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Merge commit 'f0ccc65bc9ab9ddf1366066395564c71bcc825ee'

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* commit 'f0ccc65bc9ab9ddf1366066395564c71bcc825ee':
  ac3dec: Split coupling-specific code from decode_audio_block()

Merged-by: Clément Bœsch <u@pkh.me>
pull/244/merge
Clément Bœsch 8 years ago
parent 7c4dbd1df9 f0ccc65bc9
commit 2e3221c303
1 changed files with 116 additions and 91 deletions
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  1. 207
      libavcodec/ac3dec.c

207
libavcodec/ac3dec.c
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@ -935,6 +935,118 @@ static inline void spx_coordinates(AC3DecodeContext *s)
}
}
static inline int coupling_strategy(AC3DecodeContext *s, int blk,
uint8_t *bit_alloc_stages)
{
GetBitContext *bc = &s->gbc;
int fbw_channels = s->fbw_channels;
int channel_mode = s->channel_mode;
int ch;
memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
if (!s->eac3)
s->cpl_in_use[blk] = get_bits1(bc);
if (s->cpl_in_use[blk]) {
/* coupling in use */
int cpl_start_subband, cpl_end_subband;
if (channel_mode < AC3_CHMODE_STEREO) {
av_log(s->avctx, AV_LOG_ERROR, "coupling not allowed in mono or dual-mono\n");
return AVERROR_INVALIDDATA;
}
/* check for enhanced coupling */
if (s->eac3 && get_bits1(bc)) {
/* TODO: parse enhanced coupling strategy info */
avpriv_request_sample(s->avctx, "Enhanced coupling");
return AVERROR_PATCHWELCOME;
}
/* determine which channels are coupled */
if (s->eac3 && s->channel_mode == AC3_CHMODE_STEREO) {
s->channel_in_cpl[1] = 1;
s->channel_in_cpl[2] = 1;
} else {
for (ch = 1; ch <= fbw_channels; ch++)
s->channel_in_cpl[ch] = get_bits1(bc);
}
/* phase flags in use */
if (channel_mode == AC3_CHMODE_STEREO)
s->phase_flags_in_use = get_bits1(bc);
/* coupling frequency range */
cpl_start_subband = get_bits(bc, 4);
cpl_end_subband = s->spx_in_use ? (s->spx_src_start_freq - 37) / 12 :
get_bits(bc, 4) + 3;
if (cpl_start_subband >= cpl_end_subband) {
av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d >= %d)\n",
cpl_start_subband, cpl_end_subband);
return AVERROR_INVALIDDATA;
}
s->start_freq[CPL_CH] = cpl_start_subband * 12 + 37;
s->end_freq[CPL_CH] = cpl_end_subband * 12 + 37;
decode_band_structure(bc, blk, s->eac3, 0, cpl_start_subband,
cpl_end_subband,
ff_eac3_default_cpl_band_struct,
&s->num_cpl_bands, s->cpl_band_sizes);
} else {
/* coupling not in use */
for (ch = 1; ch <= fbw_channels; ch++) {
s->channel_in_cpl[ch] = 0;
s->first_cpl_coords[ch] = 1;
}
s->first_cpl_leak = s->eac3;
s->phase_flags_in_use = 0;
}
return 0;
}
static inline int coupling_coordinates(AC3DecodeContext *s, int blk)
{
GetBitContext *bc = &s->gbc;
int fbw_channels = s->fbw_channels;
int ch, bnd;
int cpl_coords_exist = 0;
for (ch = 1; ch <= fbw_channels; ch++) {
if (s->channel_in_cpl[ch]) {
if ((s->eac3 && s->first_cpl_coords[ch]) || get_bits1(bc)) {
int master_cpl_coord, cpl_coord_exp, cpl_coord_mant;
s->first_cpl_coords[ch] = 0;
cpl_coords_exist = 1;
master_cpl_coord = 3 * get_bits(bc, 2);
for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
cpl_coord_exp = get_bits(bc, 4);
cpl_coord_mant = get_bits(bc, 4);
if (cpl_coord_exp == 15)
s->cpl_coords[ch][bnd] = cpl_coord_mant << 22;
else
s->cpl_coords[ch][bnd] = (cpl_coord_mant + 16) << 21;
s->cpl_coords[ch][bnd] >>= (cpl_coord_exp + master_cpl_coord);
}
} else if (!blk) {
av_log(s->avctx, AV_LOG_ERROR, "new coupling coordinates must "
"be present in block 0\n");
return AVERROR_INVALIDDATA;
}
} else {
/* channel not in coupling */
s->first_cpl_coords[ch] = 1;
}
}
/* phase flags */
if (s->channel_mode == AC3_CHMODE_STEREO && cpl_coords_exist) {
for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
s->phase_flags[bnd] = s->phase_flags_in_use ? get_bits1(bc) : 0;
}
}
return 0;
}
/**
* Decode a single audio block from the AC-3 bitstream.
*/
@ -1005,63 +1117,8 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
/* coupling strategy */
if (s->eac3 ? s->cpl_strategy_exists[blk] : get_bits1(gbc)) {
memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
if (!s->eac3)
s->cpl_in_use[blk] = get_bits1(gbc);
if (s->cpl_in_use[blk]) {
/* coupling in use */
int cpl_start_subband, cpl_end_subband;
if (channel_mode < AC3_CHMODE_STEREO) {
av_log(s->avctx, AV_LOG_ERROR, "coupling not allowed in mono or dual-mono\n");
return AVERROR_INVALIDDATA;
}
/* check for enhanced coupling */
if (s->eac3 && get_bits1(gbc)) {
/* TODO: parse enhanced coupling strategy info */
avpriv_request_sample(s->avctx, "Enhanced coupling");
return AVERROR_PATCHWELCOME;
}
/* determine which channels are coupled */
if (s->eac3 && s->channel_mode == AC3_CHMODE_STEREO) {
s->channel_in_cpl[1] = 1;
s->channel_in_cpl[2] = 1;
} else {
for (ch = 1; ch <= fbw_channels; ch++)
s->channel_in_cpl[ch] = get_bits1(gbc);
}
/* phase flags in use */
if (channel_mode == AC3_CHMODE_STEREO)
s->phase_flags_in_use = get_bits1(gbc);
/* coupling frequency range */
cpl_start_subband = get_bits(gbc, 4);
cpl_end_subband = s->spx_in_use ? (s->spx_src_start_freq - 37) / 12 :
get_bits(gbc, 4) + 3;
if (cpl_start_subband >= cpl_end_subband) {
av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d >= %d)\n",
cpl_start_subband, cpl_end_subband);
return AVERROR_INVALIDDATA;
}
s->start_freq[CPL_CH] = cpl_start_subband * 12 + 37;
s->end_freq[CPL_CH] = cpl_end_subband * 12 + 37;
decode_band_structure(gbc, blk, s->eac3, 0, cpl_start_subband,
cpl_end_subband,
ff_eac3_default_cpl_band_struct,
&s->num_cpl_bands, s->cpl_band_sizes);
} else {
/* coupling not in use */
for (ch = 1; ch <= fbw_channels; ch++) {
s->channel_in_cpl[ch] = 0;
s->first_cpl_coords[ch] = 1;
}
s->first_cpl_leak = s->eac3;
s->phase_flags_in_use = 0;
}
if ((ret = coupling_strategy(s, blk, bit_alloc_stages)) < 0)
return ret;
} else if (!s->eac3) {
if (!blk) {
av_log(s->avctx, AV_LOG_ERROR, "new coupling strategy must "
@ -1075,40 +1132,8 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
/* coupling coordinates */
if (cpl_in_use) {
int cpl_coords_exist = 0;
for (ch = 1; ch <= fbw_channels; ch++) {
if (s->channel_in_cpl[ch]) {
if ((s->eac3 && s->first_cpl_coords[ch]) || get_bits1(gbc)) {
int master_cpl_coord, cpl_coord_exp, cpl_coord_mant;
s->first_cpl_coords[ch] = 0;
cpl_coords_exist = 1;
master_cpl_coord = 3 * get_bits(gbc, 2);
for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
cpl_coord_exp = get_bits(gbc, 4);
cpl_coord_mant = get_bits(gbc, 4);
if (cpl_coord_exp == 15)
s->cpl_coords[ch][bnd] = cpl_coord_mant << 22;
else
s->cpl_coords[ch][bnd] = (cpl_coord_mant + 16) << 21;
s->cpl_coords[ch][bnd] >>= (cpl_coord_exp + master_cpl_coord);
}
} else if (!blk) {
av_log(s->avctx, AV_LOG_ERROR, "new coupling coordinates must "
"be present in block 0\n");
return AVERROR_INVALIDDATA;
}
} else {
/* channel not in coupling */
s->first_cpl_coords[ch] = 1;
}
}
/* phase flags */
if (channel_mode == AC3_CHMODE_STEREO && cpl_coords_exist) {
for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
s->phase_flags[bnd] = s->phase_flags_in_use? get_bits1(gbc) : 0;
}
}
if ((ret = coupling_coordinates(s, blk)) < 0)
return ret;
}
/* stereo rematrixing strategy and band structure */

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