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avf_concat.c
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1 /*
2  * Copyright (c) 2012 Nicolas George
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
14  * See the GNU Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public License
17  * along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * concat audio-video filter
24  */
25 
26 #include "libavutil/avassert.h"
27 #include "libavutil/avstring.h"
29 #include "libavutil/opt.h"
30 #include "avfilter.h"
31 #define FF_BUFQUEUE_SIZE 256
32 #include "bufferqueue.h"
33 #include "internal.h"
34 #include "video.h"
35 #include "audio.h"
36 
37 #define TYPE_ALL 2
38 
39 typedef struct {
40  const AVClass *class;
41  unsigned nb_streams[TYPE_ALL]; /**< number of out streams of each type */
42  unsigned nb_segments;
43  unsigned cur_idx; /**< index of the first input of current segment */
44  int64_t delta_ts; /**< timestamp to add to produce output timestamps */
45  unsigned nb_in_active; /**< number of active inputs in current segment */
46  unsigned unsafe;
47  struct concat_in {
48  int64_t pts;
49  int64_t nb_frames;
50  unsigned eof;
51  struct FFBufQueue queue;
52  } *in;
54 
55 #define OFFSET(x) offsetof(ConcatContext, x)
56 #define A AV_OPT_FLAG_AUDIO_PARAM
57 #define F AV_OPT_FLAG_FILTERING_PARAM
58 #define V AV_OPT_FLAG_VIDEO_PARAM
59 
60 static const AVOption concat_options[] = {
61  { "n", "specify the number of segments", OFFSET(nb_segments),
62  AV_OPT_TYPE_INT, { .i64 = 2 }, 1, INT_MAX, V|A|F},
63  { "v", "specify the number of video streams",
65  AV_OPT_TYPE_INT, { .i64 = 1 }, 0, INT_MAX, V|F },
66  { "a", "specify the number of audio streams",
68  AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, A|F},
69  { "unsafe", "enable unsafe mode",
70  OFFSET(unsafe),
71  AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, V|A|F},
72  { NULL }
73 };
74 
75 AVFILTER_DEFINE_CLASS(concat);
76 
78 {
79  ConcatContext *cat = ctx->priv;
80  unsigned type, nb_str, idx0 = 0, idx, str, seg;
81  AVFilterFormats *formats, *rates = NULL;
83 
84  for (type = 0; type < TYPE_ALL; type++) {
85  nb_str = cat->nb_streams[type];
86  for (str = 0; str < nb_str; str++) {
87  idx = idx0;
88 
89  /* Set the output formats */
90  formats = ff_all_formats(type);
91  if (!formats)
92  return AVERROR(ENOMEM);
93  ff_formats_ref(formats, &ctx->outputs[idx]->in_formats);
94  if (type == AVMEDIA_TYPE_AUDIO) {
95  rates = ff_all_samplerates();
96  if (!rates)
97  return AVERROR(ENOMEM);
98  ff_formats_ref(rates, &ctx->outputs[idx]->in_samplerates);
99  layouts = ff_all_channel_layouts();
100  if (!layouts)
101  return AVERROR(ENOMEM);
102  ff_channel_layouts_ref(layouts, &ctx->outputs[idx]->in_channel_layouts);
103  }
104 
105  /* Set the same formats for each corresponding input */
106  for (seg = 0; seg < cat->nb_segments; seg++) {
107  ff_formats_ref(formats, &ctx->inputs[idx]->out_formats);
108  if (type == AVMEDIA_TYPE_AUDIO) {
109  ff_formats_ref(rates, &ctx->inputs[idx]->out_samplerates);
110  ff_channel_layouts_ref(layouts, &ctx->inputs[idx]->out_channel_layouts);
111  }
112  idx += ctx->nb_outputs;
113  }
114 
115  idx0++;
116  }
117  }
118  return 0;
119 }
120 
121 static int config_output(AVFilterLink *outlink)
122 {
123  AVFilterContext *ctx = outlink->src;
124  ConcatContext *cat = ctx->priv;
125  unsigned out_no = FF_OUTLINK_IDX(outlink);
126  unsigned in_no = out_no, seg;
127  AVFilterLink *inlink = ctx->inputs[in_no];
128 
129  /* enhancement: find a common one */
130  outlink->time_base = AV_TIME_BASE_Q;
131  outlink->w = inlink->w;
132  outlink->h = inlink->h;
133  outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
134  outlink->format = inlink->format;
135  for (seg = 1; seg < cat->nb_segments; seg++) {
136  inlink = ctx->inputs[in_no += ctx->nb_outputs];
137  if (!outlink->sample_aspect_ratio.num)
138  outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
139  /* possible enhancement: unsafe mode, do not check */
140  if (outlink->w != inlink->w ||
141  outlink->h != inlink->h ||
142  outlink->sample_aspect_ratio.num != inlink->sample_aspect_ratio.num &&
143  inlink->sample_aspect_ratio.num ||
144  outlink->sample_aspect_ratio.den != inlink->sample_aspect_ratio.den) {
145  av_log(ctx, AV_LOG_ERROR, "Input link %s parameters "
146  "(size %dx%d, SAR %d:%d) do not match the corresponding "
147  "output link %s parameters (%dx%d, SAR %d:%d)\n",
148  ctx->input_pads[in_no].name, inlink->w, inlink->h,
149  inlink->sample_aspect_ratio.num,
150  inlink->sample_aspect_ratio.den,
151  ctx->input_pads[out_no].name, outlink->w, outlink->h,
152  outlink->sample_aspect_ratio.num,
153  outlink->sample_aspect_ratio.den);
154  if (!cat->unsafe)
155  return AVERROR(EINVAL);
156  }
157  }
158 
159  return 0;
160 }
161 
162 static int push_frame(AVFilterContext *ctx, unsigned in_no, AVFrame *buf)
163 {
164  ConcatContext *cat = ctx->priv;
165  unsigned out_no = in_no % ctx->nb_outputs;
166  AVFilterLink * inlink = ctx-> inputs[ in_no];
167  AVFilterLink *outlink = ctx->outputs[out_no];
168  struct concat_in *in = &cat->in[in_no];
169 
170  buf->pts = av_rescale_q(buf->pts, inlink->time_base, outlink->time_base);
171  in->pts = buf->pts;
172  in->nb_frames++;
173  /* add duration to input PTS */
174  if (inlink->sample_rate)
175  /* use number of audio samples */
176  in->pts += av_rescale_q(buf->nb_samples,
177  av_make_q(1, inlink->sample_rate),
178  outlink->time_base);
179  else if (in->nb_frames >= 2)
180  /* use mean duration */
181  in->pts = av_rescale(in->pts, in->nb_frames, in->nb_frames - 1);
182 
183  buf->pts += cat->delta_ts;
184  return ff_filter_frame(outlink, buf);
185 }
186 
187 static int process_frame(AVFilterLink *inlink, AVFrame *buf)
188 {
189  AVFilterContext *ctx = inlink->dst;
190  ConcatContext *cat = ctx->priv;
191  unsigned in_no = FF_INLINK_IDX(inlink);
192 
193  if (in_no < cat->cur_idx) {
194  av_log(ctx, AV_LOG_ERROR, "Frame after EOF on input %s\n",
195  ctx->input_pads[in_no].name);
196  av_frame_free(&buf);
197  } else if (in_no >= cat->cur_idx + ctx->nb_outputs) {
198  ff_bufqueue_add(ctx, &cat->in[in_no].queue, buf);
199  } else {
200  return push_frame(ctx, in_no, buf);
201  }
202  return 0;
203 }
204 
205 static AVFrame *get_video_buffer(AVFilterLink *inlink, int w, int h)
206 {
207  AVFilterContext *ctx = inlink->dst;
208  unsigned in_no = FF_INLINK_IDX(inlink);
209  AVFilterLink *outlink = ctx->outputs[in_no % ctx->nb_outputs];
210 
211  return ff_get_video_buffer(outlink, w, h);
212 }
213 
214 static AVFrame *get_audio_buffer(AVFilterLink *inlink, int nb_samples)
215 {
216  AVFilterContext *ctx = inlink->dst;
217  unsigned in_no = FF_INLINK_IDX(inlink);
218  AVFilterLink *outlink = ctx->outputs[in_no % ctx->nb_outputs];
219 
220  return ff_get_audio_buffer(outlink, nb_samples);
221 }
222 
223 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
224 {
225  return process_frame(inlink, buf);
226 }
227 
228 static void close_input(AVFilterContext *ctx, unsigned in_no)
229 {
230  ConcatContext *cat = ctx->priv;
231 
232  cat->in[in_no].eof = 1;
233  cat->nb_in_active--;
234  av_log(ctx, AV_LOG_VERBOSE, "EOF on %s, %d streams left in segment.\n",
235  ctx->input_pads[in_no].name, cat->nb_in_active);
236 }
237 
238 static void find_next_delta_ts(AVFilterContext *ctx, int64_t *seg_delta)
239 {
240  ConcatContext *cat = ctx->priv;
241  unsigned i = cat->cur_idx;
242  unsigned imax = i + ctx->nb_outputs;
243  int64_t pts;
244 
245  pts = cat->in[i++].pts;
246  for (; i < imax; i++)
247  pts = FFMAX(pts, cat->in[i].pts);
248  cat->delta_ts += pts;
249  *seg_delta = pts;
250 }
251 
252 static int send_silence(AVFilterContext *ctx, unsigned in_no, unsigned out_no,
253  int64_t seg_delta)
254 {
255  ConcatContext *cat = ctx->priv;
256  AVFilterLink *outlink = ctx->outputs[out_no];
257  int64_t base_pts = cat->in[in_no].pts + cat->delta_ts - seg_delta;
258  int64_t nb_samples, sent = 0;
259  int frame_nb_samples, ret;
260  AVRational rate_tb = { 1, ctx->inputs[in_no]->sample_rate };
261  AVFrame *buf;
263 
264  if (!rate_tb.den)
265  return AVERROR_BUG;
266  nb_samples = av_rescale_q(seg_delta - cat->in[in_no].pts,
267  outlink->time_base, rate_tb);
268  frame_nb_samples = FFMAX(9600, rate_tb.den / 5); /* arbitrary */
269  while (nb_samples) {
270  frame_nb_samples = FFMIN(frame_nb_samples, nb_samples);
271  buf = ff_get_audio_buffer(outlink, frame_nb_samples);
272  if (!buf)
273  return AVERROR(ENOMEM);
274  av_samples_set_silence(buf->extended_data, 0, frame_nb_samples,
275  nb_channels, outlink->format);
276  buf->pts = base_pts + av_rescale_q(sent, rate_tb, outlink->time_base);
277  ret = ff_filter_frame(outlink, buf);
278  if (ret < 0)
279  return ret;
280  sent += frame_nb_samples;
281  nb_samples -= frame_nb_samples;
282  }
283  return 0;
284 }
285 
287 {
288  int ret;
289  ConcatContext *cat = ctx->priv;
290  unsigned str, str_max;
291  int64_t seg_delta;
292 
293  find_next_delta_ts(ctx, &seg_delta);
294  cat->cur_idx += ctx->nb_outputs;
295  cat->nb_in_active = ctx->nb_outputs;
296  av_log(ctx, AV_LOG_VERBOSE, "Segment finished at pts=%"PRId64"\n",
297  cat->delta_ts);
298 
299  if (cat->cur_idx < ctx->nb_inputs) {
300  /* pad audio streams with silence */
301  str = cat->nb_streams[AVMEDIA_TYPE_VIDEO];
302  str_max = str + cat->nb_streams[AVMEDIA_TYPE_AUDIO];
303  for (; str < str_max; str++) {
304  ret = send_silence(ctx, cat->cur_idx - ctx->nb_outputs + str, str,
305  seg_delta);
306  if (ret < 0)
307  return ret;
308  }
309  /* flush queued buffers */
310  /* possible enhancement: flush in PTS order */
311  str_max = cat->cur_idx + ctx->nb_outputs;
312  for (str = cat->cur_idx; str < str_max; str++) {
313  while (cat->in[str].queue.available) {
314  ret = push_frame(ctx, str, ff_bufqueue_get(&cat->in[str].queue));
315  if (ret < 0)
316  return ret;
317  }
318  }
319  }
320  return 0;
321 }
322 
323 static int request_frame(AVFilterLink *outlink)
324 {
325  AVFilterContext *ctx = outlink->src;
326  ConcatContext *cat = ctx->priv;
327  unsigned out_no = FF_OUTLINK_IDX(outlink);
328  unsigned in_no = out_no + cat->cur_idx;
329  unsigned str, str_max;
330  int ret;
331 
332  while (1) {
333  if (in_no >= ctx->nb_inputs)
334  return AVERROR_EOF;
335  if (!cat->in[in_no].eof) {
336  ret = ff_request_frame(ctx->inputs[in_no]);
337  if (ret != AVERROR_EOF)
338  return ret;
339  close_input(ctx, in_no);
340  }
341  /* cycle on all inputs to finish the segment */
342  /* possible enhancement: request in PTS order */
343  str_max = cat->cur_idx + ctx->nb_outputs - 1;
344  for (str = cat->cur_idx; cat->nb_in_active;
345  str = str == str_max ? cat->cur_idx : str + 1) {
346  if (cat->in[str].eof)
347  continue;
348  ret = ff_request_frame(ctx->inputs[str]);
349  if (ret == AVERROR_EOF)
350  close_input(ctx, str);
351  else if (ret < 0)
352  return ret;
353  }
354  ret = flush_segment(ctx);
355  if (ret < 0)
356  return ret;
357  in_no += ctx->nb_outputs;
358  }
359 }
360 
361 static av_cold int init(AVFilterContext *ctx)
362 {
363  ConcatContext *cat = ctx->priv;
364  unsigned seg, type, str;
365 
366  /* create input pads */
367  for (seg = 0; seg < cat->nb_segments; seg++) {
368  for (type = 0; type < TYPE_ALL; type++) {
369  for (str = 0; str < cat->nb_streams[type]; str++) {
370  AVFilterPad pad = {
371  .type = type,
372  .get_video_buffer = get_video_buffer,
373  .get_audio_buffer = get_audio_buffer,
374  .filter_frame = filter_frame,
375  };
376  pad.name = av_asprintf("in%d:%c%d", seg, "va"[type], str);
377  ff_insert_inpad(ctx, ctx->nb_inputs, &pad);
378  }
379  }
380  }
381  /* create output pads */
382  for (type = 0; type < TYPE_ALL; type++) {
383  for (str = 0; str < cat->nb_streams[type]; str++) {
384  AVFilterPad pad = {
385  .type = type,
386  .config_props = config_output,
387  .request_frame = request_frame,
388  };
389  pad.name = av_asprintf("out:%c%d", "va"[type], str);
390  ff_insert_outpad(ctx, ctx->nb_outputs, &pad);
391  }
392  }
393 
394  cat->in = av_calloc(ctx->nb_inputs, sizeof(*cat->in));
395  if (!cat->in)
396  return AVERROR(ENOMEM);
397  cat->nb_in_active = ctx->nb_outputs;
398  return 0;
399 }
400 
401 static av_cold void uninit(AVFilterContext *ctx)
402 {
403  ConcatContext *cat = ctx->priv;
404  unsigned i;
405 
406  for (i = 0; i < ctx->nb_inputs; i++) {
407  av_freep(&ctx->input_pads[i].name);
408  ff_bufqueue_discard_all(&cat->in[i].queue);
409  }
410  for (i = 0; i < ctx->nb_outputs; i++)
411  av_freep(&ctx->output_pads[i].name);
412  av_freep(&cat->in);
413 }
414 
416  .name = "concat",
417  .description = NULL_IF_CONFIG_SMALL("Concatenate audio and video streams."),
418  .init = init,
419  .uninit = uninit,
420  .query_formats = query_formats,
421  .priv_size = sizeof(ConcatContext),
422  .inputs = NULL,
423  .outputs = NULL,
424  .priv_class = &concat_class,
426 };