MrBesen/ffmpeg
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

ac3dec: fix processing of delta bit allocation information.

Browse Source 
The number of dba segments is the coded value + 1.
The coupling dba offset starts at the first coupling band, not at zero.
This commit is contained in:
Justin Ruggles 2011-04-17 12:26:47 -04:00
parent 0b05864eef
commit 4c64c8e95a
2 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
libavcodec/ac3.c
View File

@ -192,9 +192,9 @@ int ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *band_psd,
if (dba_mode == DBA_REUSE || dba_mode == DBA_NEW) {
int i, seg, delta;
if (dba_nsegs >= 8)
if (dba_nsegs > 8)
return -1;
band = 0;
band = band_start;
for (seg = 0; seg < dba_nsegs; seg++) {
band += dba_offsets[seg];
if (band >= AC3_CRITICAL_BANDS || dba_lengths[seg] > AC3_CRITICAL_BANDS-band)

4
libavcodec/ac3dec.c
View File

@ -1173,8 +1173,8 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
/* channel delta offset, len and bit allocation */
for (ch = !cpl_in_use; ch <= fbw_channels; ch++) {
if (s->dba_mode[ch] == DBA_NEW) {
s->dba_nsegs[ch] = get_bits(gbc, 3);
for (seg = 0; seg <= s->dba_nsegs[ch]; seg++) {
s->dba_nsegs[ch] = get_bits(gbc, 3) + 1;
for (seg = 0; seg < s->dba_nsegs[ch]; seg++) {
s->dba_offsets[ch][seg] = get_bits(gbc, 5);
s->dba_lengths[ch][seg] = get_bits(gbc, 4);
s->dba_values[ch][seg] = get_bits(gbc, 3);