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[libpng16] Bookkeeping: Moved functions around (no changes). Moved transform

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function definitions before the place where they are called so that
they can be masde static. Move the intrapixel functions and the
grayscale palette builder out of the png?tran.c files. The latter
isn't a transform function and is no longer used internally, and the
former MNG specific functions are better placed in pngread/pngwrite.c
This commit is contained in:
John Bowler
2013-12-19 15:24:06 -06:00
committed by Glenn Randers-Pehrson
parent bff81bdddc
commit c10930a4fc
9 changed files with 549 additions and 543 deletions
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67
pngread.c
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@@ -305,6 +305,72 @@ png_start_read_image(png_structrp png_ptr)
#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
#ifdef PNG_MNG_FEATURES_SUPPORTED
/* Undoes intrapixel differencing,
* NOTE: this is apparently only supported in the 'sequential' reader.
*/
static void
png_do_read_intrapixel(png_row_infop row_info, png_bytep row)
{
png_debug(1, "in png_do_read_intrapixel");
if (
(row_info->color_type & PNG_COLOR_MASK_COLOR))
{
int bytes_per_pixel;
png_uint_32 row_width = row_info->width;
if (row_info->bit_depth == 8)
{
png_bytep rp;
png_uint_32 i;
if (row_info->color_type == PNG_COLOR_TYPE_RGB)
bytes_per_pixel = 3;
else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
bytes_per_pixel = 4;
else
return;
for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
{
*(rp) = (png_byte)((256 + *rp + *(rp + 1)) & 0xff);
*(rp+2) = (png_byte)((256 + *(rp + 2) + *(rp + 1)) & 0xff);
}
}
else if (row_info->bit_depth == 16)
{
png_bytep rp;
png_uint_32 i;
if (row_info->color_type == PNG_COLOR_TYPE_RGB)
bytes_per_pixel = 6;
else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
bytes_per_pixel = 8;
else
return;
for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
{
png_uint_32 s0 = (*(rp ) << 8) | *(rp + 1);
png_uint_32 s1 = (*(rp + 2) << 8) | *(rp + 3);
png_uint_32 s2 = (*(rp + 4) << 8) | *(rp + 5);
png_uint_32 red = (s0 + s1 + 65536) & 0xffff;
png_uint_32 blue = (s2 + s1 + 65536) & 0xffff;
*(rp ) = (png_byte)((red >> 8) & 0xff);
*(rp + 1) = (png_byte)(red & 0xff);
*(rp + 4) = (png_byte)((blue >> 8) & 0xff);
*(rp + 5) = (png_byte)(blue & 0xff);
}
}
}
}
#endif /* PNG_MNG_FEATURES_SUPPORTED */
void PNGAPI
png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
{
@@ -489,7 +555,6 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
}
#endif
#ifdef PNG_READ_TRANSFORMS_SUPPORTED
if (png_ptr->transformations)
png_do_read_transformations(png_ptr, &row_info);