FFmpeg
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ffmenc.c
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1 /*
2  * FFM (ffserver live feed) muxer
3  * Copyright (c) 2001 Fabrice Bellard
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 "libavutil/intreadwrite.h"
23 #include "libavutil/intfloat.h"
24 #include "libavutil/avassert.h"
25 #include "libavutil/parseutils.h"
26 #include "libavutil/opt.h"
27 #include "avformat.h"
28 #include "avio_internal.h"
29 #include "internal.h"
30 #include "ffm.h"
31 
33 {
34  FFMContext *ffm = s->priv_data;
35  int fill_size, h;
36  AVIOContext *pb = s->pb;
37 
38  fill_size = ffm->packet_end - ffm->packet_ptr;
39  memset(ffm->packet_ptr, 0, fill_size);
40 
41  av_assert1(avio_tell(pb) % ffm->packet_size == 0);
42 
43  /* put header */
44  avio_wb16(pb, PACKET_ID);
45  avio_wb16(pb, fill_size);
46  avio_wb64(pb, ffm->dts);
47  h = ffm->frame_offset;
48  if (ffm->first_packet)
49  h |= 0x8000;
50  avio_wb16(pb, h);
51  avio_write(pb, ffm->packet, ffm->packet_end - ffm->packet);
52  avio_flush(pb);
53 
54  /* prepare next packet */
55  ffm->frame_offset = 0; /* no key frame */
56  ffm->packet_ptr = ffm->packet;
57  ffm->first_packet = 0;
58 }
59 
60 /* 'first' is true if first data of a frame */
62  const uint8_t *buf, int size,
63  int64_t dts, int header)
64 {
65  FFMContext *ffm = s->priv_data;
66  int len;
67 
68  if (header && ffm->frame_offset == 0) {
69  ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
70  ffm->dts = dts;
71  }
72 
73  /* write as many packets as needed */
74  while (size > 0) {
75  len = ffm->packet_end - ffm->packet_ptr;
76  if (len > size)
77  len = size;
78  memcpy(ffm->packet_ptr, buf, len);
79 
80  ffm->packet_ptr += len;
81  buf += len;
82  size -= len;
83  if (ffm->packet_ptr >= ffm->packet_end)
84  flush_packet(s);
85  }
86 }
87 
88 static void write_header_chunk(AVIOContext *pb, AVIOContext *dpb, unsigned id)
89 {
90  uint8_t *dyn_buf;
91  int dyn_size= avio_close_dyn_buf(dpb, &dyn_buf);
92  avio_wb32(pb, id);
93  avio_wb32(pb, dyn_size);
94  avio_write(pb, dyn_buf, dyn_size);
95  av_free(dyn_buf);
96 }
97 
98 static int ffm_write_header_codec_ctx(AVIOContext *pb, AVCodecParameters *ctxpar, unsigned tag, int type)
99 {
100  AVIOContext *tmp;
101  char *buf = NULL;
102  int ret, need_coma = 0;
104 
105 #define SKIP_DEFAULTS AV_OPT_SERIALIZE_SKIP_DEFAULTS
106 #define OPT_FLAGS_EXACT AV_OPT_SERIALIZE_OPT_FLAGS_EXACT
107 #define ENC AV_OPT_FLAG_ENCODING_PARAM
108 
109  if (avio_open_dyn_buf(&tmp) < 0)
110  return AVERROR(ENOMEM);
111 
112  // AVCodecParameters does not suport AVOptions, we thus must copy it over to a context that does
113  // otherwise it could be used directly and this would be much simpler
115  if (!ctx) {
116  ret = AVERROR(ENOMEM);
117  goto fail;
118  }
119  avcodec_parameters_to_context(ctx, ctxpar);
120 
121  if ((ret = av_opt_serialize(ctx, ENC | type, SKIP_DEFAULTS, &buf, '=', ',')) < 0)
122  goto fail;
123  if (buf && strlen(buf)) {
124  avio_write(tmp, buf, strlen(buf));
125  av_freep(&buf);
126  need_coma = 1;
127  }
128  if ((ret = av_opt_serialize(ctx, 0, SKIP_DEFAULTS | OPT_FLAGS_EXACT, &buf, '=', ',')) < 0)
129  goto fail;
130  if (buf && strlen(buf)) {
131  if (need_coma)
132  avio_w8(tmp, ',');
133  avio_write(tmp, buf, strlen(buf));
134  }
135  av_freep(&buf);
136  avio_w8(tmp, 0);
137  write_header_chunk(pb, tmp, tag);
138  avcodec_free_context(&ctx);
139  return 0;
140  fail:
141  av_free(buf);
142  ffio_free_dyn_buf(&tmp);
143  avcodec_free_context(&ctx);
144  return ret;
145 
146 #undef SKIP_DEFAULTS
147 #undef OPT_FLAGS_EXACT
148 #undef ENC
149 }
150 
151 static int ffm_write_recommended_config(AVIOContext *pb, AVCodecParameters *codecpar, unsigned tag,
152  const char *configuration)
153 {
154  int ret;
155  const AVCodec *enc = avcodec_find_encoder(codecpar->codec_id);
156  AVIOContext *tmp;
157  AVDictionaryEntry *t = NULL;
158  AVDictionary *all = NULL, *comm = NULL, *prv = NULL;
159  char *buf = NULL;
160 
161  if (!enc || !enc->priv_class || !enc->priv_data_size) {
162  /* codec is not known/has no private options, so save everything as common options */
163  if (avio_open_dyn_buf(&tmp) < 0)
164  return AVERROR(ENOMEM);
165  avio_put_str(tmp, configuration);
166  write_header_chunk(pb, tmp, tag);
167  return 0;
168  }
169 
170  if ((ret = av_dict_parse_string(&all, configuration, "=", ",", 0)) < 0)
171  return ret;
172 
173  while ((t = av_dict_get(all, "", t, AV_DICT_IGNORE_SUFFIX))) {
174  if (av_opt_find((void *)&enc->priv_class, t->key, NULL, 0, AV_OPT_SEARCH_FAKE_OBJ)) {
175  if ((ret = av_dict_set(&prv, t->key, t->value, 0)) < 0)
176  goto fail;
177  } else if ((ret = av_dict_set(&comm, t->key, t->value, 0)) < 0)
178  goto fail;
179  }
180 
181  if (comm) {
182  if ((ret = av_dict_get_string(comm, &buf, '=', ',')) < 0 ||
183  (ret = avio_open_dyn_buf(&tmp)) < 0)
184  goto fail;
185  avio_put_str(tmp, buf);
186  av_freep(&buf);
187  write_header_chunk(pb, tmp, tag);
188  }
189  if (prv) {
190  if ((ret = av_dict_get_string(prv, &buf, '=', ',')) < 0 ||
191  (ret = avio_open_dyn_buf(&tmp)) < 0)
192  goto fail;
193  avio_put_str(tmp, buf);
194  write_header_chunk(pb, tmp, MKBETAG('C', 'P', 'R', 'V'));
195  }
196 
197  fail:
198  av_free(buf);
199  av_dict_free(&all);
200  av_dict_free(&comm);
201  av_dict_free(&prv);
202  return ret;
203 }
204 
206 {
207  FFMContext *ffm = s->priv_data;
208  AVStream *st;
209  AVIOContext *pb = s->pb;
210  AVCodecParameters *codecpar;
211  int bit_rate, i, ret;
212 
213  if ((ret = ff_parse_creation_time_metadata(s, &ffm->start_time, 0)) < 0)
214  return ret;
215 
217 
218  /* header */
219  avio_wl32(pb, MKTAG('F', 'F', 'M', '2'));
220  avio_wb32(pb, ffm->packet_size);
221  avio_wb64(pb, 0); /* current write position */
222 
223  if(avio_open_dyn_buf(&pb) < 0)
224  return AVERROR(ENOMEM);
225 
226  avio_wb32(pb, s->nb_streams);
227  bit_rate = 0;
228  for(i=0;i<s->nb_streams;i++) {
229  st = s->streams[i];
230  bit_rate += st->codecpar->bit_rate;
231  }
232  avio_wb32(pb, bit_rate);
233 
234  write_header_chunk(s->pb, pb, MKBETAG('M', 'A', 'I', 'N'));
235 
236  /* list of streams */
237  for(i=0;i<s->nb_streams;i++) {
238  int flags = 0;
239  st = s->streams[i];
240  avpriv_set_pts_info(st, 64, 1, 1000000);
241  if(avio_open_dyn_buf(&pb) < 0)
242  return AVERROR(ENOMEM);
243 
244  codecpar = st->codecpar;
245  /* generic info */
246  avio_wb32(pb, codecpar->codec_id);
247  avio_w8(pb, codecpar->codec_type);
248  avio_wb32(pb, codecpar->bit_rate);
249  if (codecpar->extradata_size)
251 
252  // If the user is not providing us with a configuration we have to fill it in as we cannot access the encoder
254  if (s->flags & AVFMT_FLAG_BITEXACT)
255  flags |= AV_CODEC_FLAG_BITEXACT;
256  }
257 
258  avio_wb32(pb, flags);
259  avio_wb32(pb, 0); // flags2
260  avio_wb32(pb, 0); // debug
261  if (codecpar->extradata_size) {
262  avio_wb32(pb, codecpar->extradata_size);
263  avio_write(pb, codecpar->extradata, codecpar->extradata_size);
264  }
265  write_header_chunk(s->pb, pb, MKBETAG('C', 'O', 'M', 'M'));
266  /* specific info */
267  switch(codecpar->codec_type) {
268  case AVMEDIA_TYPE_VIDEO:
270  av_log(NULL, AV_LOG_DEBUG, "writing recommended configuration: %s\n",
272  if ((ret = ffm_write_recommended_config(s->pb, codecpar, MKBETAG('S', '2', 'V', 'I'),
274  return ret;
275  } else if ((ret = ffm_write_header_codec_ctx(s->pb, codecpar, MKBETAG('S', '2', 'V', 'I'), AV_OPT_FLAG_VIDEO_PARAM)) < 0)
276  return ret;
277  break;
278  case AVMEDIA_TYPE_AUDIO:
280  av_log(NULL, AV_LOG_DEBUG, "writing recommended configuration: %s\n",
282  if ((ret = ffm_write_recommended_config(s->pb, codecpar, MKBETAG('S', '2', 'A', 'U'),
284  return ret;
285  } else if ((ret = ffm_write_header_codec_ctx(s->pb, codecpar, MKBETAG('S', '2', 'A', 'U'), AV_OPT_FLAG_AUDIO_PARAM)) < 0)
286  return ret;
287  break;
288  default:
289  return -1;
290  }
291  }
292  pb = s->pb;
293 
294  avio_wb64(pb, 0); // end of header
295 
296  /* flush until end of block reached */
297  while ((avio_tell(pb) % ffm->packet_size) != 0)
298  avio_w8(pb, 0);
299 
300  avio_flush(pb);
301 
302  /* init packet mux */
303  ffm->packet_ptr = ffm->packet;
304  ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
305  av_assert0(ffm->packet_end >= ffm->packet);
306  ffm->frame_offset = 0;
307  ffm->dts = 0;
308  ffm->first_packet = 1;
309 
310  return 0;
311 }
312 
314 {
315  FFMContext *ffm = s->priv_data;
316  int64_t dts;
318  int header_size = FRAME_HEADER_SIZE;
319 
320  dts = ffm->start_time + pkt->dts;
321  /* packet size & key_frame */
322  header[0] = pkt->stream_index;
323  header[1] = 0;
324  if (pkt->flags & AV_PKT_FLAG_KEY)
325  header[1] |= FLAG_KEY_FRAME;
326  AV_WB24(header+2, pkt->size);
327  AV_WB24(header+5, pkt->duration);
328  AV_WB64(header+8, ffm->start_time + pkt->pts);
329  if (pkt->pts != pkt->dts) {
330  header[1] |= FLAG_DTS;
331  AV_WB32(header+16, pkt->pts - pkt->dts);
332  header_size += 4;
333  }
334  ffm_write_data(s, header, header_size, dts, 1);
335  ffm_write_data(s, pkt->data, pkt->size, dts, 0);
336 
337  return 0;
338 }
339 
341 {
342  FFMContext *ffm = s->priv_data;
343 
344  /* flush packets */
345  if (ffm->packet_ptr > ffm->packet)
346  flush_packet(s);
347 
348  return 0;
349 }
350 
352  .name = "ffm",
353  .long_name = NULL_IF_CONFIG_SMALL("FFM (FFserver live feed)"),
354  .extensions = "ffm",
355  .priv_data_size = sizeof(FFMContext),
356  .audio_codec = AV_CODEC_ID_MP2,
357  .video_codec = AV_CODEC_ID_MPEG1VIDEO,
362 };
void avio_wb64(AVIOContext *s, uint64_t val)
Definition: aviobuf.c:440
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:147
#define PACKET_ID
Definition: ffm.h:32
int64_t dts
Definition: ffm.h:55
char * recommended_encoder_configuration
String containing paris of key and values describing recommended encoder configuration.
Definition: avformat.h:1215
AVCodec * avcodec_find_encoder(enum AVCodecID id)
Find a registered encoder with a matching codec ID.
Definition: utils.c:3108
int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
Return the written size and a pointer to the buffer.
Definition: aviobuf.c:1280
int frame_offset
Definition: ffm.h:54
void avpriv_set_pts_info(AVStream *s, 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:4581
#define FFM_PACKET_SIZE
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3981
#define AV_OPT_FLAG_AUDIO_PARAM
Definition: opt.h:281
int size
Definition: avcodec.h:1602
int av_dict_get_string(const AVDictionary *m, char **buffer, const char key_val_sep, const char pairs_sep)
Get dictionary entries as a string.
Definition: dict.c:230
static AVPacket pkt
int av_opt_serialize(void *obj, int opt_flags, int flags, char **buffer, const char key_val_sep, const char pairs_sep)
Serialize object's options.
Definition: opt.c:1982
#define FLAG_DTS
Definition: ffm.h:37
AVCodec.
Definition: avcodec.h:3601
int avio_open_dyn_buf(AVIOContext **s)
Open a write only memory stream.
Definition: aviobuf.c:1268
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3973
#define FFM_HEADER_SIZE
Definition: ffm.h:30
Format I/O context.
Definition: avformat.h:1338
#define AV_WB64(p, v)
Definition: intreadwrite.h:433
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
#define OPT_FLAGS_EXACT
static void write_header_chunk(AVIOContext *pb, AVIOContext *dpb, unsigned id)
Definition: ffmenc.c:88
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:346
uint8_t
static void ffm_write_data(AVFormatContext *s, const uint8_t *buf, int size, int64_t dts, int header)
Definition: ffmenc.c:61
AVOptions.
#define FRAME_HEADER_SIZE
Definition: cpia.c:30
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1619
uint8_t * packet_end
Definition: ffm.h:56
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1406
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: utils.c:4223
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:40
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1449
uint8_t * data
Definition: avcodec.h:1601
static int flags
Definition: log.c:57
uint32_t tag
Definition: movenc.c:1412
#define ENC
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:511
static const uint8_t header[24]
Definition: sdr2.c:67
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:204
#define AVFMT_FLAG_BITEXACT
When muxing, try to avoid writing any random/volatile data to the output.
Definition: avformat.h:1466
#define av_log(a,...)
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:4010
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1633
static int ffm_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: ffmenc.c:313
static int ffm_write_header_codec_ctx(AVIOContext *pb, AVCodecParameters *ctxpar, unsigned tag, int type)
Definition: ffmenc.c:98
uint8_t * packet_ptr
Definition: ffm.h:56
int ff_parse_creation_time_metadata(AVFormatContext *s, int64_t *timestamp, int return_seconds)
Parse creation_time in AVFormatContext metadata if exists and warn if the parsing fails...
Definition: utils.c:5300
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:203
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3977
simple assert() macros that are a bit more flexible than ISO C assert().
#define fail()
Definition: checkasm.h:84
int first_packet
Definition: ffm.h:52
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1607
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3999
static int ffm_write_trailer(AVFormatContext *s)
Definition: ffmenc.c:340
const AVOption * av_opt_find(void *obj, const char *name, const char *unit, int opt_flags, int search_flags)
Look for an option in an object.
Definition: opt.c:1596
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1394
static void flush_packet(AVFormatContext *s)
Definition: ffmenc.c:32
int void avio_flush(AVIOContext *s)
Force flushing of buffered data.
Definition: aviobuf.c:224
#define AV_CODEC_FLAG_BITEXACT
Use only bitexact stuff (except (I)DCT).
Definition: avcodec.h:886
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:156
static int ffm_write_header(AVFormatContext *s)
Definition: ffmenc.c:205
int64_t start_time
Definition: ffm.h:58
int priv_data_size
Definition: avcodec.h:3637
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:94
const char * name
Definition: avformat.h:524
AVFormatContext * ctx
Definition: movenc.c:48
#define SKIP_DEFAULTS
#define AV_WB24(p, d)
Definition: intreadwrite.h:450
int packet_size
Definition: ffm.h:53
void ffio_free_dyn_buf(AVIOContext **s)
Free a dynamic buffer.
Definition: aviobuf.c:1308
int avio_put_str(AVIOContext *s, const char *str)
Write a NULL-terminated string.
Definition: aviobuf.c:362
Stream structure.
Definition: avformat.h:889
int av_dict_parse_string(AVDictionary **pm, const char *str, const char *key_val_sep, const char *pairs_sep, int flags)
Parse the key/value pairs list and add the parsed entries to a dictionary.
Definition: dict.c:180
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer...
Definition: options.c:171
AVIOContext * pb
I/O context.
Definition: avformat.h:1380
Definition: ffm.h:44
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:182
#define AV_OPT_FLAG_VIDEO_PARAM
Definition: opt.h:282
main external API structure.
Definition: avcodec.h:1676
void * buf
Definition: avisynth_c.h:690
GLint GLenum type
Definition: opengl_enc.c:105
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost)
Definition: ffmpeg.c:650
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
misc parsing utilities
AVOutputFormat ff_ffm_muxer
Definition: ffmenc.c:351
void avio_wb16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:452
const AVClass * priv_class
AVClass for the private context.
Definition: avcodec.h:3627
#define AV_CODEC_FLAG_GLOBAL_HEADER
Place global headers in extradata instead of every keyframe.
Definition: avcodec.h:882
Main libavformat public API header.
uint8_t packet[FFM_PACKET_SIZE]
Definition: ffm.h:57
static int ffm_write_recommended_config(AVIOContext *pb, AVCodecParameters *codecpar, unsigned tag, const char *configuration)
Definition: ffmenc.c:151
#define AV_OPT_SEARCH_FAKE_OBJ
The obj passed to av_opt_find() is fake – only a double pointer to AVClass instead of a required poin...
Definition: opt.h:566
char * key
Definition: dict.h:86
#define MKBETAG(a, b, c, d)
Definition: common.h:343
#define av_free(p)
char * value
Definition: dict.h:87
int len
static uint8_t tmp[8]
Definition: des.c:38
void * priv_data
Format private data.
Definition: avformat.h:1366
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:344
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3995
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1600
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:354
#define av_freep(p)
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key, ignoring the suffix of the found key string.
Definition: dict.h:70
AVCodecParameters * codecpar
Definition: avformat.h:1241
int stream_index
Definition: avcodec.h:1603
#define MKTAG(a, b, c, d)
Definition: common.h:342
#define AVFMT_TS_NEGATIVE
Format allows muxing negative timestamps.
Definition: avformat.h:501
This structure stores compressed data.
Definition: avcodec.h:1578
#define FLAG_KEY_FRAME
Definition: ffm.h:36
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1594