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Imported from libpng-1.0.1d.tar

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This commit is contained in:
Glenn Randers-Pehrson
1998-05-21 09:27:50 -05:00
parent d0dce40075
commit 8686fff347
35 changed files with 1252 additions and 182 deletions
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70
pngrtran.c
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@@ -1,16 +1,16 @@
/* pngrtran.c - transforms the data in a row for PNG readers
*
* 1.0.1c
* 1.0.1d
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
* Copyright (c) 1996, 1997 Andreas Dilger
* Copyright (c) 1998, Glenn Randers-Pehrson
* May 9, 1998
* May 21, 1998
*
* This file contains functions optionally called by an application
* in order to tell libpng how to handle data when reading a PNG.
* Transformations which are used in both reading and writing are
* Transformations that are used in both reading and writing are
* in pngtrans.c.
*/
@@ -208,11 +208,11 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
/* swap the palette around, and set up a table, if necessary */
if (full_dither)
{
int j;
int j = num_palette;
/* put all the useful colors within the max, but don't
move the others */
for (i = 0, j = num_palette; i < maximum_colors; i++)
for (i = 0; i < maximum_colors; i++)
{
if ((int)sort[i] >= maximum_colors)
{
@@ -225,11 +225,11 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
}
else
{
int j;
int j = num_palette;
/* move all the used colors inside the max limit, and
develop a translation table */
for (i = 0, j = num_palette; i < maximum_colors; i++)
for (i = 0; i < maximum_colors; i++)
{
/* only move the colors we need to */
if ((int)sort[i] >= maximum_colors)
@@ -576,16 +576,19 @@ png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
void
png_init_read_transformations(png_structp png_ptr)
{
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if(png_ptr == NULL) return;
#endif
png_debug(1, "in png_init_read_transformations\n");
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if(png_ptr != NULL)
#endif
{
#if defined(PNG_READ_BACKGROUND_SUPPORTED) || defined(PNG_READ_SHIFT_SUPPORTED) \
|| defined(PNG_READ_GAMMA_SUPPORTED)
int color_type = png_ptr->color_type;
#endif
#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED)
if (png_ptr->transformations & PNG_BACKGROUND_EXPAND)
{
int color_type = png_ptr->color_type;
if (!(color_type & PNG_COLOR_MASK_COLOR)) /* i.e., GRAY or GRAY_ALPHA */
{
/* expand background chunk. */
@@ -881,6 +884,7 @@ png_init_read_transformations(png_structp png_ptr)
}
}
#endif
}
}
/* Modify the info structure to reflect the transformations. The
@@ -1334,19 +1338,20 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
}
case 4:
{
png_bytep bp;
png_bytep bp = row;
png_uint_32 i;
png_uint_32 istop = row_info->rowbytes;
png_byte mask = (png_byte)(((int)0xf0 >> shift[0]) & (int)0xf0) |
(png_byte)((int)0xf >> shift[0]);
for (bp = row, i = 0; i < istop; i++)
for (i = 0; i < istop; i++)
{
*bp >>= shift[0];
*bp++ &= mask;
}
break;
}
#ifndef PNG_SLOW_SHIFT
case 8:
{
png_bytep bp = row;
@@ -1374,6 +1379,43 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
}
break;
}
#else
case 8:
{
png_bytep bp;
png_uint_32 i;
int cstop;
cstop=(int)row_info->channels;
for (bp = row, i = 0; i < row_width; i++)
{
for (c = 0; c < cstop; c++, bp++)
{
*bp >>= shift[c];
}
}
break;
}
case 16:
{
png_bytep bp;
png_size_t i;
int cstop;
cstop=(int)row_info->channels;
for (bp = row, i = 0; i < row_width; i++)
{
for (c = 0; c < cstop; c++, bp += 2)
{
value = (png_uint_16)((*bp << 8) + *(bp + 1));
value >>= shift[c];
*bp = (png_byte)(value >> 8);
*(bp + 1) = (png_byte)(value & 0xff);
}
}
break;
}
#endif
}
}
}