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[alpha] Sync with libpng-1.4.0beta107

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This commit is contained in:
Glenn Randers-Pehrson
2009-12-04 13:03:56 -06:00
parent 7ce8e2e8ad
commit 95a87425bb
67 changed files with 210 additions and 172 deletions
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72
pngrtran.c
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@@ -1,7 +1,7 @@
/* pngrtran.c - transforms the data in a row for PNG readers
*
* Last changed in libpng 1.4.0 [November 29, 2009]
* Last changed in libpng 1.4.0 [December 4, 2009]
* Copyright (c) 1998-2009 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.)
@@ -16,6 +16,7 @@
* in pngtrans.c.
*/
#define PNG_NO_PEDANTIC_WARNINGS
#include "png.h"
#ifdef PNG_READ_SUPPORTED
#include "pngpriv.h"
@@ -142,21 +143,15 @@ png_set_strip_alpha(png_structp png_ptr)
#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
void PNGAPI
png_set_premultiply_alpha(png_structp png_ptr, double gamma)
png_set_premultiply_alpha(png_structp png_ptr)
{
png_debug(1, "in png_set_premultiply_alpha");
if(png_ptr == NULL)
return;
png_ptr->transformations |=
(PNG_PREMULTIPLY_ALPHA | PNG_EXPAND_tRNS);
png_ptr->transformations |=
PNG_EXPAND;
(PNG_PREMULTIPLY_ALPHA | PNG_EXPAND_tRNS | PNG_EXPAND);
png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
/* Check for overflow */
if (gamma == 0 || gamma > 21474.83)
png_error(png_ptr, "Invalid gamma for premultiply");
png_ptr->gamma_premultiply = (float)gamma;
}
#endif
@@ -758,7 +753,7 @@ png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
#endif
/* Initialize everything needed for the read. This includes modifying
* the palette.
* the palette and building any needed gamma tables.
*/
void /* PRIVATE */
png_init_read_transformations(png_structp png_ptr)
@@ -1531,25 +1526,23 @@ png_do_read_transformations(png_structp png_ptr)
#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
/* TO DO: build 16-bit gamma tables */
if (png_ptr->transformations & PNG_PREMULTIPLY_ALPHA)
png_do_read_premultiply_alpha(&(png_ptr->row_info),
png_ptr->row_buf + 1);
{
png_do_gamma(&(png_ptr->row_info), png_ptr->row_buf + 1,
png_ptr->gamma_table, png_ptr->gamma_16_table,
png_ptr->gamma_shift);
/* TO DO: apply png_ptr->gamma_premultiply to the premultiplied
* samples, using the 16-bit gamma table. We may need to set
* png_ptr->screen_gamma to our output gamma, even though it is
* not necessarily destined to a screen.
*/
png_do_read_premultiply_alpha(&(png_ptr->row_info),
png_ptr->row_buf + 1, png_ptr->gamma_16_to_1);
# ifdef PNG_READ_16_TO_8_SUPPORTED
if (!(png_ptr->transformations & PNG_PREMULTIPLY_ALPHA))
{
if (png_ptr->transformations & PNG_16_TO_8)
png_do_chop(&(png_ptr->row_info), png_ptr->row_buf + 1);
}
if (!(png_ptr->transformations & PNG_PREMULTIPLY_ALPHA))
{
if (png_ptr->transformations & PNG_16_TO_8)
png_do_chop(&(png_ptr->row_info), png_ptr->row_buf + 1);
}
# endif
}
#endif
@@ -2043,7 +2036,8 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
void /* PRIVATE */
png_do_read_premultiply_alpha(png_row_infop row_info, png_bytep row)
png_do_read_premultiply_alpha(png_row_infop row_info, png_bytep row,
png_uint_16pp gamma_16_to_1)
{
/* TO DO: apply gamma before premultiply */
@@ -2063,9 +2057,12 @@ png_do_read_premultiply_alpha(png_row_infop row_info, png_bytep row)
for (i = 0; i < row_width; i++)
{
a = *(--sp); --dp;
sp--; *(--dp) = PNG_16_BIT_PREMULTIPLY((*sp), a);
sp--; *(--dp) = PNG_16_BIT_PREMULTIPLY((*sp), a);
sp--; *(--dp) = PNG_16_BIT_PREMULTIPLY((*sp), a);
sp--; *(--dp) = gamma_16_to_1[(int)(*sp)];
*(dp) = PNG_16_BIT_PREMULTIPLY((*dp), a);
sp--; *(--dp) = gamma_16_to_1[(int)(*sp)];
*(dp) = PNG_16_BIT_PREMULTIPLY((*dp), a);
sp--; *(--dp) = gamma_16_to_1[*sp];
*(dp) = PNG_16_BIT_PREMULTIPLY((*dp), a);
}
}
}
@@ -2080,7 +2077,8 @@ png_do_read_premultiply_alpha(png_row_infop row_info, png_bytep row)
for (i = 0; i < row_width; i++)
{
a = *(--sp); --dp;
sp--; *(--dp) = PNG_16_BIT_PREMULTIPLY((*sp), a);
sp--; *(--dp) = gamma_16_to_1[*sp];
*(dp) = PNG_16_BIT_PREMULTIPLY((*dp), a);
}
}
}
@@ -4022,17 +4020,23 @@ static PNG_CONST int png_gamma_shift[] =
* OR
*
* RGB_to_gray transformation is being performed
*
* }
*
* AND
* {
* the screen_gamma is different from the reciprocal of the
* file_gamma by more than the specified threshold
* the screen_gamma is different from the reciprocal of
* the file_gamma by more than the specified threshold
*
* OR
*
* a background color has been specified and the file_gamma
* and screen_gamma are not 1.0, within the specified threshold.
*
* OR
*
* premultiplication by alpha is being performed and the file_gamma
* and postmultiply_gamma are not 1.0, within the specified threshold.
* }
*/
@@ -4096,7 +4100,12 @@ png_build_gamma_table(png_structp png_ptr)
}
#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */
}
#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
if (png_ptr->transformations & PNG_PREMULTIPLY_ALPHA)
#else
else
#endif
{
double g;
int i, j, shift, num;
@@ -4201,6 +4210,7 @@ png_build_gamma_table(png_structp png_ptr)
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
/* PREMULTIPLY */
if (png_ptr->transformations & (PNG_BACKGROUND | PNG_RGB_TO_GRAY))
{