Libav
af_join.c
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1 /*
2  *
3  * This file is part of Libav.
4  *
5  * Libav is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2.1 of the License, or (at your option) any later version.
9  *
10  * Libav is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public
16  * License along with Libav; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
28 #include "libavutil/avassert.h"
30 #include "libavutil/common.h"
31 #include "libavutil/opt.h"
32 
33 #include "audio.h"
34 #include "avfilter.h"
35 #include "formats.h"
36 #include "internal.h"
37 
38 typedef struct ChannelMap {
39  int input;
40  int in_channel_idx;
41  uint64_t in_channel;
42  uint64_t out_channel;
43 } ChannelMap;
44 
45 typedef struct JoinContext {
46  const AVClass *class;
47 
48  int inputs;
49  char *map;
51  uint64_t channel_layout;
52 
55 
60 
65 } JoinContext;
66 
67 #define OFFSET(x) offsetof(JoinContext, x)
68 #define A AV_OPT_FLAG_AUDIO_PARAM
69 static const AVOption join_options[] = {
70  { "inputs", "Number of input streams.", OFFSET(inputs), AV_OPT_TYPE_INT, { .i64 = 2 }, 1, INT_MAX, A },
71  { "channel_layout", "Channel layout of the "
72  "output stream.", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, {.str = "stereo"}, 0, 0, A },
73  { "map", "A comma-separated list of channels maps in the format "
74  "'input_stream.input_channel-output_channel.",
75  OFFSET(map), AV_OPT_TYPE_STRING, .flags = A },
76  { NULL },
77 };
78 
79 static const AVClass join_class = {
80  .class_name = "join filter",
81  .item_name = av_default_item_name,
82  .option = join_options,
83  .version = LIBAVUTIL_VERSION_INT,
84 };
85 
86 static int filter_frame(AVFilterLink *link, AVFrame *frame)
87 {
88  AVFilterContext *ctx = link->dst;
89  JoinContext *s = ctx->priv;
90  int i;
91 
92  for (i = 0; i < ctx->nb_inputs; i++)
93  if (link == ctx->inputs[i])
94  break;
95  av_assert0(i < ctx->nb_inputs);
96  av_assert0(!s->input_frames[i]);
97  s->input_frames[i] = frame;
98 
99  return 0;
100 }
101 
102 static int parse_maps(AVFilterContext *ctx)
103 {
104  JoinContext *s = ctx->priv;
105  char separator = '|';
106  char *cur = s->map;
107 
108 #if FF_API_OLD_FILTER_OPTS
109  if (cur && strchr(cur, ',')) {
110  av_log(ctx, AV_LOG_WARNING, "This syntax is deprecated, use '|' to "
111  "separate the mappings.\n");
112  separator = ',';
113  }
114 #endif
115 
116  while (cur && *cur) {
117  char *sep, *next, *p;
118  uint64_t in_channel = 0, out_channel = 0;
119  int input_idx, out_ch_idx, in_ch_idx;
120 
121  next = strchr(cur, separator);
122  if (next)
123  *next++ = 0;
124 
125  /* split the map into input and output parts */
126  if (!(sep = strchr(cur, '-'))) {
127  av_log(ctx, AV_LOG_ERROR, "Missing separator '-' in channel "
128  "map '%s'\n", cur);
129  return AVERROR(EINVAL);
130  }
131  *sep++ = 0;
132 
133 #define PARSE_CHANNEL(str, var, inout) \
134  if (!(var = av_get_channel_layout(str))) { \
135  av_log(ctx, AV_LOG_ERROR, "Invalid " inout " channel: %s.\n", str);\
136  return AVERROR(EINVAL); \
137  } \
138  if (av_get_channel_layout_nb_channels(var) != 1) { \
139  av_log(ctx, AV_LOG_ERROR, "Channel map describes more than one " \
140  inout " channel.\n"); \
141  return AVERROR(EINVAL); \
142  }
143 
144  /* parse output channel */
145  PARSE_CHANNEL(sep, out_channel, "output");
146  if (!(out_channel & s->channel_layout)) {
147  av_log(ctx, AV_LOG_ERROR, "Output channel '%s' is not present in "
148  "requested channel layout.\n", sep);
149  return AVERROR(EINVAL);
150  }
151 
153  out_channel);
154  if (s->channels[out_ch_idx].input >= 0) {
155  av_log(ctx, AV_LOG_ERROR, "Multiple maps for output channel "
156  "'%s'.\n", sep);
157  return AVERROR(EINVAL);
158  }
159 
160  /* parse input channel */
161  input_idx = strtol(cur, &cur, 0);
162  if (input_idx < 0 || input_idx >= s->inputs) {
163  av_log(ctx, AV_LOG_ERROR, "Invalid input stream index: %d.\n",
164  input_idx);
165  return AVERROR(EINVAL);
166  }
167 
168  if (*cur)
169  cur++;
170 
171  in_ch_idx = strtol(cur, &p, 0);
172  if (p == cur) {
173  /* channel specifier is not a number,
174  * try to parse as channel name */
175  PARSE_CHANNEL(cur, in_channel, "input");
176  }
177 
178  s->channels[out_ch_idx].input = input_idx;
179  if (in_channel)
180  s->channels[out_ch_idx].in_channel = in_channel;
181  else
182  s->channels[out_ch_idx].in_channel_idx = in_ch_idx;
183 
184  cur = next;
185  }
186  return 0;
187 }
188 
190 {
191  JoinContext *s = ctx->priv;
192  int ret, i;
193 
195  av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout '%s'.\n",
196  s->channel_layout_str);
197  ret = AVERROR(EINVAL);
198  goto fail;
199  }
200 
202  s->channels = av_mallocz(sizeof(*s->channels) * s->nb_channels);
203  s->buffers = av_mallocz(sizeof(*s->buffers) * s->nb_channels);
204  s->input_frames = av_mallocz(sizeof(*s->input_frames) * s->inputs);
205  if (!s->channels || !s->buffers|| !s->input_frames) {
206  ret = AVERROR(ENOMEM);
207  goto fail;
208  }
209 
210  for (i = 0; i < s->nb_channels; i++) {
212  s->channels[i].input = -1;
213  }
214 
215  if ((ret = parse_maps(ctx)) < 0)
216  goto fail;
217 
218  for (i = 0; i < s->inputs; i++) {
219  char name[32];
220  AVFilterPad pad = { 0 };
221 
222  snprintf(name, sizeof(name), "input%d", i);
223  pad.type = AVMEDIA_TYPE_AUDIO;
224  pad.name = av_strdup(name);
226 
227  pad.needs_fifo = 1;
228 
229  ff_insert_inpad(ctx, i, &pad);
230  }
231 
232 fail:
233  av_opt_free(s);
234  return ret;
235 }
236 
238 {
239  JoinContext *s = ctx->priv;
240  int i;
241 
242  for (i = 0; i < ctx->nb_inputs; i++) {
243  av_freep(&ctx->input_pads[i].name);
244  av_frame_free(&s->input_frames[i]);
245  }
246 
247  av_freep(&s->channels);
248  av_freep(&s->buffers);
249  av_freep(&s->input_frames);
250 }
251 
253 {
254  JoinContext *s = ctx->priv;
256  int i;
257 
260 
261  for (i = 0; i < ctx->nb_inputs; i++)
263  &ctx->inputs[i]->out_channel_layouts);
264 
267 
268  return 0;
269 }
270 
272  uint64_t *inputs)
273 {
274  int i;
275 
276  for (i = 0; i < ctx->nb_inputs; i++) {
277  AVFilterLink *link = ctx->inputs[i];
278 
279  if (ch->out_channel & link->channel_layout &&
280  !(ch->out_channel & inputs[i])) {
281  ch->input = i;
282  ch->in_channel = ch->out_channel;
283  inputs[i] |= ch->out_channel;
284  return;
285  }
286  }
287 }
288 
290  uint64_t *inputs)
291 {
292  int i;
293 
294  for (i = 0; i < ctx->nb_inputs; i++) {
295  AVFilterLink *link = ctx->inputs[i];
296 
297  if ((inputs[i] & link->channel_layout) != link->channel_layout) {
298  uint64_t unused = link->channel_layout & ~inputs[i];
299 
300  ch->input = i;
302  inputs[i] |= ch->in_channel;
303  return;
304  }
305  }
306 }
307 
308 static int join_config_output(AVFilterLink *outlink)
309 {
310  AVFilterContext *ctx = outlink->src;
311  JoinContext *s = ctx->priv;
312  uint64_t *inputs; // nth element tracks which channels are used from nth input
313  int i, ret = 0;
314 
315  /* initialize inputs to user-specified mappings */
316  if (!(inputs = av_mallocz(sizeof(*inputs) * ctx->nb_inputs)))
317  return AVERROR(ENOMEM);
318  for (i = 0; i < s->nb_channels; i++) {
319  ChannelMap *ch = &s->channels[i];
320  AVFilterLink *inlink;
321 
322  if (ch->input < 0)
323  continue;
324 
325  inlink = ctx->inputs[ch->input];
326 
327  if (!ch->in_channel)
329  ch->in_channel_idx);
330 
331  if (!(ch->in_channel & inlink->channel_layout)) {
332  av_log(ctx, AV_LOG_ERROR, "Requested channel %s is not present in "
333  "input stream #%d.\n", av_get_channel_name(ch->in_channel),
334  ch->input);
335  ret = AVERROR(EINVAL);
336  goto fail;
337  }
338 
339  inputs[ch->input] |= ch->in_channel;
340  }
341 
342  /* guess channel maps when not explicitly defined */
343  /* first try unused matching channels */
344  for (i = 0; i < s->nb_channels; i++) {
345  ChannelMap *ch = &s->channels[i];
346 
347  if (ch->input < 0)
348  guess_map_matching(ctx, ch, inputs);
349  }
350 
351  /* if the above failed, try to find _any_ unused input channel */
352  for (i = 0; i < s->nb_channels; i++) {
353  ChannelMap *ch = &s->channels[i];
354 
355  if (ch->input < 0)
356  guess_map_any(ctx, ch, inputs);
357 
358  if (ch->input < 0) {
359  av_log(ctx, AV_LOG_ERROR, "Could not find input channel for "
360  "output channel '%s'.\n",
362  goto fail;
363  }
364 
366  ch->in_channel);
367  }
368 
369  /* print mappings */
370  av_log(ctx, AV_LOG_VERBOSE, "mappings: ");
371  for (i = 0; i < s->nb_channels; i++) {
372  ChannelMap *ch = &s->channels[i];
373  av_log(ctx, AV_LOG_VERBOSE, "%d.%s => %s ", ch->input,
376  }
377  av_log(ctx, AV_LOG_VERBOSE, "\n");
378 
379  for (i = 0; i < ctx->nb_inputs; i++) {
380  if (!inputs[i])
381  av_log(ctx, AV_LOG_WARNING, "No channels are used from input "
382  "stream %d.\n", i);
383  }
384 
385 fail:
386  av_freep(&inputs);
387  return ret;
388 }
389 
390 static int join_request_frame(AVFilterLink *outlink)
391 {
392  AVFilterContext *ctx = outlink->src;
393  JoinContext *s = ctx->priv;
394  AVFrame *frame;
395  int linesize = INT_MAX;
396  int nb_samples = 0;
397  int nb_buffers = 0;
398  int i, j, ret;
399 
400  /* get a frame on each input */
401  for (i = 0; i < ctx->nb_inputs; i++) {
402  AVFilterLink *inlink = ctx->inputs[i];
403 
404  if (!s->input_frames[i] &&
405  (ret = ff_request_frame(inlink)) < 0)
406  return ret;
407 
408  /* request the same number of samples on all inputs */
409  if (i == 0) {
410  nb_samples = s->input_frames[0]->nb_samples;
411 
412  for (j = 1; !i && j < ctx->nb_inputs; j++)
413  ctx->inputs[j]->request_samples = nb_samples;
414  }
415  }
416 
417  /* setup the output frame */
418  frame = av_frame_alloc();
419  if (!frame)
420  return AVERROR(ENOMEM);
421  if (s->nb_channels > FF_ARRAY_ELEMS(frame->data)) {
422  frame->extended_data = av_mallocz(s->nb_channels *
423  sizeof(*frame->extended_data));
424  if (!frame->extended_data) {
425  ret = AVERROR(ENOMEM);
426  goto fail;
427  }
428  }
429 
430  /* copy the data pointers */
431  for (i = 0; i < s->nb_channels; i++) {
432  ChannelMap *ch = &s->channels[i];
433  AVFrame *cur = s->input_frames[ch->input];
434  AVBufferRef *buf;
435 
436  frame->extended_data[i] = cur->extended_data[ch->in_channel_idx];
437  linesize = FFMIN(linesize, cur->linesize[0]);
438 
439  /* add the buffer where this plan is stored to the list if it's
440  * not already there */
442  if (!buf) {
443  ret = AVERROR(EINVAL);
444  goto fail;
445  }
446  for (j = 0; j < nb_buffers; j++)
447  if (s->buffers[j]->buffer == buf->buffer)
448  break;
449  if (j == i)
450  s->buffers[nb_buffers++] = buf;
451  }
452 
453  /* create references to the buffers we copied to output */
454  if (nb_buffers > FF_ARRAY_ELEMS(frame->buf)) {
455  frame->nb_extended_buf = nb_buffers - FF_ARRAY_ELEMS(frame->buf);
456  frame->extended_buf = av_mallocz(sizeof(*frame->extended_buf) *
457  frame->nb_extended_buf);
458  if (!frame->extended_buf) {
459  frame->nb_extended_buf = 0;
460  ret = AVERROR(ENOMEM);
461  goto fail;
462  }
463  }
464  for (i = 0; i < FFMIN(FF_ARRAY_ELEMS(frame->buf), nb_buffers); i++) {
465  frame->buf[i] = av_buffer_ref(s->buffers[i]);
466  if (!frame->buf[i]) {
467  ret = AVERROR(ENOMEM);
468  goto fail;
469  }
470  }
471  for (i = 0; i < frame->nb_extended_buf; i++) {
472  frame->extended_buf[i] = av_buffer_ref(s->buffers[i +
473  FF_ARRAY_ELEMS(frame->buf)]);
474  if (!frame->extended_buf[i]) {
475  ret = AVERROR(ENOMEM);
476  goto fail;
477  }
478  }
479 
480  frame->nb_samples = nb_samples;
481  frame->channel_layout = outlink->channel_layout;
482  frame->sample_rate = outlink->sample_rate;
483  frame->pts = s->input_frames[0]->pts;
484  frame->linesize[0] = linesize;
485  if (frame->data != frame->extended_data) {
486  memcpy(frame->data, frame->extended_data, sizeof(*frame->data) *
487  FFMIN(FF_ARRAY_ELEMS(frame->data), s->nb_channels));
488  }
489 
490  ret = ff_filter_frame(outlink, frame);
491 
492  for (i = 0; i < ctx->nb_inputs; i++)
493  av_frame_free(&s->input_frames[i]);
494 
495  return ret;
496 
497 fail:
498  av_frame_free(&frame);
499  return ret;
500 }
501 
503  {
504  .name = "default",
505  .type = AVMEDIA_TYPE_AUDIO,
506  .config_props = join_config_output,
507  .request_frame = join_request_frame,
508  },
509  { NULL }
510 };
511 
513  .name = "join",
514  .description = NULL_IF_CONFIG_SMALL("Join multiple audio streams into "
515  "multi-channel output"),
516  .priv_size = sizeof(JoinContext),
517  .priv_class = &join_class,
518 
519  .init = join_init,
520  .uninit = join_uninit,
522 
523  .inputs = NULL,
524  .outputs = avfilter_af_join_outputs,
525 
527 };