diff options
Diffstat (limited to 'libavcodec/mpeg4audio.c')
| -rw-r--r-- | libavcodec/mpeg4audio.c | 76 |
1 files changed, 42 insertions, 34 deletions
diff --git a/libavcodec/mpeg4audio.c b/libavcodec/mpeg4audio.c index 5f85b64..b6bb323 100644 --- a/libavcodec/mpeg4audio.c +++ b/libavcodec/mpeg4audio.c @@ -83,70 +83,62 @@ static inline int get_sample_rate(GetBitContext *gb, int *index) avpriv_mpeg4audio_sample_rates[*index]; } -int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, - int bit_size, int sync_extension) +int ff_mpeg4audio_get_config_gb(MPEG4AudioConfig *c, GetBitContext *gb, + int sync_extension) { - GetBitContext gb; int specific_config_bitindex, ret; - - if (bit_size <= 0) - return AVERROR_INVALIDDATA; - - ret = init_get_bits(&gb, buf, bit_size); - if (ret < 0) - return ret; - - c->object_type = get_object_type(&gb); - c->sample_rate = get_sample_rate(&gb, &c->sampling_index); - c->chan_config = get_bits(&gb, 4); + int start_bit_index = get_bits_count(gb); + 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)))) { + !(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); + 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); + 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); + 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); + 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); + specific_config_bitindex = get_bits_count(gb); - ret = parse_config_ALS(&gb, c); + ret = parse_config_ALS(gb, c); if (ret < 0) return ret; } if (c->ext_object_type != AOT_SBR && sync_extension) { - 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); + 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 (c->ext_sample_rate == c->sample_rate) c->sbr = -1; } - if (get_bits_left(&gb) > 11 && get_bits(&gb, 11) == 0x548) - c->ps = get_bits1(&gb); + if (get_bits_left(gb) > 11 && get_bits(gb, 11) == 0x548) + c->ps = get_bits1(gb); break; } else - get_bits1(&gb); // skip 1 bit + get_bits1(gb); // skip 1 bit } } @@ -157,7 +149,23 @@ int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, if ((c->ps == -1 && c->object_type != AOT_AAC_LC) || c->channels & ~0x01) c->ps = 0; - return specific_config_bitindex; + return specific_config_bitindex - start_bit_index; +} + +int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf, + int bit_size, int sync_extension) +{ + GetBitContext gb; + int ret; + + if (bit_size <= 0) + return AVERROR_INVALIDDATA; + + ret = init_get_bits(&gb, buf, bit_size); + if (ret < 0) + return ret; + + return ff_mpeg4audio_get_config_gb(c, &gb, sync_extension); } static av_always_inline unsigned int copy_bits(PutBitContext *pb, |
