| /* |
| * MPEG-2/4 AAC ADTS to MPEG-4 Audio Specific Configuration bitstream filter |
| * Copyright (c) 2009 Alex Converse <alex.converse@gmail.com> |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include "adts_header.h" |
| #include "adts_parser.h" |
| #include "bsf.h" |
| #include "bsf_internal.h" |
| #include "put_bits.h" |
| #include "get_bits.h" |
| #include "mpeg4audio.h" |
| #include "internal.h" |
| |
| typedef struct AACBSFContext { |
| int first_frame_done; |
| } AACBSFContext; |
| |
| /** |
| * This filter creates an MPEG-4 AudioSpecificConfig from an MPEG-2/4 |
| * ADTS header and removes the ADTS header. |
| */ |
| static int aac_adtstoasc_filter(AVBSFContext *bsfc, AVPacket *pkt) |
| { |
| AACBSFContext *ctx = bsfc->priv_data; |
| |
| GetBitContext gb; |
| PutBitContext pb; |
| AACADTSHeaderInfo hdr; |
| int ret; |
| |
| ret = ff_bsf_get_packet_ref(bsfc, pkt); |
| if (ret < 0) |
| return ret; |
| |
| if (bsfc->par_in->extradata && pkt->size >= 2 && (AV_RB16(pkt->data) >> 4) != 0xfff) |
| return 0; |
| |
| if (pkt->size < AV_AAC_ADTS_HEADER_SIZE) |
| goto packet_too_small; |
| |
| init_get_bits(&gb, pkt->data, AV_AAC_ADTS_HEADER_SIZE * 8); |
| |
| if (ff_adts_header_parse(&gb, &hdr) < 0) { |
| av_log(bsfc, AV_LOG_ERROR, "Error parsing ADTS frame header!\n"); |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| |
| if (!hdr.crc_absent && hdr.num_aac_frames > 1) { |
| avpriv_report_missing_feature(bsfc, |
| "Multiple RDBs per frame with CRC"); |
| ret = AVERROR_PATCHWELCOME; |
| goto fail; |
| } |
| |
| pkt->size -= AV_AAC_ADTS_HEADER_SIZE + 2 * !hdr.crc_absent; |
| if (pkt->size <= 0) |
| goto packet_too_small; |
| pkt->data += AV_AAC_ADTS_HEADER_SIZE + 2 * !hdr.crc_absent; |
| |
| if (!ctx->first_frame_done) { |
| int pce_size = 0; |
| uint8_t pce_data[MAX_PCE_SIZE]; |
| uint8_t *extradata; |
| |
| if (!hdr.chan_config) { |
| init_get_bits(&gb, pkt->data, pkt->size * 8); |
| if (get_bits(&gb, 3) != 5) { |
| avpriv_report_missing_feature(bsfc, |
| "PCE-based channel configuration " |
| "without PCE as first syntax " |
| "element"); |
| ret = AVERROR_PATCHWELCOME; |
| goto fail; |
| } |
| init_put_bits(&pb, pce_data, MAX_PCE_SIZE); |
| pce_size = ff_copy_pce_data(&pb, &gb) / 8; |
| flush_put_bits(&pb); |
| pkt->size -= get_bits_count(&gb)/8; |
| pkt->data += get_bits_count(&gb)/8; |
| } |
| |
| extradata = av_packet_new_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA, |
| 2 + pce_size); |
| if (!extradata) { |
| ret = AVERROR(ENOMEM); |
| goto fail; |
| } |
| |
| init_put_bits(&pb, extradata, 2 + pce_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(extradata + 2, pce_data, pce_size); |
| } |
| |
| ctx->first_frame_done = 1; |
| } |
| |
| return 0; |
| |
| packet_too_small: |
| av_log(bsfc, AV_LOG_ERROR, "Input packet too small\n"); |
| ret = AVERROR_INVALIDDATA; |
| fail: |
| av_packet_unref(pkt); |
| return ret; |
| } |
| |
| static int aac_adtstoasc_init(AVBSFContext *ctx) |
| { |
| /* Validate the extradata if the stream is already MPEG-4 AudioSpecificConfig */ |
| if (ctx->par_in->extradata) { |
| MPEG4AudioConfig mp4ac; |
| int ret = avpriv_mpeg4audio_get_config2(&mp4ac, ctx->par_in->extradata, |
| ctx->par_in->extradata_size, 1, ctx); |
| if (ret < 0) { |
| av_log(ctx, AV_LOG_ERROR, "Error parsing AudioSpecificConfig extradata!\n"); |
| return ret; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static const enum AVCodecID codec_ids[] = { |
| AV_CODEC_ID_AAC, AV_CODEC_ID_NONE, |
| }; |
| |
| const AVBitStreamFilter ff_aac_adtstoasc_bsf = { |
| .name = "aac_adtstoasc", |
| .priv_data_size = sizeof(AACBSFContext), |
| .init = aac_adtstoasc_init, |
| .filter = aac_adtstoasc_filter, |
| .codec_ids = codec_ids, |
| }; |