simplify decoding of coupling frequency range

Originally committed as revision 15809 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Justin Ruggles 2008-11-13 03:17:56 +00:00
parent 24834c1928
commit 6ee6d068f7

View File

@ -802,16 +802,18 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
/* coupling frequency range */
/* TODO: modify coupling end freq if spectral extension is used */
cpl_start_subband = get_bits(gbc, 4);
cpl_end_subband = get_bits(gbc, 4);
if (3 + cpl_end_subband - cpl_start_subband < 0) {
av_log(s->avctx, AV_LOG_ERROR, "3+cplendf = %d < cplbegf = %d\n", 3+cpl_end_subband, cpl_start_subband);
cpl_end_subband = get_bits(gbc, 4) + 3;
s->num_cpl_subbands = cpl_end_subband - cpl_start_subband;
if (s->num_cpl_subbands < 0) {
av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d > %d)\n",
cpl_start_subband, cpl_end_subband);
return -1;
}
s->num_cpl_bands = s->num_cpl_subbands = 3 + cpl_end_subband - cpl_start_subband;
s->start_freq[CPL_CH] = cpl_start_subband * 12 + 37;
s->end_freq[CPL_CH] = cpl_end_subband * 12 + 73;
s->end_freq[CPL_CH] = cpl_end_subband * 12 + 37;
/* coupling band structure */
s->num_cpl_bands = s->num_cpl_subbands;
if (!s->eac3 || get_bits1(gbc)) {
for (bnd = 0; bnd < s->num_cpl_subbands - 1; bnd++) {
s->cpl_band_struct[bnd] = get_bits1(gbc);