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The Independent JPEG Group's JPEG software v8d

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This commit is contained in:
Guido Vollbeding
2012-01-15 00:00:00 +00:00
committed by DRC
parent c39ec149e8
commit 5829cb2398
40 changed files with 1437 additions and 734 deletions
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20
jdarith.c
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@@ -1,7 +1,7 @@
/*
* jdarith.c
*
* Developed 1997-2009 by Guido Vollbeding.
* Developed 1997-2011 by Guido Vollbeding.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
@@ -145,7 +145,7 @@ arith_decode (j_decompress_ptr cinfo, unsigned char *st)
e->a <<= 1;
}
/* Fetch values from our compact representation of Table D.2:
/* Fetch values from our compact representation of Table D.3(D.2):
* Qe values and probability estimation state machine
*/
sv = *st;
@@ -575,15 +575,19 @@ decode_mcu (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
/* Sections F.2.4.2 & F.1.4.4.2: Decoding of AC coefficients */
if (cinfo->lim_Se == 0) continue;
tbl = compptr->ac_tbl_no;
k = 0;
/* Figure F.20: Decode_AC_coefficients */
for (k = 1; k <= cinfo->lim_Se; k++) {
st = entropy->ac_stats[tbl] + 3 * (k - 1);
do {
st = entropy->ac_stats[tbl] + 3 * k;
if (arith_decode(cinfo, st)) break; /* EOB flag */
while (arith_decode(cinfo, st + 1) == 0) {
st += 3; k++;
if (k > cinfo->lim_Se) {
for (;;) {
k++;
if (arith_decode(cinfo, st + 1)) break;
st += 3;
if (k >= cinfo->lim_Se) {
WARNMS(cinfo, JWRN_ARITH_BAD_CODE);
entropy->ct = -1; /* spectral overflow */
return TRUE;
@@ -616,7 +620,7 @@ decode_mcu (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)
if (arith_decode(cinfo, st)) v |= m;
v += 1; if (sign) v = -v;
(*block)[natural_order[k]] = (JCOEF) v;
}
} while (k < cinfo->lim_Se);
}
return TRUE;