create_info_struct (png_structp png_ptr);
+\fI\fB
-png_structp png_create_read_struct (png_const_charp
-user_png_ver, voidp error_ptr, png_error_ptr error_fn,
-png_error_ptr warn_fn);
+\fBvoid png_convert_from_struct_tm (png_timep \fP\fIptime\fP\fB, struct tm FAR * \fIttime\fP\fB);\fP
-png_structp png_create_read_struct_2(png_const_charp user_png_ver,
-png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr
-warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn,
-png_free_ptr free_fn)
+\fI\fB
-png_structp png_create_write_struct (png_const_charp
-user_png_ver, voidp error_ptr, png_error_ptr error_fn,
-png_error_ptr warn_fn);
+\fBvoid png_convert_from_time_t (png_timep \fP\fIptime\fP\fB, time_t \fIttime\fP\fB);\fP
-png_structp png_create_write_struct_2(png_const_charp
-user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
-png_error_ptr warn_fn, png_voidp mem_ptr,
-png_malloc_ptr malloc_fn, png_free_ptr free_fn)
+\fI\fB
-int png_debug(int level, png_const_charp message)
+\fBpng_charp png_convert_to_rfc1123 (png_structp \fP\fIpng_ptr\fP\fB, png_timep \fIptime\fP\fB);\fP
-int png_debug1(int level, png_const_charp message, p1)
+\fI\fB
-int png_debug2(int level, png_const_charp message, p1, p2)
+\fBpng_infop png_create_info_struct (png_structp \fIpng_ptr\fP\fB);\fP
-void png_destroy_info_struct (png_structp png_ptr, png_infopp
-info_ptr_ptr);
+\fI\fB
-void png_destroy_read_struct (png_structpp png_ptr_ptr,
-png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr);
+\fBpng_structp png_create_read_struct (png_const_charp \fP\fIuser_png_ver\fP\fB, voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fIwarn_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_structp png_create_read_struct_2(png_const_charp \fP\fIuser_png_ver\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fP\fIwarn_fn\fP\fB, png_voidp \fP\fImem_ptr\fP\fB, png_malloc_ptr \fP\fImalloc_fn\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_structp png_create_write_struct (png_const_charp \fP\fIuser_png_ver\fP\fB, voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fIwarn_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_structp png_create_write_struct_2(png_const_charp \fP\fIuser_png_ver\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fP\fIwarn_fn\fP\fB, png_voidp \fP\fImem_ptr\fP\fB, png_malloc_ptr \fP\fImalloc_fn\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_debug(int \fP\fIlevel\fP\fB, png_const_charp \fImessage\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_debug1(int \fP\fIlevel\fP\fB, png_const_charp \fP\fImessage\fP\fB, \fIp1\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_debug2(int \fP\fIlevel\fP\fB, png_const_charp \fP\fImessage\fP\fB, \fP\fIp1\fP\fB, \fIp2\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_destroy_info_struct (png_structp \fP\fIpng_ptr\fP\fB, png_infopp \fIinfo_ptr_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_destroy_read_struct (png_structpp \fP\fIpng_ptr_ptr\fP\fB, png_infopp \fP\fIinfo_ptr_ptr\fP\fB, png_infopp \fIend_info_ptr_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_destroy_write_struct (png_structpp \fP\fIpng_ptr_ptr\fP\fB, png_infopp \fIinfo_ptr_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_error (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fIerror\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_free (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fIptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_free_default(png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fIptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_bit_depth (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_bKGD (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_color_16p \fI*background\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_channels (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fP\fI*white_x\fP\fB, double \fP\fI*white_y\fP\fB, double \fP\fI*red_x\fP\fB, double \fP\fI*red_y\fP\fB, double \fP\fI*green_x\fP\fB, double \fP\fI*green_y\fP\fB, double \fP\fI*blue_x\fP\fB, double \fI*blue_y\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_color_type (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_compression_type (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_copyright (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_error_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_filter_type (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_gAMA (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fI*file_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_header_version (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_16p \fI*hist\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fI*width\fP\fB, png_uint_32 \fP\fI*height\fP\fB, int \fP\fI*bit_depth\fP\fB, int \fP\fI*color_type\fP\fB, int \fP\fI*interlace_type\fP\fB, int \fP\fI*compression_type\fP\fB, int \fI*filter_type\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_image_height (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_image_width (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_interlace_type (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_io_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_mem_ptr(png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_oFFs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fI*offset_x\fP\fB, png_uint_32 \fP\fI*offset_y\fP\fB, int \fI*unit_type\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_pCAL (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_charp \fP\fI*purpose\fP\fB, png_int_32 \fP\fI*X0\fP\fB, png_int_32 \fP\fI*X1\fP\fB, int \fP\fI*type\fP\fB, int \fP\fI*nparams\fP\fB, png_charp \fP\fI*units\fP\fB, png_charpp \fI*params\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_pHYs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fI*res_x\fP\fB, png_uint_32 \fP\fI*res_y\fP\fB, int \fI*unit_type\fP\fB);\fP
+
+\fI\fB
+
+\fBfloat png_get_pixel_aspect_ratio (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_pixels_per_meter (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_progressive_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_colorp \fP\fI*palette\fP\fB, int \fI*num_palette\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_byte png_get_rgb_to_gray_status (png_structp \fIpng_ptr)
+
+\fBpng_uint_32 png_get_rowbytes (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_sBIT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_color_8p \fI*sig_bit\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_bytep png_get_signature (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_sRGB (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fI*intent\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_text (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_textp \fP\fI*text_ptr\fP\fB, int \fI*num_text\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_tIME (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_timep \fI*mod_time\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_tRNS (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_bytep \fP\fI*trans\fP\fB, int \fP\fI*num_trans\fP\fB, png_color_16p \fI*trans_values\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_get_user_transform_ptr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_valid (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIflag\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_x_offset_microns (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_x_offset_pixels (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_x_pixels_per_meter (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_y_offset_microns (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_y_offset_pixels (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_y_pixels_per_meter (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_info_init (png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_init_io (png_structp \fP\fIpng_ptr\fP\fB, FILE \fI*fp\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_malloc (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_malloc_default(png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBvoidp png_memcpy (png_voidp \fP\fIs1\fP\fB, png_voidp \fP\fIs2\fP\fB, png_size_t \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_memcpy_check (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIs1\fP\fB, png_voidp \fP\fIs2\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBvoidp png_memset (png_voidp \fP\fIs1\fP\fB, int \fP\fIvalue\fP\fB, png_size_t \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_memset_check (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIs1\fP\fB, int \fP\fIvalue\fP\fB, png_uint_32 \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_permit_empty_plte (png_structp \fP\fIpng_ptr\fP\fB, int \fIempty_plte_permitted\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_process_data (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_bytep \fP\fIbuffer\fP\fB, png_size_t \fIbuffer_size\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_progressive_combine_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIold_row\fP\fB, png_bytep \fInew_row\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_destroy (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_infop \fIend_info_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_end (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_image (png_structp \fP\fIpng_ptr\fP\fB, png_bytepp \fIimage\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIrow\fP\fB, png_bytep \fIdisplay_row\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_rows (png_structp \fP\fIpng_ptr\fP\fB, png_bytepp \fP\fIrow\fP\fB, png_bytepp \fP\fIdisplay_row\fP\fB, png_uint_32 \fInum_rows\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_update_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_background (png_structp \fP\fIpng_ptr\fP\fB, png_color_16p \fP\fIbackground_color\fP\fB, int \fP\fIbackground_gamma_code\fP\fB, int \fP\fIneed_expand\fP\fB, double \fIbackground_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_bgr (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_bKGD (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_color_16p \fIbackground\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fP\fIwhite_x\fP\fB, double \fP\fIwhite_y\fP\fB, double \fP\fIred_x\fP\fB, double \fP\fIred_y\fP\fB, double \fP\fIgreen_x\fP\fB, double \fP\fIgreen_y\fP\fB, double \fP\fIblue_x\fP\fB, double \fIblue_y\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_level (png_structp \fP\fIpng_ptr\fP\fB, int \fIlevel\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_mem_level (png_structp \fP\fIpng_ptr\fP\fB, int \fImem_level\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_set_compression_method (png_structp \fP\fIpng_ptr\fP\fB, int \fImethod\fP\fB);\fP
+
+\fI\fB
-void png_destroy_write_struct (png_structpp png_ptr_ptr,
-png_infopp info_ptr_ptr);
+\fBvoid png_set_compression_strategy (png_structp \fP\fIpng_ptr\fP\fB, int \fIstrategy\fP\fB);\fP
-void png_error (png_structp png_ptr, png_const_charp error);
+\fI\fB
-void png_free (png_structp png_ptr, png_voidp ptr);
+\fBvoid png_set_compression_window_bits (png_structp \fP\fIpng_ptr\fP\fB, int \fIwindow_bits\fP\fB);\fP
-void png_free_default(png_structp png_ptr, png_voidp ptr)
+\fI\fB
-png_byte png_get_bit_depth (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_set_crc_action (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fIcrit_action\fP\fB, int \fIancil_action\fP\fB);\fP
-png_uint_32 png_get_bKGD (png_structp png_ptr, png_infop
-info_ptr, png_color_16p *background);
+\fI\fB
-png_byte png_get_channels (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_set_dither (png_structp \fP\fIpng_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, int \fP\fInum_palette\fP\fB, int \fP\fImaximum_colors\fP\fB, png_uint_16p \fP\fIhistogram\fP\fB, int \fIfull_dither\fP\fB);\fP
-png_uint_32 png_get_cHRM (png_structp png_ptr, png_infop
-info_ptr, double *white_x, double *white_y, double *red_x,
-double *red_y, double *green_x, double *green_y, double
-*blue_x, double *blue_y);
+\fI\fB
-png_byte png_get_color_type (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_set_error_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIerror_ptr\fP\fB, png_error_ptr \fP\fIerror_fn\fP\fB, png_error_ptr \fIwarning_fn\fP\fB);\fP
-png_byte png_get_compression_type (png_structp png_ptr,
-png_infop info_ptr);
+\fI\fB
-png_byte png_get_copyright (png_structp png_ptr);
+\fBvoid png_set_expand (png_structp \fIpng_ptr\fP\fB);\fP
-png_voidp png_get_error_ptr (png_structp png_ptr);
+\fI\fB
-png_byte png_get_filter_type (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_set_filler (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIfiller\fP\fB, int \fIflags\fP\fB);\fP
-png_uint_32 png_get_gAMA (png_structp png_ptr, png_infop
-info_ptr, double *file_gamma);
+\fI\fB
-png_byte png_get_header_version (png_structp png_ptr);
+\fBvoid png_set_filter (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fImethod\fP\fB, int \fIfilters\fP\fB);\fP
-png_uint_32 png_get_hIST (png_structp png_ptr, png_infop
-info_ptr, png_uint_16p *hist);
+\fI\fB
-png_uint_32 png_get_IHDR (png_structp png_ptr, png_infop
-info_ptr, png_uint_32 *width, png_uint_32 *height, int
-*bit_depth, int *color_type, int *interlace_type, int
-*compression_type, int *filter_type);
+\fBvoid png_set_filter_heuristics (png_structp \fP\fIpng_ptr\fP\fB, int \fP\fIheuristic_method\fP\fB, int \fP\fInum_weights\fP\fB, png_doublep \fP\fIfilter_weights\fP\fB, png_doublep \fIfilter_costs\fP\fB);\fP
-png_uint_32 png_get_image_height (png_structp png_ptr,
-png_infop info_ptr);
+\fI\fB
-png_uint_32 png_get_image_width (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_set_flush (png_structp \fP\fIpng_ptr\fP\fB, int \fInrows\fP\fB);\fP
-png_byte png_get_interlace_type (png_structp png_ptr, png_infop
-info_ptr);
+\fI\fB
-png_voidp png_get_io_ptr (png_structp png_ptr);
+\fBvoid png_set_gamma (png_structp \fP\fIpng_ptr\fP\fB, double \fP\fIscreen_gamma\fP\fB, double \fIdefault_file_gamma\fP\fB);\fP
-png_voidp png_get_mem_ptr(png_structp png_ptr)
+\fI\fB
-png_uint_32 png_get_oFFs (png_structp png_ptr, png_infop
-info_ptr, png_uint_32 *offset_x, png_uint_32 *offset_y, int
-*unit_type);
+\fBvoid png_set_gAMA (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fIfile_gamma\fP\fB);\fP
-png_uint_32 png_get_pCAL (png_structp png_ptr, png_infop
-info_ptr, png_charp *purpose, png_int_32 *X0, png_int_32 *X1,
-int *type, int *nparams, png_charp *units, png_charpp *params);
+\fI\fB
-png_uint_32 png_get_pHYs (png_structp png_ptr, png_infop
-info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, int
-*unit_type);
+\fBvoid png_set_gray_1_2_4_to_8(png_structp \fIpng_ptr\fP\fB);\fP
-float png_get_pixel_aspect_ratio (png_structp png_ptr,
-png_infop info_ptr);
+\fI\fB
-png_uint_32 png_get_pixels_per_meter (png_structp png_ptr,
-png_infop info_ptr);
+\fBvoid png_set_gray_to_rgb (png_structp \fIpng_ptr\fP\fB);\fP
-png_voidp png_get_progressive_ptr (png_structp png_ptr);
+\fI\fB
-png_uint_32 png_get_PLTE (png_structp png_ptr, png_infop
-info_ptr, png_colorp *palette, int *num_palette);
+\fBvoid png_set_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_16p \fIhist\fP\fB);\fP
-png_byte png_get_rgb_to_gray_status (png_structp png_ptr)
+\fI\fB
-png_uint_32 png_get_rowbytes (png_structp png_ptr, png_infop
-info_ptr);
+\fBint png_set_interlace_handling (png_structp \fIpng_ptr\fP\fB);\fP
-png_uint_32 png_get_sBIT (png_structp png_ptr, png_infop
-info_ptr, png_color_8p *sig_bit);
+\fI\fB
-png_bytep png_get_signature (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_set_invert_alpha (png_structp \fIpng_ptr\fP\fB);\fP
-png_uint_32 png_get_sRGB (png_structp png_ptr, png_infop
-info_ptr, int *intent);
+\fI\fB
-png_uint_32 png_get_text (png_structp png_ptr, png_infop
-info_ptr, png_textp *text_ptr, int *num_text);
+\fBvoid png_set_invert_mono (png_structp \fIpng_ptr\fP\fB);\fP
-png_uint_32 png_get_tIME (png_structp png_ptr, png_infop
-info_ptr, png_timep *mod_time);
+\fI\fB
-png_uint_32 png_get_tRNS (png_structp png_ptr, png_infop
-info_ptr, png_bytep *trans, int *num_trans, png_color_16p
-*trans_values);
+\fBvoid png_set_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fIwidth\fP\fB, png_uint_32 \fP\fIheight\fP\fB, int \fP\fIbit_depth\fP\fB, int \fP\fIcolor_type\fP\fB, int \fP\fIinterlace_type\fP\fB, int \fP\fIcompression_type\fP\fB, int \fIfilter_type\fP\fB);\fP
-png_uint_32 png_get_valid (png_structp png_ptr, png_infop
-info_ptr, png_uint_32 flag);
+\fI\fB
-png_uint_32 png_get_x_offset_microns (png_structp png_ptr,
-png_infop info_ptr);
+\fBvoid png_set_mem_fn(png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fImem_ptr\fP\fB, png_malloc_ptr \fP\fImalloc_fn\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
-png_uint_32 png_get_x_offset_pixels (png_structp png_ptr,
-png_infop info_ptr);
+\fI\fB
-png_uint_32 png_get_x_pixels_per_meter (png_structp png_ptr,
-png_infop info_ptr);
+\fBvoid png_set_oFFs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fIoffset_x\fP\fB, png_uint_32 \fP\fIoffset_y\fP\fB, int \fIunit_type\fP\fB);\fP
-png_uint_32 png_get_y_offset_microns (png_structp png_ptr,
-png_infop info_ptr);
+\fI\fB
-png_uint_32 png_get_y_offset_pixels (png_structp png_ptr,
-png_infop info_ptr);
+\fBvoid png_set_packing (png_structp \fIpng_ptr\fP\fB);\fP
-png_uint_32 png_get_y_pixels_per_meter (png_structp png_ptr,
-png_infop info_ptr);
+\fI\fB
-void png_info_init (png_infop info_ptr);
+\fBvoid png_set_packswap (png_structp \fIpng_ptr\fP\fB);\fP
-void png_init_io (png_structp png_ptr, FILE *fp);
+\fI\fB
-png_voidp png_malloc (png_structp png_ptr, png_uint_32 size);
+\fBvoid png_set_palette_to_rgb(png_structp \fIpng_ptr\fP\fB);\fP
-png_voidp png_malloc_default(png_structp png_ptr,
-png_uint_32 size)
+\fI\fB
-voidp png_memcpy (png_voidp s1, png_voidp s2, png_size_t size);
+\fBvoid png_set_pCAL (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_charp \fP\fIpurpose\fP\fB, png_int_32 \fP\fIX0\fP\fB, png_int_32 \fP\fIX1\fP\fB, int \fP\fItype\fP\fB, int \fP\fInparams\fP\fB, png_charp \fP\fIunits\fP\fB, png_charpp \fIparams\fP\fB);\fP
-png_voidp png_memcpy_check (png_structp png_ptr, png_voidp s1,
-png_voidp s2, png_uint_32 size);
+\fI\fB
-voidp png_memset (png_voidp s1, int value, png_size_t size);
+\fBvoid png_set_pHYs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fP\fIres_x\fP\fB, png_uint_32 \fP\fIres_y\fP\fB, int \fIunit_type\fP\fB);\fP
-png_voidp png_memset_check (png_structp png_ptr, png_voidp
-s1, int value, png_uint_32 size);
+\fI\fB
-void png_process_data (png_structp png_ptr, png_infop info_ptr,
-png_bytep buffer, png_size_t buffer_size);
+\fBvoid png_set_progressive_read_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIprogressive_ptr\fP\fB, png_progressive_info_ptr \fP\fIinfo_fn\fP\fB, png_progressive_row_ptr \fP\fIrow_fn\fP\fB, png_progressive_end_ptr \fIend_fn\fP\fB);\fP
-void png_progressive_combine_row (png_structp png_ptr,
-png_bytep old_row, png_bytep new_row);
+\fI\fB
-void png_read_destroy (png_structp png_ptr, png_infop info_ptr,
-png_infop end_info_ptr);
+\fBvoid png_set_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, int \fInum_palette\fP\fB);\fP
-void png_read_end (png_structp png_ptr, png_infop info_ptr);
+\fI\fB
-void png_read_image (png_structp png_ptr, png_bytepp image);
+\fBvoid png_set_read_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIio_ptr\fP\fB, png_rw_ptr \fIread_data_fn\fP\fB);\fP
-void png_read_info (png_structp png_ptr, png_infop info_ptr);
+\fI\fB
-void png_read_row (png_structp png_ptr, png_bytep row,
-png_bytep display_row);
+\fBvoid png_set_read_status_fn (png_structp \fP\fIpng_ptr\fP\fB, png_read_status_ptr \fIread_row_fn\fP\fB);\fP
-void png_read_rows (png_structp png_ptr, png_bytepp row,
-png_bytepp display_row, png_uint_32 num_rows);
+\fI\fB
-void png_read_update_info (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_set_read_user_transform_fn (png_structp \fP\fIpng_ptr\fP\fB, png_user_transform_ptr \fIread_user_transform_fn\fP\fB);\fP
-void png_set_background (png_structp png_ptr, png_color_16p
-background_color, int background_gamma_code, int need_expand,
-double background_gamma);
+\fI\fB
-void png_set_bgr (png_structp png_ptr);
+\fBvoid png_set_rgb_to_gray (png_structp \fP\fIpng_ptr\fP\fB, int \fIerror_action\fP\fB);\fP
-void png_set_bKGD (png_structp png_ptr, png_infop info_ptr,
-png_color_16p background);
+\fI\fB
-void png_set_cHRM (png_structp png_ptr, png_infop info_ptr,
-double white_x, double white_y, double red_x, double red_y,
-double green_x, double green_y, double blue_x, double blue_y);
+\fBvoid png_set_sBIT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_color_8p \fIsig_bit\fP\fB);\fP
-void png_set_compression_level (png_structp png_ptr, int
-level);
+\fI\fB
-void png_set_compression_mem_level (png_structp png_ptr, int
-mem_level);
+\fBvoid png_set_shift (png_structp \fP\fIpng_ptr\fP\fB, png_color_8p \fItrue_bits\fP\fB);\fP
-void png_set_compression_method (png_structp png_ptr, int
-method);
+\fI\fB
-void png_set_compression_strategy (png_structp png_ptr, int
-strategy);
+\fBvoid png_set_sig_bytes (png_structp \fP\fIpng_ptr\fP\fB, int \fInum_bytes\fP\fB);\fP
-void png_set_compression_window_bits (png_structp png_ptr, int
-window_bits);
+\fI\fB
-void png_set_crc_action (png_structp png_ptr, int crit_action,
-int ancil_action);
+\fBvoid png_set_sRGB (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fIintent\fP\fB);\fP
-void png_set_dither (png_structp png_ptr, png_colorp palette,
-int num_palette, int maximum_colors, png_uint_16p histogram,
-int full_dither);
+\fI\fB
-void png_set_error_fn (png_structp png_ptr, png_voidp
-error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn);
+\fBvoid png_set_sRGB_gAMA_and_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, int \fIintent\fP\fB);\fP
-void png_set_expand (png_structp png_ptr);
+\fI\fB
-void png_set_filler (png_structp png_ptr, png_uint_32 filler,
-int flags);
+\fBvoid png_set_strip_16 (png_structp \fIpng_ptr\fP\fB);\fP
-void png_set_filter (png_structp png_ptr, int method, int
-filters);
+\fI\fB
-void png_set_filter_heuristics (png_structp png_ptr, int
-heuristic_method, int num_weights, png_doublep filter_weights,
-png_doublep filter_costs);
+\fBvoid png_set_strip_alpha (png_structp \fIpng_ptr\fP\fB);\fP
-void png_set_flush (png_structp png_ptr, int nrows);
+\fI\fB
-void png_set_gamma (png_structp png_ptr, double screen_gamma,
-double default_file_gamma);
+\fBvoid png_set_swap (png_structp \fIpng_ptr\fP\fB);\fP
-void png_set_gAMA (png_structp png_ptr, png_infop info_ptr,
-double file_gamma);
+\fI\fB
-void png_set_gray_to_rgb (png_structp png_ptr);
+\fBvoid png_set_swap_alpha (png_structp \fIpng_ptr\fP\fB);\fP
-void png_set_hIST (png_structp png_ptr, png_infop info_ptr,
-png_uint_16p hist);
+\fI\fB
-int png_set_interlace_handling (png_structp png_ptr);
+\fBvoid png_set_text (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_textp \fP\fItext_ptr\fP\fB, int \fInum_text\fP\fB);\fP
-void png_set_invert_alpha (png_structp png_ptr);
+\fI\fB
-void png_set_invert_mono (png_structp png_ptr);
+\fBvoid png_set_tIME (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_timep \fImod_time\fP\fB);\fP
-void png_set_IHDR (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 width, png_uint_32 height, int bit_depth, int
-color_type, int interlace_type, int compression_type, int
-filter_type);
+\fI\fB
-void png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr,
-png_malloc_ptr malloc_fn, png_free_ptr free_fn)
+\fBvoid png_set_tRNS (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_bytep \fP\fItrans\fP\fB, int \fP\fInum_trans\fP\fB, png_color_16p \fItrans_values\fP\fB);\fP
-void png_set_oFFs (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 offset_x, png_uint_32 offset_y, int unit_type);
+\fI\fB
-void png_set_packing (png_structp png_ptr);
+\fBvoid png_set_tRNS_to_alpha(png_structp \fIpng_ptr\fP\fB);\fP
-void png_set_packswap (png_structp png_ptr);
+\fI\fB
-void png_set_pCAL (png_structp png_ptr, png_infop info_ptr,
-png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int
-nparams, png_charp units, png_charpp params);
+\fBvoid png_set_user_transform_info (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIuser_transform_ptr\fP\fB, int \fP\fIuser_transform_depth\fP\fB, int \fIuser_transform_channels\fP\fB);\fP
-void png_set_pHYs (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 res_x, png_uint_32 res_y, int unit_type);
+\fI\fB
-void png_set_progressive_read_fn (png_structp png_ptr,
-png_voidp progressive_ptr, png_progressive_info_ptr info_fn,
-png_progressive_row_ptr row_fn, png_progressive_end_ptr
-end_fn);
+\fBvoid png_set_write_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIio_ptr\fP\fB, png_rw_ptr \fP\fIwrite_data_fn\fP\fB, png_flush_ptr \fIoutput_flush_fn\fP\fB);\fP
-void png_set_PLTE (png_structp png_ptr, png_infop info_ptr,
-png_colorp palette, int num_palette);
+\fI\fB
-void png_set_read_fn (png_structp png_ptr, png_voidp io_ptr,
-png_rw_ptr read_data_fn);
+\fBvoid png_set_write_status_fn (png_structp \fP\fIpng_ptr\fP\fB, png_write_status_ptr \fIwrite_row_fn\fP\fB);\fP
-void png_set_read_status_fn (png_structp png_ptr, png_read_status_ptr
-read_row_fn);
+\fI\fB
-void png_set_read_user_transform_fn (png_structp png_ptr,
-png_user_transform_ptr read_user_transform_fn);
+\fBvoid png_set_write_user_transform_fn (png_structp \fP\fIpng_ptr\fP\fB, png_user_transform_ptr \fIwrite_user_transform_fn\fP\fB);\fP
-void png_set_rgb_to_gray (png_structp png_ptr, int error_action);
+\fI\fB
-void png_set_sBIT (png_structp png_ptr, png_infop info_ptr,
-png_color_8p sig_bit);
+\fBint png_sig_cmp (png_bytep \fP\fIsig\fP\fB, png_size_t \fP\fIstart\fP\fB, png_size_t \fInum_to_check\fP\fB);\fP
-void png_set_shift (png_structp png_ptr, png_color_8p
-true_bits);
+\fI\fB
-void png_set_sig_bytes (png_structp png_ptr, int num_bytes);
+\fBvoid png_start_read_image (png_structp \fIpng_ptr\fP\fB);\fP
-void png_set_sRGB (png_structp png_ptr, png_infop info_ptr, int
-intent);
+\fI\fB
-void png_set_sRGB_gAMA_and_cHRM (png_structp png_ptr, png_infop
-info_ptr, int intent);
+\fBvoid png_warning (png_structp \fP\fIpng_ptr\fP\fB, png_const_charp \fImessage\fP\fB);\fP
-void png_set_strip_16 (png_structp png_ptr);
+\fI\fB
-void png_set_strip_alpha (png_structp png_ptr);
+\fBvoid png_write_chunk (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIchunk_name\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
-void png_set_swap (png_structp png_ptr);
+\fI\fB
-void png_set_swap_alpha (png_structp png_ptr);
+\fBvoid png_write_chunk_data (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
-void png_set_text (png_structp png_ptr, png_infop info_ptr,
-png_textp text_ptr, int num_text);
+\fI\fB
-void png_set_tIME (png_structp png_ptr, png_infop info_ptr,
-png_timep mod_time);
+\fBvoid png_write_chunk_end (png_structp \fIpng_ptr\fP\fB);\fP
-void png_set_tRNS (png_structp png_ptr, png_infop info_ptr,
-png_bytep trans, int num_trans, png_color_16p trans_values);
+\fI\fB
-void png_set_write_fn (png_structp png_ptr, png_voidp io_ptr,
-png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn);
+\fBvoid png_write_chunk_start (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIchunk_name\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
-void png_set_write_status_fn (png_structp png_ptr, png_write_status_ptr
-write_row_fn);
+\fI\fB
-void png_set_write_user_transform_fn (png_structp png_ptr,
-png_user_transform_ptr write_user_transform_fn);
+\fBvoid png_write_destroy (png_structp \fIpng_ptr\fP\fB);\fP
-int png_sig_cmp (png_bytep sig, png_size_t start, png_size_t
-num_to_check);
+\fI\fB
-void png_start_read_image (png_structp png_ptr);
+\fBvoid png_write_destroy_info (png_infop \fIinfo_ptr\fP\fB);\fP
-void png_warning (png_structp png_ptr, png_const_charp
-message);
+\fI\fB
-void png_write_chunk (png_structp png_ptr, png_bytep
-chunk_name, png_bytep data, png_size_t length);
+\fBvoid png_write_end (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
-void png_write_chunk_data (png_structp png_ptr, png_bytep data,
-png_size_t length);
+\fI\fB
-void png_write_chunk_end (png_structp png_ptr);
+\fBvoid png_write_flush (png_structp \fIpng_ptr\fP\fB);\fP
-void png_write_chunk_start (png_structp png_ptr, png_bytep
-chunk_name, png_uint_32 length);
+\fI\fB
-void png_write_destroy (png_structp png_ptr);
+\fBvoid png_write_image (png_structp \fP\fIpng_ptr\fP\fB, png_bytepp \fIimage\fP\fB);\fP
-void png_write_destroy_info (png_infop info_ptr);
+\fI\fB
-void png_write_end (png_structp png_ptr, png_infop info_ptr);
+\fBvoid png_write_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
-void png_write_flush (png_structp png_ptr);
+\fI\fB
-void png_write_image (png_structp png_ptr, png_bytepp image);
+\fBvoid png_write_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIrow\fP\fB);\fP
-void png_write_info (png_structp png_ptr, png_infop info_ptr);
+\fI\fB
-void png_write_row (png_structp png_ptr, png_bytep row);
+\fBvoid png_write_rows (png_structp \fP\fIpng_ptr\fP\fB, png_bytepp \fP\fIrow\fP\fB, png_uint_32 \fInum_rows\fP\fB);\fP
-void png_write_rows (png_structp png_ptr, png_bytepp row,
-png_uint_32 num_rows);
+\fI\fB
.SH DESCRIPTION
The
@@ -423,9 +617,9 @@
.SH LIBPNG.TXT
libpng.txt - A description on how to use and modify libpng
- libpng version 1.0.3 - January 14, 1999
+ libpng version 1.0.4 - September 17, 1999
Updated and distributed by Glenn Randers-Pehrson
- <randeg@alumni.rpi.edu>
+ <randeg@alum.rpi.edu>
Copyright (c) 1998, 1999 Glenn Randers-Pehrson
For conditions of distribution and use, see copyright
notice in png.h.
@@ -445,6 +639,7 @@
Copyright (c) 1995 Frank J. T. Wojcik
December 18, 1995 && January 20, 1996
+ *
.SH I. Introduction
This file describes how to use and modify the PNG reference library
@@ -458,11 +653,17 @@
Libpng was written as a companion to the PNG specification, as a way
of reducing the amount of time and effort it takes to support the PNG
-file format in application programs. The PNG specification is available
+file format in application programs.
+
+The PNG-1.2 specification is available at <http://www.cdrom.com/png>.
+
+The PNG-1.0 specification is available
as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/> and as a
W3C Recommendation <http://www.w3.org/TR/REC.png.html>. Some
additional chunks are described in the special-purpose public chunks
-documents at <ftp://ftp.uu.net/graphics/png/documents/>. Other information
+documents at <ftp://ftp.uu.net/graphics/png/documents/>.
+
+Other information
about PNG, and the latest version of libpng, can be found at the PNG home
page, <http://www.cdrom.com/pub/png/>.
@@ -684,6 +885,21 @@
See pngtest.c for a working example. Your function will be called
after all of the other transformations have been processed.
+You can also set up a pointer to a user structure for use by your
+callback function, and you can inform libpng that your transform
+function will change the number of channels or bit depth with the
+function
+
+ png_set_user_transform_info(png_ptr, user_ptr,
+ user_depth, user_channels);
+
+
+You can retrieve the pointer via the function
+png_get_user_transform_ptr(). For example:
+
+ voidp read_user_transform_ptr =
+ png_get_user_transform_ptr(png_ptr);
+
You are now ready to read all the file information up to the actual
image data. You do this with a call to png_read_info().
@@ -929,13 +1145,18 @@
viewing application that wishes to treat all images in the same way.
if (color_type == PNG_COLOR_TYPE_PALETTE &&
- bit_depth <= 8) png_set_expand(png_ptr);
+ bit_depth <= 8) png_set_palette_to_rgb(png_ptr);
if (color_type == PNG_COLOR_TYPE_GRAY &&
- bit_depth < 8) png_set_expand(png_ptr);
+ bit_depth < 8) png_set_gray_1_2_4_to_8(png_ptr);
if (png_get_valid(png_ptr, info_ptr,
- PNG_INFO_tRNS)) png_set_expand(png_ptr);
+ PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_ptr);
+
+These three functions are actually aliases for png_set_expand(), added
+in libpng version 1.0.4, with the function names expanded to improve code
+readability. In some future version they may actually do different
+things.
PNG can have files with 16 bits per channel. If you only can handle
8 bits per channel, this will strip the pixels down to 8 bit.
@@ -1022,7 +1243,7 @@
if (color_type == PNG_COLOR_TYPE_RGB ||
color_type == PNG_COLOR_TYPE_RGB_ALPHA)
png_set_rgb_to_gray(png_ptr, error_action,
- float red_weight, float green_weight);
+ double red_weight, double green_weight);
error_action = 1: silently do the conversion
error_action = 2: issue a warning if the original
@@ -1071,7 +1292,8 @@
The calculation is done in a linear colorspace, if the image gamma
is known.
-If you have a grayscale and you are using png_set_expand() to change to
+If you have a grayscale and you are using png_set_expand_depth() or
+png_set_expand() to change to
a higher bit-depth, you must either supply the background color as a gray
value at the original file bit-depth (need_expand = 1) or else supply the
background color as an RGB triplet at the final, expanded bit depth
@@ -1104,6 +1326,8 @@
a (viewing_gamma=1.25) environment. In a dim or brightly lit room, no
compensation other than the display_gamma is needed (viewing_gamma=1.0).
+ double gamma, screen_gamma;
+
if (/* We have a user-defined screen
gamma value */)
{
@@ -1114,7 +1338,7 @@
else if ((gamma_str = getenv("SCREEN_GAMMA"))
!= NULL)
{
- screen_gamma = atof(gamma_str);
+ screen_gamma = (double)atof(gamma_str);
}
/* If we don't have another value */
else
@@ -1254,7 +1478,7 @@
png_read_row(png_ptr, &row_pointers, NULL);
If the file is interlaced (info_ptr->interlace_type != 0), things get
-somewhat harder. The only current (PNG Specification version 1.0)
+somewhat harder. The only current (PNG Specification version 1.2)
interlacing type for PNG is (interlace_type == PNG_INTERLACE_ADAM7)
is a somewhat complicated 2D interlace scheme, known as Adam7, that
breaks down an image into seven smaller images of varying size, based
@@ -1617,7 +1841,7 @@
not calling this function at all, as it has been tuned to deliver a good
speed/compression ratio. The second parameter to png_set_filter() is
the filter method, for which the only valid value is '0' (as of the
-October 1996 PNG specification, version 1.0). The third parameter is a
+July 1999 PNG specification, version 1.2). The third parameter is a
flag that indicates which filter type(s) are to be tested for each
scanline. See the Compression Library for details on the specific filter
types.
@@ -1649,7 +1873,7 @@
You now need to fill in the png_info structure with all the data you
wish to write before the actual image. Note that the only thing you
are allowed to write after the image is the text chunks and the time
-chunk (as of PNG Specification 1.0, anyway). See png_write_end() and
+chunk (as of PNG Specification 1.2, anyway). See png_write_end() and
the latest PNG specification for more information on that. If you
wish to write them before the image, fill them in now, and flag that
data as being valid. If you want to wait until after the data, don't
@@ -1978,7 +2202,21 @@
row_info, png_bytep data)
See pngtest.c for a working example. Your function will be called
-before any of the other transformations have been processed.
+before any of the other transformations are processed.
+
+You can also set up a pointer to a user structure for use by your
+callback function.
+
+ png_set_user_transform_info(png_ptr, user_ptr, 0, 0);
+
+The user_channels and user_depth parameters of this function are ignored
+when writing; you can set them to zero as shown.
+
+You can retrieve the pointer via the function
+png_get_user_transform_ptr(). For example:
+
+ voidp write_user_transform_ptr =
+ png_get_user_transform_ptr(png_ptr);
It is possible to have libpng flush any pending output, either manually,
or automatically after a certain number of lines have been written. To
@@ -2035,8 +2273,8 @@
png_write_row(png_ptr, &row_pointer);
When the file is interlaced, things can get a good deal more
-complicated. The only currently (as of February 1998 -- PNG Specification
-version 1.0, dated October 1996) defined interlacing scheme for PNG files
+complicated. The only currently (as of August 1999 -- PNG Specification
+version 1.2, dated July 1999) defined interlacing scheme for PNG files
is the "Adam7" interlace scheme, that breaks down an
image into seven smaller images of varying size. libpng will build
these images for you, or you can do them yourself. If you want to
@@ -2081,7 +2319,6 @@
For a more compact example of writing a PNG image, see the file example.c.
-
.SH V. Modifying/Customizing libpng:
There are two issues here. The first is changing how libpng does
@@ -2108,7 +2345,8 @@
png_struct and is initialized via png_init_io(). If you wish to change
the method of I/O, the library supplies callbacks that you can set
through the function png_set_read_fn() and png_set_write_fn() at run
-time, instead of calling the png_init_io() function. These functions
+time, instead of calling the png_init_io() function.
+These functions
also provide a void pointer that can be retrieved via the function
png_get_io_ptr(). For example:
@@ -2275,7 +2513,7 @@
for any images with bit depths less than 8 bits/pixel.
The 'method' parameter sets the main filtering method, which is
-currently only '0' in the PNG 1.0 specification. The 'filters'
+currently only '0' in the PNG 1.2 specification. The 'filters'
parameter sets which filter(s), if any, should be used for each
scanline. Possible values are PNG_ALL_FILTERS and PNG_NO_FILTERS
to turn filtering on and off, respectively.
@@ -2444,9 +2682,9 @@
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 0.81 and
-upward are Y2K compliant. It is my belief that earlier versions were
-also Y2K compliant.
+This is your unofficial assurance that libpng from version 0.71 and
+upward through 1.0.4 are Y2K compliant. It is my belief that earlier
+versions were also Y2K compliant.
Libpng only has three year fields. One is a 2-byte unsigned integer that
will hold years up to 65535. The other two hold the date in text
@@ -2475,15 +2713,18 @@
clock time, which returns (year - 1900), which we properly convert to
the full 4-digit year. There is a possibility that applications using
libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
-function, or incorrectly passing only a 2-digit year instead of
-"year - 1900" into the png_convert_from_struct_tm() function, but this
-is not under our control. The libpng documentation has always stated
-that it works with 4-digit years, and the APIs have been documented as
-such.
+function, or that they are incorrectly passing only a 2-digit year
+instead of "year - 1900" into the png_convert_from_struct_tm() function,
+but this is not under our control. The libpng documentation has always
+stated that it works with 4-digit years, and the APIs have been
+documented as such.
The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned
integer to hold the year, and can hold years as large as 65535.
+zlib, upon which libpng depends, is also Y2K compliant. It contains
+no date-related code.
+
Glenn Randers-Pehrson
libpng maintainer
@@ -2560,13 +2801,13 @@
.SH AUTHORS
This man page: Glenn Randers-Pehrson
-<randeg@alumni.rpi.edu>
+<randeg@alum.rpi.edu>
Contributing Authors: John Bowler, Kevin Bracey, Sam Bushell, Andreas Dilger,
Magnus Holmgren, Tom Lane, Dave Martindale, Glenn Randers-Pehrson,
Greg Roelofs, Guy Eric Schalnat, Paul Schmidt, Tom Tanner, Willem van
Schaik, Tim Wegner.
-<png-implement@dworkin.wustl.edu>
+<png-implement@ccrc.wustl.edu>
The contributing authors would like to thank all those who helped
with testing, bug fixes, and patience. This wouldn't have been
@@ -2574,19 +2815,19 @@
Thanks to Frank J. T. Wojcik for helping with the documentation.
-Libpng version 1.0.3 - January 14, 1999:
+Libpng version 1.0.4 - September 17, 1999:
Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
-Currently maintained by Glenn Randers-Pehrson (randeg@alumni.rpi.edu).
+Currently maintained by Glenn Randers-Pehrson (randeg@alum.rpi.edu).
Supported by the PNG development group
.br
-(png-implement@dworkin.wustl.edu).
+(png-implement@ccrc.wustl.edu).
.SH COPYRIGHT NOTICE:
-Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-Copyright (c) 1996, 1997 Andreas Dilger
Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+Copyright (c) 1996, 1997 Andreas Dilger
+Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
The PNG Reference Library (libpng) is supplied "AS IS". The Contributing
Authors and Group 42, Inc. disclaim all warranties, expressed or implied,
@@ -2617,5 +2858,13 @@
source code in a product, acknowledgment is not required but would be
appreciated.
+A "png_get_copyright" function is available, for convenient use in "about"
+boxes and the like:
+
+ printf("%s",png_get_copyright(NULL));
+
+Also, the PNG logo (in PNG format, of course) is supplied in the
+file "pngnow.png".
+
.\" end of man page
