mewin/libpng
1
0
Fork 0
mirror of https://git.code.sf.net/p/libpng/code.git synced 2025-07-10 18:04:09 +02:00
Code Issues Projects Releases Wiki Activity

[master] Imported from libpng-1.6.0.tar

Browse Source
This commit is contained in:
Glenn Randers-Pehrson
2013-02-13 22:49:19 -06:00
parent d14caad2e9
commit 0da9cf38cd
150 changed files with 26368 additions and 49002 deletions
Download Patch File Download Diff File Expand all files Collapse all files

127
pngtrans.c
View File

@@ -1,8 +1,8 @@
/* pngtrans.c - transforms the data in a row (used by both readers and writers)
*
* Last changed in libpng 1.5.11 [June 14, 2012]
* Copyright (c) 1998-2012 Glenn Randers-Pehrson
* Last changed in libpng 1.6.0 [February 14, 2013]
* Copyright (c) 1998-2013 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.)
*
@@ -18,7 +18,7 @@
#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
/* Turn on BGR-to-RGB mapping */
void PNGAPI
png_set_bgr(png_structp png_ptr)
png_set_bgr(png_structrp png_ptr)
{
png_debug(1, "in png_set_bgr");
@@ -32,7 +32,7 @@ png_set_bgr(png_structp png_ptr)
#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
/* Turn on 16 bit byte swapping */
void PNGAPI
png_set_swap(png_structp png_ptr)
png_set_swap(png_structrp png_ptr)
{
png_debug(1, "in png_set_swap");
@@ -47,7 +47,7 @@ png_set_swap(png_structp png_ptr)
#if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
/* Turn on pixel packing */
void PNGAPI
png_set_packing(png_structp png_ptr)
png_set_packing(png_structrp png_ptr)
{
png_debug(1, "in png_set_packing");
@@ -65,7 +65,7 @@ png_set_packing(png_structp png_ptr)
#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
/* Turn on packed pixel swapping */
void PNGAPI
png_set_packswap(png_structp png_ptr)
png_set_packswap(png_structrp png_ptr)
{
png_debug(1, "in png_set_packswap");
@@ -79,7 +79,7 @@ png_set_packswap(png_structp png_ptr)
#if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
void PNGAPI
png_set_shift(png_structp png_ptr, png_const_color_8p true_bits)
png_set_shift(png_structrp png_ptr, png_const_color_8p true_bits)
{
png_debug(1, "in png_set_shift");
@@ -94,7 +94,7 @@ png_set_shift(png_structp png_ptr, png_const_color_8p true_bits)
#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
defined(PNG_WRITE_INTERLACING_SUPPORTED)
int PNGAPI
png_set_interlace_handling(png_structp png_ptr)
png_set_interlace_handling(png_structrp png_ptr)
{
png_debug(1, "in png_set_interlace handling");
@@ -115,44 +115,91 @@ png_set_interlace_handling(png_structp png_ptr)
* that don't like bytes as parameters.
*/
void PNGAPI
png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc)
png_set_filler(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
{
png_debug(1, "in png_set_filler");
if (png_ptr == NULL)
return;
/* In libpng 1.6 it is possible to determine whether this is a read or write
* operation and therefore to do more checking here for a valid call.
*/
if (png_ptr->mode & PNG_IS_READ_STRUCT)
{
# ifdef PNG_READ_FILLER_SUPPORTED
/* On read png_set_filler is always valid, regardless of the base PNG
* format, because other transformations can give a format where the
* filler code can execute (basically an 8 or 16-bit component RGB or G
* format.)
*
* NOTE: usr_channels is not used by the read code! (This has led to
* confusion in the past.) The filler is only used in the read code.
*/
png_ptr->filler = (png_uint_16)filler;
# else
png_app_error(png_ptr, "png_set_filler not supported on read");
PNG_UNUSED(filler) /* not used in the write case */
return;
# endif
}
else /* write */
{
# ifdef PNG_WRITE_FILLER_SUPPORTED
/* On write the usr_channels parameter must be set correctly at the
* start to record the number of channels in the app-supplied data.
*/
switch (png_ptr->color_type)
{
case PNG_COLOR_TYPE_RGB:
png_ptr->usr_channels = 4;
break;
case PNG_COLOR_TYPE_GRAY:
if (png_ptr->bit_depth >= 8)
{
png_ptr->usr_channels = 2;
break;
}
else
{
/* There simply isn't any code in libpng to strip out bits
* from bytes when the components are less than a byte in
* size!
*/
png_app_error(png_ptr,
"png_set_filler is invalid for low bit depth gray output");
return;
}
default:
png_app_error(png_ptr,
"png_set_filler: inappropriate color type");
return;
}
# else
png_app_error(png_ptr, "png_set_filler not supported on write");
return;
# endif
}
/* Here on success - libpng supports the operation, set the transformation
* and the flag to say where the filler channel is.
*/
png_ptr->transformations |= PNG_FILLER;
png_ptr->filler = (png_uint_16)filler;
if (filler_loc == PNG_FILLER_AFTER)
png_ptr->flags |= PNG_FLAG_FILLER_AFTER;
else
png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER;
/* This should probably go in the "do_read_filler" routine.
* I attempted to do that in libpng-1.0.1a but that caused problems
* so I restored it in libpng-1.0.2a
*/
if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
{
png_ptr->usr_channels = 4;
}
/* Also I added this in libpng-1.0.2a (what happens when we expand
* a less-than-8-bit grayscale to GA?) */
if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8)
{
png_ptr->usr_channels = 2;
}
}
/* Added to libpng-1.2.7 */
void PNGAPI
png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc)
png_set_add_alpha(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
{
png_debug(1, "in png_set_add_alpha");
@@ -160,7 +207,9 @@ png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc)
return;
png_set_filler(png_ptr, filler, filler_loc);
png_ptr->transformations |= PNG_ADD_ALPHA;
/* The above may fail to do anything. */
if (png_ptr->transformations & PNG_FILLER)
png_ptr->transformations |= PNG_ADD_ALPHA;
}
#endif
@@ -168,7 +217,7 @@ png_set_add_alpha(png_structp png_ptr, png_uint_32 filler, int filler_loc)
#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
void PNGAPI
png_set_swap_alpha(png_structp png_ptr)
png_set_swap_alpha(png_structrp png_ptr)
{
png_debug(1, "in png_set_swap_alpha");
@@ -182,7 +231,7 @@ png_set_swap_alpha(png_structp png_ptr)
#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
void PNGAPI
png_set_invert_alpha(png_structp png_ptr)
png_set_invert_alpha(png_structrp png_ptr)
{
png_debug(1, "in png_set_invert_alpha");
@@ -195,7 +244,7 @@ png_set_invert_alpha(png_structp png_ptr)
#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
void PNGAPI
png_set_invert_mono(png_structp png_ptr)
png_set_invert_mono(png_structrp png_ptr)
{
png_debug(1, "in png_set_invert_mono");
@@ -623,7 +672,7 @@ png_do_bgr(png_row_infop row_info, png_bytep row)
defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
/* Added at libpng-1.5.10 */
void /* PRIVATE */
png_do_check_palette_indexes(png_structp png_ptr, png_row_infop row_info)
png_do_check_palette_indexes(png_structrp png_ptr, png_row_infop row_info)
{
if (png_ptr->num_palette < (1 << row_info->bit_depth) &&
png_ptr->num_palette > 0) /* num_palette can be 0 in MNG files */
@@ -726,7 +775,7 @@ png_do_check_palette_indexes(png_structp png_ptr, png_row_infop row_info)
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
void PNGAPI
png_set_user_transform_info(png_structp png_ptr, png_voidp
png_set_user_transform_info(png_structrp png_ptr, png_voidp
user_transform_ptr, int user_transform_depth, int user_transform_channels)
{
png_debug(1, "in png_set_user_transform_info");
@@ -746,18 +795,18 @@ png_set_user_transform_info(png_structp png_ptr, png_voidp
*/
#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
png_voidp PNGAPI
png_get_user_transform_ptr(png_const_structp png_ptr)
png_get_user_transform_ptr(png_const_structrp png_ptr)
{
if (png_ptr == NULL)
return (NULL);
return ((png_voidp)png_ptr->user_transform_ptr);
return png_ptr->user_transform_ptr;
}
#endif
#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
png_uint_32 PNGAPI
png_get_current_row_number(png_const_structp png_ptr)
png_get_current_row_number(png_const_structrp png_ptr)
{
/* See the comments in png.h - this is the sub-image row when reading and
* interlaced image.
@@ -769,7 +818,7 @@ png_get_current_row_number(png_const_structp png_ptr)
}
png_byte PNGAPI
png_get_current_pass_number(png_const_structp png_ptr)
png_get_current_pass_number(png_const_structrp png_ptr)
{
if (png_ptr != NULL)
return png_ptr->pass;