int avpriv_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr)
{
int frame_size_code;
memset(hdr, 0, sizeof(*hdr));
hdr->sync_word = get_bits(gbc, 16);
if(hdr->sync_word != 0x0B77)
return AAC_AC3_PARSE_ERROR_SYNC;
/* read ahead to bsid to distinguish between AC-3 and E-AC-3 */
hdr->bitstream_id = show_bits_long(gbc, 29) & 0x1F;
if(hdr->bitstream_id > 16)
return AAC_AC3_PARSE_ERROR_BSID;
hdr->num_blocks = 6;
/* set default mix levels */
hdr->center_mix_level = 5; // -4.5dB
hdr->surround_mix_level = 6; // -6.0dB
if(hdr->bitstream_id <= 10) {
/* Normal AC-3 */
hdr->crc1 = get_bits(gbc, 16);
hdr->sr_code = get_bits(gbc, 2);
if(hdr->sr_code == 3)
return AAC_AC3_PARSE_ERROR_SAMPLE_RATE;
frame_size_code = get_bits(gbc, 6);
if(frame_size_code > 37)
return AAC_AC3_PARSE_ERROR_FRAME_SIZE;
skip_bits(gbc, 5); // skip bsid, already got it
hdr->bitstream_mode = get_bits(gbc, 3);
hdr->channel_mode = get_bits(gbc, 3);
if(hdr->channel_mode == AC3_CHMODE_STEREO) {
skip_bits(gbc, 2); // skip dsurmod
} else {
if((hdr->channel_mode & 1) && hdr->channel_mode != AC3_CHMODE_MONO)
hdr-> center_mix_level = center_levels[get_bits(gbc, 2)];
if(hdr->channel_mode & 4)
hdr->surround_mix_level = surround_levels[get_bits(gbc, 2)];
}
hdr->lfe_on = get_bits1(gbc);
hdr->sr_shift = FFMAX(hdr->bitstream_id, 8) - 8;
hdr->sample_rate = ff_ac3_sample_rate_tab[hdr->sr_code] >> hdr->sr_shift;
hdr->bit_rate = (ff_ac3_bitrate_tab[frame_size_code>>1] * 1000) >> hdr->sr_shift;
hdr->channels = ff_ac3_channels_tab[hdr->channel_mode] + hdr->lfe_on;
hdr->frame_size = ff_ac3_frame_size_tab[frame_size_code][hdr->sr_code] * 2;
hdr->frame_type = EAC3_FRAME_TYPE_AC3_CONVERT; //EAC3_FRAME_TYPE_INDEPENDENT;
hdr->substreamid = 0;
} else {
int ff_ac3_parse_header(const uint8_t buf[7], AC3HeaderInfo *hdr)
{
GetBitContext gbc;
int frame_size_code;
int num_blocks;
memset(hdr, 0, sizeof(*hdr));
init_get_bits(&gbc, buf, 54);
hdr->sync_word = get_bits(&gbc, 16);
if(hdr->sync_word != 0x0B77)
return AC3_PARSE_ERROR_SYNC;
/* read ahead to bsid to distinguish between AC-3 and E-AC-3 */
hdr->bitstream_id = show_bits_long(&gbc, 29) & 0x1F;
if(hdr->bitstream_id > 16)
return AC3_PARSE_ERROR_BSID;
if(hdr->bitstream_id <= 10) {
/* Normal AC-3 */
hdr->crc1 = get_bits(&gbc, 16);
hdr->sr_code = get_bits(&gbc, 2);
if(hdr->sr_code == 3)
return AC3_PARSE_ERROR_SAMPLE_RATE;
frame_size_code = get_bits(&gbc, 6);
if(frame_size_code > 37)
return AC3_PARSE_ERROR_FRAME_SIZE;
skip_bits(&gbc, 5); // skip bsid, already got it
skip_bits(&gbc, 3); // skip bitstream mode
hdr->channel_mode = get_bits(&gbc, 3);
if((hdr->channel_mode & 1) && hdr->channel_mode != AC3_CHMODE_MONO) {
skip_bits(&gbc, 2); // skip center mix level
}
if(hdr->channel_mode & 4) {
skip_bits(&gbc, 2); // skip surround mix level
}
if(hdr->channel_mode == AC3_CHMODE_STEREO) {
skip_bits(&gbc, 2); // skip dolby surround mode
}
hdr->lfe_on = get_bits1(&gbc);
hdr->sr_shift = FFMAX(hdr->bitstream_id, 8) - 8;
hdr->sample_rate = ff_ac3_sample_rate_tab[hdr->sr_code] >> hdr->sr_shift;
hdr->bit_rate = (ff_ac3_bitrate_tab[frame_size_code>>1] * 1000) >> hdr->sr_shift;
hdr->channels = ff_ac3_channels_tab[hdr->channel_mode] + hdr->lfe_on;
hdr->frame_size = ff_ac3_frame_size_tab[frame_size_code][hdr->sr_code] * 2;
} else {
int ff_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int buf_size)
{
GetBitContext gb;
int specific_config_bitindex;
init_get_bits(&gb, buf, buf_size*8);
c->object_type = get_object_type(&gb);
c->sample_rate = get_sample_rate(&gb, &c->sampling_index);
c->chan_config = get_bits(&gb, 4);
if (c->chan_config < FF_ARRAY_ELEMS(ff_mpeg4audio_channels))
c->channels = ff_mpeg4audio_channels[c->chan_config];
c->sbr = -1;
if (c->object_type == AOT_SBR) {
c->ext_object_type = c->object_type;
c->sbr = 1;
c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index);
c->object_type = get_object_type(&gb);
if (c->object_type == AOT_ER_BSAC)
c->ext_chan_config = get_bits(&gb, 4);
} else {
c->ext_object_type = AOT_NULL;
c->ext_sample_rate = 0;
}
specific_config_bitindex = get_bits_count(&gb);
if (c->object_type == AOT_ALS) {
skip_bits(&gb, 5);
if (show_bits_long(&gb, 24) != MKBETAG('\0','A','L','S'))
skip_bits_long(&gb, 24);
specific_config_bitindex = get_bits_count(&gb);
if (parse_config_ALS(&gb, c))
return -1;
}
if (c->ext_object_type != AOT_SBR) {
int bits_left = buf_size*8 - get_bits_count(&gb);
for (; bits_left > 15; bits_left--) {
if (show_bits(&gb, 11) == 0x2b7) { // sync extension
get_bits(&gb, 11);
c->ext_object_type = get_object_type(&gb);
if (c->ext_object_type == AOT_SBR && (c->sbr = get_bits1(&gb)) == 1)
c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index);
break;
} else
get_bits1(&gb); // skip 1 bit
}
}
return specific_config_bitindex;
}
/**
* Get context-dependent Golomb code, decode it and update context
*/
static inline int ls_get_code_regular(GetBitContext *gb, JLSState *state, int Q){
int k, ret;
for(k = 0; (state->N[Q] << k) < state->A[Q]; k++);
#ifdef JLS_BROKEN
if(!show_bits_long(gb, 32))return -1;
#endif
ret = get_ur_golomb_jpegls(gb, k, state->limit, state->qbpp);
/* decode mapped error */
if(ret & 1)
ret = -((ret + 1) >> 1);
else
static inline int decode_subframe(FLACContext *s, int channel)
{
int32_t *decoded = s->decoded[channel];
int type, wasted = 0;
int bps = s->bps;
int i, tmp, ret;
if (channel == 0) {
if (s->ch_mode == FLAC_CHMODE_RIGHT_SIDE)
bps++;
} else {
if (s->ch_mode == FLAC_CHMODE_LEFT_SIDE || s->ch_mode == FLAC_CHMODE_MID_SIDE)
bps++;
}
if (get_bits1(&s->gb)) {
av_log(s->avctx, AV_LOG_ERROR, "invalid subframe padding\n");
return AVERROR_INVALIDDATA;
}
type = get_bits(&s->gb, 6);
if (get_bits1(&s->gb)) {
int left = get_bits_left(&s->gb);
wasted = 1;
if ( left < 0 ||
(left < bps && !show_bits_long(&s->gb, left)) ||
!show_bits_long(&s->gb, bps)) {
av_log(s->avctx, AV_LOG_ERROR,
"Invalid number of wasted bits > available bits (%d) - left=%d\n",
bps, left);
return AVERROR_INVALIDDATA;
}
while (!get_bits1(&s->gb))
wasted++;
bps -= wasted;
}
if (bps > 32) {
avpriv_report_missing_feature(s->avctx, "Decorrelated bit depth > 32");
return AVERROR_PATCHWELCOME;
}
//FIXME use av_log2 for types
if (type == 0) {
tmp = get_sbits_long(&s->gb, bps);
for (i = 0; i < s->blocksize; i++)
decoded[i] = tmp;
} else if (type == 1) {
for (i = 0; i < s->blocksize; i++)
decoded[i] = get_sbits_long(&s->gb, bps);
} else if ((type >= 8) && (type <= 12)) {
if ((ret = decode_subframe_fixed(s, decoded, type & ~0x8, bps)) < 0)
return ret;
} else if (type >= 32) {
if ((ret = decode_subframe_lpc(s, decoded, (type & ~0x20)+1, bps)) < 0)
return ret;
} else {
av_log(s->avctx, AV_LOG_ERROR, "invalid coding type\n");
return AVERROR_INVALIDDATA;
}
if (wasted) {
int i;
for (i = 0; i < s->blocksize; i++)
decoded[i] <<= wasted;
}
return 0;
}
int ff_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, int buf_size)
{
GetBitContext gb;
int specific_config_bitindex;
init_get_bits(&gb, buf, buf_size*8);
c->object_type = get_object_type(&gb);
c->sample_rate = get_sample_rate(&gb, &c->sampling_index);
c->chan_config = get_bits(&gb, 4);
if (c->chan_config < FF_ARRAY_ELEMS(ff_mpeg4audio_channels))
c->channels = ff_mpeg4audio_channels[c->chan_config];
c->sbr = -1;
c->ps = -1;
if (c->object_type == AOT_SBR || (c->object_type == AOT_PS &&
// check for W6132 Annex YYYY draft MP3onMP4
!(show_bits(&gb, 3) & 0x03 && !(show_bits(&gb, 9) & 0x3F)))) {
if (c->object_type == AOT_PS)
c->ps = 1;
c->ext_object_type = AOT_SBR;
c->sbr = 1;
c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index);
c->object_type = get_object_type(&gb);
if (c->object_type == AOT_ER_BSAC)
c->ext_chan_config = get_bits(&gb, 4);
} else {
c->ext_object_type = AOT_NULL;
c->ext_sample_rate = 0;
}
specific_config_bitindex = get_bits_count(&gb);
if (c->object_type == AOT_ALS) {
skip_bits(&gb, 5);
if (show_bits_long(&gb, 24) != MKBETAG('\0','A','L','S'))
skip_bits_long(&gb, 24);
specific_config_bitindex = get_bits_count(&gb);
if (parse_config_ALS(&gb, c))
return -1;
}
if (c->ext_object_type != AOT_SBR) {
while (get_bits_left(&gb) > 15) {
if (show_bits(&gb, 11) == 0x2b7) { // sync extension
get_bits(&gb, 11);
c->ext_object_type = get_object_type(&gb);
if (c->ext_object_type == AOT_SBR && (c->sbr = get_bits1(&gb)) == 1)
c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index);
if (get_bits_left(&gb) > 11 && get_bits(&gb, 11) == 0x548)
c->ps = get_bits1(&gb);
break;
} else
get_bits1(&gb); // skip 1 bit
}
}
//PS requires SBR
if (!c->sbr)
c->ps = 0;
//Limit implicit PS to the HE-AACv2 Profile
if ((c->ps == -1 && c->object_type != AOT_AAC_LC) || c->channels & ~0x01)
c->ps = 0;
return specific_config_bitindex;
}
