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Imported from libpng-1.0.1c.tar

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This commit is contained in:
Glenn Randers-Pehrson
1998-05-09 10:02:29 -05:00
parent 1d96361273
commit d0dce40075
30 changed files with 373 additions and 200 deletions
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51
pngrtran.c
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@@ -1,12 +1,12 @@
/* pngrtran.c - transforms the data in a row for PNG readers
*
* libpng 1.0.1b
* 1.0.1c
* 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 2, 1998
* May 9, 1998
*
* This file contains functions optionally called by an application
* in order to tell libpng how to handle data when reading a PNG.
@@ -576,13 +576,16 @@ png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
void
png_init_read_transformations(png_structp png_ptr)
{
int color_type = png_ptr->color_type;
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if(png_ptr == NULL) return;
#endif
png_debug(1, "in png_init_read_transformations\n");
#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. */
@@ -1322,10 +1325,10 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
png_uint_32 i;
png_uint_32 istop = row_info->rowbytes;
for (bp = row, i = 0; i < istop; i++, bp++)
for (bp = row, i = 0; i < istop; i++)
{
*bp >>= 1;
*bp &= 0x55;
*bp++ &= 0x55;
}
break;
}
@@ -1337,43 +1340,37 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
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++, bp++)
for (bp = row, i = 0; i < istop; i++)
{
*bp >>= shift[0];
*bp &= mask;
*bp++ &= mask;
}
break;
}
case 8:
{
png_bytep bp;
png_bytep bp = row;
png_uint_32 i;
int cstop=(int)row_info->channels;
png_uint_32 istop = row_width * channels;
for (bp = row, i = 0; i < row_width; i++)
for (i = 0; i < istop; i++)
{
for (c = 0; c < cstop; c++, bp++)
{
*bp >>= shift[c];
}
*bp++ >>= shift[i%channels];
}
break;
}
case 16:
{
png_bytep bp;
png_size_t i;
int cstop=(int)row_info->channels;
png_bytep bp = row;
png_uint_32 i;
png_uint_32 istop = channels * row_width;
for (bp = row, i = 0; i < row_width; i++)
for (i = 0; i < istop; 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);
}
value = (png_uint_16)((*bp << 8) + *(bp + 1));
value >>= shift[i%channels];
*bp++ = (png_byte)(value >> 8);
*bp++ = (png_byte)(value & 0xff);
}
break;
}
@@ -1620,8 +1617,8 @@ png_do_read_filler(png_row_infop row_info, png_bytep row,
png_uint_32 i;
png_uint_32 row_width = row_info->width;
png_byte hi_filler = (png_byte)((filler>>8) & 0xf);
png_byte low_filler = (png_byte)(filler & 0xf);
png_byte hi_filler = (png_byte)((filler>>8) & 0xff);
png_byte low_filler = (png_byte)(filler & 0xff);
png_debug(1, "in png_do_read_filler\n");
if (