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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 }, 2, INT_MAX, V|A|F},
63  { "v", "specify the number of video streams",
64  OFFSET(nb_streams[AVMEDIA_TYPE_VIDEO]),
65  AV_OPT_TYPE_INT, { .i64 = 1 }, 0, INT_MAX, V|F },
66  { "a", "specify the number of audio streams",
67  OFFSET(nb_streams[AVMEDIA_TYPE_AUDIO]),
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, A|A|F},
72  { 0 }
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  /* possible enhancement: unsafe mode, do not check */
138  if (outlink->w != inlink->w ||
139  outlink->h != inlink->h ||
140  outlink->sample_aspect_ratio.num != inlink->sample_aspect_ratio.num ||
141  outlink->sample_aspect_ratio.den != inlink->sample_aspect_ratio.den) {
142  av_log(ctx, AV_LOG_ERROR, "Input link %s parameters "
143  "(size %dx%d, SAR %d:%d) do not match the corresponding "
144  "output link %s parameters (%dx%d, SAR %d:%d)\n",
145  ctx->input_pads[in_no].name, inlink->w, inlink->h,
146  inlink->sample_aspect_ratio.num,
147  inlink->sample_aspect_ratio.den,
148  ctx->input_pads[out_no].name, outlink->w, outlink->h,
149  outlink->sample_aspect_ratio.num,
150  outlink->sample_aspect_ratio.den);
151  if (!cat->unsafe)
152  return AVERROR(EINVAL);
153  }
154  }
155 
156  return 0;
157 }
158 
159 static int push_frame(AVFilterContext *ctx, unsigned in_no, AVFrame *buf)
160 {
161  ConcatContext *cat = ctx->priv;
162  unsigned out_no = in_no % ctx->nb_outputs;
163  AVFilterLink * inlink = ctx-> inputs[ in_no];
164  AVFilterLink *outlink = ctx->outputs[out_no];
165  struct concat_in *in = &cat->in[in_no];
166 
167  buf->pts = av_rescale_q(buf->pts, inlink->time_base, outlink->time_base);
168  in->pts = buf->pts;
169  in->nb_frames++;
170  /* add duration to input PTS */
171  if (inlink->sample_rate)
172  /* use number of audio samples */
173  in->pts += av_rescale_q(buf->nb_samples,
174  (AVRational){ 1, inlink->sample_rate },
175  outlink->time_base);
176  else if (in->nb_frames >= 2)
177  /* use mean duration */
178  in->pts = av_rescale(in->pts, in->nb_frames, in->nb_frames - 1);
179 
180  buf->pts += cat->delta_ts;
181  return ff_filter_frame(outlink, buf);
182 }
183 
184 static int process_frame(AVFilterLink *inlink, AVFrame *buf)
185 {
186  AVFilterContext *ctx = inlink->dst;
187  ConcatContext *cat = ctx->priv;
188  unsigned in_no = FF_INLINK_IDX(inlink);
189 
190  if (in_no < cat->cur_idx) {
191  av_log(ctx, AV_LOG_ERROR, "Frame after EOF on input %s\n",
192  ctx->input_pads[in_no].name);
193  av_frame_free(&buf);
194  } else if (in_no >= cat->cur_idx + ctx->nb_outputs) {
195  ff_bufqueue_add(ctx, &cat->in[in_no].queue, buf);
196  } else {
197  return push_frame(ctx, in_no, buf);
198  }
199  return 0;
200 }
201 
202 static AVFrame *get_video_buffer(AVFilterLink *inlink, int w, int h)
203 {
204  AVFilterContext *ctx = inlink->dst;
205  unsigned in_no = FF_INLINK_IDX(inlink);
206  AVFilterLink *outlink = ctx->outputs[in_no % ctx->nb_outputs];
207 
208  return ff_get_video_buffer(outlink, w, h);
209 }
210 
211 static AVFrame *get_audio_buffer(AVFilterLink *inlink, int nb_samples)
212 {
213  AVFilterContext *ctx = inlink->dst;
214  unsigned in_no = FF_INLINK_IDX(inlink);
215  AVFilterLink *outlink = ctx->outputs[in_no % ctx->nb_outputs];
216 
217  return ff_get_audio_buffer(outlink, nb_samples);
218 }
219 
220 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
221 {
222  return process_frame(inlink, buf);
223 }
224 
225 static void close_input(AVFilterContext *ctx, unsigned in_no)
226 {
227  ConcatContext *cat = ctx->priv;
228 
229  cat->in[in_no].eof = 1;
230  cat->nb_in_active--;
231  av_log(ctx, AV_LOG_VERBOSE, "EOF on %s, %d streams left in segment.\n",
232  ctx->input_pads[in_no].name, cat->nb_in_active);
233 }
234 
235 static void find_next_delta_ts(AVFilterContext *ctx, int64_t *seg_delta)
236 {
237  ConcatContext *cat = ctx->priv;
238  unsigned i = cat->cur_idx;
239  unsigned imax = i + ctx->nb_outputs;
240  int64_t pts;
241 
242  pts = cat->in[i++].pts;
243  for (; i < imax; i++)
244  pts = FFMAX(pts, cat->in[i].pts);
245  cat->delta_ts += pts;
246  *seg_delta = pts;
247 }
248 
249 static int send_silence(AVFilterContext *ctx, unsigned in_no, unsigned out_no,
250  int64_t seg_delta)
251 {
252  ConcatContext *cat = ctx->priv;
253  AVFilterLink *outlink = ctx->outputs[out_no];
254  int64_t base_pts = cat->in[in_no].pts + cat->delta_ts - seg_delta;
255  int64_t nb_samples, sent = 0;
256  int frame_nb_samples, ret;
257  AVRational rate_tb = { 1, ctx->inputs[in_no]->sample_rate };
258  AVFrame *buf;
260 
261  if (!rate_tb.den)
262  return AVERROR_BUG;
263  nb_samples = av_rescale_q(seg_delta - cat->in[in_no].pts,
264  outlink->time_base, rate_tb);
265  frame_nb_samples = FFMAX(9600, rate_tb.den / 5); /* arbitrary */
266  while (nb_samples) {
267  frame_nb_samples = FFMIN(frame_nb_samples, nb_samples);
268  buf = ff_get_audio_buffer(outlink, frame_nb_samples);
269  if (!buf)
270  return AVERROR(ENOMEM);
271  av_samples_set_silence(buf->extended_data, 0, frame_nb_samples,
272  nb_channels, outlink->format);
273  buf->pts = base_pts + av_rescale_q(sent, rate_tb, outlink->time_base);
274  ret = ff_filter_frame(outlink, buf);
275  if (ret < 0)
276  return ret;
277  sent += frame_nb_samples;
278  nb_samples -= frame_nb_samples;
279  }
280  return 0;
281 }
282 
284 {
285  int ret;
286  ConcatContext *cat = ctx->priv;
287  unsigned str, str_max;
288  int64_t seg_delta;
289 
290  find_next_delta_ts(ctx, &seg_delta);
291  cat->cur_idx += ctx->nb_outputs;
292  cat->nb_in_active = ctx->nb_outputs;
293  av_log(ctx, AV_LOG_VERBOSE, "Segment finished at pts=%"PRId64"\n",
294  cat->delta_ts);
295 
296  if (cat->cur_idx < ctx->nb_inputs) {
297  /* pad audio streams with silence */
298  str = cat->nb_streams[AVMEDIA_TYPE_VIDEO];
299  str_max = str + cat->nb_streams[AVMEDIA_TYPE_AUDIO];
300  for (; str < str_max; str++) {
301  ret = send_silence(ctx, cat->cur_idx - ctx->nb_outputs + str, str,
302  seg_delta);
303  if (ret < 0)
304  return ret;
305  }
306  /* flush queued buffers */
307  /* possible enhancement: flush in PTS order */
308  str_max = cat->cur_idx + ctx->nb_outputs;
309  for (str = cat->cur_idx; str < str_max; str++) {
310  while (cat->in[str].queue.available) {
311  ret = push_frame(ctx, str, ff_bufqueue_get(&cat->in[str].queue));
312  if (ret < 0)
313  return ret;
314  }
315  }
316  }
317  return 0;
318 }
319 
320 static int request_frame(AVFilterLink *outlink)
321 {
322  AVFilterContext *ctx = outlink->src;
323  ConcatContext *cat = ctx->priv;
324  unsigned out_no = FF_OUTLINK_IDX(outlink);
325  unsigned in_no = out_no + cat->cur_idx;
326  unsigned str, str_max;
327  int ret;
328 
329  while (1) {
330  if (in_no >= ctx->nb_inputs)
331  return AVERROR_EOF;
332  if (!cat->in[in_no].eof) {
333  ret = ff_request_frame(ctx->inputs[in_no]);
334  if (ret != AVERROR_EOF)
335  return ret;
336  close_input(ctx, in_no);
337  }
338  /* cycle on all inputs to finish the segment */
339  /* possible enhancement: request in PTS order */
340  str_max = cat->cur_idx + ctx->nb_outputs - 1;
341  for (str = cat->cur_idx; cat->nb_in_active;
342  str = str == str_max ? cat->cur_idx : str + 1) {
343  if (cat->in[str].eof)
344  continue;
345  ret = ff_request_frame(ctx->inputs[str]);
346  if (ret == AVERROR_EOF)
347  close_input(ctx, str);
348  else if (ret < 0)
349  return ret;
350  }
351  ret = flush_segment(ctx);
352  if (ret < 0)
353  return ret;
354  in_no += ctx->nb_outputs;
355  }
356 }
357 
358 static av_cold int init(AVFilterContext *ctx)
359 {
360  ConcatContext *cat = ctx->priv;
361  unsigned seg, type, str;
362 
363  /* create input pads */
364  for (seg = 0; seg < cat->nb_segments; seg++) {
365  for (type = 0; type < TYPE_ALL; type++) {
366  for (str = 0; str < cat->nb_streams[type]; str++) {
367  AVFilterPad pad = {
368  .type = type,
369  .get_video_buffer = get_video_buffer,
370  .get_audio_buffer = get_audio_buffer,
371  .filter_frame = filter_frame,
372  };
373  pad.name = av_asprintf("in%d:%c%d", seg, "va"[type], str);
374  ff_insert_inpad(ctx, ctx->nb_inputs, &pad);
375  }
376  }
377  }
378  /* create output pads */
379  for (type = 0; type < TYPE_ALL; type++) {
380  for (str = 0; str < cat->nb_streams[type]; str++) {
381  AVFilterPad pad = {
382  .type = type,
383  .config_props = config_output,
384  .request_frame = request_frame,
385  };
386  pad.name = av_asprintf("out:%c%d", "va"[type], str);
387  ff_insert_outpad(ctx, ctx->nb_outputs, &pad);
388  }
389  }
390 
391  cat->in = av_calloc(ctx->nb_inputs, sizeof(*cat->in));
392  if (!cat->in)
393  return AVERROR(ENOMEM);
394  cat->nb_in_active = ctx->nb_outputs;
395  return 0;
396 }
397 
398 static av_cold void uninit(AVFilterContext *ctx)
399 {
400  ConcatContext *cat = ctx->priv;
401  unsigned i;
402 
403  for (i = 0; i < ctx->nb_inputs; i++) {
404  av_freep(&ctx->input_pads[i].name);
405  ff_bufqueue_discard_all(&cat->in[i].queue);
406  }
407  for (i = 0; i < ctx->nb_outputs; i++)
408  av_freep(&ctx->output_pads[i].name);
409  av_free(cat->in);
410 }
411 
413  .name = "concat",
414  .description = NULL_IF_CONFIG_SMALL("Concatenate audio and video streams."),
415  .init = init,
416  .uninit = uninit,
417  .query_formats = query_formats,
418  .priv_size = sizeof(ConcatContext),
419  .inputs = NULL,
420  .outputs = NULL,
421  .priv_class = &concat_class,
423 };