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Merge remote-tracking branch 'local/libpng17' into libpng17

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This commit is contained in:
John Bowler 2015-09-26 15:17:27 -07:00
commit 8dfa93beed
2 changed files with 15 additions and 5 deletions
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1
contrib/pngminim/decoder/pngusr.dfa
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@ -36,6 +36,7 @@ option FLOATING_ARITHMETIC off
option SETJMP on
option STDIO on
option READ_EXPAND on
option READ_IMAGE on
option READ_DEINTERLACE on
option READ_STRIP_16_TO_8 on
option USER_LIMITS on

19
pngrtran.c
View File

@ -867,10 +867,12 @@ png_do_expand_lbd_gray(png_transformp *transform, png_transform_controlp tc)
const png_const_bytep ep = dp;
png_const_bytep sp = png_voidcast(png_const_bytep, tc->sp);
const unsigned int bit_depth = tc->bit_depth;
# ifdef PNG_READ_sBIT_SUPPORTED
unsigned int insignificant_bits = 0U;
# endif /* READ_sBIT */
# ifdef PNG_READ_tRNS_SUPPORTED
unsigned int gray = 0xffffU; /* doesn't match anything */
unsigned int do_alpha = 0U;
unsigned int gray = 0xffffU; /* doesn't match anything */
unsigned int do_alpha = 0U;
# endif /* READ_tRNS */
sp += PNG_TC_ROWBYTES(*tc); /* last byte +1 */
@ -941,6 +943,7 @@ png_do_expand_lbd_gray(png_transformp *transform, png_transform_controlp tc)
check_tRNS
# ifdef PNG_READ_sBIT_SUPPORTED
/* 'sig_bits' must be 1 or 2 leaving insignificant_bits 0 or
* 1. This may look silly but it allows a compact representation
* of 1 bit gray + 1 bit alpha (transparency):
@ -952,6 +955,7 @@ png_do_expand_lbd_gray(png_transformp *transform, png_transform_controlp tc)
}
else
# endif
*--dp = PNG_BYTE(pixel * 85U);
if (dp <= ep) break;
@ -967,7 +971,9 @@ png_do_expand_lbd_gray(png_transformp *transform, png_transform_controlp tc)
{
unsigned int shift = 7U & -(tc->width << 2)/*overflow ok*/;
unsigned int s = *--sp;
# ifdef PNG_READ_sBIT_SUPPORTED
const unsigned int div = (1U << (4U-insignificant_bits)) - 1U;
# endif
for (;;)
{
@ -977,9 +983,11 @@ png_do_expand_lbd_gray(png_transformp *transform, png_transform_controlp tc)
check_tRNS
/* insignifcant_bits may be 0, 1, 2 or 3, requiring a multiply by
* 17, 255/7, 85 or 255. Since this operation is always cached
* we don't much care about the time to do the divide below.
# ifdef PNG_READ_sBIT_SUPPORTED
/* insignificant_bits may be 0, 1, 2 or 3, requiring a multiply
* by 17, 255/7, 85 or 255. Since this operation is always
* cached we don't much care about the time to do the divide
* below.
*/
if (insignificant_bits)
{
@ -988,6 +996,7 @@ png_do_expand_lbd_gray(png_transformp *transform, png_transform_controlp tc)
}
else
# endif
pixel *= 17U;
*--dp = PNG_BYTE(pixel);