A file format is described in Bluetooth SIG LC3 and ETSI TS 103 634, for test purpose. This is the format implemented here.
Signed-off-by: Antoine Soulier <asoul...@google.com> --- Changelog | 1 + doc/muxers.texi | 6 ++ libavformat/Makefile | 2 + libavformat/allformats.c | 2 + libavformat/lc3dec.c | 135 +++++++++++++++++++++++++++++++++++++++ libavformat/lc3enc.c | 100 +++++++++++++++++++++++++++++ 6 files changed, 246 insertions(+) create mode 100644 libavformat/lc3dec.c create mode 100644 libavformat/lc3enc.c diff --git a/Changelog b/Changelog index 83a4cf7888..08c200a41d 100644 --- a/Changelog +++ b/Changelog @@ -2,6 +2,7 @@ Entries are sorted chronologically from oldest to youngest within each release, releases are sorted from youngest to oldest. version <next>: +- LC3/LC3plus demuxer and muxer - LC3/LC3plus decoding/encoding using external library liblc3 diff --git a/doc/muxers.texi b/doc/muxers.texi index a10a8e216f..9687746c30 100644 --- a/doc/muxers.texi +++ b/doc/muxers.texi @@ -2612,6 +2612,12 @@ WebDAV server every second: ffmpeg -f x11grab -framerate 1 -i :0.0 -q:v 6 -update 1 -protocol_opts method=PUT http://example.com/desktop.jpg @end example +@section lc3 +Bluetooth SIG Low Complexity Communication Codec audio (LC3), or +ETSI TS 103 634 Low Complexity Communication Codec plus (LC3plus). + +This muxer accepts a single @code{lc3} audio stream. + @section matroska Matroska container muxer. diff --git a/libavformat/Makefile b/libavformat/Makefile index 44aa485029..4961c42852 100644 --- a/libavformat/Makefile +++ b/libavformat/Makefile @@ -332,6 +332,8 @@ OBJS-$(CONFIG_KVAG_DEMUXER) += kvag.o OBJS-$(CONFIG_KVAG_MUXER) += kvag.o rawenc.o OBJS-$(CONFIG_LAF_DEMUXER) += lafdec.o OBJS-$(CONFIG_LATM_MUXER) += latmenc.o rawenc.o +OBJS-$(CONFIG_LC3_DEMUXER) += lc3dec.o +OBJS-$(CONFIG_LC3_MUXER) += lc3enc.o OBJS-$(CONFIG_LMLM4_DEMUXER) += lmlm4.o OBJS-$(CONFIG_LOAS_DEMUXER) += loasdec.o rawdec.o OBJS-$(CONFIG_LUODAT_DEMUXER) += luodatdec.o diff --git a/libavformat/allformats.c b/libavformat/allformats.c index 9df42bb87a..0b36a7c3eb 100644 --- a/libavformat/allformats.c +++ b/libavformat/allformats.c @@ -252,6 +252,8 @@ extern const FFInputFormat ff_kvag_demuxer; extern const FFOutputFormat ff_kvag_muxer; extern const FFInputFormat ff_laf_demuxer; extern const FFOutputFormat ff_latm_muxer; +extern const FFInputFormat ff_lc3_demuxer; +extern const FFOutputFormat ff_lc3_muxer; extern const FFInputFormat ff_lmlm4_demuxer; extern const FFInputFormat ff_loas_demuxer; extern const FFInputFormat ff_luodat_demuxer; diff --git a/libavformat/lc3dec.c b/libavformat/lc3dec.c new file mode 100644 index 0000000000..c377df4c63 --- /dev/null +++ b/libavformat/lc3dec.c @@ -0,0 +1,135 @@ +/* + * LC3 demuxer + * Copyright (C) 2024 Antoine Soulier <asoul...@google.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 + */ + +/** + * @file + * Based on the file format specified by : + * + * - Bluetooth SIG - Low Complexity Communication Codec Test Suite + * https://www.bluetooth.org/docman/handlers/downloaddoc.ashx?doc_id=502301 + * 3.2.8.2 Reference LC3 Codec Bitstream Format + * + * - ETSI TI 103 634 V1.4.1 - Low Complexity Communication Codec plus + * https://www.etsi.org/deliver/etsi_ts/103600_103699/103634/01.04.01_60/ts_103634v010401p.pdf + * LC3plus conformance script package + */ + +#include "libavcodec/packet.h" +#include "libavutil/intreadwrite.h" + +#include "avformat.h" +#include "avio.h" +#include "demux.h" +#include "internal.h" + +typedef struct LC3DemuxContext { + int frame_samples; + int64_t position; + int64_t length; +} LC3DemuxContext; + +static int lc3_read_header(AVFormatContext *s) +{ + LC3DemuxContext *lc3 = s->priv_data; + AVStream *st = NULL; + uint16_t tag, hdr_size; + uint16_t frame_10us; + uint32_t length; + int ep_mode, hr_mode; + int srate_hz, channels, bit_rate; + int num_extra_params, ret; + + tag = avio_rb16(s->pb); + hdr_size = avio_rl16(s->pb); + + if (tag != 0x1ccc || hdr_size < 9 * sizeof(uint16_t)) + return AVERROR_INVALIDDATA; + + num_extra_params = hdr_size / sizeof(uint16_t) - 9; + + srate_hz = avio_rl16(s->pb) * 100; + bit_rate = avio_rl16(s->pb) * 100; + channels = avio_rl16(s->pb); + frame_10us = avio_rl16(s->pb); + ep_mode = avio_rl16(s->pb) != 0; + length = avio_rl32(s->pb); + hr_mode = num_extra_params >= 1 && avio_rl16(s->pb); + + st = avformat_new_stream(s, NULL); + if (!st) + return AVERROR(ENOMEM); + + avpriv_set_pts_info(st, 64, 1, srate_hz); + st->duration = length; + + st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; + st->codecpar->codec_id = AV_CODEC_ID_LC3; + st->codecpar->sample_rate = srate_hz; + st->codecpar->bit_rate = bit_rate; + st->codecpar->ch_layout.nb_channels = channels; + + if ((ret = ff_alloc_extradata(st->codecpar, 6)) < 0) { + av_log(s, AV_LOG_ERROR, "Could not allocate extradata.\n"); + return ret; + } + + AV_WL16(st->codecpar->extradata + 0, frame_10us); + AV_WL16(st->codecpar->extradata + 2, ep_mode); + AV_WL16(st->codecpar->extradata + 4, hr_mode); + + lc3->frame_samples = av_rescale(frame_10us, srate_hz, 100*1000); + + lc3->position = 0; + lc3->length = st->duration + + av_rescale(frame_10us == 750 ? 400 : 250, srate_hz, 100*1000); + + return 0; +} + +static int lc3_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + LC3DemuxContext *lc3 = s->priv_data; + AVIOContext *pb = s->pb; + int ret; + + ret = av_get_packet(s->pb, pkt, avio_rl16(pb)); + if (ret < 0) + return ret; + + pkt->duration = lc3->frame_samples; + lc3->position += lc3->frame_samples; + if (lc3->position > lc3->length) { + pkt->duration -= lc3->position - lc3->length; + lc3->position = lc3->length; + } + + return 0; +} + +const FFInputFormat ff_lc3_demuxer = { + .p.name = "lc3", + .p.long_name = NULL_IF_CONFIG_SMALL("LC3 (Low Complexity Communication Codec)"), + .p.extensions = "lc3", + .p.flags = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH | AVFMT_NO_BYTE_SEEK | AVFMT_NOTIMESTAMPS, + .priv_data_size = sizeof(LC3DemuxContext), + .read_header = lc3_read_header, + .read_packet = lc3_read_packet, +}; diff --git a/libavformat/lc3enc.c b/libavformat/lc3enc.c new file mode 100644 index 0000000000..e768212f63 --- /dev/null +++ b/libavformat/lc3enc.c @@ -0,0 +1,100 @@ +/* + * LC3 muxer + * Copyright (C) 2024 Antoine Soulier <asoul...@google.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 + */ + +/** + * @file + * Based on the file format specified by : + * + * - Bluetooth SIG - Low Complexity Communication Codec Test Suite + * https://www.bluetooth.org/docman/handlers/downloaddoc.ashx?doc_id=502301 + * 3.2.8.2 Reference LC3 Codec Bitstream Format + * + * - ETSI TI 103 634 V1.4.1 - Low Complexity Communication Codec plus + * https://www.etsi.org/deliver/etsi_ts/103600_103699/103634/01.04.01_60/ts_103634v010401p.pdf + * LC3plus conformance script package + */ + +#include "libavutil/intreadwrite.h" + +#include "avformat.h" +#include "avio.h" +#include "mux.h" +#include "internal.h" + +static av_cold int lc3_init(AVFormatContext *s) +{ + if (s->nb_streams != 1) { + av_log(s, AV_LOG_ERROR, "This muxer only supports a single stream.\n"); + return AVERROR(EINVAL); + } + + return 0; +} + +static int lc3_write_header(AVFormatContext *s) +{ + AVStream *st = s->streams[0]; + int channels = st->codecpar->ch_layout.nb_channels; + int srate_hz = st->codecpar->sample_rate; + int bit_rate = st->codecpar->bit_rate; + int frame_us, ep_mode, hr_mode; + uint32_t nb_samples = av_rescale_q( + st->duration, st->time_base, (AVRational){ 1, srate_hz }); + + if (st->codecpar->extradata_size < 6) + return AVERROR_INVALIDDATA; + + frame_us = AV_RL16(st->codecpar->extradata + 0) * 10; + ep_mode = AV_RL16(st->codecpar->extradata + 2) != 0; + hr_mode = AV_RL16(st->codecpar->extradata + 4) != 0; + + avio_wb16(s->pb, 0x1ccc); + avio_wl16(s->pb, (9 + hr_mode) * sizeof(uint16_t)); + avio_wl16(s->pb, srate_hz / 100); + avio_wl16(s->pb, bit_rate / 100); + avio_wl16(s->pb, channels); + avio_wl16(s->pb, frame_us / 10); + avio_wl16(s->pb, ep_mode); + avio_wl32(s->pb, nb_samples); + if (hr_mode) + avio_wl16(s->pb, hr_mode); + + return 0; +} + +static int lc3_write_packet(AVFormatContext *s, AVPacket *pkt) +{ + avio_wl16(s->pb, pkt->size); + avio_write(s->pb, pkt->data, pkt->size); + return 0; +} + +const FFOutputFormat ff_lc3_muxer = { + .p.name = "lc3", + .p.long_name = NULL_IF_CONFIG_SMALL("LC3 (Low Complexity Communication Codec)"), + .p.extensions = "lc3", + .p.audio_codec = AV_CODEC_ID_LC3, + .p.video_codec = AV_CODEC_ID_NONE, + .p.flags = AVFMT_NOTIMESTAMPS, + .init = lc3_init, + .write_header = lc3_write_header, + .write_packet = lc3_write_packet, +}; -- 2.44.0.478.gd926399ef9-goog _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
