FFmpeg
transcode.c
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1 /*
2  * Copyright (c) 2010 Nicolas George
3  * Copyright (c) 2011 Stefano Sabatini
4  * Copyright (c) 2014 Andrey Utkin
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 /**
26  * @file demuxing, decoding, filtering, encoding and muxing API usage example
27  * @example transcode.c
28  *
29  * Convert input to output file, applying some hard-coded filter-graph on both
30  * audio and video streams.
31  */
32 
33 #include <libavcodec/avcodec.h>
34 #include <libavformat/avformat.h>
35 #include <libavfilter/buffersink.h>
36 #include <libavfilter/buffersrc.h>
38 #include <libavutil/mem.h>
39 #include <libavutil/opt.h>
40 #include <libavutil/pixdesc.h>
41 
44 typedef struct FilteringContext {
48 
53 
54 typedef struct StreamContext {
57 
61 
62 static int open_input_file(const char *filename)
63 {
64  int ret;
65  unsigned int i;
66 
67  ifmt_ctx = NULL;
68  if ((ret = avformat_open_input(&ifmt_ctx, filename, NULL, NULL)) < 0) {
69  av_log(NULL, AV_LOG_ERROR, "Cannot open input file\n");
70  return ret;
71  }
72 
74  av_log(NULL, AV_LOG_ERROR, "Cannot find stream information\n");
75  return ret;
76  }
77 
79  if (!stream_ctx)
80  return AVERROR(ENOMEM);
81 
82  for (i = 0; i < ifmt_ctx->nb_streams; i++) {
83  AVStream *stream = ifmt_ctx->streams[i];
84  const AVCodec *dec = avcodec_find_decoder(stream->codecpar->codec_id);
85  AVCodecContext *codec_ctx;
86  if (!dec) {
87  av_log(NULL, AV_LOG_ERROR, "Failed to find decoder for stream #%u\n", i);
89  }
90  codec_ctx = avcodec_alloc_context3(dec);
91  if (!codec_ctx) {
92  av_log(NULL, AV_LOG_ERROR, "Failed to allocate the decoder context for stream #%u\n", i);
93  return AVERROR(ENOMEM);
94  }
95  ret = avcodec_parameters_to_context(codec_ctx, stream->codecpar);
96  if (ret < 0) {
97  av_log(NULL, AV_LOG_ERROR, "Failed to copy decoder parameters to input decoder context "
98  "for stream #%u\n", i);
99  return ret;
100  }
101 
102  /* Inform the decoder about the timebase for the packet timestamps.
103  * This is highly recommended, but not mandatory. */
104  codec_ctx->pkt_timebase = stream->time_base;
105 
106  /* Reencode video & audio and remux subtitles etc. */
107  if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO
108  || codec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) {
109  if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO)
110  codec_ctx->framerate = av_guess_frame_rate(ifmt_ctx, stream, NULL);
111  /* Open decoder */
112  ret = avcodec_open2(codec_ctx, dec, NULL);
113  if (ret < 0) {
114  av_log(NULL, AV_LOG_ERROR, "Failed to open decoder for stream #%u\n", i);
115  return ret;
116  }
117  }
118  stream_ctx[i].dec_ctx = codec_ctx;
119 
121  if (!stream_ctx[i].dec_frame)
122  return AVERROR(ENOMEM);
123  }
124 
125  av_dump_format(ifmt_ctx, 0, filename, 0);
126  return 0;
127 }
128 
129 static int open_output_file(const char *filename)
130 {
131  AVStream *out_stream;
132  AVStream *in_stream;
133  AVCodecContext *dec_ctx, *enc_ctx;
134  const AVCodec *encoder;
135  int ret;
136  unsigned int i;
137 
138  ofmt_ctx = NULL;
140  if (!ofmt_ctx) {
141  av_log(NULL, AV_LOG_ERROR, "Could not create output context\n");
142  return AVERROR_UNKNOWN;
143  }
144 
145 
146  for (i = 0; i < ifmt_ctx->nb_streams; i++) {
147  out_stream = avformat_new_stream(ofmt_ctx, NULL);
148  if (!out_stream) {
149  av_log(NULL, AV_LOG_ERROR, "Failed allocating output stream\n");
150  return AVERROR_UNKNOWN;
151  }
152 
153  in_stream = ifmt_ctx->streams[i];
155 
158  /* in this example, we choose transcoding to same codec */
160  if (!encoder) {
161  av_log(NULL, AV_LOG_FATAL, "Necessary encoder not found\n");
162  return AVERROR_INVALIDDATA;
163  }
164  enc_ctx = avcodec_alloc_context3(encoder);
165  if (!enc_ctx) {
166  av_log(NULL, AV_LOG_FATAL, "Failed to allocate the encoder context\n");
167  return AVERROR(ENOMEM);
168  }
169 
170  /* In this example, we transcode to same properties (picture size,
171  * sample rate etc.). These properties can be changed for output
172  * streams easily using filters */
174  enc_ctx->height = dec_ctx->height;
175  enc_ctx->width = dec_ctx->width;
177  /* take first format from list of supported formats */
178  if (encoder->pix_fmts)
179  enc_ctx->pix_fmt = encoder->pix_fmts[0];
180  else
181  enc_ctx->pix_fmt = dec_ctx->pix_fmt;
182  /* video time_base can be set to whatever is handy and supported by encoder */
183  enc_ctx->time_base = av_inv_q(dec_ctx->framerate);
184  } else {
185  enc_ctx->sample_rate = dec_ctx->sample_rate;
187  if (ret < 0)
188  return ret;
189  /* take first format from list of supported formats */
190  enc_ctx->sample_fmt = encoder->sample_fmts[0];
191  enc_ctx->time_base = (AVRational){1, enc_ctx->sample_rate};
192  }
193 
196 
197  /* Third parameter can be used to pass settings to encoder */
198  ret = avcodec_open2(enc_ctx, encoder, NULL);
199  if (ret < 0) {
200  av_log(NULL, AV_LOG_ERROR, "Cannot open %s encoder for stream #%u\n", encoder->name, i);
201  return ret;
202  }
203  ret = avcodec_parameters_from_context(out_stream->codecpar, enc_ctx);
204  if (ret < 0) {
205  av_log(NULL, AV_LOG_ERROR, "Failed to copy encoder parameters to output stream #%u\n", i);
206  return ret;
207  }
208 
209  out_stream->time_base = enc_ctx->time_base;
210  stream_ctx[i].enc_ctx = enc_ctx;
211  } else if (dec_ctx->codec_type == AVMEDIA_TYPE_UNKNOWN) {
212  av_log(NULL, AV_LOG_FATAL, "Elementary stream #%d is of unknown type, cannot proceed\n", i);
213  return AVERROR_INVALIDDATA;
214  } else {
215  /* if this stream must be remuxed */
216  ret = avcodec_parameters_copy(out_stream->codecpar, in_stream->codecpar);
217  if (ret < 0) {
218  av_log(NULL, AV_LOG_ERROR, "Copying parameters for stream #%u failed\n", i);
219  return ret;
220  }
221  out_stream->time_base = in_stream->time_base;
222  }
223 
224  }
225  av_dump_format(ofmt_ctx, 0, filename, 1);
226 
227  if (!(ofmt_ctx->oformat->flags & AVFMT_NOFILE)) {
228  ret = avio_open(&ofmt_ctx->pb, filename, AVIO_FLAG_WRITE);
229  if (ret < 0) {
230  av_log(NULL, AV_LOG_ERROR, "Could not open output file '%s'", filename);
231  return ret;
232  }
233  }
234 
235  /* init muxer, write output file header */
237  if (ret < 0) {
238  av_log(NULL, AV_LOG_ERROR, "Error occurred when opening output file\n");
239  return ret;
240  }
241 
242  return 0;
243 }
244 
246  AVCodecContext *enc_ctx, const char *filter_spec)
247 {
248  char args[512];
249  int ret = 0;
250  const AVFilter *buffersrc = NULL;
251  const AVFilter *buffersink = NULL;
257 
258  if (!outputs || !inputs || !filter_graph) {
259  ret = AVERROR(ENOMEM);
260  goto end;
261  }
262 
264  buffersrc = avfilter_get_by_name("buffer");
265  buffersink = avfilter_get_by_name("buffersink");
266  if (!buffersrc || !buffersink) {
267  av_log(NULL, AV_LOG_ERROR, "filtering source or sink element not found\n");
269  goto end;
270  }
271 
272  snprintf(args, sizeof(args),
273  "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
278 
279  ret = avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in",
280  args, NULL, filter_graph);
281  if (ret < 0) {
282  av_log(NULL, AV_LOG_ERROR, "Cannot create buffer source\n");
283  goto end;
284  }
285 
286  ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out",
288  if (ret < 0) {
289  av_log(NULL, AV_LOG_ERROR, "Cannot create buffer sink\n");
290  goto end;
291  }
292 
293  ret = av_opt_set_bin(buffersink_ctx, "pix_fmts",
294  (uint8_t*)&enc_ctx->pix_fmt, sizeof(enc_ctx->pix_fmt),
296  if (ret < 0) {
297  av_log(NULL, AV_LOG_ERROR, "Cannot set output pixel format\n");
298  goto end;
299  }
300  } else if (dec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) {
301  char buf[64];
302  buffersrc = avfilter_get_by_name("abuffer");
303  buffersink = avfilter_get_by_name("abuffersink");
304  if (!buffersrc || !buffersink) {
305  av_log(NULL, AV_LOG_ERROR, "filtering source or sink element not found\n");
307  goto end;
308  }
309 
312  av_channel_layout_describe(&dec_ctx->ch_layout, buf, sizeof(buf));
313  snprintf(args, sizeof(args),
314  "time_base=%d/%d:sample_rate=%d:sample_fmt=%s:channel_layout=%s",
317  buf);
318  ret = avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in",
319  args, NULL, filter_graph);
320  if (ret < 0) {
321  av_log(NULL, AV_LOG_ERROR, "Cannot create audio buffer source\n");
322  goto end;
323  }
324 
325  ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out",
327  if (ret < 0) {
328  av_log(NULL, AV_LOG_ERROR, "Cannot create audio buffer sink\n");
329  goto end;
330  }
331 
332  ret = av_opt_set_bin(buffersink_ctx, "sample_fmts",
333  (uint8_t*)&enc_ctx->sample_fmt, sizeof(enc_ctx->sample_fmt),
335  if (ret < 0) {
336  av_log(NULL, AV_LOG_ERROR, "Cannot set output sample format\n");
337  goto end;
338  }
339 
340  av_channel_layout_describe(&enc_ctx->ch_layout, buf, sizeof(buf));
341  ret = av_opt_set(buffersink_ctx, "ch_layouts",
343  if (ret < 0) {
344  av_log(NULL, AV_LOG_ERROR, "Cannot set output channel layout\n");
345  goto end;
346  }
347 
348  ret = av_opt_set_bin(buffersink_ctx, "sample_rates",
349  (uint8_t*)&enc_ctx->sample_rate, sizeof(enc_ctx->sample_rate),
351  if (ret < 0) {
352  av_log(NULL, AV_LOG_ERROR, "Cannot set output sample rate\n");
353  goto end;
354  }
355  } else {
357  goto end;
358  }
359 
360  /* Endpoints for the filter graph. */
361  outputs->name = av_strdup("in");
362  outputs->filter_ctx = buffersrc_ctx;
363  outputs->pad_idx = 0;
364  outputs->next = NULL;
365 
366  inputs->name = av_strdup("out");
367  inputs->filter_ctx = buffersink_ctx;
368  inputs->pad_idx = 0;
369  inputs->next = NULL;
370 
371  if (!outputs->name || !inputs->name) {
372  ret = AVERROR(ENOMEM);
373  goto end;
374  }
375 
376  if ((ret = avfilter_graph_parse_ptr(filter_graph, filter_spec,
377  &inputs, &outputs, NULL)) < 0)
378  goto end;
379 
381  goto end;
382 
383  /* Fill FilteringContext */
386  fctx->filter_graph = filter_graph;
387 
388 end:
391 
392  return ret;
393 }
394 
395 static int init_filters(void)
396 {
397  const char *filter_spec;
398  unsigned int i;
399  int ret;
401  if (!filter_ctx)
402  return AVERROR(ENOMEM);
403 
404  for (i = 0; i < ifmt_ctx->nb_streams; i++) {
410  continue;
411 
412 
414  filter_spec = "null"; /* passthrough (dummy) filter for video */
415  else
416  filter_spec = "anull"; /* passthrough (dummy) filter for audio */
418  stream_ctx[i].enc_ctx, filter_spec);
419  if (ret)
420  return ret;
421 
423  if (!filter_ctx[i].enc_pkt)
424  return AVERROR(ENOMEM);
425 
427  if (!filter_ctx[i].filtered_frame)
428  return AVERROR(ENOMEM);
429  }
430  return 0;
431 }
432 
433 static int encode_write_frame(unsigned int stream_index, int flush)
434 {
435  StreamContext *stream = &stream_ctx[stream_index];
436  FilteringContext *filter = &filter_ctx[stream_index];
437  AVFrame *filt_frame = flush ? NULL : filter->filtered_frame;
438  AVPacket *enc_pkt = filter->enc_pkt;
439  int ret;
440 
441  av_log(NULL, AV_LOG_INFO, "Encoding frame\n");
442  /* encode filtered frame */
443  av_packet_unref(enc_pkt);
444 
445  if (filt_frame && filt_frame->pts != AV_NOPTS_VALUE)
446  filt_frame->pts = av_rescale_q(filt_frame->pts, filt_frame->time_base,
447  stream->enc_ctx->time_base);
448 
449  ret = avcodec_send_frame(stream->enc_ctx, filt_frame);
450 
451  if (ret < 0)
452  return ret;
453 
454  while (ret >= 0) {
455  ret = avcodec_receive_packet(stream->enc_ctx, enc_pkt);
456 
457  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
458  return 0;
459 
460  /* prepare packet for muxing */
461  enc_pkt->stream_index = stream_index;
462  av_packet_rescale_ts(enc_pkt,
463  stream->enc_ctx->time_base,
464  ofmt_ctx->streams[stream_index]->time_base);
465 
466  av_log(NULL, AV_LOG_DEBUG, "Muxing frame\n");
467  /* mux encoded frame */
469  }
470 
471  return ret;
472 }
473 
474 static int filter_encode_write_frame(AVFrame *frame, unsigned int stream_index)
475 {
476  FilteringContext *filter = &filter_ctx[stream_index];
477  int ret;
478 
479  av_log(NULL, AV_LOG_INFO, "Pushing decoded frame to filters\n");
480  /* push the decoded frame into the filtergraph */
481  ret = av_buffersrc_add_frame_flags(filter->buffersrc_ctx,
482  frame, 0);
483  if (ret < 0) {
484  av_log(NULL, AV_LOG_ERROR, "Error while feeding the filtergraph\n");
485  return ret;
486  }
487 
488  /* pull filtered frames from the filtergraph */
489  while (1) {
490  av_log(NULL, AV_LOG_INFO, "Pulling filtered frame from filters\n");
491  ret = av_buffersink_get_frame(filter->buffersink_ctx,
492  filter->filtered_frame);
493  if (ret < 0) {
494  /* if no more frames for output - returns AVERROR(EAGAIN)
495  * if flushed and no more frames for output - returns AVERROR_EOF
496  * rewrite retcode to 0 to show it as normal procedure completion
497  */
498  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
499  ret = 0;
500  break;
501  }
502 
503  filter->filtered_frame->time_base = av_buffersink_get_time_base(filter->buffersink_ctx);;
504  filter->filtered_frame->pict_type = AV_PICTURE_TYPE_NONE;
505  ret = encode_write_frame(stream_index, 0);
506  av_frame_unref(filter->filtered_frame);
507  if (ret < 0)
508  break;
509  }
510 
511  return ret;
512 }
513 
514 static int flush_encoder(unsigned int stream_index)
515 {
516  if (!(stream_ctx[stream_index].enc_ctx->codec->capabilities &
518  return 0;
519 
520  av_log(NULL, AV_LOG_INFO, "Flushing stream #%u encoder\n", stream_index);
521  return encode_write_frame(stream_index, 1);
522 }
523 
524 int main(int argc, char **argv)
525 {
526  int ret;
527  AVPacket *packet = NULL;
528  unsigned int stream_index;
529  unsigned int i;
530 
531  if (argc != 3) {
532  av_log(NULL, AV_LOG_ERROR, "Usage: %s <input file> <output file>\n", argv[0]);
533  return 1;
534  }
535 
536  if ((ret = open_input_file(argv[1])) < 0)
537  goto end;
538  if ((ret = open_output_file(argv[2])) < 0)
539  goto end;
540  if ((ret = init_filters()) < 0)
541  goto end;
542  if (!(packet = av_packet_alloc()))
543  goto end;
544 
545  /* read all packets */
546  while (1) {
547  if ((ret = av_read_frame(ifmt_ctx, packet)) < 0)
548  break;
549  stream_index = packet->stream_index;
550  av_log(NULL, AV_LOG_DEBUG, "Demuxer gave frame of stream_index %u\n",
551  stream_index);
552 
553  if (filter_ctx[stream_index].filter_graph) {
554  StreamContext *stream = &stream_ctx[stream_index];
555 
556  av_log(NULL, AV_LOG_DEBUG, "Going to reencode&filter the frame\n");
557 
558  ret = avcodec_send_packet(stream->dec_ctx, packet);
559  if (ret < 0) {
560  av_log(NULL, AV_LOG_ERROR, "Decoding failed\n");
561  break;
562  }
563 
564  while (ret >= 0) {
565  ret = avcodec_receive_frame(stream->dec_ctx, stream->dec_frame);
566  if (ret == AVERROR_EOF || ret == AVERROR(EAGAIN))
567  break;
568  else if (ret < 0)
569  goto end;
570 
571  stream->dec_frame->pts = stream->dec_frame->best_effort_timestamp;
572  ret = filter_encode_write_frame(stream->dec_frame, stream_index);
573  if (ret < 0)
574  goto end;
575  }
576  } else {
577  /* remux this frame without reencoding */
578  av_packet_rescale_ts(packet,
579  ifmt_ctx->streams[stream_index]->time_base,
580  ofmt_ctx->streams[stream_index]->time_base);
581 
583  if (ret < 0)
584  goto end;
585  }
586  av_packet_unref(packet);
587  }
588 
589  /* flush decoders, filters and encoders */
590  for (i = 0; i < ifmt_ctx->nb_streams; i++) {
591  StreamContext *stream;
592 
593  if (!filter_ctx[i].filter_graph)
594  continue;
595 
596  stream = &stream_ctx[i];
597 
598  av_log(NULL, AV_LOG_INFO, "Flushing stream %u decoder\n", i);
599 
600  /* flush decoder */
601  ret = avcodec_send_packet(stream->dec_ctx, NULL);
602  if (ret < 0) {
603  av_log(NULL, AV_LOG_ERROR, "Flushing decoding failed\n");
604  goto end;
605  }
606 
607  while (ret >= 0) {
608  ret = avcodec_receive_frame(stream->dec_ctx, stream->dec_frame);
609  if (ret == AVERROR_EOF)
610  break;
611  else if (ret < 0)
612  goto end;
613 
614  stream->dec_frame->pts = stream->dec_frame->best_effort_timestamp;
616  if (ret < 0)
617  goto end;
618  }
619 
620  /* flush filter */
622  if (ret < 0) {
623  av_log(NULL, AV_LOG_ERROR, "Flushing filter failed\n");
624  goto end;
625  }
626 
627  /* flush encoder */
628  ret = flush_encoder(i);
629  if (ret < 0) {
630  av_log(NULL, AV_LOG_ERROR, "Flushing encoder failed\n");
631  goto end;
632  }
633  }
634 
636 end:
637  av_packet_free(&packet);
638  for (i = 0; i < ifmt_ctx->nb_streams; i++) {
641  avcodec_free_context(&stream_ctx[i].enc_ctx);
644  av_packet_free(&filter_ctx[i].enc_pkt);
645  av_frame_free(&filter_ctx[i].filtered_frame);
646  }
647 
648  av_frame_free(&stream_ctx[i].dec_frame);
649  }
656 
657  if (ret < 0)
658  av_log(NULL, AV_LOG_ERROR, "Error occurred: %s\n", av_err2str(ret));
659 
660  return ret ? 1 : 0;
661 }
AV_OPT_SEARCH_CHILDREN
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:533
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: packet.c:427
AVCodec
AVCodec.
Definition: codec.h:187
dec_ctx
static AVCodecContext * dec_ctx
Definition: decode_filter_audio.c:47
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:541
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1050
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
FilteringContext::filtered_frame
AVFrame * filtered_frame
Definition: transcode.c:50
stream_ctx
static StreamContext * stream_ctx
Definition: transcode.c:60
AVCodec::pix_fmts
enum AVPixelFormat * pix_fmts
array of supported pixel formats, or NULL if unknown, array is terminated by -1
Definition: codec.h:209
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:160
avcodec_find_encoder
const AVCodec * avcodec_find_encoder(enum AVCodecID id)
Find a registered encoder with a matching codec ID.
Definition: allcodecs.c:960
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
pixdesc.h
ofmt_ctx
static AVFormatContext * ofmt_ctx
Definition: transcode.c:43
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1323
AVFrame::pts
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:486
avio_open
int avio_open(AVIOContext **s, const char *filename, int flags)
Create and initialize a AVIOContext for accessing the resource indicated by url.
Definition: avio.c:497
filter
void(* filter)(uint8_t *src, int stride, int qscale)
Definition: h263dsp.c:29
AVChannelLayout::order
enum AVChannelOrder order
Channel order used in this layout.
Definition: channel_layout.h:316
av_read_frame
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: demux.c:1538
AVERROR_UNKNOWN
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:73
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:321
StreamContext::dec_frame
AVFrame * dec_frame
Definition: transcode.c:58
av_packet_free
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: packet.c:74
AV_CODEC_FLAG_GLOBAL_HEADER
#define AV_CODEC_FLAG_GLOBAL_HEADER
Place global headers in extradata instead of every keyframe.
Definition: avcodec.h:338
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:116
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:560
avformat_close_input
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: demux.c:363
FilteringContext
Definition: transcode.c:44
avfilter_graph_create_filter
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt, const char *name, const char *args, void *opaque, AVFilterGraph *graph_ctx)
Create and add a filter instance into an existing graph.
Definition: avfiltergraph.c:137
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:1065
AVCodec::sample_fmts
enum AVSampleFormat * sample_fmts
array of supported sample formats, or NULL if unknown, array is terminated by -1
Definition: codec.h:211
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:82
filter_ctx
static FilteringContext * filter_ctx
Definition: transcode.c:52
AVCodecContext::flags
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:502
av_opt_set
int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
Definition: opt.c:747
AVRational::num
int num
Numerator.
Definition: rational.h:59
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:148
avfilter_inout_free
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
Definition: graphparser.c:76
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_dump_format
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,...
Definition: dump.c:770
avformat_open_input
int avformat_open_input(AVFormatContext **ps, const char *url, const AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: demux.c:215
av_channel_layout_describe
int av_channel_layout_describe(const AVChannelLayout *channel_layout, char *buf, size_t buf_size)
Get a human-readable string describing the channel layout properties.
Definition: channel_layout.c:648
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:149
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_CHANNEL_ORDER_UNSPEC
@ AV_CHANNEL_ORDER_UNSPEC
Only the channel count is specified, without any further information about the channel order.
Definition: channel_layout.h:116
av_buffersink_get_frame
int attribute_align_arg av_buffersink_get_frame(AVFilterContext *ctx, AVFrame *frame)
Get a frame with filtered data from sink and put it in frame.
Definition: buffersink.c:68
avcodec_receive_frame
int attribute_align_arg avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder or encoder (when the AV_CODEC_FLAG_RECON_FRAME flag is used...
Definition: avcodec.c:698
av_buffersink_get_time_base
AVRational av_buffersink_get_time_base(const AVFilterContext *ctx)
AVIO_FLAG_WRITE
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:618
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:201
av_rescale_q
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
av_get_sample_fmt_name
const char * av_get_sample_fmt_name(enum AVSampleFormat sample_fmt)
Return the name of sample_fmt, or NULL if sample_fmt is not recognized.
Definition: samplefmt.c:51
avformat_write_header
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:487
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:455
FilteringContext::buffersrc_ctx
AVFilterContext * buffersrc_ctx
Definition: transcode.c:46
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:631
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const struct AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
avfilter_graph_config
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
Check validity and configure all the links and formats in the graph.
Definition: avfiltergraph.c:1243
AVStream::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:782
NULL
#define NULL
Definition: coverity.c:32
av_opt_set_bin
int av_opt_set_bin(void *obj, const char *name, const uint8_t *val, int len, int search_flags)
Definition: opt.c:814
avcodec_free_context
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
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1297
flush
void(* flush)(AVBSFContext *ctx)
Definition: dts2pts.c:368
avfilter_inout_alloc
AVFilterInOut * avfilter_inout_alloc(void)
Allocate a single AVFilterInOut entry.
Definition: graphparser.c:71
avcodec_open2
int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:142
AVFilterGraph
Definition: avfilter.h:813
inputs
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
Definition: filter_design.txt:243
avcodec_find_decoder
const AVCodec * avcodec_find_decoder(enum AVCodecID id)
Find a registered decoder with a matching codec ID.
Definition: allcodecs.c:965
AVFrame::best_effort_timestamp
int64_t best_effort_timestamp
frame timestamp estimated using various heuristics, in stream time base
Definition: frame.h:673
AVFormatContext::nb_streams
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1311
StreamContext
Definition: transcode.c:54
AVOutputFormat::flags
int flags
can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS,...
Definition: avformat.h:529
AVCodecContext::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avcodec.h:544
avformat_find_stream_info
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: demux.c:2516
ifmt_ctx
static AVFormatContext * ifmt_ctx
Definition: transcode.c:42
av_err2str
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:122
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1057
AVCodecContext::pkt_timebase
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are expressed.
Definition: avcodec.h:551
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
AVFrame::time_base
AVRational time_base
Time base for the timestamps in this frame.
Definition: frame.h:501
AVFMT_NOFILE
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:468
AVMEDIA_TYPE_UNKNOWN
@ AVMEDIA_TYPE_UNKNOWN
Usually treated as AVMEDIA_TYPE_DATA.
Definition: avutil.h:200
AV_PICTURE_TYPE_NONE
@ AV_PICTURE_TYPE_NONE
Undefined.
Definition: avutil.h:278
FilteringContext::enc_pkt
AVPacket * enc_pkt
Definition: transcode.c:49
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: packet.c:63
av_packet_rescale_ts
void av_packet_rescale_ts(AVPacket *pkt, AVRational src_tb, AVRational dst_tb)
Convert valid timing fields (timestamps / durations) in a packet from one timebase to another.
Definition: packet.c:531
AV_LOG_INFO
#define AV_LOG_INFO
Standard information.
Definition: log.h:191
buffersink.h
buffersink_ctx
AVFilterContext * buffersink_ctx
Definition: decode_filter_audio.c:48
av_channel_layout_default
void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels)
Get the default channel layout for a given number of channels.
Definition: channel_layout.c:834
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:696
flush_encoder
static int flush_encoder(unsigned int stream_index)
Definition: transcode.c:514
av_write_trailer
int av_write_trailer(AVFormatContext *s)
Write the stream trailer to an output media file and free the file private data.
Definition: mux.c:1295
StreamContext::dec_ctx
AVCodecContext * dec_ctx
Definition: transcode.c:55
AVFMT_GLOBALHEADER
#define AVFMT_GLOBALHEADER
Format wants global header.
Definition: avformat.h:478
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
avfilter_graph_parse_ptr
int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters, AVFilterInOut **inputs, AVFilterInOut **outputs, void *log_ctx)
Add a graph described by a string to a graph.
Definition: graphparser.c:919
init_filter
static int init_filter(FilteringContext *fctx, AVCodecContext *dec_ctx, AVCodecContext *enc_ctx, const char *filter_spec)
Definition: transcode.c:245
encode_write_frame
static int encode_write_frame(unsigned int stream_index, int flush)
Definition: transcode.c:433
av_buffersrc_add_frame_flags
int attribute_align_arg av_buffersrc_add_frame_flags(AVFilterContext *ctx, AVFrame *frame, int flags)
Add a frame to the buffer source.
Definition: buffersrc.c:191
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:31
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:606
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
av_inv_q
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:39
AVCodecContext::height
int height
Definition: avcodec.h:618
filter_encode_write_frame
static int filter_encode_write_frame(AVFrame *frame, unsigned int stream_index)
Definition: transcode.c:474
avcodec_send_frame
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
Definition: encode.c:508
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:657
av_calloc
void * av_calloc(size_t nmemb, size_t size)
Definition: mem.c:264
outputs
static const AVFilterPad outputs[]
Definition: af_aap.c:311
avcodec.h
AVFilter
Filter definition.
Definition: avfilter.h:166
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
AV_LOG_FATAL
#define AV_LOG_FATAL
Something went wrong and recovery is not possible.
Definition: log.h:174
av_guess_frame_rate
AVRational av_guess_frame_rate(AVFormatContext *format, AVStream *st, AVFrame *frame)
Guess the frame rate, based on both the container and codec information.
Definition: avformat.c:750
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AVFormatContext::oformat
const struct AVOutputFormat * oformat
The output container format.
Definition: avformat.h:1274
avformat.h
StreamContext::enc_ctx
AVCodecContext * enc_ctx
Definition: transcode.c:56
AVCodecContext
main external API structure.
Definition: avcodec.h:445
channel_layout.h
init_filters
static int init_filters(void)
Definition: transcode.c:395
AVRational::den
int den
Denominator.
Definition: rational.h:60
avformat_free_context
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
Definition: avformat.c:141
AV_CODEC_CAP_DELAY
#define AV_CODEC_CAP_DELAY
Encoder or decoder requires flushing with NULL input at the end in order to give the complete and cor...
Definition: codec.h:76
AVPacket::stream_index
int stream_index
Definition: packet.h:522
AVFilterContext
An instance of a filter.
Definition: avfilter.h:407
av_channel_layout_copy
int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src)
Make a copy of a channel layout.
Definition: channel_layout.c:444
AVERROR_DECODER_NOT_FOUND
#define AVERROR_DECODER_NOT_FOUND
Decoder not found.
Definition: error.h:54
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:453
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:272
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
mem.h
main
int main(int argc, char **argv)
Definition: transcode.c:524
avcodec_parameters_from_context
int avcodec_parameters_from_context(struct AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:137
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:497
filter_graph
AVFilterGraph * filter_graph
Definition: decode_filter_audio.c:50
avio_closep
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: avio.c:649
av_interleaved_write_frame
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt)
Write a packet to an output media file ensuring correct interleaving.
Definition: mux.c:1280
FilteringContext::buffersink_ctx
AVFilterContext * buffersink_ctx
Definition: transcode.c:45
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:618
open_output_file
static int open_output_file(const char *filename)
Definition: transcode.c:129
open_input_file
static int open_input_file(const char *filename)
Definition: transcode.c:62
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
avformat_alloc_output_context2
int avformat_alloc_output_context2(AVFormatContext **ctx, const AVOutputFormat *oformat, const char *format_name, const char *filename)
Allocate an AVFormatContext for an output format.
Definition: mux.c:94
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:956
snprintf
#define snprintf
Definition: snprintf.h:34
FilteringContext::filter_graph
AVFilterGraph * filter_graph
Definition: transcode.c:47
buffersrc.h
AVCodecContext::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel.
Definition: avcodec.h:642
avcodec_parameters_copy
int avcodec_parameters_copy(AVCodecParameters *dst, const AVCodecParameters *src)
Copy the contents of src to dst.
Definition: codec_par.c:106
buffersrc_ctx
AVFilterContext * buffersrc_ctx
Definition: decode_filter_audio.c:49