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

Imported from libpng-1.0.1d.tar

Browse Source
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
Download Patch File Download Diff File Expand all files Collapse all files

46
pngrutil.c
View File

@@ -1,14 +1,14 @@
/* pngrutil.c - utilities to read a PNG file
*
* 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 routines which are only called from within
* This file contains routines that are only called from within
* libpng itself during the course of reading an image.
*/
@@ -16,7 +16,7 @@
#include "png.h"
#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
/* Grab an unsigned 32-bit integer from a buffer in big endian format. */
/* Grab an unsigned 32-bit integer from a buffer in big-endian format. */
png_uint_32
png_get_uint_32(png_bytep buf)
{
@@ -29,7 +29,7 @@ png_get_uint_32(png_bytep buf)
}
#if defined(PNG_READ_pCAL_SUPPORTED)
/* Grab a signed 32-bit integer from a buffer in big endian format. The
/* Grab a signed 32-bit integer from a buffer in big-endian format. The
* data is stored in the PNG file in two's complement format, and it is
* assumed that the machine format for signed integers is the same. */
png_int_32
@@ -44,7 +44,7 @@ png_get_int_32(png_bytep buf)
}
#endif /* PNG_READ_pCAL_SUPPORTED */
/* Grab an unsigned 16-bit integer from a buffer in big endian format. */
/* Grab an unsigned 16-bit integer from a buffer in big-endian format. */
png_uint_16
png_get_uint_16(png_bytep buf)
{
@@ -1724,7 +1724,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
s_inc = 1;
}
for (i = row_info->width; i; i--)
for (i = 0; i < row_info->width; i++)
{
v = (png_byte)((*sp >> sshift) & 0x1);
for (j = 0; j < jstop; j++)
@@ -1777,7 +1777,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
s_inc = 2;
}
for (i = row_info->width; i; i--)
for (i = 0; i < row_info->width; i++)
{
png_byte v;
int j;
@@ -1833,7 +1833,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
s_inc = 4;
}
for (i = row_info->width; i; i--)
for (i = 0; i < row_info->width; i++)
{
png_byte v = (png_byte)((*sp >> sshift) & 0xf);
int j;
@@ -1868,7 +1868,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
int jstop = png_pass_inc[pass];
png_uint_32 i;
for (i = row_info->width; i; i--)
for (i = 0; i < row_info->width; i++)
{
png_byte v[8];
int j;
@@ -1914,7 +1914,8 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
for (i = bpp; i < istop; i++)
{
*rp++ = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);
*rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);
rp++;
}
break;
}
@@ -1927,7 +1928,8 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
for (i = 0; i < istop; i++)
{
*rp++ = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
*rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
rp++;
}
break;
}
@@ -1938,18 +1940,20 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
png_bytep pp = prev_row;
png_bytep lp = row;
png_uint_32 bpp = (row_info->pixel_depth + 7) / 8;
png_uint_32 istop = row_info->rowbytes;
png_uint_32 istop = row_info->rowbytes - bpp;
for (i = 0; i < bpp; i++)
{
*rp++ = (png_byte)(((int)(*rp) +
*rp = (png_byte)(((int)(*rp) +
((int)(*pp++) / 2)) & 0xff);
rp++;
}
for (lp = row; i < istop; i++)
for (i = 0; i < istop; i++)
{
*rp++ = (png_byte)(((int)(*rp) +
*rp = (png_byte)(((int)(*rp) +
(int)(*pp++ + *lp++) / 2) & 0xff);
rp++;
}
break;
}
@@ -1961,14 +1965,15 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
png_bytep lp = row;
png_bytep cp = prev_row;
png_uint_32 bpp = (row_info->pixel_depth + 7) / 8;
png_uint_32 istop=row_info->rowbytes;
png_uint_32 istop=row_info->rowbytes - bpp;
for (i = 0; i < bpp; i++)
{
*rp++ = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
*rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
rp++;
}
for ( ; i < istop; i++) /* use leftover i,rp,pp */
for (i = 0; i < istop; i++) /* use leftover rp,pp */
{
int a, b, c, pa, pb, pc, p;
@@ -2000,7 +2005,8 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
*rp++ = (png_byte)(((int)(*rp) + p) & 0xff);
*rp = (png_byte)(((int)(*rp) + p) & 0xff);
rp++;
}
break;
}