avfiltergraph: Properly handle memory allocation failure
[ffmpeg.git] / libavfilter / avfiltergraph.c
1 /*
2  * filter graphs
3  * Copyright (c) 2008 Vitor Sessak
4  * Copyright (c) 2007 Bobby Bingham
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22
23 #include "config.h"
24
25 #include <string.h>
26
27 #include "libavutil/avassert.h"
28 #include "libavutil/avstring.h"
29 #include "libavutil/bprint.h"
30 #include "libavutil/channel_layout.h"
31 #include "libavutil/internal.h"
32 #include "libavutil/opt.h"
33 #include "libavutil/pixdesc.h"
34 #include "libavcodec/avcodec.h" // avcodec_find_best_pix_fmt_of_2()
35
36 #include "avfilter.h"
37 #include "formats.h"
38 #include "internal.h"
39 #include "thread.h"
40
41 #define OFFSET(x) offsetof(AVFilterGraph, x)
42 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
43 static const AVOption filtergraph_options[] = {
44     { "thread_type", "Allowed thread types", OFFSET(thread_type), AV_OPT_TYPE_FLAGS,
45         { .i64 = AVFILTER_THREAD_SLICE }, 0, INT_MAX, FLAGS, "thread_type" },
46         { "slice", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AVFILTER_THREAD_SLICE }, .flags = FLAGS, .unit = "thread_type" },
47     { "threads",     "Maximum number of threads", OFFSET(nb_threads),
48         AV_OPT_TYPE_INT,   { .i64 = 0 }, 0, INT_MAX, FLAGS },
49     {"scale_sws_opts"       , "default scale filter options"        , OFFSET(scale_sws_opts)        ,
50         AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
51     {"aresample_swr_opts"   , "default aresample filter options"    , OFFSET(aresample_swr_opts)    ,
52         AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
53     { NULL },
54 };
55
56 static const AVClass filtergraph_class = {
57     .class_name = "AVFilterGraph",
58     .item_name  = av_default_item_name,
59     .version    = LIBAVUTIL_VERSION_INT,
60     .option     = filtergraph_options,
61     .category   = AV_CLASS_CATEGORY_FILTER,
62 };
63
64 #if !HAVE_THREADS
65 void ff_graph_thread_free(AVFilterGraph *graph)
66 {
67 }
68
69 int ff_graph_thread_init(AVFilterGraph *graph)
70 {
71     graph->thread_type = 0;
72     graph->nb_threads  = 1;
73     return 0;
74 }
75 #endif
76
77 AVFilterGraph *avfilter_graph_alloc(void)
78 {
79     AVFilterGraph *ret = av_mallocz(sizeof(*ret));
80     if (!ret)
81         return NULL;
82
83     ret->internal = av_mallocz(sizeof(*ret->internal));
84     if (!ret->internal) {
85         av_freep(&ret);
86         return NULL;
87     }
88
89     ret->av_class = &filtergraph_class;
90     av_opt_set_defaults(ret);
91
92     return ret;
93 }
94
95 void ff_filter_graph_remove_filter(AVFilterGraph *graph, AVFilterContext *filter)
96 {
97     int i;
98     for (i = 0; i < graph->nb_filters; i++) {
99         if (graph->filters[i] == filter) {
100             FFSWAP(AVFilterContext*, graph->filters[i],
101                    graph->filters[graph->nb_filters - 1]);
102             graph->nb_filters--;
103             return;
104         }
105     }
106 }
107
108 void avfilter_graph_free(AVFilterGraph **graph)
109 {
110     if (!*graph)
111         return;
112
113     while ((*graph)->nb_filters)
114         avfilter_free((*graph)->filters[0]);
115
116     ff_graph_thread_free(*graph);
117
118     av_freep(&(*graph)->sink_links);
119
120     av_freep(&(*graph)->scale_sws_opts);
121     av_freep(&(*graph)->aresample_swr_opts);
122     av_freep(&(*graph)->resample_lavr_opts);
123     av_freep(&(*graph)->filters);
124     av_freep(&(*graph)->internal);
125     av_freep(graph);
126 }
127
128 #if FF_API_AVFILTER_OPEN
129 int avfilter_graph_add_filter(AVFilterGraph *graph, AVFilterContext *filter)
130 {
131     AVFilterContext **filters = av_realloc(graph->filters,
132                                            sizeof(*filters) * (graph->nb_filters + 1));
133     if (!filters)
134         return AVERROR(ENOMEM);
135
136     graph->filters = filters;
137     graph->filters[graph->nb_filters++] = filter;
138
139 #if FF_API_FOO_COUNT
140 FF_DISABLE_DEPRECATION_WARNINGS
141     graph->filter_count_unused = graph->nb_filters;
142 FF_ENABLE_DEPRECATION_WARNINGS
143 #endif
144
145     filter->graph = graph;
146
147     return 0;
148 }
149 #endif
150
151 int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt,
152                                  const char *name, const char *args, void *opaque,
153                                  AVFilterGraph *graph_ctx)
154 {
155     int ret;
156
157     *filt_ctx = avfilter_graph_alloc_filter(graph_ctx, filt, name);
158     if (!*filt_ctx)
159         return AVERROR(ENOMEM);
160
161     ret = avfilter_init_str(*filt_ctx, args);
162     if (ret < 0)
163         goto fail;
164
165     return 0;
166
167 fail:
168     if (*filt_ctx)
169         avfilter_free(*filt_ctx);
170     *filt_ctx = NULL;
171     return ret;
172 }
173
174 void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags)
175 {
176     graph->disable_auto_convert = flags;
177 }
178
179 AVFilterContext *avfilter_graph_alloc_filter(AVFilterGraph *graph,
180                                              const AVFilter *filter,
181                                              const char *name)
182 {
183     AVFilterContext **filters, *s;
184
185     if (graph->thread_type && !graph->internal->thread_execute) {
186         if (graph->execute) {
187             graph->internal->thread_execute = graph->execute;
188         } else {
189             int ret = ff_graph_thread_init(graph);
190             if (ret < 0) {
191                 av_log(graph, AV_LOG_ERROR, "Error initializing threading.\n");
192                 return NULL;
193             }
194         }
195     }
196
197     s = ff_filter_alloc(filter, name);
198     if (!s)
199         return NULL;
200
201     filters = av_realloc(graph->filters, sizeof(*filters) * (graph->nb_filters + 1));
202     if (!filters) {
203         avfilter_free(s);
204         return NULL;
205     }
206
207     graph->filters = filters;
208     graph->filters[graph->nb_filters++] = s;
209
210 #if FF_API_FOO_COUNT
211 FF_DISABLE_DEPRECATION_WARNINGS
212     graph->filter_count_unused = graph->nb_filters;
213 FF_ENABLE_DEPRECATION_WARNINGS
214 #endif
215
216     s->graph = graph;
217
218     return s;
219 }
220
221 /**
222  * Check for the validity of graph.
223  *
224  * A graph is considered valid if all its input and output pads are
225  * connected.
226  *
227  * @return >= 0 in case of success, a negative value otherwise
228  */
229 static int graph_check_validity(AVFilterGraph *graph, AVClass *log_ctx)
230 {
231     AVFilterContext *filt;
232     int i, j;
233
234     for (i = 0; i < graph->nb_filters; i++) {
235         const AVFilterPad *pad;
236         filt = graph->filters[i];
237
238         for (j = 0; j < filt->nb_inputs; j++) {
239             if (!filt->inputs[j] || !filt->inputs[j]->src) {
240                 pad = &filt->input_pads[j];
241                 av_log(log_ctx, AV_LOG_ERROR,
242                        "Input pad \"%s\" with type %s of the filter instance \"%s\" of %s not connected to any source\n",
243                        pad->name, av_get_media_type_string(pad->type), filt->name, filt->filter->name);
244                 return AVERROR(EINVAL);
245             }
246         }
247
248         for (j = 0; j < filt->nb_outputs; j++) {
249             if (!filt->outputs[j] || !filt->outputs[j]->dst) {
250                 pad = &filt->output_pads[j];
251                 av_log(log_ctx, AV_LOG_ERROR,
252                        "Output pad \"%s\" with type %s of the filter instance \"%s\" of %s not connected to any destination\n",
253                        pad->name, av_get_media_type_string(pad->type), filt->name, filt->filter->name);
254                 return AVERROR(EINVAL);
255             }
256         }
257     }
258
259     return 0;
260 }
261
262 /**
263  * Configure all the links of graphctx.
264  *
265  * @return >= 0 in case of success, a negative value otherwise
266  */
267 static int graph_config_links(AVFilterGraph *graph, AVClass *log_ctx)
268 {
269     AVFilterContext *filt;
270     int i, ret;
271
272     for (i = 0; i < graph->nb_filters; i++) {
273         filt = graph->filters[i];
274
275         if (!filt->nb_outputs) {
276             if ((ret = avfilter_config_links(filt)))
277                 return ret;
278         }
279     }
280
281     return 0;
282 }
283
284 AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name)
285 {
286     int i;
287
288     for (i = 0; i < graph->nb_filters; i++)
289         if (graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
290             return graph->filters[i];
291
292     return NULL;
293 }
294
295 static void sanitize_channel_layouts(void *log, AVFilterChannelLayouts *l)
296 {
297     if (!l)
298         return;
299     if (l->nb_channel_layouts) {
300         if (l->all_layouts || l->all_counts)
301             av_log(log, AV_LOG_WARNING, "All layouts set on non-empty list\n");
302         l->all_layouts = l->all_counts = 0;
303     } else {
304         if (l->all_counts && !l->all_layouts)
305             av_log(log, AV_LOG_WARNING, "All counts without all layouts\n");
306         l->all_layouts = 1;
307     }
308 }
309
310 static int filter_query_formats(AVFilterContext *ctx)
311 {
312     int ret, i;
313     AVFilterFormats *formats;
314     AVFilterChannelLayouts *chlayouts;
315     AVFilterFormats *samplerates;
316     enum AVMediaType type = ctx->inputs  && ctx->inputs [0] ? ctx->inputs [0]->type :
317                             ctx->outputs && ctx->outputs[0] ? ctx->outputs[0]->type :
318                             AVMEDIA_TYPE_VIDEO;
319
320     if ((ret = ctx->filter->query_formats(ctx)) < 0) {
321         if (ret != AVERROR(EAGAIN))
322             av_log(ctx, AV_LOG_ERROR, "Query format failed for '%s': %s\n",
323                    ctx->name, av_err2str(ret));
324         return ret;
325     }
326
327     for (i = 0; i < ctx->nb_inputs; i++)
328         sanitize_channel_layouts(ctx, ctx->inputs[i]->out_channel_layouts);
329     for (i = 0; i < ctx->nb_outputs; i++)
330         sanitize_channel_layouts(ctx, ctx->outputs[i]->in_channel_layouts);
331
332     formats = ff_all_formats(type);
333     if (!formats)
334         return AVERROR(ENOMEM);
335     ff_set_common_formats(ctx, formats);
336     if (type == AVMEDIA_TYPE_AUDIO) {
337         samplerates = ff_all_samplerates();
338         if (!samplerates)
339             return AVERROR(ENOMEM);
340         ff_set_common_samplerates(ctx, samplerates);
341         chlayouts = ff_all_channel_layouts();
342         if (!chlayouts)
343             return AVERROR(ENOMEM);
344         ff_set_common_channel_layouts(ctx, chlayouts);
345     }
346     return 0;
347 }
348
349 static int formats_declared(AVFilterContext *f)
350 {
351     int i;
352
353     for (i = 0; i < f->nb_inputs; i++) {
354         if (!f->inputs[i]->out_formats)
355             return 0;
356         if (f->inputs[i]->type == AVMEDIA_TYPE_AUDIO &&
357             !(f->inputs[i]->out_samplerates &&
358               f->inputs[i]->out_channel_layouts))
359             return 0;
360     }
361     for (i = 0; i < f->nb_outputs; i++) {
362         if (!f->outputs[i]->in_formats)
363             return 0;
364         if (f->outputs[i]->type == AVMEDIA_TYPE_AUDIO &&
365             !(f->outputs[i]->in_samplerates &&
366               f->outputs[i]->in_channel_layouts))
367             return 0;
368     }
369     return 1;
370 }
371
372 static AVFilterFormats *clone_filter_formats(AVFilterFormats *arg)
373 {
374     AVFilterFormats *a = av_memdup(arg, sizeof(*arg));
375     if (a) {
376         a->refcount = 0;
377         a->refs     = NULL;
378         a->formats  = av_memdup(a->formats, sizeof(*a->formats) * a->nb_formats);
379         if (!a->formats && arg->formats)
380             av_freep(&a);
381     }
382     return a;
383 }
384
385 static int can_merge_formats(AVFilterFormats *a_arg,
386                              AVFilterFormats *b_arg,
387                              enum AVMediaType type,
388                              int is_sample_rate)
389 {
390     AVFilterFormats *a, *b, *ret;
391     if (a_arg == b_arg)
392         return 1;
393     a = clone_filter_formats(a_arg);
394     b = clone_filter_formats(b_arg);
395
396     if (!a || !b) {
397         if (a)
398             av_freep(&a->formats);
399         if (b)
400             av_freep(&b->formats);
401
402         av_freep(&a);
403         av_freep(&b);
404
405         return 0;
406     }
407
408     if (is_sample_rate) {
409         ret = ff_merge_samplerates(a, b);
410     } else {
411         ret = ff_merge_formats(a, b, type);
412     }
413     if (ret) {
414         av_freep(&ret->formats);
415         av_freep(&ret->refs);
416         av_freep(&ret);
417         return 1;
418     } else {
419         av_freep(&a->formats);
420         av_freep(&b->formats);
421         av_freep(&a);
422         av_freep(&b);
423         return 0;
424     }
425 }
426
427 /**
428  * Perform one round of query_formats() and merging formats lists on the
429  * filter graph.
430  * @return  >=0 if all links formats lists could be queried and merged;
431  *          AVERROR(EAGAIN) some progress was made in the queries or merging
432  *          and a later call may succeed;
433  *          AVERROR(EIO) (may be changed) plus a log message if no progress
434  *          was made and the negotiation is stuck;
435  *          a negative error code if some other error happened
436  */
437 static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
438 {
439     int i, j, ret;
440     int scaler_count = 0, resampler_count = 0;
441     int count_queried = 0;        /* successful calls to query_formats() */
442     int count_merged = 0;         /* successful merge of formats lists */
443     int count_already_merged = 0; /* lists already merged */
444     int count_delayed = 0;        /* lists that need to be merged later */
445
446     for (i = 0; i < graph->nb_filters; i++) {
447         AVFilterContext *f = graph->filters[i];
448         if (formats_declared(f))
449             continue;
450         if (f->filter->query_formats)
451             ret = filter_query_formats(f);
452         else
453             ret = ff_default_query_formats(f);
454         if (ret < 0 && ret != AVERROR(EAGAIN))
455             return ret;
456         /* note: EAGAIN could indicate a partial success, not counted yet */
457         count_queried += ret >= 0;
458     }
459
460     /* go through and merge as many format lists as possible */
461     for (i = 0; i < graph->nb_filters; i++) {
462         AVFilterContext *filter = graph->filters[i];
463
464         for (j = 0; j < filter->nb_inputs; j++) {
465             AVFilterLink *link = filter->inputs[j];
466             int convert_needed = 0;
467
468             if (!link)
469                 continue;
470
471             if (link->in_formats != link->out_formats
472                 && link->in_formats && link->out_formats)
473                 if (!can_merge_formats(link->in_formats, link->out_formats,
474                                       link->type, 0))
475                     convert_needed = 1;
476             if (link->type == AVMEDIA_TYPE_AUDIO) {
477                 if (link->in_samplerates != link->out_samplerates
478                     && link->in_samplerates && link->out_samplerates)
479                     if (!can_merge_formats(link->in_samplerates,
480                                            link->out_samplerates,
481                                            0, 1))
482                         convert_needed = 1;
483             }
484
485 #define MERGE_DISPATCH(field, statement)                                     \
486             if (!(link->in_ ## field && link->out_ ## field)) {              \
487                 count_delayed++;                                             \
488             } else if (link->in_ ## field == link->out_ ## field) {          \
489                 count_already_merged++;                                      \
490             } else if (!convert_needed) {                                    \
491                 count_merged++;                                              \
492                 statement                                                    \
493             }
494
495             if (link->type == AVMEDIA_TYPE_AUDIO) {
496                 MERGE_DISPATCH(channel_layouts,
497                     if (!ff_merge_channel_layouts(link->in_channel_layouts,
498                                                   link->out_channel_layouts))
499                         convert_needed = 1;
500                 )
501                 MERGE_DISPATCH(samplerates,
502                     if (!ff_merge_samplerates(link->in_samplerates,
503                                               link->out_samplerates))
504                         convert_needed = 1;
505                 )
506             }
507             MERGE_DISPATCH(formats,
508                 if (!ff_merge_formats(link->in_formats, link->out_formats,
509                                       link->type))
510                     convert_needed = 1;
511             )
512 #undef MERGE_DISPATCH
513
514             if (convert_needed) {
515                 AVFilterContext *convert;
516                 AVFilter *filter;
517                 AVFilterLink *inlink, *outlink;
518                 char scale_args[256];
519                 char inst_name[30];
520
521                 /* couldn't merge format lists. auto-insert conversion filter */
522                 switch (link->type) {
523                 case AVMEDIA_TYPE_VIDEO:
524                     if (!(filter = avfilter_get_by_name("scale"))) {
525                         av_log(log_ctx, AV_LOG_ERROR, "'scale' filter "
526                                "not present, cannot convert pixel formats.\n");
527                         return AVERROR(EINVAL);
528                     }
529
530                     snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d",
531                              scaler_count++);
532
533                     if ((ret = avfilter_graph_create_filter(&convert, filter,
534                                                             inst_name, graph->scale_sws_opts, NULL,
535                                                             graph)) < 0)
536                         return ret;
537                     break;
538                 case AVMEDIA_TYPE_AUDIO:
539                     if (!(filter = avfilter_get_by_name("aresample"))) {
540                         av_log(log_ctx, AV_LOG_ERROR, "'aresample' filter "
541                                "not present, cannot convert audio formats.\n");
542                         return AVERROR(EINVAL);
543                     }
544
545                     snprintf(inst_name, sizeof(inst_name), "auto-inserted resampler %d",
546                              resampler_count++);
547                     scale_args[0] = '\0';
548                     if (graph->aresample_swr_opts)
549                         snprintf(scale_args, sizeof(scale_args), "%s",
550                                  graph->aresample_swr_opts);
551                     if ((ret = avfilter_graph_create_filter(&convert, filter,
552                                                             inst_name, graph->aresample_swr_opts,
553                                                             NULL, graph)) < 0)
554                         return ret;
555                     break;
556                 default:
557                     return AVERROR(EINVAL);
558                 }
559
560                 if ((ret = avfilter_insert_filter(link, convert, 0, 0)) < 0)
561                     return ret;
562
563                 filter_query_formats(convert);
564                 inlink  = convert->inputs[0];
565                 outlink = convert->outputs[0];
566                 if (!ff_merge_formats( inlink->in_formats,  inlink->out_formats,  inlink->type) ||
567                     !ff_merge_formats(outlink->in_formats, outlink->out_formats, outlink->type))
568                     ret |= AVERROR(ENOSYS);
569                 if (inlink->type == AVMEDIA_TYPE_AUDIO &&
570                     (!ff_merge_samplerates(inlink->in_samplerates,
571                                            inlink->out_samplerates) ||
572                      !ff_merge_channel_layouts(inlink->in_channel_layouts,
573                                                inlink->out_channel_layouts)))
574                     ret |= AVERROR(ENOSYS);
575                 if (outlink->type == AVMEDIA_TYPE_AUDIO &&
576                     (!ff_merge_samplerates(outlink->in_samplerates,
577                                            outlink->out_samplerates) ||
578                      !ff_merge_channel_layouts(outlink->in_channel_layouts,
579                                                outlink->out_channel_layouts)))
580                     ret |= AVERROR(ENOSYS);
581
582                 if (ret < 0) {
583                     av_log(log_ctx, AV_LOG_ERROR,
584                            "Impossible to convert between the formats supported by the filter "
585                            "'%s' and the filter '%s'\n", link->src->name, link->dst->name);
586                     return ret;
587                 }
588             }
589         }
590     }
591
592     av_log(graph, AV_LOG_DEBUG, "query_formats: "
593            "%d queried, %d merged, %d already done, %d delayed\n",
594            count_queried, count_merged, count_already_merged, count_delayed);
595     if (count_delayed) {
596         AVBPrint bp;
597
598         /* if count_queried > 0, one filter at least did set its formats,
599            that will give additional information to its neighbour;
600            if count_merged > 0, one pair of formats lists at least was merged,
601            that will give additional information to all connected filters;
602            in both cases, progress was made and a new round must be done */
603         if (count_queried || count_merged)
604             return AVERROR(EAGAIN);
605         av_bprint_init(&bp, 0, AV_BPRINT_SIZE_AUTOMATIC);
606         for (i = 0; i < graph->nb_filters; i++)
607             if (!formats_declared(graph->filters[i]))
608                 av_bprintf(&bp, "%s%s", bp.len ? ", " : "",
609                           graph->filters[i]->name);
610         av_log(graph, AV_LOG_ERROR,
611                "The following filters could not choose their formats: %s\n"
612                "Consider inserting the (a)format filter near their input or "
613                "output.\n", bp.str);
614         return AVERROR(EIO);
615     }
616     return 0;
617 }
618
619 static int pick_format(AVFilterLink *link, AVFilterLink *ref)
620 {
621     if (!link || !link->in_formats)
622         return 0;
623
624     if (link->type == AVMEDIA_TYPE_VIDEO) {
625         if(ref && ref->type == AVMEDIA_TYPE_VIDEO){
626             int has_alpha= av_pix_fmt_desc_get(ref->format)->nb_components % 2 == 0;
627             enum AVPixelFormat best= AV_PIX_FMT_NONE;
628             int i;
629             for (i=0; i<link->in_formats->nb_formats; i++) {
630                 enum AVPixelFormat p = link->in_formats->formats[i];
631                 best= avcodec_find_best_pix_fmt_of_2(best, p, ref->format, has_alpha, NULL);
632             }
633             av_log(link->src,AV_LOG_DEBUG, "picking %s out of %d ref:%s alpha:%d\n",
634                    av_get_pix_fmt_name(best), link->in_formats->nb_formats,
635                    av_get_pix_fmt_name(ref->format), has_alpha);
636             link->in_formats->formats[0] = best;
637         }
638     }
639
640     link->in_formats->nb_formats = 1;
641     link->format = link->in_formats->formats[0];
642
643     if (link->type == AVMEDIA_TYPE_AUDIO) {
644         if (!link->in_samplerates->nb_formats) {
645             av_log(link->src, AV_LOG_ERROR, "Cannot select sample rate for"
646                    " the link between filters %s and %s.\n", link->src->name,
647                    link->dst->name);
648             return AVERROR(EINVAL);
649         }
650         link->in_samplerates->nb_formats = 1;
651         link->sample_rate = link->in_samplerates->formats[0];
652
653         if (link->in_channel_layouts->all_layouts) {
654             av_log(link->src, AV_LOG_ERROR, "Cannot select channel layout for"
655                    " the link between filters %s and %s.\n", link->src->name,
656                    link->dst->name);
657             return AVERROR(EINVAL);
658         }
659         link->in_channel_layouts->nb_channel_layouts = 1;
660         link->channel_layout = link->in_channel_layouts->channel_layouts[0];
661         if ((link->channels = FF_LAYOUT2COUNT(link->channel_layout)))
662             link->channel_layout = 0;
663         else
664             link->channels = av_get_channel_layout_nb_channels(link->channel_layout);
665     }
666
667     ff_formats_unref(&link->in_formats);
668     ff_formats_unref(&link->out_formats);
669     ff_formats_unref(&link->in_samplerates);
670     ff_formats_unref(&link->out_samplerates);
671     ff_channel_layouts_unref(&link->in_channel_layouts);
672     ff_channel_layouts_unref(&link->out_channel_layouts);
673
674     return 0;
675 }
676
677 #define REDUCE_FORMATS(fmt_type, list_type, list, var, nb, add_format) \
678 do {                                                                   \
679     for (i = 0; i < filter->nb_inputs; i++) {                          \
680         AVFilterLink *link = filter->inputs[i];                        \
681         fmt_type fmt;                                                  \
682                                                                        \
683         if (!link->out_ ## list || link->out_ ## list->nb != 1)        \
684             continue;                                                  \
685         fmt = link->out_ ## list->var[0];                              \
686                                                                        \
687         for (j = 0; j < filter->nb_outputs; j++) {                     \
688             AVFilterLink *out_link = filter->outputs[j];               \
689             list_type *fmts;                                           \
690                                                                        \
691             if (link->type != out_link->type ||                        \
692                 out_link->in_ ## list->nb == 1)                        \
693                 continue;                                              \
694             fmts = out_link->in_ ## list;                              \
695                                                                        \
696             if (!out_link->in_ ## list->nb) {                          \
697                 add_format(&out_link->in_ ##list, fmt);                \
698                 ret = 1;                                               \
699                 break;                                                 \
700             }                                                          \
701                                                                        \
702             for (k = 0; k < out_link->in_ ## list->nb; k++)            \
703                 if (fmts->var[k] == fmt) {                             \
704                     fmts->var[0]  = fmt;                               \
705                     fmts->nb = 1;                                      \
706                     ret = 1;                                           \
707                     break;                                             \
708                 }                                                      \
709         }                                                              \
710     }                                                                  \
711 } while (0)
712
713 static int reduce_formats_on_filter(AVFilterContext *filter)
714 {
715     int i, j, k, ret = 0;
716
717     REDUCE_FORMATS(int,      AVFilterFormats,        formats,         formats,
718                    nb_formats, ff_add_format);
719     REDUCE_FORMATS(int,      AVFilterFormats,        samplerates,     formats,
720                    nb_formats, ff_add_format);
721
722     /* reduce channel layouts */
723     for (i = 0; i < filter->nb_inputs; i++) {
724         AVFilterLink *inlink = filter->inputs[i];
725         uint64_t fmt;
726
727         if (!inlink->out_channel_layouts ||
728             inlink->out_channel_layouts->nb_channel_layouts != 1)
729             continue;
730         fmt = inlink->out_channel_layouts->channel_layouts[0];
731
732         for (j = 0; j < filter->nb_outputs; j++) {
733             AVFilterLink *outlink = filter->outputs[j];
734             AVFilterChannelLayouts *fmts;
735
736             fmts = outlink->in_channel_layouts;
737             if (inlink->type != outlink->type || fmts->nb_channel_layouts == 1)
738                 continue;
739
740             if (fmts->all_layouts) {
741                 /* Turn the infinite list into a singleton */
742                 fmts->all_layouts = fmts->all_counts  = 0;
743                 ff_add_channel_layout(&outlink->in_channel_layouts, fmt);
744                 break;
745             }
746
747             for (k = 0; k < outlink->in_channel_layouts->nb_channel_layouts; k++) {
748                 if (fmts->channel_layouts[k] == fmt) {
749                     fmts->channel_layouts[0]  = fmt;
750                     fmts->nb_channel_layouts = 1;
751                     ret = 1;
752                     break;
753                 }
754             }
755         }
756     }
757
758     return ret;
759 }
760
761 static void reduce_formats(AVFilterGraph *graph)
762 {
763     int i, reduced;
764
765     do {
766         reduced = 0;
767
768         for (i = 0; i < graph->nb_filters; i++)
769             reduced |= reduce_formats_on_filter(graph->filters[i]);
770     } while (reduced);
771 }
772
773 static void swap_samplerates_on_filter(AVFilterContext *filter)
774 {
775     AVFilterLink *link = NULL;
776     int sample_rate;
777     int i, j;
778
779     for (i = 0; i < filter->nb_inputs; i++) {
780         link = filter->inputs[i];
781
782         if (link->type == AVMEDIA_TYPE_AUDIO &&
783             link->out_samplerates->nb_formats== 1)
784             break;
785     }
786     if (i == filter->nb_inputs)
787         return;
788
789     sample_rate = link->out_samplerates->formats[0];
790
791     for (i = 0; i < filter->nb_outputs; i++) {
792         AVFilterLink *outlink = filter->outputs[i];
793         int best_idx, best_diff = INT_MAX;
794
795         if (outlink->type != AVMEDIA_TYPE_AUDIO ||
796             outlink->in_samplerates->nb_formats < 2)
797             continue;
798
799         for (j = 0; j < outlink->in_samplerates->nb_formats; j++) {
800             int diff = abs(sample_rate - outlink->in_samplerates->formats[j]);
801
802             if (diff < best_diff) {
803                 best_diff = diff;
804                 best_idx  = j;
805             }
806         }
807         FFSWAP(int, outlink->in_samplerates->formats[0],
808                outlink->in_samplerates->formats[best_idx]);
809     }
810 }
811
812 static void swap_samplerates(AVFilterGraph *graph)
813 {
814     int i;
815
816     for (i = 0; i < graph->nb_filters; i++)
817         swap_samplerates_on_filter(graph->filters[i]);
818 }
819
820 #define CH_CENTER_PAIR (AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER)
821 #define CH_FRONT_PAIR  (AV_CH_FRONT_LEFT           | AV_CH_FRONT_RIGHT)
822 #define CH_STEREO_PAIR (AV_CH_STEREO_LEFT          | AV_CH_STEREO_RIGHT)
823 #define CH_WIDE_PAIR   (AV_CH_WIDE_LEFT            | AV_CH_WIDE_RIGHT)
824 #define CH_SIDE_PAIR   (AV_CH_SIDE_LEFT            | AV_CH_SIDE_RIGHT)
825 #define CH_DIRECT_PAIR (AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT)
826 #define CH_BACK_PAIR   (AV_CH_BACK_LEFT            | AV_CH_BACK_RIGHT)
827
828 /* allowable substitutions for channel pairs when comparing layouts,
829  * ordered by priority for both values */
830 static const uint64_t ch_subst[][2] = {
831     { CH_FRONT_PAIR,      CH_CENTER_PAIR     },
832     { CH_FRONT_PAIR,      CH_WIDE_PAIR       },
833     { CH_FRONT_PAIR,      AV_CH_FRONT_CENTER },
834     { CH_CENTER_PAIR,     CH_FRONT_PAIR      },
835     { CH_CENTER_PAIR,     CH_WIDE_PAIR       },
836     { CH_CENTER_PAIR,     AV_CH_FRONT_CENTER },
837     { CH_WIDE_PAIR,       CH_FRONT_PAIR      },
838     { CH_WIDE_PAIR,       CH_CENTER_PAIR     },
839     { CH_WIDE_PAIR,       AV_CH_FRONT_CENTER },
840     { AV_CH_FRONT_CENTER, CH_FRONT_PAIR      },
841     { AV_CH_FRONT_CENTER, CH_CENTER_PAIR     },
842     { AV_CH_FRONT_CENTER, CH_WIDE_PAIR       },
843     { CH_SIDE_PAIR,       CH_DIRECT_PAIR     },
844     { CH_SIDE_PAIR,       CH_BACK_PAIR       },
845     { CH_SIDE_PAIR,       AV_CH_BACK_CENTER  },
846     { CH_BACK_PAIR,       CH_DIRECT_PAIR     },
847     { CH_BACK_PAIR,       CH_SIDE_PAIR       },
848     { CH_BACK_PAIR,       AV_CH_BACK_CENTER  },
849     { AV_CH_BACK_CENTER,  CH_BACK_PAIR       },
850     { AV_CH_BACK_CENTER,  CH_DIRECT_PAIR     },
851     { AV_CH_BACK_CENTER,  CH_SIDE_PAIR       },
852 };
853
854 static void swap_channel_layouts_on_filter(AVFilterContext *filter)
855 {
856     AVFilterLink *link = NULL;
857     int i, j, k;
858
859     for (i = 0; i < filter->nb_inputs; i++) {
860         link = filter->inputs[i];
861
862         if (link->type == AVMEDIA_TYPE_AUDIO &&
863             link->out_channel_layouts->nb_channel_layouts == 1)
864             break;
865     }
866     if (i == filter->nb_inputs)
867         return;
868
869     for (i = 0; i < filter->nb_outputs; i++) {
870         AVFilterLink *outlink = filter->outputs[i];
871         int best_idx = -1, best_score = INT_MIN, best_count_diff = INT_MAX;
872
873         if (outlink->type != AVMEDIA_TYPE_AUDIO ||
874             outlink->in_channel_layouts->nb_channel_layouts < 2)
875             continue;
876
877         for (j = 0; j < outlink->in_channel_layouts->nb_channel_layouts; j++) {
878             uint64_t  in_chlayout = link->out_channel_layouts->channel_layouts[0];
879             uint64_t out_chlayout = outlink->in_channel_layouts->channel_layouts[j];
880             int  in_channels      = av_get_channel_layout_nb_channels(in_chlayout);
881             int out_channels      = av_get_channel_layout_nb_channels(out_chlayout);
882             int count_diff        = out_channels - in_channels;
883             int matched_channels, extra_channels;
884             int score = 100000;
885
886             if (FF_LAYOUT2COUNT(in_chlayout) || FF_LAYOUT2COUNT(out_chlayout)) {
887                 /* Compute score in case the input or output layout encodes
888                    a channel count; in this case the score is not altered by
889                    the computation afterwards, as in_chlayout and
890                    out_chlayout have both been set to 0 */
891                 if (FF_LAYOUT2COUNT(in_chlayout))
892                     in_channels = FF_LAYOUT2COUNT(in_chlayout);
893                 if (FF_LAYOUT2COUNT(out_chlayout))
894                     out_channels = FF_LAYOUT2COUNT(out_chlayout);
895                 score -= 10000 + FFABS(out_channels - in_channels) +
896                          (in_channels > out_channels ? 10000 : 0);
897                 in_chlayout = out_chlayout = 0;
898                 /* Let the remaining computation run, even if the score
899                    value is not altered */
900             }
901
902             /* channel substitution */
903             for (k = 0; k < FF_ARRAY_ELEMS(ch_subst); k++) {
904                 uint64_t cmp0 = ch_subst[k][0];
905                 uint64_t cmp1 = ch_subst[k][1];
906                 if (( in_chlayout & cmp0) && (!(out_chlayout & cmp0)) &&
907                     (out_chlayout & cmp1) && (!( in_chlayout & cmp1))) {
908                     in_chlayout  &= ~cmp0;
909                     out_chlayout &= ~cmp1;
910                     /* add score for channel match, minus a deduction for
911                        having to do the substitution */
912                     score += 10 * av_get_channel_layout_nb_channels(cmp1) - 2;
913                 }
914             }
915
916             /* no penalty for LFE channel mismatch */
917             if ( (in_chlayout & AV_CH_LOW_FREQUENCY) &&
918                 (out_chlayout & AV_CH_LOW_FREQUENCY))
919                 score += 10;
920             in_chlayout  &= ~AV_CH_LOW_FREQUENCY;
921             out_chlayout &= ~AV_CH_LOW_FREQUENCY;
922
923             matched_channels = av_get_channel_layout_nb_channels(in_chlayout &
924                                                                  out_chlayout);
925             extra_channels   = av_get_channel_layout_nb_channels(out_chlayout &
926                                                                  (~in_chlayout));
927             score += 10 * matched_channels - 5 * extra_channels;
928
929             if (score > best_score ||
930                 (count_diff < best_count_diff && score == best_score)) {
931                 best_score = score;
932                 best_idx   = j;
933                 best_count_diff = count_diff;
934             }
935         }
936         av_assert0(best_idx >= 0);
937         FFSWAP(uint64_t, outlink->in_channel_layouts->channel_layouts[0],
938                outlink->in_channel_layouts->channel_layouts[best_idx]);
939     }
940
941 }
942
943 static void swap_channel_layouts(AVFilterGraph *graph)
944 {
945     int i;
946
947     for (i = 0; i < graph->nb_filters; i++)
948         swap_channel_layouts_on_filter(graph->filters[i]);
949 }
950
951 static void swap_sample_fmts_on_filter(AVFilterContext *filter)
952 {
953     AVFilterLink *link = NULL;
954     int format, bps;
955     int i, j;
956
957     for (i = 0; i < filter->nb_inputs; i++) {
958         link = filter->inputs[i];
959
960         if (link->type == AVMEDIA_TYPE_AUDIO &&
961             link->out_formats->nb_formats == 1)
962             break;
963     }
964     if (i == filter->nb_inputs)
965         return;
966
967     format = link->out_formats->formats[0];
968     bps    = av_get_bytes_per_sample(format);
969
970     for (i = 0; i < filter->nb_outputs; i++) {
971         AVFilterLink *outlink = filter->outputs[i];
972         int best_idx = -1, best_score = INT_MIN;
973
974         if (outlink->type != AVMEDIA_TYPE_AUDIO ||
975             outlink->in_formats->nb_formats < 2)
976             continue;
977
978         for (j = 0; j < outlink->in_formats->nb_formats; j++) {
979             int out_format = outlink->in_formats->formats[j];
980             int out_bps    = av_get_bytes_per_sample(out_format);
981             int score;
982
983             if (av_get_packed_sample_fmt(out_format) == format ||
984                 av_get_planar_sample_fmt(out_format) == format) {
985                 best_idx   = j;
986                 break;
987             }
988
989             /* for s32 and float prefer double to prevent loss of information */
990             if (bps == 4 && out_bps == 8) {
991                 best_idx = j;
992                 break;
993             }
994
995             /* prefer closest higher or equal bps */
996             score = -abs(out_bps - bps);
997             if (out_bps >= bps)
998                 score += INT_MAX/2;
999
1000             if (score > best_score) {
1001                 best_score = score;
1002                 best_idx   = j;
1003             }
1004         }
1005         av_assert0(best_idx >= 0);
1006         FFSWAP(int, outlink->in_formats->formats[0],
1007                outlink->in_formats->formats[best_idx]);
1008     }
1009 }
1010
1011 static void swap_sample_fmts(AVFilterGraph *graph)
1012 {
1013     int i;
1014
1015     for (i = 0; i < graph->nb_filters; i++)
1016         swap_sample_fmts_on_filter(graph->filters[i]);
1017
1018 }
1019
1020 static int pick_formats(AVFilterGraph *graph)
1021 {
1022     int i, j, ret;
1023     int change;
1024
1025     do{
1026         change = 0;
1027         for (i = 0; i < graph->nb_filters; i++) {
1028             AVFilterContext *filter = graph->filters[i];
1029             if (filter->nb_inputs){
1030                 for (j = 0; j < filter->nb_inputs; j++){
1031                     if(filter->inputs[j]->in_formats && filter->inputs[j]->in_formats->nb_formats == 1) {
1032                         if ((ret = pick_format(filter->inputs[j], NULL)) < 0)
1033                             return ret;
1034                         change = 1;
1035                     }
1036                 }
1037             }
1038             if (filter->nb_outputs){
1039                 for (j = 0; j < filter->nb_outputs; j++){
1040                     if(filter->outputs[j]->in_formats && filter->outputs[j]->in_formats->nb_formats == 1) {
1041                         if ((ret = pick_format(filter->outputs[j], NULL)) < 0)
1042                             return ret;
1043                         change = 1;
1044                     }
1045                 }
1046             }
1047             if (filter->nb_inputs && filter->nb_outputs && filter->inputs[0]->format>=0) {
1048                 for (j = 0; j < filter->nb_outputs; j++) {
1049                     if(filter->outputs[j]->format<0) {
1050                         if ((ret = pick_format(filter->outputs[j], filter->inputs[0])) < 0)
1051                             return ret;
1052                         change = 1;
1053                     }
1054                 }
1055             }
1056         }
1057     }while(change);
1058
1059     for (i = 0; i < graph->nb_filters; i++) {
1060         AVFilterContext *filter = graph->filters[i];
1061
1062         for (j = 0; j < filter->nb_inputs; j++)
1063             if ((ret = pick_format(filter->inputs[j], NULL)) < 0)
1064                 return ret;
1065         for (j = 0; j < filter->nb_outputs; j++)
1066             if ((ret = pick_format(filter->outputs[j], NULL)) < 0)
1067                 return ret;
1068     }
1069     return 0;
1070 }
1071
1072 /**
1073  * Configure the formats of all the links in the graph.
1074  */
1075 static int graph_config_formats(AVFilterGraph *graph, AVClass *log_ctx)
1076 {
1077     int ret;
1078
1079     /* find supported formats from sub-filters, and merge along links */
1080     while ((ret = query_formats(graph, log_ctx)) == AVERROR(EAGAIN))
1081         av_log(graph, AV_LOG_DEBUG, "query_formats not finished\n");
1082     if (ret < 0)
1083         return ret;
1084
1085     /* Once everything is merged, it's possible that we'll still have
1086      * multiple valid media format choices. We try to minimize the amount
1087      * of format conversion inside filters */
1088     reduce_formats(graph);
1089
1090     /* for audio filters, ensure the best format, sample rate and channel layout
1091      * is selected */
1092     swap_sample_fmts(graph);
1093     swap_samplerates(graph);
1094     swap_channel_layouts(graph);
1095
1096     if ((ret = pick_formats(graph)) < 0)
1097         return ret;
1098
1099     return 0;
1100 }
1101
1102 static int ff_avfilter_graph_config_pointers(AVFilterGraph *graph,
1103                                              AVClass *log_ctx)
1104 {
1105     unsigned i, j;
1106     int sink_links_count = 0, n = 0;
1107     AVFilterContext *f;
1108     AVFilterLink **sinks;
1109
1110     for (i = 0; i < graph->nb_filters; i++) {
1111         f = graph->filters[i];
1112         for (j = 0; j < f->nb_inputs; j++) {
1113             f->inputs[j]->graph     = graph;
1114             f->inputs[j]->age_index = -1;
1115         }
1116         for (j = 0; j < f->nb_outputs; j++) {
1117             f->outputs[j]->graph    = graph;
1118             f->outputs[j]->age_index= -1;
1119         }
1120         if (!f->nb_outputs) {
1121             if (f->nb_inputs > INT_MAX - sink_links_count)
1122                 return AVERROR(EINVAL);
1123             sink_links_count += f->nb_inputs;
1124         }
1125     }
1126     sinks = av_calloc(sink_links_count, sizeof(*sinks));
1127     if (!sinks)
1128         return AVERROR(ENOMEM);
1129     for (i = 0; i < graph->nb_filters; i++) {
1130         f = graph->filters[i];
1131         if (!f->nb_outputs) {
1132             for (j = 0; j < f->nb_inputs; j++) {
1133                 sinks[n] = f->inputs[j];
1134                 f->inputs[j]->age_index = n++;
1135             }
1136         }
1137     }
1138     av_assert0(n == sink_links_count);
1139     graph->sink_links       = sinks;
1140     graph->sink_links_count = sink_links_count;
1141     return 0;
1142 }
1143
1144 static int graph_insert_fifos(AVFilterGraph *graph, AVClass *log_ctx)
1145 {
1146     AVFilterContext *f;
1147     int i, j, ret;
1148     int fifo_count = 0;
1149
1150     for (i = 0; i < graph->nb_filters; i++) {
1151         f = graph->filters[i];
1152
1153         for (j = 0; j < f->nb_inputs; j++) {
1154             AVFilterLink *link = f->inputs[j];
1155             AVFilterContext *fifo_ctx;
1156             AVFilter *fifo;
1157             char name[32];
1158
1159             if (!link->dstpad->needs_fifo)
1160                 continue;
1161
1162             fifo = f->inputs[j]->type == AVMEDIA_TYPE_VIDEO ?
1163                    avfilter_get_by_name("fifo") :
1164                    avfilter_get_by_name("afifo");
1165
1166             snprintf(name, sizeof(name), "auto-inserted fifo %d", fifo_count++);
1167
1168             ret = avfilter_graph_create_filter(&fifo_ctx, fifo, name, NULL,
1169                                                NULL, graph);
1170             if (ret < 0)
1171                 return ret;
1172
1173             ret = avfilter_insert_filter(link, fifo_ctx, 0, 0);
1174             if (ret < 0)
1175                 return ret;
1176         }
1177     }
1178
1179     return 0;
1180 }
1181
1182 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
1183 {
1184     int ret;
1185
1186     if ((ret = graph_check_validity(graphctx, log_ctx)))
1187         return ret;
1188     if ((ret = graph_insert_fifos(graphctx, log_ctx)) < 0)
1189         return ret;
1190     if ((ret = graph_config_formats(graphctx, log_ctx)))
1191         return ret;
1192     if ((ret = graph_config_links(graphctx, log_ctx)))
1193         return ret;
1194     if ((ret = ff_avfilter_graph_config_pointers(graphctx, log_ctx)))
1195         return ret;
1196
1197     return 0;
1198 }
1199
1200 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags)
1201 {
1202     int i, r = AVERROR(ENOSYS);
1203
1204     if (!graph)
1205         return r;
1206
1207     if ((flags & AVFILTER_CMD_FLAG_ONE) && !(flags & AVFILTER_CMD_FLAG_FAST)) {
1208         r = avfilter_graph_send_command(graph, target, cmd, arg, res, res_len, flags | AVFILTER_CMD_FLAG_FAST);
1209         if (r != AVERROR(ENOSYS))
1210             return r;
1211     }
1212
1213     if (res_len && res)
1214         res[0] = 0;
1215
1216     for (i = 0; i < graph->nb_filters; i++) {
1217         AVFilterContext *filter = graph->filters[i];
1218         if (!strcmp(target, "all") || (filter->name && !strcmp(target, filter->name)) || !strcmp(target, filter->filter->name)) {
1219             r = avfilter_process_command(filter, cmd, arg, res, res_len, flags);
1220             if (r != AVERROR(ENOSYS)) {
1221                 if ((flags & AVFILTER_CMD_FLAG_ONE) || r < 0)
1222                     return r;
1223             }
1224         }
1225     }
1226
1227     return r;
1228 }
1229
1230 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *command, const char *arg, int flags, double ts)
1231 {
1232     int i;
1233
1234     if(!graph)
1235         return 0;
1236
1237     for (i = 0; i < graph->nb_filters; i++) {
1238         AVFilterContext *filter = graph->filters[i];
1239         if(filter && (!strcmp(target, "all") || !strcmp(target, filter->name) || !strcmp(target, filter->filter->name))){
1240             AVFilterCommand **queue = &filter->command_queue, *next;
1241             while (*queue && (*queue)->time <= ts)
1242                 queue = &(*queue)->next;
1243             next = *queue;
1244             *queue = av_mallocz(sizeof(AVFilterCommand));
1245             (*queue)->command = av_strdup(command);
1246             (*queue)->arg     = av_strdup(arg);
1247             (*queue)->time    = ts;
1248             (*queue)->flags   = flags;
1249             (*queue)->next    = next;
1250             if(flags & AVFILTER_CMD_FLAG_ONE)
1251                 return 0;
1252         }
1253     }
1254
1255     return 0;
1256 }
1257
1258 static void heap_bubble_up(AVFilterGraph *graph,
1259                            AVFilterLink *link, int index)
1260 {
1261     AVFilterLink **links = graph->sink_links;
1262
1263     while (index) {
1264         int parent = (index - 1) >> 1;
1265         if (links[parent]->current_pts >= link->current_pts)
1266             break;
1267         links[index] = links[parent];
1268         links[index]->age_index = index;
1269         index = parent;
1270     }
1271     links[index] = link;
1272     link->age_index = index;
1273 }
1274
1275 static void heap_bubble_down(AVFilterGraph *graph,
1276                              AVFilterLink *link, int index)
1277 {
1278     AVFilterLink **links = graph->sink_links;
1279
1280     while (1) {
1281         int child = 2 * index + 1;
1282         if (child >= graph->sink_links_count)
1283             break;
1284         if (child + 1 < graph->sink_links_count &&
1285             links[child + 1]->current_pts < links[child]->current_pts)
1286             child++;
1287         if (link->current_pts < links[child]->current_pts)
1288             break;
1289         links[index] = links[child];
1290         links[index]->age_index = index;
1291         index = child;
1292     }
1293     links[index] = link;
1294     link->age_index = index;
1295 }
1296
1297 void ff_avfilter_graph_update_heap(AVFilterGraph *graph, AVFilterLink *link)
1298 {
1299     heap_bubble_up  (graph, link, link->age_index);
1300     heap_bubble_down(graph, link, link->age_index);
1301 }
1302
1303
1304 int avfilter_graph_request_oldest(AVFilterGraph *graph)
1305 {
1306     while (graph->sink_links_count) {
1307         AVFilterLink *oldest = graph->sink_links[0];
1308         int r = ff_request_frame(oldest);
1309         if (r != AVERROR_EOF)
1310             return r;
1311         av_log(oldest->dst, AV_LOG_DEBUG, "EOF on sink link %s:%s.\n",
1312                oldest->dst ? oldest->dst->name : "unknown",
1313                oldest->dstpad ? oldest->dstpad->name : "unknown");
1314         /* EOF: remove the link from the heap */
1315         if (oldest->age_index < --graph->sink_links_count)
1316             heap_bubble_down(graph, graph->sink_links[graph->sink_links_count],
1317                              oldest->age_index);
1318         oldest->age_index = -1;
1319     }
1320     return AVERROR_EOF;
1321 }