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[libpng16] Imported from libpng-1.6.0beta05.tar

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Glenn Randers-Pehrson
2012-02-02 23:11:45 -06:00
parent 96cf4bde0e
commit f3af706c2a
186 changed files with 8544 additions and 20666 deletions
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198
pngtrans.c
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@@ -1,8 +1,8 @@
/* pngtrans.c - transforms the data in a row (used by both readers and writers)
*
* Last changed in libpng 1.6.0 [February 14, 2013]
* Copyright (c) 1998-2013 Glenn Randers-Pehrson
* Last changed in libpng 1.6.0 [(PENDING RELEASE)]
* Copyright (c) 1998-2012 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
*
@@ -122,79 +122,32 @@ png_set_filler(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
if (png_ptr == NULL)
return;
/* In libpng 1.6 it is possible to determine whether this is a read or write
* operation and therefore to do more checking here for a valid call.
*/
if (png_ptr->mode & PNG_IS_READ_STRUCT)
{
# ifdef PNG_READ_FILLER_SUPPORTED
/* On read png_set_filler is always valid, regardless of the base PNG
* format, because other transformations can give a format where the
* filler code can execute (basically an 8 or 16-bit component RGB or G
* format.)
*
* NOTE: usr_channels is not used by the read code! (This has led to
* confusion in the past.) The filler is only used in the read code.
*/
png_ptr->filler = (png_uint_16)filler;
# else
png_app_error(png_ptr, "png_set_filler not supported on read");
PNG_UNUSED(filler) /* not used in the write case */
return;
# endif
}
else /* write */
{
# ifdef PNG_WRITE_FILLER_SUPPORTED
/* On write the usr_channels parameter must be set correctly at the
* start to record the number of channels in the app-supplied data.
*/
switch (png_ptr->color_type)
{
case PNG_COLOR_TYPE_RGB:
png_ptr->usr_channels = 4;
break;
case PNG_COLOR_TYPE_GRAY:
if (png_ptr->bit_depth >= 8)
{
png_ptr->usr_channels = 2;
break;
}
else
{
/* There simply isn't any code in libpng to strip out bits
* from bytes when the components are less than a byte in
* size!
*/
png_app_error(png_ptr,
"png_set_filler is invalid for low bit depth gray output");
return;
}
default:
png_app_error(png_ptr,
"png_set_filler: inappropriate color type");
return;
}
# else
png_app_error(png_ptr, "png_set_filler not supported on write");
return;
# endif
}
/* Here on success - libpng supports the operation, set the transformation
* and the flag to say where the filler channel is.
*/
png_ptr->transformations |= PNG_FILLER;
png_ptr->filler = (png_uint_16)filler;
if (filler_loc == PNG_FILLER_AFTER)
png_ptr->flags |= PNG_FLAG_FILLER_AFTER;
else
png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER;
/* This should probably go in the "do_read_filler" routine.
* I attempted to do that in libpng-1.0.1a but that caused problems
* so I restored it in libpng-1.0.2a
*/
if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
{
png_ptr->usr_channels = 4;
}
/* Also I added this in libpng-1.0.2a (what happens when we expand
* a less-than-8-bit grayscale to GA?) */
if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8)
{
png_ptr->usr_channels = 2;
}
}
/* Added to libpng-1.2.7 */
@@ -207,9 +160,7 @@ png_set_add_alpha(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
return;
png_set_filler(png_ptr, filler, filler_loc);
/* The above may fail to do anything. */
if (png_ptr->transformations & PNG_FILLER)
png_ptr->transformations |= PNG_ADD_ALPHA;
png_ptr->transformations |= PNG_ADD_ALPHA;
}
#endif
@@ -668,109 +619,6 @@ png_do_bgr(png_row_infop row_info, png_bytep row)
}
#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
/* Added at libpng-1.5.10 */
void /* PRIVATE */
png_do_check_palette_indexes(png_structrp png_ptr, png_row_infop row_info)
{
if (png_ptr->num_palette < (1 << row_info->bit_depth) &&
png_ptr->num_palette > 0) /* num_palette can be 0 in MNG files */
{
/* Calculations moved outside switch in an attempt to stop different
* compiler warnings. 'padding' is in *bits* within the last byte, it is
* an 'int' because pixel_depth becomes an 'int' in the expression below,
* and this calculation is used because it avoids warnings that other
* forms produced on either GCC or MSVC.
*/
int padding = (-row_info->pixel_depth * row_info->width) & 7;
png_bytep rp = png_ptr->row_buf + row_info->rowbytes;
switch (row_info->bit_depth)
{
case 1:
{
/* in this case, all bytes must be 0 so we don't need
* to unpack the pixels except for the rightmost one.
*/
for (; rp > png_ptr->row_buf; rp--)
{
if (*rp >> padding != 0)
png_ptr->num_palette_max = 1;
padding = 0;
}
break;
}
case 2:
{
for (; rp > png_ptr->row_buf; rp--)
{
int i = ((*rp >> padding) & 0x03);
if (i > png_ptr->num_palette_max)
png_ptr->num_palette_max = i;
i = (((*rp >> padding) >> 2) & 0x03);
if (i > png_ptr->num_palette_max)
png_ptr->num_palette_max = i;
i = (((*rp >> padding) >> 4) & 0x03);
if (i > png_ptr->num_palette_max)
png_ptr->num_palette_max = i;
i = (((*rp >> padding) >> 6) & 0x03);
if (i > png_ptr->num_palette_max)
png_ptr->num_palette_max = i;
padding = 0;
}
break;
}
case 4:
{
for (; rp > png_ptr->row_buf; rp--)
{
int i = ((*rp >> padding) & 0x0f);
if (i > png_ptr->num_palette_max)
png_ptr->num_palette_max = i;
i = (((*rp >> padding) >> 4) & 0x0f);
if (i > png_ptr->num_palette_max)
png_ptr->num_palette_max = i;
padding = 0;
}
break;
}
case 8:
{
for (; rp > png_ptr->row_buf; rp--)
{
if (*rp > png_ptr->num_palette_max)
png_ptr->num_palette_max = (int) *rp;
}
break;
}
default:
break;
}
}
}
#endif /* PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED */
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
#ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED
@@ -800,7 +648,7 @@ png_get_user_transform_ptr(png_const_structrp png_ptr)
if (png_ptr == NULL)
return (NULL);
return png_ptr->user_transform_ptr;
return ((png_voidp)png_ptr->user_transform_ptr);
}
#endif