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Imported from pngcrush-1.3.5.tar

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This commit is contained in:
Glenn Randers-Pehrson
2000-02-19 14:58:52 -06:00
parent f142567725
commit 601daa7a76
28 changed files with 971 additions and 518 deletions
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21
pngrtran.c
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@@ -1,7 +1,7 @@
/* pngrtran.c - transforms the data in a row for PNG readers
*
* libpng 1.0.5m - January 7, 2000
* libpng 1.0.5s - February 18, 2000
* 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
@@ -658,7 +658,8 @@ png_init_read_transformations(png_structp png_ptr)
#endif
#if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED)
if (png_ptr->transformations & PNG_BACKGROUND_EXPAND)
if ((png_ptr->transformations & PNG_BACKGROUND_EXPAND) &&
(png_ptr->transformations & PNG_EXPAND))
{
if (!(color_type & PNG_COLOR_MASK_COLOR)) /* i.e., GRAY or GRAY_ALPHA */
{
@@ -1674,9 +1675,15 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
for (i = 0; i < row_width; i++)
{
*(--dp) = (png_byte)(255 - *(--sp));
/* This does nothing:
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
We can replace it with:
*/
sp-=3;
dp=sp;
}
}
/* This inverts the alpha channel in RRGGBBAA */
@@ -1690,12 +1697,18 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
{
*(--dp) = (png_byte)(255 - *(--sp));
*(--dp) = (png_byte)(255 - *(--sp));
/* This does nothing:
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*(--dp) = *(--sp);
We can replace it with:
*/
sp-=6;
dp=sp;
}
}
}
@@ -1725,8 +1738,12 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
{
*(--dp) = (png_byte)(255 - *(--sp));
*(--dp) = (png_byte)(255 - *(--sp));
/*
*(--dp) = *(--sp);
*(--dp) = *(--sp);
*/
sp-=2;
dp=sp;
}
}
}