FFmpeg 4.4.5
Loading...
Searching...
No Matches
muxing.c
Go to the documentation of this file.
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>
41#include <libavutil/timestamp.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
53typedef 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
66 struct SwsContext *sws_ctx;
69
70static void log_packet(const AVFormatContext *fmt_ctx, const AVPacket *pkt)
71{
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),
79}
80
83{
84 int ret;
85
86 // send the frame to the encoder
87 ret = avcodec_send_frame(c, frame);
88 if (ret < 0) {
89 fprintf(stderr, "Error sending a frame to the encoder: %s\n",
90 av_err2str(ret));
91 exit(1);
92 }
93
94 while (ret >= 0) {
95 AVPacket pkt = { 0 };
96
97 ret = avcodec_receive_packet(c, &pkt);
98 if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
99 break;
100 else if (ret < 0) {
101 fprintf(stderr, "Error encoding a frame: %s\n", av_err2str(ret));
102 exit(1);
103 }
104
105 /* rescale output packet timestamp values from codec to stream timebase */
107 pkt.stream_index = st->index;
108
109 /* Write the compressed frame to the media file. */
113 if (ret < 0) {
114 fprintf(stderr, "Error while writing output packet: %s\n", av_err2str(ret));
115 exit(1);
116 }
117 }
118
119 return ret == AVERROR_EOF ? 1 : 0;
120}
121
122/* Add an output stream. */
124 AVCodec **codec,
125 enum AVCodecID codec_id)
126{
128 int i;
129
130 /* find the encoder */
131 *codec = avcodec_find_encoder(codec_id);
132 if (!(*codec)) {
133 fprintf(stderr, "Could not find encoder for '%s'\n",
134 avcodec_get_name(codec_id));
135 exit(1);
136 }
137
138 ost->st = avformat_new_stream(oc, NULL);
139 if (!ost->st) {
140 fprintf(stderr, "Could not allocate stream\n");
141 exit(1);
142 }
143 ost->st->id = oc->nb_streams-1;
144 c = avcodec_alloc_context3(*codec);
145 if (!c) {
146 fprintf(stderr, "Could not alloc an encoding context\n");
147 exit(1);
148 }
149 ost->enc = c;
150
151 switch ((*codec)->type) {
153 c->sample_fmt = (*codec)->sample_fmts ?
154 (*codec)->sample_fmts[0] : AV_SAMPLE_FMT_FLTP;
155 c->bit_rate = 64000;
156 c->sample_rate = 44100;
157 if ((*codec)->supported_samplerates) {
158 c->sample_rate = (*codec)->supported_samplerates[0];
159 for (i = 0; (*codec)->supported_samplerates[i]; i++) {
160 if ((*codec)->supported_samplerates[i] == 44100)
161 c->sample_rate = 44100;
162 }
163 }
166 if ((*codec)->channel_layouts) {
167 c->channel_layout = (*codec)->channel_layouts[0];
168 for (i = 0; (*codec)->channel_layouts[i]; i++) {
169 if ((*codec)->channel_layouts[i] == AV_CH_LAYOUT_STEREO)
171 }
172 }
174 ost->st->time_base = (AVRational){ 1, c->sample_rate };
175 break;
176
178 c->codec_id = codec_id;
179
180 c->bit_rate = 400000;
181 /* Resolution must be a multiple of two. */
182 c->width = 352;
183 c->height = 288;
184 /* timebase: This is the fundamental unit of time (in seconds) in terms
185 * of which frame timestamps are represented. For fixed-fps content,
186 * timebase should be 1/framerate and timestamp increments should be
187 * identical to 1. */
189 c->time_base = ost->st->time_base;
190
191 c->gop_size = 12; /* emit one intra frame every twelve frames at most */
194 /* just for testing, we also add B-frames */
195 c->max_b_frames = 2;
196 }
198 /* Needed to avoid using macroblocks in which some coeffs overflow.
199 * This does not happen with normal video, it just happens here as
200 * the motion of the chroma plane does not match the luma plane. */
201 c->mb_decision = 2;
202 }
203 break;
204
205 default:
206 break;
207 }
208
209 /* Some formats want stream headers to be separate. */
212}
213
214/**************************************************************/
215/* audio output */
216
218 uint64_t channel_layout,
219 int sample_rate, int nb_samples)
220{
222 int ret;
223
224 if (!frame) {
225 fprintf(stderr, "Error allocating an audio frame\n");
226 exit(1);
227 }
228
229 frame->format = sample_fmt;
230 frame->channel_layout = channel_layout;
231 frame->sample_rate = sample_rate;
232 frame->nb_samples = nb_samples;
233
234 if (nb_samples) {
235 ret = av_frame_get_buffer(frame, 0);
236 if (ret < 0) {
237 fprintf(stderr, "Error allocating an audio buffer\n");
238 exit(1);
239 }
240 }
241
242 return frame;
243}
244
245static void open_audio(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
246{
248 int nb_samples;
249 int ret;
250 AVDictionary *opt = NULL;
251
252 c = ost->enc;
253
254 /* open it */
255 av_dict_copy(&opt, opt_arg, 0);
256 ret = avcodec_open2(c, codec, &opt);
257 av_dict_free(&opt);
258 if (ret < 0) {
259 fprintf(stderr, "Could not open audio codec: %s\n", av_err2str(ret));
260 exit(1);
261 }
262
263 /* init signal generator */
264 ost->t = 0;
265 ost->tincr = 2 * M_PI * 110.0 / c->sample_rate;
266 /* increment frequency by 110 Hz per second */
267 ost->tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate;
268
270 nb_samples = 10000;
271 else
272 nb_samples = c->frame_size;
273
275 c->sample_rate, nb_samples);
277 c->sample_rate, nb_samples);
278
279 /* copy the stream parameters to the muxer */
281 if (ret < 0) {
282 fprintf(stderr, "Could not copy the stream parameters\n");
283 exit(1);
284 }
285
286 /* create resampler context */
287 ost->swr_ctx = swr_alloc();
288 if (!ost->swr_ctx) {
289 fprintf(stderr, "Could not allocate resampler context\n");
290 exit(1);
291 }
292
293 /* set options */
294 av_opt_set_int (ost->swr_ctx, "in_channel_count", c->channels, 0);
295 av_opt_set_int (ost->swr_ctx, "in_sample_rate", c->sample_rate, 0);
296 av_opt_set_sample_fmt(ost->swr_ctx, "in_sample_fmt", AV_SAMPLE_FMT_S16, 0);
297 av_opt_set_int (ost->swr_ctx, "out_channel_count", c->channels, 0);
298 av_opt_set_int (ost->swr_ctx, "out_sample_rate", c->sample_rate, 0);
299 av_opt_set_sample_fmt(ost->swr_ctx, "out_sample_fmt", c->sample_fmt, 0);
300
301 /* initialize the resampling context */
302 if ((ret = swr_init(ost->swr_ctx)) < 0) {
303 fprintf(stderr, "Failed to initialize the resampling context\n");
304 exit(1);
305 }
306}
307
308/* Prepare a 16 bit dummy audio frame of 'frame_size' samples and
309 * 'nb_channels' channels. */
311{
312 AVFrame *frame = ost->tmp_frame;
313 int j, i, v;
314 int16_t *q = (int16_t*)frame->data[0];
315
316 /* check if we want to generate more frames */
317 if (av_compare_ts(ost->next_pts, ost->enc->time_base,
318 STREAM_DURATION, (AVRational){ 1, 1 }) > 0)
319 return NULL;
320
321 for (j = 0; j <frame->nb_samples; j++) {
322 v = (int)(sin(ost->t) * 10000);
323 for (i = 0; i < ost->enc->channels; i++)
324 *q++ = v;
325 ost->t += ost->tincr;
326 ost->tincr += ost->tincr2;
327 }
328
329 frame->pts = ost->next_pts;
330 ost->next_pts += frame->nb_samples;
331
332 return frame;
333}
334
335/*
336 * encode one audio frame and send it to the muxer
337 * return 1 when encoding is finished, 0 otherwise
338 */
340{
342 AVFrame *frame;
343 int ret;
344 int dst_nb_samples;
345
346 c = ost->enc;
347
348 frame = get_audio_frame(ost);
349
350 if (frame) {
351 /* convert samples from native format to destination codec format, using the resampler */
352 /* compute destination number of samples */
353 dst_nb_samples = swr_get_delay(ost->swr_ctx, c->sample_rate) + frame->nb_samples;
354 av_assert0(dst_nb_samples == frame->nb_samples);
355
356 /* when we pass a frame to the encoder, it may keep a reference to it
357 * internally;
358 * make sure we do not overwrite it here
359 */
360 ret = av_frame_make_writable(ost->frame);
361 if (ret < 0)
362 exit(1);
363
364 /* convert to destination format */
365 ret = swr_convert(ost->swr_ctx,
366 ost->frame->data, dst_nb_samples,
367 (const uint8_t **)frame->data, frame->nb_samples);
368 if (ret < 0) {
369 fprintf(stderr, "Error while converting\n");
370 exit(1);
371 }
372 frame = ost->frame;
373
374 frame->pts = av_rescale_q(ost->samples_count, (AVRational){1, c->sample_rate}, c->time_base);
375 ost->samples_count += dst_nb_samples;
376 }
377
378 return write_frame(oc, c, ost->st, frame);
379}
380
381/**************************************************************/
382/* video output */
383
385{
386 AVFrame *picture;
387 int ret;
388
389 picture = av_frame_alloc();
390 if (!picture)
391 return NULL;
392
393 picture->format = pix_fmt;
394 picture->width = width;
395 picture->height = height;
396
397 /* allocate the buffers for the frame data */
398 ret = av_frame_get_buffer(picture, 0);
399 if (ret < 0) {
400 fprintf(stderr, "Could not allocate frame data.\n");
401 exit(1);
402 }
403
404 return picture;
405}
406
407static void open_video(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
408{
409 int ret;
410 AVCodecContext *c = ost->enc;
411 AVDictionary *opt = NULL;
412
413 av_dict_copy(&opt, opt_arg, 0);
414
415 /* open the codec */
416 ret = avcodec_open2(c, codec, &opt);
417 av_dict_free(&opt);
418 if (ret < 0) {
419 fprintf(stderr, "Could not open video codec: %s\n", av_err2str(ret));
420 exit(1);
421 }
422
423 /* allocate and init a re-usable frame */
424 ost->frame = alloc_picture(c->pix_fmt, c->width, c->height);
425 if (!ost->frame) {
426 fprintf(stderr, "Could not allocate video frame\n");
427 exit(1);
428 }
429
430 /* If the output format is not YUV420P, then a temporary YUV420P
431 * picture is needed too. It is then converted to the required
432 * output format. */
433 ost->tmp_frame = NULL;
434 if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
436 if (!ost->tmp_frame) {
437 fprintf(stderr, "Could not allocate temporary picture\n");
438 exit(1);
439 }
440 }
441
442 /* copy the stream parameters to the muxer */
444 if (ret < 0) {
445 fprintf(stderr, "Could not copy the stream parameters\n");
446 exit(1);
447 }
448}
449
450/* Prepare a dummy image. */
451static void fill_yuv_image(AVFrame *pict, int frame_index,
452 int width, int height)
453{
454 int x, y, i;
455
456 i = frame_index;
457
458 /* Y */
459 for (y = 0; y < height; y++)
460 for (x = 0; x < width; x++)
461 pict->data[0][y * pict->linesize[0] + x] = x + y + i * 3;
462
463 /* Cb and Cr */
464 for (y = 0; y < height / 2; y++) {
465 for (x = 0; x < width / 2; x++) {
466 pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
467 pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
468 }
469 }
470}
471
473{
474 AVCodecContext *c = ost->enc;
475
476 /* check if we want to generate more frames */
477 if (av_compare_ts(ost->next_pts, c->time_base,
478 STREAM_DURATION, (AVRational){ 1, 1 }) > 0)
479 return NULL;
480
481 /* when we pass a frame to the encoder, it may keep a reference to it
482 * internally; make sure we do not overwrite it here */
483 if (av_frame_make_writable(ost->frame) < 0)
484 exit(1);
485
486 if (c->pix_fmt != AV_PIX_FMT_YUV420P) {
487 /* as we only generate a YUV420P picture, we must convert it
488 * to the codec pixel format if needed */
489 if (!ost->sws_ctx) {
490 ost->sws_ctx = sws_getContext(c->width, c->height,
492 c->width, c->height,
493 c->pix_fmt,
494 SCALE_FLAGS, NULL, NULL, NULL);
495 if (!ost->sws_ctx) {
496 fprintf(stderr,
497 "Could not initialize the conversion context\n");
498 exit(1);
499 }
500 }
501 fill_yuv_image(ost->tmp_frame, ost->next_pts, c->width, c->height);
502 sws_scale(ost->sws_ctx, (const uint8_t * const *) ost->tmp_frame->data,
503 ost->tmp_frame->linesize, 0, c->height, ost->frame->data,
504 ost->frame->linesize);
505 } else {
506 fill_yuv_image(ost->frame, ost->next_pts, c->width, c->height);
507 }
508
509 ost->frame->pts = ost->next_pts++;
510
511 return ost->frame;
512}
513
514/*
515 * encode one video frame and send it to the muxer
516 * return 1 when encoding is finished, 0 otherwise
517 */
519{
520 return write_frame(oc, ost->enc, ost->st, get_video_frame(ost));
521}
522
524{
526 av_frame_free(&ost->frame);
529 swr_free(&ost->swr_ctx);
530}
531
532/**************************************************************/
533/* media file output */
534
535int main(int argc, char **argv)
536{
537 OutputStream video_st = { 0 }, audio_st = { 0 };
538 const char *filename;
539 AVOutputFormat *fmt;
540 AVFormatContext *oc;
541 AVCodec *audio_codec, *video_codec;
542 int ret;
543 int have_video = 0, have_audio = 0;
544 int encode_video = 0, encode_audio = 0;
545 AVDictionary *opt = NULL;
546 int i;
547
548 if (argc < 2) {
549 printf("usage: %s output_file\n"
550 "API example program to output a media file with libavformat.\n"
551 "This program generates a synthetic audio and video stream, encodes and\n"
552 "muxes them into a file named output_file.\n"
553 "The output format is automatically guessed according to the file extension.\n"
554 "Raw images can also be output by using '%%d' in the filename.\n"
555 "\n", argv[0]);
556 return 1;
557 }
558
559 filename = argv[1];
560 for (i = 2; i+1 < argc; i+=2) {
561 if (!strcmp(argv[i], "-flags") || !strcmp(argv[i], "-fflags"))
562 av_dict_set(&opt, argv[i]+1, argv[i+1], 0);
563 }
564
565 /* allocate the output media context */
566 avformat_alloc_output_context2(&oc, NULL, NULL, filename);
567 if (!oc) {
568 printf("Could not deduce output format from file extension: using MPEG.\n");
569 avformat_alloc_output_context2(&oc, NULL, "mpeg", filename);
570 }
571 if (!oc)
572 return 1;
573
574 fmt = oc->oformat;
575
576 /* Add the audio and video streams using the default format codecs
577 * and initialize the codecs. */
578 if (fmt->video_codec != AV_CODEC_ID_NONE) {
579 add_stream(&video_st, oc, &video_codec, fmt->video_codec);
580 have_video = 1;
581 encode_video = 1;
582 }
583 if (fmt->audio_codec != AV_CODEC_ID_NONE) {
584 add_stream(&audio_st, oc, &audio_codec, fmt->audio_codec);
585 have_audio = 1;
586 encode_audio = 1;
587 }
588
589 /* Now that all the parameters are set, we can open the audio and
590 * video codecs and allocate the necessary encode buffers. */
591 if (have_video)
592 open_video(oc, video_codec, &video_st, opt);
593
594 if (have_audio)
595 open_audio(oc, audio_codec, &audio_st, opt);
596
597 av_dump_format(oc, 0, filename, 1);
598
599 /* open the output file, if needed */
600 if (!(fmt->flags & AVFMT_NOFILE)) {
601 ret = avio_open(&oc->pb, filename, AVIO_FLAG_WRITE);
602 if (ret < 0) {
603 fprintf(stderr, "Could not open '%s': %s\n", filename,
604 av_err2str(ret));
605 return 1;
606 }
607 }
608
609 /* Write the stream header, if any. */
610 ret = avformat_write_header(oc, &opt);
611 if (ret < 0) {
612 fprintf(stderr, "Error occurred when opening output file: %s\n",
613 av_err2str(ret));
614 return 1;
615 }
616
617 while (encode_video || encode_audio) {
618 /* select the stream to encode */
619 if (encode_video &&
620 (!encode_audio || av_compare_ts(video_st.next_pts, video_st.enc->time_base,
621 audio_st.next_pts, audio_st.enc->time_base) <= 0)) {
622 encode_video = !write_video_frame(oc, &video_st);
623 } else {
624 encode_audio = !write_audio_frame(oc, &audio_st);
625 }
626 }
627
628 /* Write the trailer, if any. The trailer must be written before you
629 * close the CodecContexts open when you wrote the header; otherwise
630 * av_write_trailer() may try to use memory that was freed on
631 * av_codec_close(). */
633
634 /* Close each codec. */
635 if (have_video)
636 close_stream(oc, &video_st);
637 if (have_audio)
638 close_stream(oc, &audio_st);
639
640 if (!(fmt->flags & AVFMT_NOFILE))
641 /* Close the output file. */
642 avio_closep(&oc->pb);
643
644 /* free the stream */
646
647 return 0;
648}
simple assert() macros that are a bit more flexible than ISO C assert().
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition avassert.h:37
Main libavformat public API header.
int avformat_alloc_output_context2(AVFormatContext **ctx, ff_const59 AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition avformat.h:458
#define AVFMT_GLOBALHEADER
Format wants global header.
Definition avformat.h:461
int avio_open(AVIOContext **s, const char *url, int flags)
Create and initialize a AVIOContext for accessing the resource indicated by url.
#define AVIO_FLAG_WRITE
write-only
Definition avio.h:675
int avio_closep(AVIOContext **s)
Close the resource accessed by the AVIOContext *s, free it and set the pointer pointing to it to NULL...
int main(int argc, char *argv[])
audio channel layout utility functions
static int width
static AVPacket * pkt
static AVFormatContext * fmt_ctx
static enum AVPixelFormat pix_fmt
static int height
static AVFrame * frame
#define AV_CH_LAYOUT_STEREO
int av_get_channel_layout_nb_channels(uint64_t channel_layout)
Return the number of channels in the channel layout.
int avcodec_parameters_from_context(AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
#define AV_CODEC_CAP_VARIABLE_FRAME_SIZE
Audio encoder supports receiving a different number of samples in each call.
Definition codec.h:129
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
#define AV_CODEC_FLAG_GLOBAL_HEADER
Place global headers in extradata instead of every keyframe.
Definition avcodec.h:329
const char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition codec_id.h:46
AVCodec * avcodec_find_encoder(enum AVCodecID id)
Find a registered encoder with a matching codec ID.
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
@ AV_CODEC_ID_NONE
Definition codec_id.h:47
@ AV_CODEC_ID_MPEG1VIDEO
Definition codec_id.h:50
@ AV_CODEC_ID_MPEG2VIDEO
preferred ID for MPEG-1/2 video decoding
Definition codec_id.h:51
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
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.
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
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.
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
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,...
void av_dict_free(AVDictionary **m)
Free all the memory allocated for an AVDictionary struct and all keys and values.
struct AVDictionary AVDictionary
Definition dict.h:86
int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
Copy entries from one AVDictionary struct into another.
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
#define AVERROR_EOF
End of file.
Definition error.h:55
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition error.h:119
#define AVERROR(e)
Definition error.h:43
int av_frame_get_buffer(AVFrame *frame, int align)
Allocate new buffer(s) for audio or video data.
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
int av_frame_make_writable(AVFrame *frame)
Ensure that the frame data is writable, avoiding data copy if possible.
int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b)
Compare two timestamps each in its own time base.
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const
Rescale a 64-bit integer by 2 rational numbers.
@ AVMEDIA_TYPE_AUDIO
Definition avutil.h:202
@ AVMEDIA_TYPE_VIDEO
Definition avutil.h:201
AVSampleFormat
Audio sample formats.
Definition samplefmt.h:58
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition samplefmt.h:69
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition samplefmt.h:61
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.
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
int sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[], const int srcStride[], int srcSliceY, int srcSliceH, uint8_t *const dst[], const int dstStride[])
Scale the image slice in srcSlice and put the resulting scaled slice in the image in dst.
struct SwrContext * swr_alloc(void)
Allocate SwrContext.
struct SwrContext SwrContext
The libswresample context.
Definition swresample.h:182
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.
void swr_free(struct SwrContext **s)
Free the given SwrContext and set the pointer to NULL.
int swr_convert(struct SwrContext *s, uint8_t **out, int out_count, const uint8_t **in, int in_count)
Convert audio.
int swr_init(struct SwrContext *s)
Initialize context after user parameters have been set.
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
int av_opt_set_sample_fmt(void *obj, const char *name, enum AVSampleFormat fmt, int search_flags)
#define M_PI
Definition mathematics.h:52
static int write_frame(AVFormatContext *fmt_ctx, AVCodecContext *c, AVStream *st, AVFrame *frame)
Definition muxing.c:81
static AVFrame * alloc_audio_frame(enum AVSampleFormat sample_fmt, uint64_t channel_layout, int sample_rate, int nb_samples)
Definition muxing.c:217
static AVFrame * get_video_frame(OutputStream *ost)
Definition muxing.c:472
static void open_video(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
Definition muxing.c:407
static int write_video_frame(AVFormatContext *oc, OutputStream *ost)
Definition muxing.c:518
static int write_audio_frame(AVFormatContext *oc, OutputStream *ost)
Definition muxing.c:339
static AVFrame * alloc_picture(enum AVPixelFormat pix_fmt, int width, int height)
Definition muxing.c:384
static void close_stream(AVFormatContext *oc, OutputStream *ost)
Definition muxing.c:523
static AVFrame * get_audio_frame(OutputStream *ost)
Definition muxing.c:310
#define SCALE_FLAGS
Definition muxing.c:50
static void log_packet(const AVFormatContext *fmt_ctx, const AVPacket *pkt)
Definition muxing.c:70
static void fill_yuv_image(AVFrame *pict, int frame_index, int width, int height)
Definition muxing.c:451
#define STREAM_DURATION
Definition muxing.c:46
#define STREAM_FRAME_RATE
Definition muxing.c:47
#define STREAM_PIX_FMT
Definition muxing.c:48
static void open_audio(AVFormatContext *oc, AVCodec *codec, OutputStream *ost, AVDictionary *opt_arg)
Definition muxing.c:245
static void add_stream(OutputStream *ost, AVFormatContext *oc, AVCodec **codec, enum AVCodecID codec_id)
Definition muxing.c:123
AVOptions.
AVPixelFormat
Pixel format.
Definition pixfmt.h:64
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition pixfmt.h:66
main external API structure.
Definition avcodec.h:536
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition avcodec.h:746
int width
picture width / height.
Definition avcodec.h:709
enum AVSampleFormat sample_fmt
audio sample format
Definition avcodec.h:1204
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:796
int mb_decision
macroblock decision mode
Definition avcodec.h:1024
int64_t bit_rate
the average bitrate
Definition avcodec.h:586
const struct AVCodec * codec
Definition avcodec.h:545
int sample_rate
samples per second
Definition avcodec.h:1196
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition avcodec.h:731
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition avcodec.h:659
int flags
AV_CODEC_FLAG_*.
Definition avcodec.h:616
int channels
number of audio channels
Definition avcodec.h:1197
enum AVCodecID codec_id
Definition avcodec.h:546
uint64_t channel_layout
Audio channel layout.
Definition avcodec.h:1247
int frame_size
Number of samples per channel in an audio frame.
Definition avcodec.h:1216
AVCodec.
Definition codec.h:197
int capabilities
Codec capabilities.
Definition codec.h:216
Format I/O context.
Definition avformat.h:1232
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition avformat.h:1288
AVIOContext * pb
I/O context.
Definition avformat.h:1274
ff_const59 struct AVOutputFormat * oformat
The output container format.
Definition avformat.h:1251
AVStream ** streams
A list of all streams in the file.
Definition avformat.h:1300
This structure describes decoded (raw) audio or video data.
Definition frame.h:318
int nb_samples
number of audio samples (per channel) described by this frame
Definition frame.h:384
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition frame.h:411
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition frame.h:332
int width
Definition frame.h:376
int height
Definition frame.h:376
uint64_t channel_layout
Channel layout of the audio data.
Definition frame.h:495
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition frame.h:349
int sample_rate
Sample rate of the audio data.
Definition frame.h:490
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames,...
Definition frame.h:391
enum AVCodecID video_codec
default video codec
Definition avformat.h:502
enum AVCodecID audio_codec
default audio codec
Definition avformat.h:501
int flags
can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS,...
Definition avformat.h:510
This structure stores compressed data.
Definition packet.h:346
int stream_index
Definition packet.h:371
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition packet.h:387
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition packet.h:362
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition packet.h:368
Rational number (pair of numerator and denominator).
Definition rational.h:58
Stream structure.
Definition avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition avformat.h:1038
int id
Format-specific stream ID.
Definition avformat.h:880
int index
stream index in AVFormatContext
Definition avformat.h:874
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition avformat.h:902
float tincr2
Definition muxing.c:64
AVFrame * frame
Definition muxing.c:61
int samples_count
Definition muxing.c:59
struct SwrContext * swr_ctx
Definition muxing.c:67
AVFrame * tmp_frame
Definition muxing.c:62
struct SwsContext * sws_ctx
Definition muxing.c:66
int64_t next_pts
Definition muxing.c:58
float t
Definition muxing.c:64
AVStream * st
Definition muxing.c:54
AVCodecContext * enc
Definition muxing.c:55
float tincr
Definition muxing.c:64
libswresample public header
external API header
timestamp utils, mostly useful for debugging/logging purposes
#define av_ts2str(ts)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition timestamp.h:54
#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