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Imported from libpng-1.0.1b.tar

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This commit is contained in:
Glenn Randers-Pehrson
1998-05-02 12:52:25 -05:00
parent 896239be20
commit 1d96361273
29 changed files with 837 additions and 710 deletions
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270
pngrutil.c
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@@ -1,12 +1,12 @@
/* pngrutil.c - utilities to read a PNG file
*
* libpng 1.0.1a
* 1.0.1b
* 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
* April 21, 1998
* May 2, 1998
*
* This file contains routines which are only called from within
* libpng itself during the course of reading an image.
@@ -20,9 +20,7 @@
png_uint_32
png_get_uint_32(png_bytep buf)
{
png_uint_32 i;
i = ((png_uint_32)(*buf) << 24) +
png_uint_32 i = ((png_uint_32)(*buf) << 24) +
((png_uint_32)(*(buf + 1)) << 16) +
((png_uint_32)(*(buf + 2)) << 8) +
(png_uint_32)(*(buf + 3));
@@ -37,9 +35,7 @@ png_get_uint_32(png_bytep buf)
png_int_32
png_get_int_32(png_bytep buf)
{
png_int_32 i;
i = ((png_int_32)(*buf) << 24) +
png_int_32 i = ((png_int_32)(*buf) << 24) +
((png_int_32)(*(buf + 1)) << 16) +
((png_int_32)(*(buf + 2)) << 8) +
(png_int_32)(*(buf + 3));
@@ -52,9 +48,7 @@ png_get_int_32(png_bytep buf)
png_uint_16
png_get_uint_16(png_bytep buf)
{
png_uint_16 i;
i = (png_uint_16)(((png_uint_16)(*buf) << 8) +
png_uint_16 i = (png_uint_16)(((png_uint_16)(*buf) << 8) +
(png_uint_16)(*(buf + 1)));
return (i);
@@ -76,16 +70,16 @@ png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length)
int
png_crc_finish(png_structp png_ptr, png_uint_32 skip)
{
png_uint_32 i,istop;
png_size_t i;
png_size_t istop = png_ptr->zbuf_size;
istop = (png_uint_32)png_ptr->zbuf_size;
for (i = skip; i > istop; i -= istop)
{
png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
}
if (i)
{
png_crc_read(png_ptr, png_ptr->zbuf, (png_size_t)i);
png_crc_read(png_ptr, png_ptr->zbuf, i);
}
if (png_crc_error(png_ptr))
@@ -1500,16 +1494,14 @@ png_combine_row(png_structp png_ptr, png_bytep row,
{
case 1:
{
png_bytep sp;
png_bytep dp;
png_bytep sp = png_ptr->row_buf + 1;
png_bytep dp = row;
int s_inc, s_start, s_end;
int m;
int m = 0x80;
int shift;
png_uint_32 i, istop;
png_uint_32 i;
png_uint_32 row_width = png_ptr->width;
sp = png_ptr->row_buf + 1;
dp = row;
m = 0x80;
#if defined(PNG_READ_PACKSWAP_SUPPORTED)
if (png_ptr->transformations & PNG_PACKSWAP)
{
@@ -1527,8 +1519,7 @@ png_combine_row(png_structp png_ptr, png_bytep row,
shift = s_start;
istop = png_ptr->width;
for (i = 0; i < istop; i++)
for (i = 0; i < row_width; i++)
{
if (m & mask)
{
@@ -1557,17 +1548,15 @@ png_combine_row(png_structp png_ptr, png_bytep row,
}
case 2:
{
png_bytep sp;
png_bytep dp;
png_bytep sp = png_ptr->row_buf + 1;
png_bytep dp = row;
int s_start, s_end, s_inc;
int m;
int m = 0x80;
int shift;
png_uint_32 i,istop;
png_uint_32 i;
png_uint_32 row_width = png_ptr->width;
int value;
sp = png_ptr->row_buf + 1;
dp = row;
m = 0x80;
#if defined(PNG_READ_PACKSWAP_SUPPORTED)
if (png_ptr->transformations & PNG_PACKSWAP)
{
@@ -1585,8 +1574,7 @@ png_combine_row(png_structp png_ptr, png_bytep row,
shift = s_start;
istop = png_ptr->width;
for (i = 0; i < istop; i++)
for (i = 0; i < row_width; i++)
{
if (m & mask)
{
@@ -1612,17 +1600,15 @@ png_combine_row(png_structp png_ptr, png_bytep row,
}
case 4:
{
png_bytep sp;
png_bytep dp;
png_bytep sp = png_ptr->row_buf + 1;
png_bytep dp = row;
int s_start, s_end, s_inc;
int m;
int m = 0x80;
int shift;
png_uint_32 i,istop;
png_uint_32 i;
png_uint_32 row_width = png_ptr->width;
int value;
sp = png_ptr->row_buf + 1;
dp = row;
m = 0x80;
#if defined(PNG_READ_PACKSWAP_SUPPORTED)
if (png_ptr->transformations & PNG_PACKSWAP)
{
@@ -1639,8 +1625,7 @@ png_combine_row(png_structp png_ptr, png_bytep row,
}
shift = s_start;
istop = png_ptr->width;
for (i = 0; i < istop; i++)
for (i = 0; i < row_width; i++)
{
if (m & mask)
{
@@ -1666,19 +1651,15 @@ png_combine_row(png_structp png_ptr, png_bytep row,
}
default:
{
png_bytep sp;
png_bytep dp;
png_size_t pixel_bytes;
png_uint_32 i, istop;
png_byte m;
png_bytep sp = png_ptr->row_buf + 1;
png_bytep dp = row;
png_size_t pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
png_uint_32 i;
png_uint_32 row_width = png_ptr->width;
png_byte m = 0x80;
pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
sp = png_ptr->row_buf + 1;
dp = row;
m = 0x80;
istop = png_ptr->width;
for (i = 0; i < istop; i++)
for (i = 0; i < row_width; i++)
{
if (m & mask)
{
@@ -1715,15 +1696,15 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
{
case 1:
{
png_bytep sp, dp;
png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3);
png_bytep dp = row + (png_size_t)((final_width - 1) >> 3);
int sshift, dshift;
int s_start, s_end, s_inc;
int jstop = png_pass_inc[pass];
png_byte v;
png_uint_32 i;
int j, jstop;
int j;
sp = row + (png_size_t)((row_info->width - 1) >> 3);
dp = row + (png_size_t)((final_width - 1) >> 3);
#if defined(PNG_READ_PACKSWAP_SUPPORTED)
if (transformations & PNG_PACKSWAP)
{
@@ -1743,7 +1724,6 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
s_inc = 1;
}
jstop = png_pass_inc[pass];
for (i = row_info->width; i; i--)
{
v = (png_byte)((*sp >> sshift) & 0x1);
@@ -1771,14 +1751,13 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
}
case 2:
{
png_bytep sp, dp;
png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2);
png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2);
int sshift, dshift;
int s_start, s_end, s_inc;
int jstop = png_pass_inc[pass];
png_uint_32 i;
int jstop;
sp = row + (png_uint_32)((row_info->width - 1) >> 2);
dp = row + (png_uint_32)((final_width - 1) >> 2);
#if defined(PNG_READ_PACKSWAP_SUPPORTED)
if (transformations & PNG_PACKSWAP)
{
@@ -1798,7 +1777,6 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
s_inc = 2;
}
jstop = png_pass_inc[pass];
for (i = row_info->width; i; i--)
{
png_byte v;
@@ -1829,14 +1807,13 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
}
case 4:
{
png_bytep sp, dp;
png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1);
png_bytep dp = row + (png_size_t)((final_width - 1) >> 1);
int sshift, dshift;
int s_start, s_end, s_inc;
png_uint_32 i;
int jstop;
int jstop = png_pass_inc[pass];
sp = row + (png_size_t)((row_info->width - 1) >> 1);
dp = row + (png_size_t)((final_width - 1) >> 1);
#if defined(PNG_READ_PACKSWAP_SUPPORTED)
if (transformations & PNG_PACKSWAP)
{
@@ -1856,13 +1833,11 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
s_inc = 4;
}
jstop = png_pass_inc[pass];
for (i = row_info->width; i; i--)
{
png_byte v;
png_byte v = (png_byte)((*sp >> sshift) & 0xf);
int j;
v = (png_byte)((*sp >> sshift) & 0xf);
for (j = 0; j < jstop; j++)
{
*dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);
@@ -1887,16 +1862,12 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
}
default:
{
png_bytep sp, dp;
png_size_t pixel_bytes = (row_info->pixel_depth >> 3);
png_bytep sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes;
png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
int jstop = png_pass_inc[pass];
png_uint_32 i;
int jstop;
png_size_t pixel_bytes;
pixel_bytes = (row_info->pixel_depth >> 3);
sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes;
dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
jstop = png_pass_inc[pass];
for (i = row_info->width; i; i--)
{
png_byte v[8];
@@ -1935,95 +1906,87 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
break;
case PNG_FILTER_VALUE_SUB:
{
png_uint_32 i, istop;
int bpp;
png_bytep rp;
png_bytep lp;
png_uint_32 i;
png_uint_32 istop = row_info->rowbytes;
png_uint_32 bpp = (row_info->pixel_depth + 7) / 8;
png_bytep rp = row + bpp;
png_bytep lp = row;
bpp = (row_info->pixel_depth + 7) / 8;
istop = row_info->rowbytes;
for (i = (png_uint_32)bpp, rp = row + bpp, lp = row;
i < istop; i++, rp++, lp++)
for (i = bpp; i < istop; i++)
{
*rp = (png_byte)(((int)(*rp) + (int)(*lp)) & 0xff);
*rp++ = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);
}
break;
}
case PNG_FILTER_VALUE_UP:
{
png_uint_32 i, istop;
png_bytep rp;
png_bytep pp;
png_uint_32 i;
png_uint_32 istop = row_info->rowbytes;
png_bytep rp = row;
png_bytep pp = prev_row;
istop = row_info->rowbytes;
for (i = 0, rp = row, pp = prev_row; i < istop; i++, rp++, pp++)
for (i = 0; i < istop; i++)
{
*rp = (png_byte)(((int)(*rp) + (int)(*pp)) & 0xff);
*rp++ = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
}
break;
}
case PNG_FILTER_VALUE_AVG:
{
png_uint_32 i, istop;
int bpp;
png_bytep rp;
png_bytep pp;
png_bytep lp;
png_uint_32 i;
png_bytep rp = 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;
bpp = (row_info->pixel_depth + 7) / 8;
istop = (png_uint_32)bpp;
for (i = 0, rp = row, pp = prev_row; i < istop; i++, rp++, pp++)
for (i = 0; i < bpp; i++)
{
*rp = (png_byte)(((int)(*rp) +
((int)(*pp) / 2)) & 0xff);
*rp++ = (png_byte)(((int)(*rp) +
((int)(*pp++) / 2)) & 0xff);
}
istop = row_info->rowbytes;
for (lp = row; i < istop; i++, rp++,
lp++, pp++)
for (lp = row; i < istop; i++)
{
*rp = (png_byte)(((int)(*rp) +
(int)(*pp + *lp) / 2) & 0xff);
*rp++ = (png_byte)(((int)(*rp) +
(int)(*pp++ + *lp++) / 2) & 0xff);
}
break;
}
case PNG_FILTER_VALUE_PAETH:
{
int bpp;
png_uint_32 i, istop;
png_bytep rp;
png_bytep pp;
png_bytep lp;
png_bytep cp;
png_uint_32 i;
png_bytep rp = row;
png_bytep pp = prev_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;
bpp = (row_info->pixel_depth + 7) / 8;
#ifndef PNG_SLOW_PAETH
istop=bpp;
for (i = 0, rp = row, pp = prev_row; i < istop;
i++, rp++, pp++)
for (i = 0; i < bpp; i++)
{
*rp = (png_byte)(((int)(*rp) + (int)(*pp)) & 0xff);
*rp++ = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
}
istop=row_info->rowbytes;
for (lp = row, cp = prev_row; i < istop; /* use leftover i,rp,pp */
i++, rp++, pp++, lp++, cp++)
for ( ; i < istop; i++) /* use leftover i,rp,pp */
{
int a, b, c, pa, pb, pc, p;
a = *lp;
b = *pp;
c = *cp;
a = *lp++;
b = *pp++;
c = *cp++;
p = b - c;
pc = a - c;
p = a + b - c;
#ifdef PNG_USE_ABS
pa = abs(p - a);
pb = abs(p - b);
pc = abs(p - c);
pa = abs(p);
pb = abs(pc);
pc = abs(p + pc);
#else
pa = p > a ? p - a : a - p;
pb = p > b ? p - b : b - p;
pc = p > c ? p - c : c - p;
pa = p < 0 ? -p : p;
pb = pc < 0 ? -pc : pc;
pc = (p + pc) < 0 ? -(p + pc) : p + pc;
#endif
/*
@@ -2037,40 +2000,8 @@ 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);
}
#else /* PNG_SLOW_PAETH */
for (i = 0, rp = row, pp = prev_row,
lp = row - bpp, cp = prev_row - bpp,
istop = row_info->rowbytes; i < istop; i++, rp++, pp++, lp++, cp++)
{
int a, b, c, pa, pb, pc, p;
b = *pp;
if (i >= (png_uint_32)bpp)
{
c = *cp;
a = *lp;
}
else
{
a = c = 0;
}
p = a + b - c;
pa = abs(p - a);
pb = abs(p - b);
pc = abs(p - c);
if (pa <= pb && pa <= pc)
p = a;
else if (pb <= pc)
p = b;
else
p = c;
*rp = (png_byte)(((int)(*rp) + p) & 0xff);
}
#endif /* PNG_SLOW_PAETH */
break;
}
default:
@@ -2094,11 +2025,10 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
case PNG_FILTER_VALUE_SUB:
{
png_uint_32 i;
int bpp;
int bpp = (row_info->pixel_depth + 7) / 8;
png_bytep rp;
png_bytep lp;
bpp = (row_info->pixel_depth + 7) / 8;
for (i = (png_uint_32)bpp, rp = row + bpp, lp = row;
i < row_info->rowbytes; i++, rp++, lp++)
{
@@ -2122,12 +2052,11 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
case PNG_FILTER_VALUE_AVG:
{
png_uint_32 i;
int bpp;
int bpp = (row_info->pixel_depth + 7) / 8;
png_bytep rp;
png_bytep pp;
png_bytep lp;
bpp = (row_info->pixel_depth + 7) / 8;
for (i = 0, rp = row, pp = prev_row;
i < (png_uint_32)bpp; i++, rp++, pp++)
{
@@ -2143,14 +2072,13 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
}
case PNG_FILTER_VALUE_PAETH:
{
int bpp;
int bpp = (row_info->pixel_depth + 7) / 8;
png_uint_32 i;
png_bytep rp;
png_bytep pp;
png_bytep lp;
png_bytep cp;
bpp = (row_info->pixel_depth + 7) / 8;
for (i = 0, rp = row, pp = prev_row,
lp = row - bpp, cp = prev_row - bpp;
i < row_info->rowbytes; i++, rp++, pp++, lp++, cp++)