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Imported from libpng-0.97.tar

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Glenn Randers-Pehrson
1998-01-01 07:13:13 -06:00
parent 47a0c422ca
commit b6ce43d6ff
24 changed files with 1297 additions and 763 deletions
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43
pngwtran.c
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@@ -1,18 +1,19 @@
/* pngwtran.c - transforms the data in a row for PNG writers
libpng 1.0 beta 6 - version 0.96
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
May 12, 1997
*/
*
* libpng 1.00.97
* 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
* May 28, 1997
*/
#define PNG_INTERNAL
#include "png.h"
/* transform the data according to the users wishes. The order of
transformations is significant. */
/* Transform the data according to the users wishes. The order of
* transformations is significant.
*/
void
png_do_write_transformations(png_structp png_ptr)
{
@@ -51,9 +52,10 @@ png_do_write_transformations(png_structp png_ptr)
}
#if defined(PNG_WRITE_PACK_SUPPORTED)
/* pack pixels into bytes. Pass the true bit depth in bit_depth. The
row_info bit depth should be 8 (one pixel per byte). The channels
should be 1 (this only happens on grayscale and paletted images) */
/* Pack pixels into bytes. Pass the true bit depth in bit_depth. The
* row_info bit depth should be 8 (one pixel per byte). The channels
* should be 1 (this only happens on grayscale and paletted images).
*/
void
png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
{
@@ -169,12 +171,13 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
#endif
#if defined(PNG_WRITE_SHIFT_SUPPORTED)
/* shift pixel values to take advantage of whole range. Pass the
true number of bits in bit_depth. The row should be packed
according to row_info->bit_depth. Thus, if you had a row of
bit depth 4, but the pixels only had values from 0 to 7, you
would pass 3 as bit_depth, and this routine would translate the
data to 0 to 15. */
/* Shift pixel values to take advantage of whole range. Pass the
* true number of bits in bit_depth. The row should be packed
* according to row_info->bit_depth. Thus, if you had a row of
* bit depth 4, but the pixels only had values from 0 to 7, you
* would pass 3 as bit_depth, and this routine would translate the
* data to 0 to 15.
*/
void
png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
{
@@ -252,7 +255,7 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
for (bp = row, i = 0; i < row_info->width; i++)
{
int c;
png_uint_32 c;
for (c = 0; c < channels; c++, bp++)
{
@@ -278,7 +281,7 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
for (bp = row, i = 0; i < row_info->width * row_info->channels; i++)
{
int c;
png_uint_32 c;
for (c = 0; c < channels; c++, bp += 2)
{