avfilter.c
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1 /*
2  * filter layer
3  * Copyright (c) 2007 Bobby Bingham
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /* #define DEBUG */
23 
24 #include "libavutil/pixdesc.h"
25 #include "libavutil/rational.h"
26 #include "libavutil/audioconvert.h"
27 #include "libavutil/imgutils.h"
28 #include "libavcodec/avcodec.h"
29 #include "avfilter.h"
30 #include "internal.h"
31 
32 unsigned avfilter_version(void) {
34 }
35 
36 const char *avfilter_configuration(void)
37 {
38  return LIBAV_CONFIGURATION;
39 }
40 
41 const char *avfilter_license(void)
42 {
43 #define LICENSE_PREFIX "libavfilter license: "
44  return LICENSE_PREFIX LIBAV_LICENSE + sizeof(LICENSE_PREFIX) - 1;
45 }
46 
48 {
50  if (!ret)
51  return NULL;
52  *ret = *ref;
53  if (ref->type == AVMEDIA_TYPE_VIDEO) {
55  if (!ret->video) {
56  av_free(ret);
57  return NULL;
58  }
59  *ret->video = *ref->video;
60  } else if (ref->type == AVMEDIA_TYPE_AUDIO) {
62  if (!ret->audio) {
63  av_free(ret);
64  return NULL;
65  }
66  *ret->audio = *ref->audio;
67  }
68  ret->perms &= pmask;
69  ret->buf->refcount ++;
70  return ret;
71 }
72 
74 {
75  if (!ref)
76  return;
77  if (!(--ref->buf->refcount))
78  ref->buf->free(ref->buf);
79  av_free(ref->video);
80  av_free(ref->audio);
81  av_free(ref);
82 }
83 
84 void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
85  AVFilterPad **pads, AVFilterLink ***links,
86  AVFilterPad *newpad)
87 {
88  unsigned i;
89 
90  idx = FFMIN(idx, *count);
91 
92  *pads = av_realloc(*pads, sizeof(AVFilterPad) * (*count + 1));
93  *links = av_realloc(*links, sizeof(AVFilterLink*) * (*count + 1));
94  memmove(*pads +idx+1, *pads +idx, sizeof(AVFilterPad) * (*count-idx));
95  memmove(*links+idx+1, *links+idx, sizeof(AVFilterLink*) * (*count-idx));
96  memcpy(*pads+idx, newpad, sizeof(AVFilterPad));
97  (*links)[idx] = NULL;
98 
99  (*count)++;
100  for (i = idx+1; i < *count; i++)
101  if (*links[i])
102  (*(unsigned *)((uint8_t *) *links[i] + padidx_off))++;
103 }
104 
105 int avfilter_link(AVFilterContext *src, unsigned srcpad,
106  AVFilterContext *dst, unsigned dstpad)
107 {
108  AVFilterLink *link;
109 
110  if (src->output_count <= srcpad || dst->input_count <= dstpad ||
111  src->outputs[srcpad] || dst->inputs[dstpad])
112  return -1;
113 
114  if (src->output_pads[srcpad].type != dst->input_pads[dstpad].type) {
115  av_log(src, AV_LOG_ERROR,
116  "Media type mismatch between the '%s' filter output pad %d and the '%s' filter input pad %d\n",
117  src->name, srcpad, dst->name, dstpad);
118  return AVERROR(EINVAL);
119  }
120 
121  src->outputs[srcpad] =
122  dst-> inputs[dstpad] = link = av_mallocz(sizeof(AVFilterLink));
123 
124  link->src = src;
125  link->dst = dst;
126  link->srcpad = &src->output_pads[srcpad];
127  link->dstpad = &dst->input_pads[dstpad];
128  link->type = src->output_pads[srcpad].type;
129  assert(PIX_FMT_NONE == -1 && AV_SAMPLE_FMT_NONE == -1);
130  link->format = -1;
131 
132  return 0;
133 }
134 
136  unsigned filt_srcpad_idx, unsigned filt_dstpad_idx)
137 {
138  int ret;
139  unsigned dstpad_idx = link->dstpad - link->dst->input_pads;
140 
141  av_log(link->dst, AV_LOG_INFO, "auto-inserting filter '%s' "
142  "between the filter '%s' and the filter '%s'\n",
143  filt->name, link->src->name, link->dst->name);
144 
145  link->dst->inputs[dstpad_idx] = NULL;
146  if ((ret = avfilter_link(filt, filt_dstpad_idx, link->dst, dstpad_idx)) < 0) {
147  /* failed to link output filter to new filter */
148  link->dst->inputs[dstpad_idx] = link;
149  return ret;
150  }
151 
152  /* re-hookup the link to the new destination filter we inserted */
153  link->dst = filt;
154  link->dstpad = &filt->input_pads[filt_srcpad_idx];
155  filt->inputs[filt_srcpad_idx] = link;
156 
157  /* if any information on supported media formats already exists on the
158  * link, we need to preserve that */
159  if (link->out_formats)
161  &filt->outputs[filt_dstpad_idx]->out_formats);
162 
163  return 0;
164 }
165 
167 {
168  int (*config_link)(AVFilterLink *);
169  unsigned i;
170  int ret;
171 
172  for (i = 0; i < filter->input_count; i ++) {
173  AVFilterLink *link = filter->inputs[i];
174 
175  if (!link) continue;
176 
177  switch (link->init_state) {
178  case AVLINK_INIT:
179  continue;
180  case AVLINK_STARTINIT:
181  av_log(filter, AV_LOG_INFO, "circular filter chain detected\n");
182  return 0;
183  case AVLINK_UNINIT:
184  link->init_state = AVLINK_STARTINIT;
185 
186  if ((ret = avfilter_config_links(link->src)) < 0)
187  return ret;
188 
189  if (!(config_link = link->srcpad->config_props))
191  if ((ret = config_link(link)) < 0)
192  return ret;
193 
194  if (link->time_base.num == 0 && link->time_base.den == 0)
195  link->time_base = link->src && link->src->input_count ?
196  link->src->inputs[0]->time_base : AV_TIME_BASE_Q;
197 
198  if (link->sample_aspect_ratio.num == 0 && link->sample_aspect_ratio.den == 0)
199  link->sample_aspect_ratio = link->src->input_count ?
200  link->src->inputs[0]->sample_aspect_ratio : (AVRational){1,1};
201 
202  if (link->sample_rate == 0 && link->src && link->src->input_count)
203  link->sample_rate = link->src->inputs[0]->sample_rate;
204 
205  if (link->channel_layout == 0 && link->src && link->src->input_count)
206  link->channel_layout = link->src->inputs[0]->channel_layout;
207 
208  if ((config_link = link->dstpad->config_props))
209  if ((ret = config_link(link)) < 0)
210  return ret;
211 
212  link->init_state = AVLINK_INIT;
213  }
214  }
215 
216  return 0;
217 }
218 
219 #ifdef DEBUG
220 static char *ff_get_ref_perms_string(char *buf, size_t buf_size, int perms)
221 {
222  snprintf(buf, buf_size, "%s%s%s%s%s%s",
223  perms & AV_PERM_READ ? "r" : "",
224  perms & AV_PERM_WRITE ? "w" : "",
225  perms & AV_PERM_PRESERVE ? "p" : "",
226  perms & AV_PERM_REUSE ? "u" : "",
227  perms & AV_PERM_REUSE2 ? "U" : "",
228  perms & AV_PERM_NEG_LINESIZES ? "n" : "");
229  return buf;
230 }
231 #endif
232 
233 static void ff_dlog_ref(void *ctx, AVFilterBufferRef *ref, int end)
234 {
235  av_unused char buf[16];
236  av_dlog(ctx,
237  "ref[%p buf:%p refcount:%d perms:%s data:%p linesize[%d, %d, %d, %d] pts:%"PRId64" pos:%"PRId64,
238  ref, ref->buf, ref->buf->refcount, ff_get_ref_perms_string(buf, sizeof(buf), ref->perms), ref->data[0],
239  ref->linesize[0], ref->linesize[1], ref->linesize[2], ref->linesize[3],
240  ref->pts, ref->pos);
241 
242  if (ref->video) {
243  av_dlog(ctx, " a:%d/%d s:%dx%d i:%c iskey:%d type:%c",
245  ref->video->w, ref->video->h,
246  !ref->video->interlaced ? 'P' : /* Progressive */
247  ref->video->top_field_first ? 'T' : 'B', /* Top / Bottom */
248  ref->video->key_frame,
250  }
251  if (ref->audio) {
252  av_dlog(ctx, " cl:%"PRId64"d sn:%d s:%d sr:%d p:%d",
253  ref->audio->channel_layout,
254  ref->audio->nb_samples,
255  ref->audio->size,
256  ref->audio->sample_rate,
257  ref->audio->planar);
258  }
259 
260  av_dlog(ctx, "]%s", end ? "\n" : "");
261 }
262 
263 static void ff_dlog_link(void *ctx, AVFilterLink *link, int end)
264 {
265  if (link->type == AVMEDIA_TYPE_VIDEO) {
266  av_dlog(ctx,
267  "link[%p s:%dx%d fmt:%-16s %-16s->%-16s]%s",
268  link, link->w, link->h,
270  link->src ? link->src->filter->name : "",
271  link->dst ? link->dst->filter->name : "",
272  end ? "\n" : "");
273  } else {
274  char buf[128];
275  av_get_channel_layout_string(buf, sizeof(buf), -1, link->channel_layout);
276 
277  av_dlog(ctx,
278  "link[%p r:%"PRId64" cl:%s fmt:%-16s %-16s->%-16s]%s",
279  link, link->sample_rate, buf,
281  link->src ? link->src->filter->name : "",
282  link->dst ? link->dst->filter->name : "",
283  end ? "\n" : "");
284  }
285 }
286 
287 #define FF_DPRINTF_START(ctx, func) av_dlog(NULL, "%-16s: ", #func)
288 
290 {
291  AVFilterBufferRef *ret = NULL;
292 
293  av_unused char buf[16];
295  av_dlog(NULL, " perms:%s w:%d h:%d\n", ff_get_ref_perms_string(buf, sizeof(buf), perms), w, h);
296 
297  if (link->dstpad->get_video_buffer)
298  ret = link->dstpad->get_video_buffer(link, perms, w, h);
299 
300  if (!ret)
301  ret = avfilter_default_get_video_buffer(link, perms, w, h);
302 
303  if (ret)
304  ret->type = AVMEDIA_TYPE_VIDEO;
305 
306  FF_DPRINTF_START(NULL, get_video_buffer); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " returning "); ff_dlog_ref(NULL, ret, 1);
307 
308  return ret;
309 }
310 
312 avfilter_get_video_buffer_ref_from_arrays(uint8_t *data[4], int linesize[4], int perms,
313  int w, int h, enum PixelFormat format)
314 {
315  AVFilterBuffer *pic = av_mallocz(sizeof(AVFilterBuffer));
317 
318  if (!pic || !picref)
319  goto fail;
320 
321  picref->buf = pic;
323  if (!(picref->video = av_mallocz(sizeof(AVFilterBufferRefVideoProps))))
324  goto fail;
325 
326  pic->w = picref->video->w = w;
327  pic->h = picref->video->h = h;
328 
329  /* make sure the buffer gets read permission or it's useless for output */
330  picref->perms = perms | AV_PERM_READ;
331 
332  pic->refcount = 1;
333  picref->type = AVMEDIA_TYPE_VIDEO;
334  pic->format = picref->format = format;
335 
336  memcpy(pic->data, data, 4*sizeof(data[0]));
337  memcpy(pic->linesize, linesize, 4*sizeof(linesize[0]));
338  memcpy(picref->data, pic->data, sizeof(picref->data));
339  memcpy(picref->linesize, pic->linesize, sizeof(picref->linesize));
340 
341  return picref;
342 
343 fail:
344  if (picref && picref->video)
345  av_free(picref->video);
346  av_free(picref);
347  av_free(pic);
348  return NULL;
349 }
350 
352  enum AVSampleFormat sample_fmt, int size,
353  uint64_t channel_layout, int planar)
354 {
355  AVFilterBufferRef *ret = NULL;
356 
357  if (link->dstpad->get_audio_buffer)
358  ret = link->dstpad->get_audio_buffer(link, perms, sample_fmt, size, channel_layout, planar);
359 
360  if (!ret)
361  ret = avfilter_default_get_audio_buffer(link, perms, sample_fmt, size, channel_layout, planar);
362 
363  if (ret)
364  ret->type = AVMEDIA_TYPE_AUDIO;
365 
366  return ret;
367 }
368 
370 {
372 
373  if (link->srcpad->request_frame)
374  return link->srcpad->request_frame(link);
375  else if (link->src->inputs[0])
376  return avfilter_request_frame(link->src->inputs[0]);
377  else return -1;
378 }
379 
381 {
382  int i, min = INT_MAX;
383 
384  if (link->srcpad->poll_frame)
385  return link->srcpad->poll_frame(link);
386 
387  for (i = 0; i < link->src->input_count; i++) {
388  int val;
389  if (!link->src->inputs[i])
390  return -1;
391  val = avfilter_poll_frame(link->src->inputs[i]);
392  min = FFMIN(min, val);
393  }
394 
395  return min;
396 }
397 
398 /* XXX: should we do the duplicating of the picture ref here, instead of
399  * forcing the source filter to do it? */
401 {
403  AVFilterPad *dst = link->dstpad;
404  int perms = picref->perms;
405 
406  FF_DPRINTF_START(NULL, start_frame); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " "); ff_dlog_ref(NULL, picref, 1);
407 
408  if (!(start_frame = dst->start_frame))
410 
411  if (picref->linesize[0] < 0)
412  perms |= AV_PERM_NEG_LINESIZES;
413  /* prepare to copy the picture if it has insufficient permissions */
414  if ((dst->min_perms & perms) != dst->min_perms || dst->rej_perms & perms) {
415  av_log(link->dst, AV_LOG_DEBUG,
416  "frame copy needed (have perms %x, need %x, reject %x)\n",
417  picref->perms,
418  link->dstpad->min_perms, link->dstpad->rej_perms);
419 
420  link->cur_buf = avfilter_get_video_buffer(link, dst->min_perms, link->w, link->h);
421  link->src_buf = picref;
423  }
424  else
425  link->cur_buf = picref;
426 
427  start_frame(link, link->cur_buf);
428 }
429 
431 {
433 
434  if (!(end_frame = link->dstpad->end_frame))
436 
437  end_frame(link);
438 
439  /* unreference the source picture if we're feeding the destination filter
440  * a copied version dues to permission issues */
441  if (link->src_buf) {
443  link->src_buf = NULL;
444  }
445 }
446 
447 void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
448 {
449  uint8_t *src[4], *dst[4];
450  int i, j, vsub;
451  void (*draw_slice)(AVFilterLink *, int, int, int);
452 
453  FF_DPRINTF_START(NULL, draw_slice); ff_dlog_link(NULL, link, 0); av_dlog(NULL, " y:%d h:%d dir:%d\n", y, h, slice_dir);
454 
455  /* copy the slice if needed for permission reasons */
456  if (link->src_buf) {
458 
459  for (i = 0; i < 4; i++) {
460  if (link->src_buf->data[i]) {
461  src[i] = link->src_buf-> data[i] +
462  (y >> (i==1 || i==2 ? vsub : 0)) * link->src_buf-> linesize[i];
463  dst[i] = link->cur_buf->data[i] +
464  (y >> (i==1 || i==2 ? vsub : 0)) * link->cur_buf->linesize[i];
465  } else
466  src[i] = dst[i] = NULL;
467  }
468 
469  for (i = 0; i < 4; i++) {
470  int planew =
471  av_image_get_linesize(link->format, link->cur_buf->video->w, i);
472 
473  if (!src[i]) continue;
474 
475  for (j = 0; j < h >> (i==1 || i==2 ? vsub : 0); j++) {
476  memcpy(dst[i], src[i], planew);
477  src[i] += link->src_buf->linesize[i];
478  dst[i] += link->cur_buf->linesize[i];
479  }
480  }
481  }
482 
483  if (!(draw_slice = link->dstpad->draw_slice))
485  draw_slice(link, y, h, slice_dir);
486 }
487 
489 {
491  AVFilterPad *dst = link->dstpad;
492 
494 
495  if (!(filter_samples = dst->filter_samples))
497 
498  /* prepare to copy the samples if the buffer has insufficient permissions */
499  if ((dst->min_perms & samplesref->perms) != dst->min_perms ||
500  dst->rej_perms & samplesref->perms) {
501 
502  av_log(link->dst, AV_LOG_DEBUG,
503  "Copying audio data in avfilter (have perms %x, need %x, reject %x)\n",
504  samplesref->perms, link->dstpad->min_perms, link->dstpad->rej_perms);
505 
507  samplesref->format,
508  samplesref->audio->size,
509  samplesref->audio->channel_layout,
510  samplesref->audio->planar);
511  link->cur_buf->pts = samplesref->pts;
512  link->cur_buf->audio->sample_rate = samplesref->audio->sample_rate;
513 
514  /* Copy actual data into new samples buffer */
515  memcpy(link->cur_buf->data[0], samplesref->data[0], samplesref->audio->size);
516 
517  avfilter_unref_buffer(samplesref);
518  } else
519  link->cur_buf = samplesref;
520 
521  filter_samples(link, link->cur_buf);
522 }
523 
524 #define MAX_REGISTERED_AVFILTERS_NB 64
525 
527 
529 
531 {
532  int i;
533 
534  for (i = 0; registered_avfilters[i]; i++)
535  if (!strcmp(registered_avfilters[i]->name, name))
536  return registered_avfilters[i];
537 
538  return NULL;
539 }
540 
542 {
544  return -1;
545 
546  registered_avfilters[next_registered_avfilter_idx++] = filter;
547  return 0;
548 }
549 
551 {
552  return filter ? ++filter : &registered_avfilters[0];
553 }
554 
555 void avfilter_uninit(void)
556 {
557  memset(registered_avfilters, 0, sizeof(registered_avfilters));
559 }
560 
561 static int pad_count(const AVFilterPad *pads)
562 {
563  int count;
564 
565  for(count = 0; pads->name; count ++) pads ++;
566  return count;
567 }
568 
569 static const char *filter_name(void *p)
570 {
571  AVFilterContext *filter = p;
572  return filter->filter->name;
573 }
574 
575 static const AVClass avfilter_class = {
576  "AVFilter",
577  filter_name,
578  NULL,
580 };
581 
582 int avfilter_open(AVFilterContext **filter_ctx, AVFilter *filter, const char *inst_name)
583 {
584  AVFilterContext *ret;
585  *filter_ctx = NULL;
586 
587  if (!filter)
588  return AVERROR(EINVAL);
589 
590  ret = av_mallocz(sizeof(AVFilterContext));
591  if (!ret)
592  return AVERROR(ENOMEM);
593 
594  ret->av_class = &avfilter_class;
595  ret->filter = filter;
596  ret->name = inst_name ? av_strdup(inst_name) : NULL;
597  if (filter->priv_size) {
598  ret->priv = av_mallocz(filter->priv_size);
599  if (!ret->priv)
600  goto err;
601  }
602 
603  ret->input_count = pad_count(filter->inputs);
604  if (ret->input_count) {
605  ret->input_pads = av_malloc(sizeof(AVFilterPad) * ret->input_count);
606  if (!ret->input_pads)
607  goto err;
608  memcpy(ret->input_pads, filter->inputs, sizeof(AVFilterPad) * ret->input_count);
609  ret->inputs = av_mallocz(sizeof(AVFilterLink*) * ret->input_count);
610  if (!ret->inputs)
611  goto err;
612  }
613 
614  ret->output_count = pad_count(filter->outputs);
615  if (ret->output_count) {
616  ret->output_pads = av_malloc(sizeof(AVFilterPad) * ret->output_count);
617  if (!ret->output_pads)
618  goto err;
619  memcpy(ret->output_pads, filter->outputs, sizeof(AVFilterPad) * ret->output_count);
620  ret->outputs = av_mallocz(sizeof(AVFilterLink*) * ret->output_count);
621  if (!ret->outputs)
622  goto err;
623  }
624 
625  *filter_ctx = ret;
626  return 0;
627 
628 err:
629  av_freep(&ret->inputs);
630  av_freep(&ret->input_pads);
631  ret->input_count = 0;
632  av_freep(&ret->outputs);
633  av_freep(&ret->output_pads);
634  ret->output_count = 0;
635  av_freep(&ret->priv);
636  av_free(ret);
637  return AVERROR(ENOMEM);
638 }
639 
641 {
642  int i;
643  AVFilterLink *link;
644 
645  if (filter->filter->uninit)
646  filter->filter->uninit(filter);
647 
648  for (i = 0; i < filter->input_count; i++) {
649  if ((link = filter->inputs[i])) {
650  if (link->src)
651  link->src->outputs[link->srcpad - link->src->output_pads] = NULL;
654  }
655  av_freep(&link);
656  }
657  for (i = 0; i < filter->output_count; i++) {
658  if ((link = filter->outputs[i])) {
659  if (link->dst)
660  link->dst->inputs[link->dstpad - link->dst->input_pads] = NULL;
663  }
664  av_freep(&link);
665  }
666 
667  av_freep(&filter->name);
668  av_freep(&filter->input_pads);
669  av_freep(&filter->output_pads);
670  av_freep(&filter->inputs);
671  av_freep(&filter->outputs);
672  av_freep(&filter->priv);
673  av_free(filter);
674 }
675 
676 int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque)
677 {
678  int ret=0;
679 
680  if (filter->filter->init)
681  ret = filter->filter->init(filter, args, opaque);
682  return ret;
683 }
684 
686 {
687  if (dst->type != AVMEDIA_TYPE_VIDEO)
688  return AVERROR(EINVAL);
689 
690  dst->pts = src->pts;
691  dst->format = src->format;
692 
693  dst->video->w = src->width;
694  dst->video->h = src->height;
696  dst->video->interlaced = src->interlaced_frame;
698  dst->video->key_frame = src->key_frame;
699  dst->video->pict_type = src->pict_type;
700 
701  return 0;
702 }