2 * codec2 muxer and demuxers
3 * Copyright (c) 2017 Tomas Härdin
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libavcodec/codec2utils.h"
24 #include "libavutil/intreadwrite.h"
25 #include "avio_internal.h"
32 #define AVPRIV_CODEC2_HEADER_SIZE 7
33 #define AVPRIV_CODEC2_MAGIC 0xC0DEC2
35 //the lowest version we should ever run across is 0.8
36 //we may run across later versions as the format evolves
37 #define EXPECTED_CODEC2_MAJOR_VERSION 0
38 #define EXPECTED_CODEC2_MINOR_VERSION 8
43 int frames_per_packet;
46 static int codec2_probe(const AVProbeData *p)
48 //must start wih C0 DE C2
49 if (AV_RB24(p->buf) != AVPRIV_CODEC2_MAGIC) {
53 //no .c2 files prior to 0.8
54 //be strict about major version while we're at it
55 if (p->buf[3] != EXPECTED_CODEC2_MAJOR_VERSION ||
56 p->buf[4] < EXPECTED_CODEC2_MINOR_VERSION) {
60 //32 bits of identification -> low score
61 return AVPROBE_SCORE_EXTENSION + 1;
64 static int codec2_read_header_common(AVFormatContext *s, AVStream *st)
66 int mode = avpriv_codec2_mode_from_extradata(st->codecpar->extradata);
68 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
69 st->codecpar->codec_id = AV_CODEC_ID_CODEC2;
70 st->codecpar->sample_rate = 8000;
71 st->codecpar->channels = 1;
72 st->codecpar->format = AV_SAMPLE_FMT_S16;
73 st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
74 st->codecpar->bit_rate = avpriv_codec2_mode_bit_rate(s, mode);
75 st->codecpar->frame_size = avpriv_codec2_mode_frame_size(s, mode);
76 st->codecpar->block_align = avpriv_codec2_mode_block_align(s, mode);
78 if (st->codecpar->bit_rate <= 0 ||
79 st->codecpar->frame_size <= 0 ||
80 st->codecpar->block_align <= 0) {
81 return AVERROR_INVALIDDATA;
84 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
89 static int codec2_read_header(AVFormatContext *s)
91 AVStream *st = avformat_new_stream(s, NULL);
95 return AVERROR(ENOMEM);
98 if (avio_rb24(s->pb) != AVPRIV_CODEC2_MAGIC) {
99 av_log(s, AV_LOG_ERROR, "not a .c2 file\n");
100 return AVERROR_INVALIDDATA;
103 ret = ff_alloc_extradata(st->codecpar, AVPRIV_CODEC2_EXTRADATA_SIZE);
108 ret = ffio_read_size(s->pb, st->codecpar->extradata, AVPRIV_CODEC2_EXTRADATA_SIZE);
113 version = avpriv_codec2_version_from_extradata(st->codecpar->extradata);
114 if ((version >> 8) != EXPECTED_CODEC2_MAJOR_VERSION) {
115 avpriv_report_missing_feature(s, "Major version %i", version >> 8);
116 return AVERROR_PATCHWELCOME;
119 s->internal->data_offset = AVPRIV_CODEC2_HEADER_SIZE;
121 return codec2_read_header_common(s, st);
124 static int codec2_read_packet(AVFormatContext *s, AVPacket *pkt)
126 Codec2Context *c2 = s->priv_data;
127 AVStream *st = s->streams[0];
128 int ret, size, n, block_align, frame_size;
130 block_align = st->codecpar->block_align;
131 frame_size = st->codecpar->frame_size;
133 if (block_align <= 0 || frame_size <= 0 || c2->frames_per_packet <= 0) {
134 return AVERROR(EINVAL);
137 //try to read desired number of frames, compute n from to actual number of bytes read
138 size = c2->frames_per_packet * block_align;
139 ret = av_get_packet(s->pb, pkt, size);
144 //only set duration - compute_pkt_fields() and ff_pcm_read_seek() takes care of everything else
145 //tested by spamming the seek functionality in ffplay
146 n = ret / block_align;
147 pkt->duration = n * frame_size;
152 static int codec2_write_header(AVFormatContext *s)
156 if (s->nb_streams != 1 || s->streams[0]->codecpar->codec_id != AV_CODEC_ID_CODEC2) {
157 av_log(s, AV_LOG_ERROR, ".c2 files must have exactly one codec2 stream\n");
158 return AVERROR(EINVAL);
163 if (st->codecpar->extradata_size != AVPRIV_CODEC2_EXTRADATA_SIZE) {
164 av_log(s, AV_LOG_ERROR, ".c2 files require exactly %i bytes of extradata (got %i)\n",
165 AVPRIV_CODEC2_EXTRADATA_SIZE, st->codecpar->extradata_size);
166 return AVERROR(EINVAL);
169 avio_wb24(s->pb, AVPRIV_CODEC2_MAGIC);
170 avio_write(s->pb, st->codecpar->extradata, AVPRIV_CODEC2_EXTRADATA_SIZE);
175 static int codec2raw_read_header(AVFormatContext *s)
177 Codec2Context *c2 = s->priv_data;
182 //FIXME: using a default value of -1 for mandatory options is an incredibly ugly hack
183 av_log(s, AV_LOG_ERROR, "-mode must be set in order to make sense of raw codec2 files\n");
184 return AVERROR(EINVAL);
187 st = avformat_new_stream(s, NULL);
189 return AVERROR(ENOMEM);
192 ret = ff_alloc_extradata(st->codecpar, AVPRIV_CODEC2_EXTRADATA_SIZE);
197 s->internal->data_offset = 0;
198 avpriv_codec2_make_extradata(st->codecpar->extradata, c2->mode);
200 return codec2_read_header_common(s, st);
203 //transcoding report2074.c2 to wav went from 7.391s to 5.322s with -frames_per_packet 1000 compared to default, same sha1sum
204 #define FRAMES_PER_PACKET \
205 { "frames_per_packet", "Number of frames to read at a time. Higher = faster decoding, lower granularity", \
206 offsetof(Codec2Context, frames_per_packet), AV_OPT_TYPE_INT, {.i64 = 1}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM}
208 static const AVOption codec2_options[] = {
213 static const AVOption codec2raw_options[] = {
214 AVPRIV_CODEC2_AVOPTIONS("codec2 mode [mandatory]", Codec2Context, -1, -1, AV_OPT_FLAG_DECODING_PARAM),
219 static const AVClass codec2_mux_class = {
220 .class_name = "codec2 muxer",
221 .item_name = av_default_item_name,
222 .version = LIBAVUTIL_VERSION_INT,
223 .category = AV_CLASS_CATEGORY_DEMUXER,
226 static const AVClass codec2_demux_class = {
227 .class_name = "codec2 demuxer",
228 .item_name = av_default_item_name,
229 .option = codec2_options,
230 .version = LIBAVUTIL_VERSION_INT,
231 .category = AV_CLASS_CATEGORY_DEMUXER,
234 static const AVClass codec2raw_demux_class = {
235 .class_name = "codec2raw demuxer",
236 .item_name = av_default_item_name,
237 .option = codec2raw_options,
238 .version = LIBAVUTIL_VERSION_INT,
239 .category = AV_CLASS_CATEGORY_DEMUXER,
242 #if CONFIG_CODEC2_DEMUXER
243 AVInputFormat ff_codec2_demuxer = {
245 .long_name = NULL_IF_CONFIG_SMALL("codec2 .c2 demuxer"),
246 .priv_data_size = sizeof(Codec2Context),
248 .read_probe = codec2_probe,
249 .read_header = codec2_read_header,
250 .read_packet = codec2_read_packet,
251 .read_seek = ff_pcm_read_seek,
252 .flags = AVFMT_GENERIC_INDEX,
253 .raw_codec_id = AV_CODEC_ID_CODEC2,
254 .priv_class = &codec2_demux_class,
258 #if CONFIG_CODEC2_MUXER
259 AVOutputFormat ff_codec2_muxer = {
261 .long_name = NULL_IF_CONFIG_SMALL("codec2 .c2 muxer"),
262 .priv_data_size = sizeof(Codec2Context),
264 .audio_codec = AV_CODEC_ID_CODEC2,
265 .video_codec = AV_CODEC_ID_NONE,
266 .write_header = codec2_write_header,
267 .write_packet = ff_raw_write_packet,
268 .flags = AVFMT_NOTIMESTAMPS,
269 .priv_class = &codec2_mux_class,
273 #if CONFIG_CODEC2RAW_DEMUXER
274 AVInputFormat ff_codec2raw_demuxer = {
276 .long_name = NULL_IF_CONFIG_SMALL("raw codec2 demuxer"),
277 .priv_data_size = sizeof(Codec2Context),
278 .read_header = codec2raw_read_header,
279 .read_packet = codec2_read_packet,
280 .read_seek = ff_pcm_read_seek,
281 .flags = AVFMT_GENERIC_INDEX,
282 .raw_codec_id = AV_CODEC_ID_CODEC2,
283 .priv_class = &codec2raw_demux_class,