-#define AAC_HEADER_SIZE 7
-
-int ff_aac_parse_header(GetBitContext *gbc, AACADTSHeaderInfo *hdr)
-{
- int size, rdb, ch, sr;
- int aot, crc_abs;
-
- if(get_bits(gbc, 12) != 0xfff)
- return AAC_AC3_PARSE_ERROR_SYNC;
-
- skip_bits1(gbc); /* id */
- skip_bits(gbc, 2); /* layer */
- crc_abs = get_bits1(gbc); /* protection_absent */
- aot = get_bits(gbc, 2); /* profile_objecttype */
- sr = get_bits(gbc, 4); /* sample_frequency_index */
- if(!ff_mpeg4audio_sample_rates[sr])
- return AAC_AC3_PARSE_ERROR_SAMPLE_RATE;
- skip_bits1(gbc); /* private_bit */
- ch = get_bits(gbc, 3); /* channel_configuration */
-
- if(!ff_mpeg4audio_channels[ch])
- return AAC_AC3_PARSE_ERROR_CHANNEL_CFG;
-
- skip_bits1(gbc); /* original/copy */
- skip_bits1(gbc); /* home */
-
- /* adts_variable_header */
- skip_bits1(gbc); /* copyright_identification_bit */
- skip_bits1(gbc); /* copyright_identification_start */
- size = get_bits(gbc, 13); /* aac_frame_length */
- if(size < AAC_HEADER_SIZE)
- return AAC_AC3_PARSE_ERROR_FRAME_SIZE;
-
- skip_bits(gbc, 11); /* adts_buffer_fullness */
- rdb = get_bits(gbc, 2); /* number_of_raw_data_blocks_in_frame */
-
- hdr->object_type = aot + 1;
- hdr->chan_config = ch;
- hdr->crc_absent = crc_abs;
- hdr->num_aac_frames = rdb + 1;
- hdr->sampling_index = sr;
- hdr->sample_rate = ff_mpeg4audio_sample_rates[sr];
- hdr->samples = (rdb + 1) * 1024;
- hdr->bit_rate = size * 8 * hdr->sample_rate / hdr->samples;
-
- return size;
-}
-