static int aac_adtstoasc_filter(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args, uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size, int keyframe) { GetBitContext gb; PutBitContext pb; AACADTSHeaderInfo hdr; AACBSFContext *ctx = bsfc->priv_data; init_get_bits(&gb, buf, AAC_ADTS_HEADER_SIZE*8); *poutbuf = (uint8_t*) buf; *poutbuf_size = buf_size; if (avctx->extradata) if (show_bits(&gb, 12) != 0xfff) return 0; if (avpriv_aac_parse_header(&gb, &hdr) < 0) { av_log(avctx, AV_LOG_ERROR, "Error parsing ADTS frame header!\n"); return -1; } if (!hdr.crc_absent && hdr.num_aac_frames > 1) { avpriv_report_missing_feature(avctx, "Multiple RDBs per frame with CRC"); return AVERROR_PATCHWELCOME; } buf += AAC_ADTS_HEADER_SIZE + 2*!hdr.crc_absent; buf_size -= AAC_ADTS_HEADER_SIZE + 2*!hdr.crc_absent; if (!ctx->first_frame_done) { int pce_size = 0; uint8_t pce_data[MAX_PCE_SIZE]; if (!hdr.chan_config) { init_get_bits(&gb, buf, buf_size * 8); if (get_bits(&gb, 3) != 5) { avpriv_report_missing_feature(avctx, "PCE-based channel configuration " "without PCE as first syntax " "element"); return AVERROR_PATCHWELCOME; } init_put_bits(&pb, pce_data, MAX_PCE_SIZE); pce_size = avpriv_copy_pce_data(&pb, &gb)/8; flush_put_bits(&pb); buf_size -= get_bits_count(&gb)/8; buf += get_bits_count(&gb)/8; } avctx->extradata_size = 2 + pce_size; avctx->extradata = av_mallocz(avctx->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE); init_put_bits(&pb, avctx->extradata, avctx->extradata_size); put_bits(&pb, 5, hdr.object_type); put_bits(&pb, 4, hdr.sampling_index); put_bits(&pb, 4, hdr.chan_config); put_bits(&pb, 1, 0); //frame length - 1024 samples put_bits(&pb, 1, 0); //does not depend on core coder put_bits(&pb, 1, 0); //is not extension flush_put_bits(&pb); if (pce_size) { memcpy(avctx->extradata + 2, pce_data, pce_size); } ctx->first_frame_done = 1; } *poutbuf = (uint8_t*) buf; *poutbuf_size = buf_size; return 0; }