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Imported from libpng-0.96.tar

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This commit is contained in:
Andreas Dilger
1997-05-16 02:46:07 -05:00
committed by Glenn Randers-Pehrson
parent 02ad0efbc8
commit 47a0c422ca
40 changed files with 6833 additions and 3520 deletions
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195
pngwtran.c
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@@ -1,10 +1,11 @@
/* pngwtran.c - transforms the data in a row for png writers
/* pngwtran.c - transforms the data in a row for PNG writers
libpng 1.0 beta 4 - version 0.90
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.
January 10, 1997
Copyright (c) 1996, 1997 Andreas Dilger
May 12, 1997
*/
#define PNG_INTERNAL
@@ -15,15 +16,16 @@
void
png_do_write_transformations(png_structp png_ptr)
{
png_debug(1, "in png_do_write_transformations\n");
#if defined(PNG_WRITE_FILLER_SUPPORTED)
if (png_ptr->transformations & PNG_FILLER)
png_do_write_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
png_ptr->flags);
#endif
#if defined(PNG_WRITE_PACK_SUPPORTED)
if (png_ptr->transformations & PNG_PACK)
png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1,
png_ptr->bit_depth);
(png_uint_32)png_ptr->bit_depth);
#endif
#if defined(PNG_WRITE_SHIFT_SUPPORTED)
if (png_ptr->transformations & PNG_SHIFT)
@@ -34,6 +36,10 @@ png_do_write_transformations(png_structp png_ptr)
if (png_ptr->transformations & PNG_SWAP_BYTES)
png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
#endif
#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
if (png_ptr->transformations & PNG_SWAP_ALPHA)
png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
#endif
#if defined(PNG_WRITE_BGR_SUPPORTED)
if (png_ptr->transformations & PNG_BGR)
png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
@@ -49,20 +55,22 @@ png_do_write_transformations(png_structp png_ptr)
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_byte bit_depth)
png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
{
if (row_info && row && row_info->bit_depth == 8 &&
png_debug(1, "in png_do_pack\n");
if (row_info->bit_depth == 8 &&
#if defined(PNG_USELESS_TESTS_SUPPORTED)
row != NULL && row_info != NULL &&
#endif
row_info->channels == 1)
{
switch (bit_depth)
switch ((int)bit_depth)
{
case 1:
{
png_bytep sp;
png_bytep dp;
int mask;
png_int_32 i;
int v;
png_bytep sp, dp;
int mask, v;
png_uint_32 i;
sp = row;
dp = row;
@@ -70,7 +78,7 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
v = 0;
for (i = 0; i < row_info->width; i++)
{
if (*sp)
if (*sp != 0)
v |= mask;
sp++;
if (mask > 1)
@@ -89,12 +97,9 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
}
case 2:
{
png_bytep sp;
png_bytep dp;
int shift;
png_int_32 i;
int v;
png_byte value;
png_bytep sp, dp;
int shift, v;
png_uint_32 i;
sp = row;
dp = row;
@@ -102,6 +107,8 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
v = 0;
for (i = 0; i < row_info->width; i++)
{
png_byte value;
value = (png_byte)(*sp & 0x3);
v |= (value << shift);
if (shift == 0)
@@ -121,12 +128,9 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
}
case 4:
{
png_bytep sp;
png_bytep dp;
int shift;
png_int_32 i;
int v;
png_byte value;
png_bytep sp, dp;
int shift, v;
png_uint_32 i;
sp = row;
dp = row;
@@ -134,6 +138,8 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
v = 0;
for (i = 0; i < row_info->width; i++)
{
png_byte value;
value = (png_byte)(*sp & 0xf);
v |= (value << shift);
@@ -154,8 +160,8 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
break;
}
}
row_info->bit_depth = bit_depth;
row_info->pixel_depth = (png_uint_16)(bit_depth * row_info->channels);
row_info->bit_depth = (png_byte)bit_depth;
row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels);
row_info->rowbytes =
((row_info->width * row_info->pixel_depth + 7) >> 3);
}
@@ -172,11 +178,16 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
void
png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
{
if (row && row_info &&
png_debug(1, "in png_do_shift\n");
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if (row != NULL && row_info != NULL &&
#else
if (
#endif
row_info->color_type != PNG_COLOR_TYPE_PALETTE)
{
int shift_start[4], shift_dec[4];
int channels;
png_uint_32 channels;
channels = 0;
if (row_info->color_type & PNG_COLOR_MASK_COLOR)
@@ -209,7 +220,6 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
{
png_bytep bp;
png_uint_32 i;
int j;
png_byte mask;
if (bit_depth->gray == 1 && row_info->bit_depth == 2)
@@ -221,7 +231,8 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
for (bp = row, i = 0; i < row_info->rowbytes; i++, bp++)
{
int v;
png_uint_16 v;
int j;
v = *bp;
*bp = 0;
@@ -238,7 +249,6 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
{
png_bytep bp;
png_uint_32 i;
int j;
for (bp = row, i = 0; i < row_info->width; i++)
{
@@ -246,7 +256,8 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
for (c = 0; c < channels; c++, bp++)
{
int v;
png_uint_16 v;
int j;
v = *bp;
*bp = 0;
@@ -264,20 +275,17 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
{
png_bytep bp;
png_uint_32 i;
int j;
for (bp = row, i = 0;
i < row_info->width * row_info->channels;
i++)
for (bp = row, i = 0; i < row_info->width * row_info->channels; i++)
{
int c;
for (c = 0; c < channels; c++, bp += 2)
{
png_uint_16 value, v;
int j;
v = (png_uint_16)(((png_uint_16)(*bp) << 8) +
(png_uint_16)(*(bp + 1)));
v = ((png_uint_16)(*bp) << 8) + *(bp + 1);
value = 0;
for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
{
@@ -295,51 +303,88 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
}
#endif
#ifdef PNG_WRITE_FILLER_SUPPORTED
/* remove filler byte */
#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
void
png_do_write_filler(png_row_infop row_info, png_bytep row,
png_uint_32 flags)
png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
{
if (row && row_info && row_info->color_type == PNG_COLOR_TYPE_RGB &&
row_info->bit_depth == 8)
png_debug(1, "in png_do_write_swap_alpha\n");
#if defined(PNG_USELESS_TESTS_SUPPORTED)
if (row != NULL && row_info != NULL)
#endif
{
if (flags & PNG_FLAG_FILLER_AFTER)
if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
{
png_bytep sp, dp;
png_uint_32 i;
for (i = 1, sp = row + 4, dp = row + 3;
i < row_info->width;
i++)
/* This converts from ARGB to RGBA */
if (row_info->bit_depth == 8)
{
*dp++ = *sp++;
*dp++ = *sp++;
*dp++ = *sp++;
sp++;
png_bytep sp, dp;
png_byte save;
png_uint_32 i;
for (i = 0, sp = dp = row; i < row_info->width; i++)
{
save = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = save;
}
}
/* This converts from AARRGGBB to RRGGBBAA */
else
{
png_bytep sp, dp;
png_byte save[2];
png_uint_32 i;
for (i = 0, sp = dp = row; i < row_info->width; i++)
{
save[0] = *(sp++);
save[1] = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = save[0];
*(dp++) = save[1];
}
}
row_info->channels = 3;
row_info->pixel_depth = 24;
row_info->rowbytes = row_info->width * 3;
}
else
else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
{
png_bytep sp, dp;
png_uint_32 i;
for (i = 0, sp = row, dp = row;
i < row_info->width;
i++)
/* This converts from AG to GA */
if (row_info->bit_depth == 8)
{
sp++;
*dp++ = *sp++;
*dp++ = *sp++;
*dp++ = *sp++;
png_bytep sp, dp;
png_byte save;
png_uint_32 i;
for (i = 0, sp = dp = row; i < row_info->width; i++)
{
save = *(sp++);
*(dp++) = *(sp++);
*(dp++) = save;
}
}
/* This converts from AAGG to GGAA */
else
{
png_bytep sp, dp;
png_byte save[2];
png_uint_32 i;
for (i = 0, sp = dp = row; i < row_info->width; i++)
{
save[0] = *(sp++);
save[1] = *(sp++);
*(dp++) = *(sp++);
*(dp++) = *(sp++);
*(dp++) = save[0];
*(dp++) = save[1];
}
}
row_info->channels = 3;
row_info->pixel_depth = 24;
row_info->rowbytes = row_info->width * 3;
}
}
}