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Imported from libpng-0.86.tar

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This commit is contained in:
Guy Schalnat
1996-01-10 02:56:49 -06:00
committed by Glenn Randers-Pehrson
parent 6d76471acd
commit 69b1448f19
21 changed files with 572 additions and 410 deletions
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63
pngrtran.c
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@@ -1,10 +1,10 @@
/* pngrtran.c - transforms the data in a row for png readers
libpng 1.0 beta 2 - version 0.85
libpng 1.0 beta 2 - version 0.86
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1995 Guy Eric Schalnat, Group 42, Inc.
December 19, 1995
Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
January 10, 1996
*/
#define PNG_INTERNAL
@@ -1168,7 +1168,8 @@ png_build_grayscale_palette(int bit_depth, png_colorp palette)
color_inc = 1;
break;
default:
num_palette = 0;
num_palette = 0;
color_inc = 0;
break;
}
@@ -1493,11 +1494,11 @@ png_do_background(png_row_infop row_info, png_bytep row,
else
{
v = gamma_16[
*(sp + 1) >> gamma_shift][*sp];
*(sp + 1) >> gamma_shift][*sp];
*sp = (v >> 8) & 0xff;
*(sp + 1) = v & 0xff;
}
}
}
}
else
#endif
@@ -2025,7 +2026,7 @@ png_do_background(png_row_infop row_info, png_bytep row,
you do this after you deal with the trasparency issue on grayscale
or rgb images. If your bit depth is 8, use gamma_table, if it is 16,
use gamma_16_table and gamma_shift. Build these with
build_gamma_table(). If your bit depth < 8, gamma correct a
build_gamma_table(). If your bit depth <= 8, gamma correct a
palette, not the data. */
void
png_do_gamma(png_row_infop row_info, png_bytep row,
@@ -2659,7 +2660,7 @@ png_build_gamma_table(png_structp png_ptr)
if ((int)png_ptr->sig_bit.green > sig_bit)
sig_bit = png_ptr->sig_bit.green;
if ((int)png_ptr->sig_bit.blue > sig_bit)
sig_bit = png_ptr->sig_bit.blue;
sig_bit = png_ptr->sig_bit.blue;
}
else
{
@@ -2691,17 +2692,17 @@ png_build_gamma_table(png_structp png_ptr)
png_ptr->gamma_16_table = (png_uint_16pp)png_malloc(png_ptr,
num * sizeof (png_uint_16p ));
if ((png_ptr->transformations & PNG_16_TO_8) &&
!(png_ptr->transformations & PNG_BACKGROUND))
{
if ((png_ptr->transformations & PNG_16_TO_8) &&
!(png_ptr->transformations & PNG_BACKGROUND))
{
double fin, fout;
png_uint_32 last, max;
for (i = 0; i < num; i++)
{
png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
for (i = 0; i < num; i++)
{
png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
256 * sizeof (png_uint_16));
}
}
g = 1.0 / g;
last = 0;
@@ -2709,33 +2710,33 @@ png_build_gamma_table(png_structp png_ptr)
{
fout = ((double)i + 0.5) / 256.0;
fin = pow(fout, g);
max = (png_uint_32)(fin * (double)(num << 8));
max = (png_uint_32)(fin * (double)((png_uint_32)num << 8));
while (last <= max)
{
png_ptr->gamma_16_table[(int)(last & 0xff) >> shift]
png_ptr->gamma_16_table[(int)(last & (0xff >> shift))]
[(int)(last >> (8 - shift))] =
(png_uint_16)i | ((png_uint_16)i << 8);
last++;
}
}
last++;
}
}
while (last < ((png_uint_32)num << 8))
{
png_ptr->gamma_16_table[(int)(last & 0xff) >> shift]
[(int)(last >> (8 - shift))] =
png_ptr->gamma_16_table[(int)(last & (0xff >> shift))]
[(int)(last >> (8 - shift))] =
(png_uint_16)65535L;
last++;
}
}
else
{
for (i = 0; i < num; i++)
{
png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
256 * sizeof (png_uint_16));
else
{
for (i = 0; i < num; i++)
{
png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
256 * sizeof (png_uint_16));
ig = (((png_uint_32)i *
(png_uint_32)png_gamma_shift[shift]) >> 4);
for (j = 0; j < 256; j++)
ig = (((png_uint_32)i *
(png_uint_32)png_gamma_shift[shift]) >> 4);
for (j = 0; j < 256; j++)
{
png_ptr->gamma_16_table[i][j] =
(png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) /