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add more OKed parts of the E-AC-3 decoder: structural changes to support AHT mode mantissa decoding

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Originally committed as revision 14989 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Justin Ruggles 2008-08-27 01:36:20 +00:00
parent 6a68105e2b
commit e43b29ab26
1 changed files with 7 additions and 7 deletions
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14
libavcodec/ac3dec.c
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@ -443,7 +443,7 @@ typedef struct {
* Get the transform coefficients for a particular channel
* reference: Section 7.3 Quantization and Decoding of Mantissas
*/
static void decode_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, mant_groups *m)
static void ac3_decode_transform_coeffs_ch(AC3DecodeContext *s, int ch_index, mant_groups *m)
{
GetBitContext *gbc = &s->gbc;
int i, gcode, tbap, start, end;
@ -548,7 +548,6 @@ static void remove_dithering(AC3DecodeContext *s) {
}
}
#if 0
static void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch,
mant_groups *m)
{
@ -558,19 +557,20 @@ static void decode_transform_coeffs_ch(AC3DecodeContext *s, int blk, int ch,
/* if AHT is used, mantissas for all blocks are encoded in the first
block of the frame. */
int bin;
/*
if (!blk)
ff_eac3_decode_transform_coeffs_aht_ch(s, ch);
*/
for (bin = s->start_freq[ch]; bin < s->end_freq[ch]; bin++) {
s->fixed_coeffs[ch][bin] = s->pre_mantissa[ch][bin][blk] >> s->dexps[ch][bin];
}
}
}
#endif
/**
* Get the transform coefficients.
*/
static void decode_transform_coeffs(AC3DecodeContext *s)
static void decode_transform_coeffs(AC3DecodeContext *s, int blk)
{
int ch, end;
int got_cplchan = 0;
@ -580,12 +580,12 @@ static void decode_transform_coeffs(AC3DecodeContext *s)
for (ch = 1; ch <= s->channels; ch++) {
/* transform coefficients for full-bandwidth channel */
decode_transform_coeffs_ch(s, ch, &m);
decode_transform_coeffs_ch(s, blk, ch, &m);
/* tranform coefficients for coupling channel come right after the
coefficients for the first coupled channel*/
if (s->channel_in_cpl[ch]) {
if (!got_cplchan) {
decode_transform_coeffs_ch(s, CPL_CH, &m);
decode_transform_coeffs_ch(s, blk, CPL_CH, &m);
calc_transform_coeffs_cpl(s);
got_cplchan = 1;
}
@ -1075,7 +1075,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
/* unpack the transform coefficients
this also uncouples channels if coupling is in use. */
decode_transform_coeffs(s);
decode_transform_coeffs(s, blk);
/* TODO: generate enhanced coupling coordinates and uncouple */