FFmpeg
codec2.c
Go to the documentation of this file.
1 /*
2  * codec2 muxer and demuxers
3  * Copyright (c) 2017 Tomas Härdin
4  *
5  * This file is part of FFmpeg.
6  *
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.
11  *
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.
16  *
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
20  */
21 
22 #include <memory.h>
23 #include "libavcodec/codec2utils.h"
25 #include "libavutil/intreadwrite.h"
26 #include "libavutil/opt.h"
27 #include "avio_internal.h"
28 #include "avformat.h"
29 #include "internal.h"
30 #include "rawenc.h"
31 #include "pcm.h"
32 
33 #define CODEC2_HEADER_SIZE 7
34 #define CODEC2_MAGIC 0xC0DEC2
35 
36 //the lowest version we should ever run across is 0.8
37 //we may run across later versions as the format evolves
38 #define EXPECTED_CODEC2_MAJOR_VERSION 0
39 #define EXPECTED_CODEC2_MINOR_VERSION 8
40 
41 typedef struct {
42  const AVClass *class;
43  int mode;
46 
47 static int codec2_probe(const AVProbeData *p)
48 {
49  //must start wih C0 DE C2
50  if (AV_RB24(p->buf) != CODEC2_MAGIC) {
51  return 0;
52  }
53 
54  //no .c2 files prior to 0.8
55  //be strict about major version while we're at it
56  if (p->buf[3] != EXPECTED_CODEC2_MAJOR_VERSION ||
58  return 0;
59  }
60 
61  //32 bits of identification -> low score
62  return AVPROBE_SCORE_EXTENSION + 1;
63 }
64 
65 //Mimics codec2_samples_per_frame()
67 {
68  int frame_size_table[CODEC2_MODE_MAX+1] = {
69  160, // 3200
70  160, // 2400
71  320, // 1600
72  320, // 1400
73  320, // 1300
74  320, // 1200
75  320, // 700
76  320, // 700B
77  320, // 700C
78  };
79 
81  av_log(s, AV_LOG_ERROR, "unknown codec2 mode %i, can't find frame_size\n", mode);
82  return 0;
83  } else {
84  return frame_size_table[mode];
85  }
86 }
87 
88 //Mimics (codec2_bits_per_frame()+7)/8
90 {
91  int block_align_table[CODEC2_MODE_MAX+1] = {
92  8, // 3200
93  6, // 2400
94  8, // 1600
95  7, // 1400
96  7, // 1300
97  6, // 1200
98  4, // 700
99  4, // 700B
100  4, // 700C
101  };
102 
104  av_log(s, AV_LOG_ERROR, "unknown codec2 mode %i, can't find block_align\n", mode);
105  return 0;
106  } else {
107  return block_align_table[mode];
108  }
109 }
110 
111 //Computes bitrate from mode, with frames rounded up to the nearest octet.
112 //So 700 bit/s (28 bits/frame) becomes 800 bits/s (32 bits/frame).
114 {
116  int block_align = codec2_mode_block_align(s, mode);
117 
118  if (frame_size <= 0 || block_align <= 0) {
119  return 0;
120  }
121 
122  return 8 * 8000 * block_align / frame_size;
123 }
124 
126 {
128 
131  st->codecpar->sample_rate = 8000;
132  st->codecpar->channels = 1;
138 
139  if (st->codecpar->bit_rate <= 0 ||
140  st->codecpar->frame_size <= 0 ||
141  st->codecpar->block_align <= 0) {
142  return AVERROR_INVALIDDATA;
143  }
144 
145  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
146 
147  return 0;
148 }
149 
151 {
153  int ret, version;
154 
155  if (!st) {
156  return AVERROR(ENOMEM);
157  }
158 
159  if (avio_rb24(s->pb) != CODEC2_MAGIC) {
160  av_log(s, AV_LOG_ERROR, "not a .c2 file\n");
161  return AVERROR_INVALIDDATA;
162  }
163 
165  if (ret) {
166  return ret;
167  }
168 
170  if (ret < 0) {
171  return ret;
172  }
173 
175  if ((version >> 8) != EXPECTED_CODEC2_MAJOR_VERSION) {
176  avpriv_report_missing_feature(s, "Major version %i", version >> 8);
177  return AVERROR_PATCHWELCOME;
178  }
179 
181 
182  return codec2_read_header_common(s, st);
183 }
184 
186 {
187  Codec2Context *c2 = s->priv_data;
188  AVStream *st = s->streams[0];
189  int ret, size, n, block_align, frame_size;
190 
191  block_align = st->codecpar->block_align;
193 
194  if (block_align <= 0 || frame_size <= 0 || c2->frames_per_packet <= 0) {
195  return AVERROR(EINVAL);
196  }
197 
198  //try to read desired number of frames, compute n from to actual number of bytes read
199  size = c2->frames_per_packet * block_align;
200  ret = av_get_packet(s->pb, pkt, size);
201  if (ret < 0) {
202  return ret;
203  }
204 
205  //only set duration - compute_pkt_fields() and ff_pcm_read_seek() takes care of everything else
206  //tested by spamming the seek functionality in ffplay
207  n = ret / block_align;
208  pkt->duration = n * frame_size;
209 
210  return ret;
211 }
212 
214 {
215  AVStream *st;
216 
217  if (s->nb_streams != 1 || s->streams[0]->codecpar->codec_id != AV_CODEC_ID_CODEC2) {
218  av_log(s, AV_LOG_ERROR, ".c2 files must have exactly one codec2 stream\n");
219  return AVERROR(EINVAL);
220  }
221 
222  st = s->streams[0];
223 
225  av_log(s, AV_LOG_ERROR, ".c2 files require exactly %i bytes of extradata (got %i)\n",
227  return AVERROR(EINVAL);
228  }
229 
230  avio_wb24(s->pb, CODEC2_MAGIC);
232 
233  return 0;
234 }
235 
237 {
238  Codec2Context *c2 = s->priv_data;
239  AVStream *st;
240  int ret;
241 
242  if (c2->mode < 0) {
243  //FIXME: using a default value of -1 for mandatory options is an incredibly ugly hack
244  av_log(s, AV_LOG_ERROR, "-mode must be set in order to make sense of raw codec2 files\n");
245  return AVERROR(EINVAL);
246  }
247 
248  st = avformat_new_stream(s, NULL);
249  if (!st) {
250  return AVERROR(ENOMEM);
251  }
252 
254  if (ret) {
255  return ret;
256  }
257 
259 
260  return codec2_read_header_common(s, st);
261 }
262 
263 //transcoding report2074.c2 to wav went from 7.391s to 5.322s with -frames_per_packet 1000 compared to default, same sha1sum
264 #define FRAMES_PER_PACKET \
265  { "frames_per_packet", "Number of frames to read at a time. Higher = faster decoding, lower granularity", \
266  offsetof(Codec2Context, frames_per_packet), AV_OPT_TYPE_INT, {.i64 = 1}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM}
267 
268 static const AVOption codec2_options[] = {
270  { NULL },
271 };
272 
273 static const AVOption codec2raw_options[] = {
274  CODEC2_AVOPTIONS("codec2 mode [mandatory]", Codec2Context, -1, -1, AV_OPT_FLAG_DECODING_PARAM),
276  { NULL },
277 };
278 
279 static const AVClass codec2_demux_class = {
280  .class_name = "codec2 demuxer",
281  .item_name = av_default_item_name,
282  .option = codec2_options,
283  .version = LIBAVUTIL_VERSION_INT,
284  .category = AV_CLASS_CATEGORY_DEMUXER,
285 };
286 
288  .class_name = "codec2raw demuxer",
289  .item_name = av_default_item_name,
290  .option = codec2raw_options,
291  .version = LIBAVUTIL_VERSION_INT,
292  .category = AV_CLASS_CATEGORY_DEMUXER,
293 };
294 
295 #if CONFIG_CODEC2_DEMUXER
297  .name = "codec2",
298  .long_name = NULL_IF_CONFIG_SMALL("codec2 .c2 demuxer"),
299  .priv_data_size = sizeof(Codec2Context),
300  .extensions = "c2",
306  .raw_codec_id = AV_CODEC_ID_CODEC2,
307  .priv_class = &codec2_demux_class,
308 };
309 #endif
310 
311 #if CONFIG_CODEC2_MUXER
313  .name = "codec2",
314  .long_name = NULL_IF_CONFIG_SMALL("codec2 .c2 muxer"),
315  .priv_data_size = sizeof(Codec2Context),
316  .extensions = "c2",
317  .audio_codec = AV_CODEC_ID_CODEC2,
318  .video_codec = AV_CODEC_ID_NONE,
322 };
323 #endif
324 
325 #if CONFIG_CODEC2RAW_DEMUXER
327  .name = "codec2raw",
328  .long_name = NULL_IF_CONFIG_SMALL("raw codec2 demuxer"),
329  .priv_data_size = sizeof(Codec2Context),
334  .raw_codec_id = AV_CODEC_ID_CODEC2,
335  .priv_class = &codec2raw_demux_class,
336 };
337 #endif
CODEC2_EXTRADATA_SIZE
#define CODEC2_EXTRADATA_SIZE
Definition: codec2utils.h:48
codec2_options
static const AVOption codec2_options[]
Definition: codec2.c:268
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
AVOutputFormat::name
const char * name
Definition: avformat.h:496
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:724
pcm.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
ff_codec2raw_demuxer
const AVInputFormat ff_codec2raw_demuxer
ffformatcontext
static av_always_inline FFFormatContext * ffformatcontext(AVFormatContext *s)
Definition: internal.h:183
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:90
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
EXPECTED_CODEC2_MINOR_VERSION
#define EXPECTED_CODEC2_MINOR_VERSION
Definition: codec2.c:39
codec2_read_packet
static int codec2_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: codec2.c:185
ff_codec2_muxer
const AVOutputFormat ff_codec2_muxer
AVOption
AVOption.
Definition: opt.h:247
codec2_write_header
static int codec2_write_header(AVFormatContext *s)
Definition: codec2.c:213
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:391
codec2_read_header_common
static int codec2_read_header_common(AVFormatContext *s, AVStream *st)
Definition: codec2.c:125
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
codec2_mode_bit_rate
static int codec2_mode_bit_rate(AVFormatContext *s, int mode)
Definition: codec2.c:113
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:149
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:626
AVCodecParameters::frame_size
int frame_size
Audio only.
Definition: codec_par.h:181
codec2_make_extradata
static void codec2_make_extradata(uint8_t *ptr, int mode)
Definition: codec2utils.h:51
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
EXPECTED_CODEC2_MAJOR_VERSION
#define EXPECTED_CODEC2_MAJOR_VERSION
Definition: codec2.c:38
CODEC2_MODE_MAX
#define CODEC2_MODE_MAX
Definition: codec2utils.h:30
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:631
codec2_read_header
static int codec2_read_header(AVFormatContext *s)
Definition: codec2.c:150
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
frame_size
int frame_size
Definition: mxfenc.c:2207
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
codec2utils.h
FFFormatContext::data_offset
int64_t data_offset
offset of the first packet
Definition: internal.h:93
ff_raw_write_packet
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:29
AV_CODEC_ID_CODEC2
@ AV_CODEC_ID_CODEC2
Definition: codec_id.h:489
AV_CLASS_CATEGORY_DEMUXER
@ AV_CLASS_CATEGORY_DEMUXER
Definition: log.h:33
AVFormatContext
Format I/O context.
Definition: avformat.h:1097
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:992
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
codec2raw_read_header
static int codec2raw_read_header(AVFormatContext *s)
Definition: codec2.c:236
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
Codec2Context::frames_per_packet
int frames_per_packet
Definition: codec2.c:44
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
avio_rb24
unsigned int avio_rb24(AVIOContext *s)
Definition: aviobuf.c:766
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
size
int size
Definition: twinvq_data.h:10344
avpriv_report_missing_feature
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:218
codec2_mode_from_extradata
static uint8_t codec2_mode_from_extradata(uint8_t *ptr)
Definition: codec2utils.h:59
version
version
Definition: libkvazaar.c:307
rawenc.h
write_packet
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
Definition: ffmpeg.c:731
codec2raw_demux_class
static const AVClass codec2raw_demux_class
Definition: codec2.c:287
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
AVOutputFormat
Definition: avformat.h:495
avio_internal.h
Codec2Context::mode
int mode
Definition: codec2.c:43
CODEC2_AVOPTIONS
#define CODEC2_AVOPTIONS(desc, classname, min_val, default_val, option_flags)
Definition: codec2utils.h:36
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
codec2_mode_block_align
static int codec2_mode_block_align(AVFormatContext *s, int mode)
Definition: codec2.c:89
AV_OPT_FLAG_DECODING_PARAM
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:278
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:61
FRAMES_PER_PACKET
#define FRAMES_PER_PACKET
Definition: codec2.c:264
codec2raw_options
static const AVOption codec2raw_options[]
Definition: codec2.c:273
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:196
codec2_mode_frame_size
static int codec2_mode_frame_size(AVFormatContext *s, int mode)
Definition: codec2.c:66
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:845
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
ff_pcm_read_seek
int ff_pcm_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: pcm.c:56
avformat.h
ff_codec2_demuxer
const AVInputFormat ff_codec2_demuxer
codec2_demux_class
static const AVClass codec2_demux_class
Definition: codec2.c:279
c2
static const uint64_t c2
Definition: murmur3.c:52
channel_layout.h
mode
mode
Definition: ebur128.h:83
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:1146
Codec2Context
Definition: codec2.c:41
CODEC2_MAGIC
#define CODEC2_MAGIC
Definition: codec2.c:34
AVCodecParameters::format
int format
Definition: codec_par.h:84
avio_wb24
void avio_wb24(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:469
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
codec2_probe
static int codec2_probe(const AVProbeData *p)
Definition: codec2.c:47
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecParameters::channel_layout
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ffio_read_size
int ffio_read_size(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:674
CODEC2_HEADER_SIZE
#define CODEC2_HEADER_SIZE
Definition: codec2.c:33
write_header
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:347
AV_RB24
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:97
AV_RB16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:98
ff_alloc_extradata
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0.
Definition: utils.c:451