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muxing.c
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1 /*
2  * Copyright (c) 2003 Fabrice Bellard
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a copy
5  * of this software and associated documentation files (the "Software"), to deal
6  * in the Software without restriction, including without limitation the rights
7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8  * copies of the Software, and to permit persons to whom the Software is
9  * furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
20  * THE SOFTWARE.
21  */
22 
23 /**
24  * @file
25  * libavformat API example.
26  *
27  * Output a media file in any supported libavformat format. The default
28  * codecs are used.
29  * @example muxing.c
30  */
31 
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <string.h>
35 #include <math.h>
36 
37 #include <libavutil/avassert.h>
39 #include <libavutil/opt.h>
40 #include <libavutil/mathematics.h>
41 #include <libavutil/timestamp.h>
42 #include <libavformat/avformat.h>
43 #include <libswscale/swscale.h>
45 
46 #define STREAM_DURATION 10.0
47 #define STREAM_FRAME_RATE 25 /* 25 images/s */
48 #define STREAM_PIX_FMT AV_PIX_FMT_YUV420P /* default pix_fmt */
49 
50 #define SCALE_FLAGS SWS_BICUBIC
51 
52 // a wrapper around a single output AVStream
53 typedef struct OutputStream {
56 
57  /* pts of the next frame that will be generated */
58  int64_t next_pts;
60 
63 
64  float t, tincr, tincr2;
65 
68 } OutputStream;
69 
70 static void log_packet(const AVFormatContext *fmt_ctx, const AVPacket *pkt)
71 {
72  AVRational *time_base = &fmt_ctx->streams[pkt->stream_index]->time_base;
73 
74  printf("pts:%s pts_time:%s dts:%s dts_time:%s duration:%s duration_time:%s stream_index:%d\n",
75  av_ts2str(pkt->pts), av_ts2timestr(pkt->pts, time_base),
76  av_ts2str(pkt->dts), av_ts2timestr(pkt->dts, time_base),
77  av_ts2str(pkt->duration), av_ts2timestr(pkt->duration, time_base),
78  pkt->stream_index);
79 }
80 
81 static int write_frame(AVFormatContext *fmt_ctx, const AVRational *time_base, AVStream *st, AVPacket *pkt)
82 {
83  /* rescale output packet timestamp values from codec to stream timebase */
84  av_packet_rescale_ts(pkt, *time_base, st->time_base);
85  pkt->stream_index = st->index;
86 
87  /* Write the compressed frame to the media file. */
88  log_packet(fmt_ctx, pkt);
89  return av_interleaved_write_frame(fmt_ctx, pkt);
90 }
91 
92 /* Add an output stream. */
93 static void add_stream(OutputStream *ost, AVFormatContext *oc,
94  AVCodec **codec,
95  enum AVCodecID codec_id)
96 {
98  int i;
99 
100  /* find the encoder */
101  *codec = avcodec_find_encoder(codec_id);
102  if (!(*codec)) {
103  fprintf(stderr, "Could not find encoder for '%s'\n",
104  avcodec_get_name(codec_id));
105  exit(1);
106  }
107 
108  ost->st = avformat_new_stream(oc, NULL);
109  if (!ost->st) {
110  fprintf(stderr, "Could not allocate stream\n");
111  exit(1);
112  }
113  ost->st->id = oc->nb_streams-1;
114  c = avcodec_alloc_context3(*codec);
115  if (!c) {
116  fprintf(stderr, "Could not alloc an encoding context\n");
117  exit(1);
118  }
119  ost->enc = c;
120 
121  switch ((*codec)->type) {
122  case AVMEDIA_TYPE_AUDIO:
123  c->sample_fmt = (*codec)->sample_fmts ?
124  (*codec)->sample_fmts[0] : AV_SAMPLE_FMT_FLTP;
125  c->bit_rate = 64000;
126  c->sample_rate = 44100;
127  if ((*codec)->supported_samplerates) {
128  c->sample_rate = (*codec)->supported_samplerates[0];
129  for (i = 0; (*codec)->supported_samplerates[i]; i++) {
130  if ((*codec)->supported_samplerates[i] == 44100)
131  c->sample_rate = 44100;
132  }
133  }
136  if ((*codec)->channel_layouts) {
137  c->channel_layout = (*codec)->channel_layouts[0];
138  for (i = 0; (*codec)->channel_layouts[i]; i++) {
139  if ((*codec)->channel_layouts[i] == AV_CH_LAYOUT_STEREO)
141  }
142  }
144  ost->st->time_base = (AVRational){ 1, c->sample_rate };
145  break;
146 
147  case AVMEDIA_TYPE_VIDEO:
148  c->codec_id = codec_id;
149 
150  c->bit_rate = 400000;
151  /* Resolution must be a multiple of two. */
152  c->width = 352;
153  c->height = 288;
154  /* timebase: This is the fundamental unit of time (in seconds) in terms
155  * of which frame timestamps are represented. For fixed-fps content,
156  * timebase should be 1/framerate and timestamp increments should be
157  * identical to 1. */
158  ost->st->time_base = (AVRational){ 1, STREAM_FRAME_RATE };
159  c->time_base = ost->st->time_base;
160 
161  c->gop_size = 12; /* emit one intra frame every twelve frames at most */
162  c->pix_fmt = STREAM_PIX_FMT;
163  if (c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
164  /* just for testing, we also add B frames */
165  c->max_b_frames = 2;
166  }
167  if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
168  /* Needed to avoid using macroblocks in which some coeffs overflow.
169  * This does not happen with normal video, it just happens here as
170  * the motion of the chroma plane does not match the luma plane. */
171  c->mb_decision = 2;
172  }
173  break;
174 
175  default:
176  break;
177  }
178 
179  /* Some formats want stream headers to be separate. */
180  if (oc->oformat->flags & AVFMT_GLOBALHEADER)
182 }
183 
184 /**************************************************************/
185 /* audio output */
186 
187 static AVFrame *alloc_audio_frame(enum AVSampleFormat sample_fmt,
188  uint64_t channel_layout,
189  int sample_rate, int nb_samples)
190 {
192  int ret;
193 
194  if (!frame) {
195  fprintf(stderr, "Error allocating an audio frame\n");
196  exit(1);
197  }
198 
199  frame->format = sample_fmt;
200  frame->channel_layout = channel_layout;
201  frame->sample_rate = sample_rate;
202  frame->nb_samples = nb_samples;
203 
204  if (nb_samples) {
205  ret = av_frame_get_buffer(frame, 0);
206  if (ret < 0) {
207  fprintf(stderr, "Error allocating an audio buffer\n");
208  exit(1);
209  }
210  }
211 
212  return frame;
213 }
214 
215 static void open_audio(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
216 {
217  AVCodecContext *c;
218  int nb_samples;
219  int ret;
220  AVDictionary *opt = NULL;
221 
222  c = ost->enc;
223 
224  /* open it */
225  av_dict_copy(&opt, opt_arg, 0);
226  ret = avcodec_open2(c, codec, &opt);
227  av_dict_free(&opt);
228  if (ret < 0) {
229  fprintf(stderr, "Could not open audio codec: %s\n", av_err2str(ret));
230  exit(1);
231  }
232 
233  /* init signal generator */
234  ost->t = 0;
235  ost->tincr = 2 * M_PI * 110.0 / c->sample_rate;
236  /* increment frequency by 110 Hz per second */
237  ost->tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate;
238 
240  nb_samples = 10000;
241  else
242  nb_samples = c->frame_size;
243 
245  c->sample_rate, nb_samples);
247  c->sample_rate, nb_samples);
248 
249  /* copy the stream parameters to the muxer */
251  if (ret < 0) {
252  fprintf(stderr, "Could not copy the stream parameters\n");
253  exit(1);
254  }
255 
256  /* create resampler context */
257  ost->swr_ctx = swr_alloc();
258  if (!ost->swr_ctx) {
259  fprintf(stderr, "Could not allocate resampler context\n");
260  exit(1);
261  }
262 
263  /* set options */
264  av_opt_set_int (ost->swr_ctx, "in_channel_count", c->channels, 0);
265  av_opt_set_int (ost->swr_ctx, "in_sample_rate", c->sample_rate, 0);
266  av_opt_set_sample_fmt(ost->swr_ctx, "in_sample_fmt", AV_SAMPLE_FMT_S16, 0);
267  av_opt_set_int (ost->swr_ctx, "out_channel_count", c->channels, 0);
268  av_opt_set_int (ost->swr_ctx, "out_sample_rate", c->sample_rate, 0);
269  av_opt_set_sample_fmt(ost->swr_ctx, "out_sample_fmt", c->sample_fmt, 0);
270 
271  /* initialize the resampling context */
272  if ((ret = swr_init(ost->swr_ctx)) < 0) {
273  fprintf(stderr, "Failed to initialize the resampling context\n");
274  exit(1);
275  }
276 }
277 
278 /* Prepare a 16 bit dummy audio frame of 'frame_size' samples and
279  * 'nb_channels' channels. */
281 {
282  AVFrame *frame = ost->tmp_frame;
283  int j, i, v;
284  int16_t *q = (int16_t*)frame->data[0];
285 
286  /* check if we want to generate more frames */
287  if (av_compare_ts(ost->next_pts, ost->enc->time_base,
288  STREAM_DURATION, (AVRational){ 1, 1 }) >= 0)
289  return NULL;
290 
291  for (j = 0; j <frame->nb_samples; j++) {
292  v = (int)(sin(ost->t) * 10000);
293  for (i = 0; i < ost->enc->channels; i++)
294  *q++ = v;
295  ost->t += ost->tincr;
296  ost->tincr += ost->tincr2;
297  }
298 
299  frame->pts = ost->next_pts;
300  ost->next_pts += frame->nb_samples;
301 
302  return frame;
303 }
304 
305 /*
306  * encode one audio frame and send it to the muxer
307  * return 1 when encoding is finished, 0 otherwise
308  */
310 {
311  AVCodecContext *c;
312  AVPacket pkt = { 0 }; // data and size must be 0;
313  AVFrame *frame;
314  int ret;
315  int got_packet;
316  int dst_nb_samples;
317 
318  av_init_packet(&pkt);
319  c = ost->enc;
320 
321  frame = get_audio_frame(ost);
322 
323  if (frame) {
324  /* convert samples from native format to destination codec format, using the resampler */
325  /* compute destination number of samples */
326  dst_nb_samples = av_rescale_rnd(swr_get_delay(ost->swr_ctx, c->sample_rate) + frame->nb_samples,
328  av_assert0(dst_nb_samples == frame->nb_samples);
329 
330  /* when we pass a frame to the encoder, it may keep a reference to it
331  * internally;
332  * make sure we do not overwrite it here
333  */
334  ret = av_frame_make_writable(ost->frame);
335  if (ret < 0)
336  exit(1);
337 
338  /* convert to destination format */
339  ret = swr_convert(ost->swr_ctx,
340  ost->frame->data, dst_nb_samples,
341  (const uint8_t **)frame->data, frame->nb_samples);
342  if (ret < 0) {
343  fprintf(stderr, "Error while converting\n");
344  exit(1);
345  }
346  frame = ost->frame;
347 
348  frame->pts = av_rescale_q(ost->samples_count, (AVRational){1, c->sample_rate}, c->time_base);
349  ost->samples_count += dst_nb_samples;
350  }
351 
352  ret = avcodec_encode_audio2(c, &pkt, frame, &got_packet);
353  if (ret < 0) {
354  fprintf(stderr, "Error encoding audio frame: %s\n", av_err2str(ret));
355  exit(1);
356  }
357 
358  if (got_packet) {
359  ret = write_frame(oc, &c->time_base, ost->st, &pkt);
360  if (ret < 0) {
361  fprintf(stderr, "Error while writing audio frame: %s\n",
362  av_err2str(ret));
363  exit(1);
364  }
365  }
366 
367  return (frame || got_packet) ? 0 : 1;
368 }
369 
370 /**************************************************************/
371 /* video output */
372 
374 {
375  AVFrame *picture;
376  int ret;
377 
378  picture = av_frame_alloc();
379  if (!picture)
380  return NULL;
381 
382  picture->format = pix_fmt;
383  picture->width = width;
384  picture->height = height;
385 
386  /* allocate the buffers for the frame data */
387  ret = av_frame_get_buffer(picture, 32);
388  if (ret < 0) {
389  fprintf(stderr, "Could not allocate frame data.\n");
390  exit(1);
391  }
392 
393  return picture;
394 }
395 
396 static void open_video(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
397 {
398  int ret;
399  AVCodecContext *c = ost->enc;
400  AVDictionary *opt = NULL;
401 
402  av_dict_copy(&opt, opt_arg, 0);
403 
404  /* open the codec */
405  ret = avcodec_open2(c, codec, &opt);
406  av_dict_free(&opt);
407  if (ret < 0) {
408  fprintf(stderr, "Could not open video codec: %s\n", av_err2str(ret));
409  exit(1);
410  }
411 
412  /* allocate and init a re-usable frame */
413  ost->frame = alloc_picture(c->pix_fmt, c->width, c->height);
414  if (!ost->frame) {
415  fprintf(stderr, "Could not allocate video frame\n");
416  exit(1);
417  }
418 
419  /* If the output format is not YUV420P, then a temporary YUV420P
420  * picture is needed too. It is then converted to the required
421  * output format. */
422  ost->tmp_frame = NULL;
423  if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
425  if (!ost->tmp_frame) {
426  fprintf(stderr, "Could not allocate temporary picture\n");
427  exit(1);
428  }
429  }
430 
431  /* copy the stream parameters to the muxer */
433  if (ret < 0) {
434  fprintf(stderr, "Could not copy the stream parameters\n");
435  exit(1);
436  }
437 }
438 
439 /* Prepare a dummy image. */
440 static void fill_yuv_image(AVFrame *pict, int frame_index,
441  int width, int height)
442 {
443  int x, y, i, ret;
444 
445  /* when we pass a frame to the encoder, it may keep a reference to it
446  * internally;
447  * make sure we do not overwrite it here
448  */
449  ret = av_frame_make_writable(pict);
450  if (ret < 0)
451  exit(1);
452 
453  i = frame_index;
454 
455  /* Y */
456  for (y = 0; y < height; y++)
457  for (x = 0; x < width; x++)
458  pict->data[0][y * pict->linesize[0] + x] = x + y + i * 3;
459 
460  /* Cb and Cr */
461  for (y = 0; y < height / 2; y++) {
462  for (x = 0; x < width / 2; x++) {
463  pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
464  pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
465  }
466  }
467 }
468 
470 {
471  AVCodecContext *c = ost->enc;
472 
473  /* check if we want to generate more frames */
474  if (av_compare_ts(ost->next_pts, c->time_base,
475  STREAM_DURATION, (AVRational){ 1, 1 }) >= 0)
476  return NULL;
477 
478  if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
479  /* as we only generate a YUV420P picture, we must convert it
480  * to the codec pixel format if needed */
481  if (!ost->sws_ctx) {
482  ost->sws_ctx = sws_getContext(c->width, c->height,
484  c->width, c->height,
485  c->pix_fmt,
487  if (!ost->sws_ctx) {
488  fprintf(stderr,
489  "Could not initialize the conversion context\n");
490  exit(1);
491  }
492  }
493  fill_yuv_image(ost->tmp_frame, ost->next_pts, c->width, c->height);
494  sws_scale(ost->sws_ctx,
495  (const uint8_t * const *)ost->tmp_frame->data, ost->tmp_frame->linesize,
496  0, c->height, ost->frame->data, ost->frame->linesize);
497  } else {
498  fill_yuv_image(ost->frame, ost->next_pts, c->width, c->height);
499  }
500 
501  ost->frame->pts = ost->next_pts++;
502 
503  return ost->frame;
504 }
505 
506 /*
507  * encode one video frame and send it to the muxer
508  * return 1 when encoding is finished, 0 otherwise
509  */
511 {
512  int ret;
513  AVCodecContext *c;
514  AVFrame *frame;
515  int got_packet = 0;
516  AVPacket pkt = { 0 };
517 
518  c = ost->enc;
519 
520  frame = get_video_frame(ost);
521 
522  av_init_packet(&pkt);
523 
524  /* encode the image */
525  ret = avcodec_encode_video2(c, &pkt, frame, &got_packet);
526  if (ret < 0) {
527  fprintf(stderr, "Error encoding video frame: %s\n", av_err2str(ret));
528  exit(1);
529  }
530 
531  if (got_packet) {
532  ret = write_frame(oc, &c->time_base, ost->st, &pkt);
533  } else {
534  ret = 0;
535  }
536 
537  if (ret < 0) {
538  fprintf(stderr, "Error while writing video frame: %s\n", av_err2str(ret));
539  exit(1);
540  }
541 
542  return (frame || got_packet) ? 0 : 1;
543 }
544 
546 {
547  avcodec_free_context(&ost->enc);
548  av_frame_free(&ost->frame);
549  av_frame_free(&ost->tmp_frame);
550  sws_freeContext(ost->sws_ctx);
551  swr_free(&ost->swr_ctx);
552 }
553 
554 /**************************************************************/
555 /* media file output */
556 
557 int main(int argc, char **argv)
558 {
559  OutputStream video_st = { 0 }, audio_st = { 0 };
560  const char *filename;
562  AVFormatContext *oc;
563  AVCodec *audio_codec, *video_codec;
564  int ret;
565  int have_video = 0, have_audio = 0;
566  int encode_video = 0, encode_audio = 0;
567  AVDictionary *opt = NULL;
568  int i;
569 
570  /* Initialize libavcodec, and register all codecs and formats. */
571  av_register_all();
572 
573  if (argc < 2) {
574  printf("usage: %s output_file\n"
575  "API example program to output a media file with libavformat.\n"
576  "This program generates a synthetic audio and video stream, encodes and\n"
577  "muxes them into a file named output_file.\n"
578  "The output format is automatically guessed according to the file extension.\n"
579  "Raw images can also be output by using '%%d' in the filename.\n"
580  "\n", argv[0]);
581  return 1;
582  }
583 
584  filename = argv[1];
585  for (i = 2; i+1 < argc; i+=2) {
586  if (!strcmp(argv[i], "-flags") || !strcmp(argv[i], "-fflags"))
587  av_dict_set(&opt, argv[i]+1, argv[i+1], 0);
588  }
589 
590  /* allocate the output media context */
591  avformat_alloc_output_context2(&oc, NULL, NULL, filename);
592  if (!oc) {
593  printf("Could not deduce output format from file extension: using MPEG.\n");
594  avformat_alloc_output_context2(&oc, NULL, "mpeg", filename);
595  }
596  if (!oc)
597  return 1;
598 
599  fmt = oc->oformat;
600 
601  /* Add the audio and video streams using the default format codecs
602  * and initialize the codecs. */
603  if (fmt->video_codec != AV_CODEC_ID_NONE) {
604  add_stream(&video_st, oc, &video_codec, fmt->video_codec);
605  have_video = 1;
606  encode_video = 1;
607  }
608  if (fmt->audio_codec != AV_CODEC_ID_NONE) {
609  add_stream(&audio_st, oc, &audio_codec, fmt->audio_codec);
610  have_audio = 1;
611  encode_audio = 1;
612  }
613 
614  /* Now that all the parameters are set, we can open the audio and
615  * video codecs and allocate the necessary encode buffers. */
616  if (have_video)
617  open_video(oc, video_codec, &video_st, opt);
618 
619  if (have_audio)
620  open_audio(oc, audio_codec, &audio_st, opt);
621 
622  av_dump_format(oc, 0, filename, 1);
623 
624  /* open the output file, if needed */
625  if (!(fmt->flags & AVFMT_NOFILE)) {
626  ret = avio_open(&oc->pb, filename, AVIO_FLAG_WRITE);
627  if (ret < 0) {
628  fprintf(stderr, "Could not open '%s': %s\n", filename,
629  av_err2str(ret));
630  return 1;
631  }
632  }
633 
634  /* Write the stream header, if any. */
635  ret = avformat_write_header(oc, &opt);
636  if (ret < 0) {
637  fprintf(stderr, "Error occurred when opening output file: %s\n",
638  av_err2str(ret));
639  return 1;
640  }
641 
642  while (encode_video || encode_audio) {
643  /* select the stream to encode */
644  if (encode_video &&
645  (!encode_audio || av_compare_ts(video_st.next_pts, video_st.enc->time_base,
646  audio_st.next_pts, audio_st.enc->time_base) <= 0)) {
647  encode_video = !write_video_frame(oc, &video_st);
648  } else {
649  encode_audio = !write_audio_frame(oc, &audio_st);
650  }
651  }
652 
653  /* Write the trailer, if any. The trailer must be written before you
654  * close the CodecContexts open when you wrote the header; otherwise
655  * av_write_trailer() may try to use memory that was freed on
656  * av_codec_close(). */
657  av_write_trailer(oc);
658 
659  /* Close each codec. */
660  if (have_video)
661  close_stream(oc, &video_st);
662  if (have_audio)
663  close_stream(oc, &audio_st);
664 
665  if (!(fmt->flags & AVFMT_NOFILE))
666  /* Close the output file. */
667  avio_closep(&oc->pb);
668 
669  /* free the stream */
671 
672  return 0;
673 }
int avio_open(AVIOContext **s, const char *url, int flags)
Create and initialize a AVIOContext for accessing the resource indicated by url.
Definition: aviobuf.c:979
int64_t next_pts
Definition: muxing.c:58
float, planar
Definition: samplefmt.h:69
#define NULL
Definition: coverity.c:32
const struct AVCodec * codec
Definition: avcodec.h:1651
enum AVCodecID codec_id
Definition: ffmpeg_vaapi.c:149
static enum AVPixelFormat pix_fmt
This structure describes decoded (raw) audio or video data.
Definition: frame.h:180
int main(int argc, char **argv)
Definition: muxing.c:557
AVCodec * avcodec_find_encoder(enum AVCodecID id)
Find a registered encoder with a matching codec ID.
Definition: utils.c:3037
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1044
const char * fmt
Definition: avisynth_c.h:632
int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd)
Rescale a 64-bit integer with specified rounding.
Definition: mathematics.c:58
int64_t bit_rate
the average bitrate
Definition: avcodec.h:1707
static int write_audio_frame(AVFormatContext *oc, OutputStream *ost)
Definition: muxing.c:309
AVStream * video_st
Definition: movenc-test.c:59
int max_b_frames
maximum number of B-frames between non-B-frames Note: The output will be delayed by max_b_frames+1 re...
Definition: avcodec.h:1928
enum AVCodecID video_codec
default video codec
Definition: avformat.h:533
static AVFormatContext * fmt_ctx
int index
stream index in AVFormatContext
Definition: avformat.h:877
float tincr
Definition: muxing.c:64
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:543
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1870
int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
Copy entries from one AVDictionary struct into another.
Definition: dict.c:216
static AVPacket pkt
int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Encode a frame of audio.
Definition: utils.c:1769
#define AV_CH_LAYOUT_STEREO
static void add_stream(OutputStream *ost, AVFormatContext *oc, AVCodec **codec, enum AVCodecID codec_id)
Definition: muxing.c:93
AVCodec.
Definition: avcodec.h:3535
static void open_video(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
Definition: muxing.c:396
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1779
static void close_stream(AVFormatContext *oc, OutputStream *ost)
Definition: muxing.c:545
int av_get_channel_layout_nb_channels(uint64_t channel_layout)
Return the number of channels in the channel layout.
Format I/O context.
Definition: avformat.h:1319
#define SCALE_FLAGS
Definition: muxing.c:50
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2411
int flags
can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS, AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH, AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
Definition: avformat.h:541
uint8_t
Round toward +infinity.
Definition: mathematics.h:74
av_cold struct SwrContext * swr_alloc(void)
Allocate SwrContext.
Definition: options.c:148
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:140
static void log_packet(const AVFormatContext *fmt_ctx, const AVPacket *pkt)
Definition: muxing.c:70
AVOptions.
timestamp utils, mostly useful for debugging/logging purposes
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1595
int id
Format-specific stream ID.
Definition: avformat.h:883
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:264
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4042
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1387
int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Encode a frame of video.
Definition: utils.c:1915
static AVFrame * frame
struct SwsContext * sws_getContext(int srcW, int srcH, enum AVPixelFormat srcFormat, int dstW, int dstH, enum AVPixelFormat dstFormat, int flags, SwsFilter *srcFilter, SwsFilter *dstFilter, const double *param)
Allocate and return an SwsContext.
Definition: utils.c:1848
struct SwrContext * swr_ctx
Definition: muxing.c:67
external API header
struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1338
int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
Definition: mux.c:148
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
void av_dump_format(AVFormatContext *ic, int index, const char *url, int is_output)
Print detailed information about the input or output format, such as duration, bitrate, streams, container, programs, metadata, side data, codec and time base.
Definition: dump.c:528
libswresample public header
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:189
int width
width and height of the video frame
Definition: frame.h:232
void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst)
Convert valid timing fields (timestamps / durations) in a packet from one timebase to another...
Definition: avpacket.c:610
static AVFrame * alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
Definition: muxing.c:373
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:153
#define av_ts2timestr(ts, tb)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: timestamp.h:76
The libswresample context.
int capabilities
Codec capabilities.
Definition: avcodec.h:3554
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:202
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1737
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:534
int samples_count
Definition: muxing.c:59
simple assert() macros that are a bit more flexible than ISO C assert().
AVFrame * frame
Definition: muxing.c:61
int64_t swr_get_delay(struct SwrContext *s, int64_t base)
Gets the delay the next input sample will experience relative to the next output sample.
Definition: swresample.c:848
#define AV_CODEC_CAP_VARIABLE_FRAME_SIZE
Audio encoder supports receiving a different number of samples in each call.
Definition: avcodec.h:1032
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2454
int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b)
Compare 2 timestamps each in its own timebases.
Definition: mathematics.c:147
uint64_t channel_layout
Channel layout of the audio data.
Definition: frame.h:345
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1375
audio channel layout utility functions
static AVFrame * alloc_audio_frame(enum AVSampleFormat sample_fmt, uint64_t channel_layout, int sample_rate, int nb_samples)
Definition: muxing.c:187
av_warn_unused_result int avformat_write_header(AVFormatContext *s, AVDictionary **options)
Allocate the stream private data and write the stream header to an output media file.
Definition: mux.c:476
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:149
int width
picture width / height.
Definition: avcodec.h:1829
#define width
#define AVFMT_GLOBALHEADER
Format wants global header.
Definition: avformat.h:483
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:119
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
Definition: utils.c:2268
static void fill_yuv_image(AVFrame *pict, int frame_index, int width, int height)
Definition: muxing.c:440
static int write_video_frame(AVFormatContext *oc, OutputStream *ost)
Definition: muxing.c:510
int mb_decision
macroblock decision mode
Definition: avcodec.h:2204
#define STREAM_PIX_FMT
Definition: muxing.c:48
preferred ID for MPEG-1/2 video decoding
Definition: avcodec.h:194
const char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
Definition: utils.c:3075
AVCodecContext * enc
Definition: muxing.c:55
Stream structure.
Definition: avformat.h:876
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:244
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:2423
sample_rate
#define STREAM_DURATION
Definition: muxing.c:46
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
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:164
enum AVCodecID codec_id
Definition: avcodec.h:1659
int sample_rate
samples per second
Definition: avcodec.h:2403
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:211
AVIOContext * pb
I/O context.
Definition: avformat.h:1361
main external API structure.
Definition: avcodec.h:1642
static AVFrame * get_video_frame(OutputStream *ost)
Definition: muxing.c:469
av_cold void swr_free(SwrContext **ss)
Free the given SwrContext and set the pointer to NULL.
Definition: swresample.c:140
int attribute_align_arg sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[], const int srcStride[], int srcSliceY, int srcSliceH, uint8_t *const dst[], const int dstStride[])
swscale wrapper, so we don't need to export the SwsContext.
Definition: swscale.c:751
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:69
int sample_rate
Sample rate of the audio data.
Definition: frame.h:340
rational number numerator/denominator
Definition: rational.h:43
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: utils.c:4070
#define STREAM_FRAME_RATE
Definition: muxing.c:47
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:1208
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: utils.c:3978
int attribute_align_arg swr_convert(struct SwrContext *s, uint8_t *out_arg[SWR_CH_MAX], int out_count, const uint8_t *in_arg[SWR_CH_MAX], int in_count)
Definition: swresample.c:695
int av_frame_get_buffer(AVFrame *frame, int align)
Allocate new buffer(s) for audio or video data.
Definition: frame.c:270
int av_frame_make_writable(AVFrame *frame)
Ensure that the frame data is writable, avoiding data copy if possible.
Definition: frame.c:531
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:194
#define AV_CODEC_FLAG_GLOBAL_HEADER
Place global headers in extradata instead of every keyframe.
Definition: avcodec.h:876
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:1855
Main libavformat public API header.
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:62
if(ret< 0)
Definition: vf_mcdeint.c:282
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:476
signed 16 bits
Definition: samplefmt.h:61
static double c[64]
AVStream * st
Definition: muxing.c:54
static void open_audio(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
Definition: muxing.c:215
float t
Definition: muxing.c:64
AVStream * audio_st
Definition: movenc-test.c:59
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:33
static int write_frame(AVFormatContext *fmt_ctx, const AVRational *time_base, AVStream *st, AVPacket *pkt)
Definition: muxing.c:81
#define av_ts2str(ts)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: timestamp.h:54
int channels
number of audio channels
Definition: avcodec.h:2404
enum AVCodecID audio_codec
default audio codec
Definition: avformat.h:532
AVFrame * tmp_frame
Definition: muxing.c:62
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1576
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1120
int height
Definition: frame.h:232
#define M_PI
Definition: mathematics.h:46
AVCodecParameters * codecpar
Definition: avformat.h:1006
#define height
int stream_index
Definition: avcodec.h:1579
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:913
int av_opt_set_sample_fmt(void *obj, const char *name, enum AVSampleFormat fmt, int search_flags)
Definition: opt.c:652
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
This structure stores compressed data.
Definition: avcodec.h:1554
void av_register_all(void)
Initialize libavformat and register all the muxers, demuxers and protocols.
Definition: allformats.c:44
int avio_closep(AVIOContext **s)
Close the resource accessed by the AVIOContext *s, free it and set the pointer pointing to it to NULL...
Definition: aviobuf.c:1038
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:237
float tincr2
Definition: muxing.c:64
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1570
for(j=16;j >0;--j)
struct SwsContext * sws_ctx
Definition: muxing.c:66
static AVFrame * get_audio_frame(OutputStream *ost)
Definition: muxing.c:280
av_cold int swr_init(struct SwrContext *s)
Initialize context after user parameters have been set.
Definition: swresample.c:155