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Imported from libpng-1.0.1a.tar

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This commit is contained in:
Glenn Randers-Pehrson
1998-04-21 15:03:57 -05:00
parent f9f2fe0ce7
commit 896239be20
35 changed files with 1412 additions and 769 deletions
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263
pngrutil.c
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@@ -1,12 +1,12 @@
/* pngrutil.c - utilities to read a PNG file
*
* libpng 1.0.1
* libpng 1.0.1a
* 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
* March 15, 1998
* April 21, 1998
*
* This file contains routines which are only called from within
* libpng itself during the course of reading an image.
@@ -76,9 +76,10 @@ 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;
png_uint_32 i,istop;
for (i = skip; i > (png_uint_32)png_ptr->zbuf_size; i -= 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);
}
@@ -258,20 +259,6 @@ png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
png_ptr->mode |= PNG_HAVE_PLTE;
#if defined (PNG_READ_tRNS_SUPPORTED)
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
if (info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
{
if (png_ptr->num_trans > png_ptr->num_palette)
{
png_warning(png_ptr, "Truncating incorrect tRNS chunk length");
png_ptr->num_trans = png_ptr->num_palette;
}
}
}
#endif
#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
{
@@ -349,6 +336,21 @@ png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
png_ptr->palette = palette;
png_ptr->num_palette = (png_uint_16)num;
png_set_PLTE(png_ptr, info_ptr, palette, num);
#if defined (PNG_READ_tRNS_SUPPORTED)
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
{
if (info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
{
if (png_ptr->num_trans > png_ptr->num_palette)
{
png_warning(png_ptr, "Truncating incorrect tRNS chunk length");
png_ptr->num_trans = png_ptr->num_palette;
}
}
}
#endif
}
void
@@ -758,6 +760,12 @@ png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
png_crc_finish(png_ptr, length);
return;
}
if (length == 0)
{
png_warning(png_ptr, "Zero length tRNS chunk");
png_crc_finish(png_ptr, length);
return;
}
png_ptr->trans = (png_bytep)png_malloc(png_ptr, length);
png_ptr->flags |= PNG_FLAG_FREE_TRANS;
@@ -1075,7 +1083,7 @@ png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
purpose[slength] = 0x00; /* null terminate the last string */
png_debug(3, "Finding end of pCAL purpose string\n");
for (buf = purpose; *buf != '\0'; buf++)
for (buf = purpose; *buf; buf++)
/* empty loop */ ;
endptr = purpose + slength;
@@ -1113,7 +1121,7 @@ png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
}
for (buf = units; *buf != 0x00; buf++)
for (buf = units; *buf; buf++)
/* Empty loop to move past the units string. */ ;
png_debug(3, "Allocating pCAL parameters array\n");
@@ -1497,7 +1505,7 @@ png_combine_row(png_structp png_ptr, png_bytep row,
int s_inc, s_start, s_end;
int m;
int shift;
png_uint_32 i;
png_uint_32 i, istop;
sp = png_ptr->row_buf + 1;
dp = row;
@@ -1519,7 +1527,8 @@ png_combine_row(png_structp png_ptr, png_bytep row,
shift = s_start;
for (i = 0; i < png_ptr->width; i++)
istop = png_ptr->width;
for (i = 0; i < istop; i++)
{
if (m & mask)
{
@@ -1553,7 +1562,7 @@ png_combine_row(png_structp png_ptr, png_bytep row,
int s_start, s_end, s_inc;
int m;
int shift;
png_uint_32 i;
png_uint_32 i,istop;
int value;
sp = png_ptr->row_buf + 1;
@@ -1576,7 +1585,8 @@ png_combine_row(png_structp png_ptr, png_bytep row,
shift = s_start;
for (i = 0; i < png_ptr->width; i++)
istop = png_ptr->width;
for (i = 0; i < istop; i++)
{
if (m & mask)
{
@@ -1607,7 +1617,7 @@ png_combine_row(png_structp png_ptr, png_bytep row,
int s_start, s_end, s_inc;
int m;
int shift;
png_uint_32 i;
png_uint_32 i,istop;
int value;
sp = png_ptr->row_buf + 1;
@@ -1629,7 +1639,8 @@ png_combine_row(png_structp png_ptr, png_bytep row,
}
shift = s_start;
for (i = 0; i < png_ptr->width; i++)
istop = png_ptr->width;
for (i = 0; i < istop; i++)
{
if (m & mask)
{
@@ -1658,7 +1669,7 @@ png_combine_row(png_structp png_ptr, png_bytep row,
png_bytep sp;
png_bytep dp;
png_size_t pixel_bytes;
png_uint_32 i;
png_uint_32 i, istop;
png_byte m;
pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
@@ -1666,7 +1677,8 @@ png_combine_row(png_structp png_ptr, png_bytep row,
sp = png_ptr->row_buf + 1;
dp = row;
m = 0x80;
for (i = 0; i < png_ptr->width; i++)
istop = png_ptr->width;
for (i = 0; i < istop; i++)
{
if (m & mask)
{
@@ -1708,7 +1720,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
int s_start, s_end, s_inc;
png_byte v;
png_uint_32 i;
int j;
int j, jstop;
sp = row + (png_size_t)((row_info->width - 1) >> 3);
dp = row + (png_size_t)((final_width - 1) >> 3);
@@ -1731,10 +1743,11 @@ 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);
for (j = 0; j < png_pass_inc[pass]; j++)
for (j = 0; j < jstop; j++)
{
*dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff);
*dp |= (png_byte)(v << dshift);
@@ -1762,6 +1775,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
int sshift, dshift;
int s_start, s_end, s_inc;
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);
@@ -1784,13 +1798,14 @@ 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;
int j;
v = (png_byte)((*sp >> sshift) & 0x3);
for (j = 0; j < png_pass_inc[pass]; j++)
for (j = 0; j < jstop; j++)
{
*dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff);
*dp |= (png_byte)(v << dshift);
@@ -1818,6 +1833,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
int sshift, dshift;
int s_start, s_end, s_inc;
png_uint_32 i;
int jstop;
sp = row + (png_size_t)((row_info->width - 1) >> 1);
dp = row + (png_size_t)((final_width - 1) >> 1);
@@ -1840,13 +1856,14 @@ 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;
int j;
v = (png_byte)((*sp >> sshift) & 0xf);
for (j = 0; j < png_pass_inc[pass]; j++)
for (j = 0; j < jstop; j++)
{
*dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);
*dp |= (png_byte)(v << dshift);
@@ -1872,19 +1889,21 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
{
png_bytep sp, dp;
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];
int j;
png_memcpy(v, sp, pixel_bytes);
for (j = 0; j < png_pass_inc[pass]; j++)
for (j = 0; j < jstop; j++)
{
png_memcpy(dp, v, pixel_bytes);
dp -= pixel_bytes;
@@ -1901,6 +1920,165 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
}
#endif
#ifndef PNG_READ_SLOW_FILTERING
void
png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
png_bytep prev_row, int filter)
{
png_debug(1, "in png_read_filter_row\n");
png_debug2(2,"row = %d, filter = %d\n", png_ptr->row_number, filter);
switch (filter)
{
case PNG_FILTER_VALUE_NONE:
break;
case PNG_FILTER_VALUE_SUB:
{
png_uint_32 i, istop;
int bpp;
png_bytep rp;
png_bytep lp;
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++)
{
*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;
istop = row_info->rowbytes;
for (i = 0, rp = row, pp = prev_row; i < istop; i++, rp++, pp++)
{
*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;
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++)
{
*rp = (png_byte)(((int)(*rp) +
((int)(*pp) / 2)) & 0xff);
}
istop = row_info->rowbytes;
for (lp = row; i < istop; i++, rp++,
lp++, pp++)
{
*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;
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++)
{
*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++)
{
int a, b, c, pa, pb, pc, p;
a = *lp;
b = *pp;
c = *cp;
p = a + b - c;
#ifdef PNG_USE_ABS
pa = abs(p - a);
pb = abs(p - b);
pc = abs(p - c);
#else
pa = p > a ? p - a : a - p;
pb = p > b ? p - b : b - p;
pc = p > c ? p - c : c - p;
#endif
/*
if (pa <= pb && pa <= pc)
p = a;
else if (pb <= pc)
p = b;
else
p = c;
*/
p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
*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:
png_error(png_ptr, "Bad adaptive filter type");
break;
}
}
#else /* PNG_READ_SLOW_FILTERING */
void
png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
png_bytep prev_row, int filter)
@@ -2010,6 +2188,7 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
break;
}
}
#endif /* PNG_READ_SLOW_FILTERING */
void
png_read_finish_row(png_structp png_ptr)
@@ -2186,8 +2365,20 @@ png_read_start_row(png_structp png_ptr)
#if defined(PNG_READ_FILLER_SUPPORTED)
if (png_ptr->transformations & (PNG_FILLER))
{
if (max_pixel_depth < 32)
max_pixel_depth = 32;
if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
{
if (max_pixel_depth <= 8)
max_pixel_depth = 16;
else
max_pixel_depth = 32;
}
else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
{
if (max_pixel_depth <= 32)
max_pixel_depth = 32;
else
max_pixel_depth = 64;
}
}
#endif
@@ -2216,7 +2407,7 @@ png_read_start_row(png_structp png_ptr)
for interlacing */
rowbytes = ((png_ptr->width + 7) & ~((png_uint_32)7));
/* calculate the maximum bytes needed, adding a byte and a pixel
for safety sake */
for safety's sake */
rowbytes = ((rowbytes * (png_uint_32)max_pixel_depth + 7) >> 3) +
1 + ((max_pixel_depth + 7) >> 3);
#ifdef PNG_MAX_MALLOC_64K