Move av_find_best_pix_fmt_of_2() from avcodec to avutil
[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
35 #include "avfilter.h"
36 #include "formats.h"
37 #include "internal.h"
38 #include "thread.h"
39
40 #define OFFSET(x) offsetof(AVFilterGraph, x)
41 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
42 static const AVOption filtergraph_options[] = {
43     { "thread_type", "Allowed thread types", OFFSET(thread_type), AV_OPT_TYPE_FLAGS,
44         { .i64 = AVFILTER_THREAD_SLICE }, 0, INT_MAX, FLAGS, "thread_type" },
45         { "slice", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AVFILTER_THREAD_SLICE }, .flags = FLAGS, .unit = "thread_type" },
46     { "threads",     "Maximum number of threads", OFFSET(nb_threads),
47         AV_OPT_TYPE_INT,   { .i64 = 0 }, 0, INT_MAX, FLAGS },
48     {"scale_sws_opts"       , "default scale filter options"        , OFFSET(scale_sws_opts)        ,
49         AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
50     {"aresample_swr_opts"   , "default aresample filter options"    , OFFSET(aresample_swr_opts)    ,
51         AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
52     { NULL },
53 };
54
55 static const AVClass filtergraph_class = {
56     .class_name = "AVFilterGraph",
57     .item_name  = av_default_item_name,
58     .version    = LIBAVUTIL_VERSION_INT,
59     .option     = filtergraph_options,
60     .category   = AV_CLASS_CATEGORY_FILTER,
61 };
62
63 #if !HAVE_THREADS
64 void ff_graph_thread_free(AVFilterGraph *graph)
65 {
66 }
67
68 int ff_graph_thread_init(AVFilterGraph *graph)
69 {
70     graph->thread_type = 0;
71     graph->nb_threads  = 1;
72     return 0;
73 }
74 #endif
75
76 AVFilterGraph *avfilter_graph_alloc(void)
77 {
78     AVFilterGraph *ret = av_mallocz(sizeof(*ret));
79     if (!ret)
80         return NULL;
81
82     ret->internal = av_mallocz(sizeof(*ret->internal));
83     if (!ret->internal) {
84         av_freep(&ret);
85         return NULL;
86     }
87
88     ret->av_class = &filtergraph_class;
89     av_opt_set_defaults(ret);
90
91     return ret;
92 }
93
94 void ff_filter_graph_remove_filter(AVFilterGraph *graph, AVFilterContext *filter)
95 {
96     int i;
97     for (i = 0; i < graph->nb_filters; i++) {
98         if (graph->filters[i] == filter) {
99             FFSWAP(AVFilterContext*, graph->filters[i],
100                    graph->filters[graph->nb_filters - 1]);
101             graph->nb_filters--;
102             return;
103         }
104     }
105 }
106
107 void avfilter_graph_free(AVFilterGraph **graph)
108 {
109     if (!*graph)
110         return;
111
112     while ((*graph)->nb_filters)
113         avfilter_free((*graph)->filters[0]);
114
115     ff_graph_thread_free(*graph);
116
117     av_freep(&(*graph)->sink_links);
118
119     av_freep(&(*graph)->scale_sws_opts);
120     av_freep(&(*graph)->aresample_swr_opts);
121     av_freep(&(*graph)->resample_lavr_opts);
122     av_freep(&(*graph)->filters);
123     av_freep(&(*graph)->internal);
124     av_freep(graph);
125 }
126
127 #if FF_API_AVFILTER_OPEN
128 int avfilter_graph_add_filter(AVFilterGraph *graph, AVFilterContext *filter)
129 {
130     AVFilterContext **filters = av_realloc(graph->filters,
131                                            sizeof(*filters) * (graph->nb_filters + 1));
132     if (!filters)
133         return AVERROR(ENOMEM);
134
135     graph->filters = filters;
136     graph->filters[graph->nb_filters++] = filter;
137
138 #if FF_API_FOO_COUNT
139 FF_DISABLE_DEPRECATION_WARNINGS
140     graph->filter_count_unused = graph->nb_filters;
141 FF_ENABLE_DEPRECATION_WARNINGS
142 #endif
143
144     filter->graph = graph;
145
146     return 0;
147 }
148 #endif
149
150 int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt,
151                                  const char *name, const char *args, void *opaque,
152                                  AVFilterGraph *graph_ctx)
153 {
154     int ret;
155
156     *filt_ctx = avfilter_graph_alloc_filter(graph_ctx, filt, name);
157     if (!*filt_ctx)
158         return AVERROR(ENOMEM);
159
160     ret = avfilter_init_str(*filt_ctx, args);
161     if (ret < 0)
162         goto fail;
163
164     return 0;
165
166 fail:
167     if (*filt_ctx)
168         avfilter_free(*filt_ctx);
169     *filt_ctx = NULL;
170     return ret;
171 }
172
173 void avfilter_graph_set_auto_convert(AVFilterGraph *graph, unsigned flags)
174 {
175     graph->disable_auto_convert = flags;
176 }
177
178 AVFilterContext *avfilter_graph_alloc_filter(AVFilterGraph *graph,
179                                              const AVFilter *filter,
180                                              const char *name)
181 {
182     AVFilterContext **filters, *s;
183
184     if (graph->thread_type && !graph->internal->thread_execute) {
185         if (graph->execute) {
186             graph->internal->thread_execute = graph->execute;
187         } else {
188             int ret = ff_graph_thread_init(graph);
189             if (ret < 0) {
190                 av_log(graph, AV_LOG_ERROR, "Error initializing threading.\n");
191                 return NULL;
192             }
193         }
194     }
195
196     s = ff_filter_alloc(filter, name);
197     if (!s)
198         return NULL;
199
200     filters = av_realloc(graph->filters, sizeof(*filters) * (graph->nb_filters + 1));
201     if (!filters) {
202         avfilter_free(s);
203         return NULL;
204     }
205
206     graph->filters = filters;
207     graph->filters[graph->nb_filters++] = s;
208
209 #if FF_API_FOO_COUNT
210 FF_DISABLE_DEPRECATION_WARNINGS
211     graph->filter_count_unused = graph->nb_filters;
212 FF_ENABLE_DEPRECATION_WARNINGS
213 #endif
214
215     s->graph = graph;
216
217     return s;
218 }
219
220 /**
221  * Check for the validity of graph.
222  *
223  * A graph is considered valid if all its input and output pads are
224  * connected.
225  *
226  * @return >= 0 in case of success, a negative value otherwise
227  */
228 static int graph_check_validity(AVFilterGraph *graph, AVClass *log_ctx)
229 {
230     AVFilterContext *filt;
231     int i, j;
232
233     for (i = 0; i < graph->nb_filters; i++) {
234         const AVFilterPad *pad;
235         filt = graph->filters[i];
236
237         for (j = 0; j < filt->nb_inputs; j++) {
238             if (!filt->inputs[j] || !filt->inputs[j]->src) {
239                 pad = &filt->input_pads[j];
240                 av_log(log_ctx, AV_LOG_ERROR,
241                        "Input pad \"%s\" with type %s of the filter instance \"%s\" of %s not connected to any source\n",
242                        pad->name, av_get_media_type_string(pad->type), filt->name, filt->filter->name);
243                 return AVERROR(EINVAL);
244             }
245         }
246
247         for (j = 0; j < filt->nb_outputs; j++) {
248             if (!filt->outputs[j] || !filt->outputs[j]->dst) {
249                 pad = &filt->output_pads[j];
250                 av_log(log_ctx, AV_LOG_ERROR,
251                        "Output pad \"%s\" with type %s of the filter instance \"%s\" of %s not connected to any destination\n",
252                        pad->name, av_get_media_type_string(pad->type), filt->name, filt->filter->name);
253                 return AVERROR(EINVAL);
254             }
255         }
256     }
257
258     return 0;
259 }
260
261 /**
262  * Configure all the links of graphctx.
263  *
264  * @return >= 0 in case of success, a negative value otherwise
265  */
266 static int graph_config_links(AVFilterGraph *graph, AVClass *log_ctx)
267 {
268     AVFilterContext *filt;
269     int i, ret;
270
271     for (i = 0; i < graph->nb_filters; i++) {
272         filt = graph->filters[i];
273
274         if (!filt->nb_outputs) {
275             if ((ret = avfilter_config_links(filt)))
276                 return ret;
277         }
278     }
279
280     return 0;
281 }
282
283 AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, const char *name)
284 {
285     int i;
286
287     for (i = 0; i < graph->nb_filters; i++)
288         if (graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
289             return graph->filters[i];
290
291     return NULL;
292 }
293
294 static void sanitize_channel_layouts(void *log, AVFilterChannelLayouts *l)
295 {
296     if (!l)
297         return;
298     if (l->nb_channel_layouts) {
299         if (l->all_layouts || l->all_counts)
300             av_log(log, AV_LOG_WARNING, "All layouts set on non-empty list\n");
301         l->all_layouts = l->all_counts = 0;
302     } else {
303         if (l->all_counts && !l->all_layouts)
304             av_log(log, AV_LOG_WARNING, "All counts without all layouts\n");
305         l->all_layouts = 1;
306     }
307 }
308
309 static int filter_query_formats(AVFilterContext *ctx)
310 {
311     int ret, i;
312     AVFilterFormats *formats;
313     AVFilterChannelLayouts *chlayouts;
314     AVFilterFormats *samplerates;
315     enum AVMediaType type = ctx->inputs  && ctx->inputs [0] ? ctx->inputs [0]->type :
316                             ctx->outputs && ctx->outputs[0] ? ctx->outputs[0]->type :
317                             AVMEDIA_TYPE_VIDEO;
318
319     if ((ret = ctx->filter->query_formats(ctx)) < 0) {
320         if (ret != AVERROR(EAGAIN))
321             av_log(ctx, AV_LOG_ERROR, "Query format failed for '%s': %s\n",
322                    ctx->name, av_err2str(ret));
323         return ret;
324     }
325
326     for (i = 0; i < ctx->nb_inputs; i++)
327         sanitize_channel_layouts(ctx, ctx->inputs[i]->out_channel_layouts);
328     for (i = 0; i < ctx->nb_outputs; i++)
329         sanitize_channel_layouts(ctx, ctx->outputs[i]->in_channel_layouts);
330
331     formats = ff_all_formats(type);
332     if (!formats)
333         return AVERROR(ENOMEM);
334     ff_set_common_formats(ctx, formats);
335     if (type == AVMEDIA_TYPE_AUDIO) {
336         samplerates = ff_all_samplerates();
337         if (!samplerates)
338             return AVERROR(ENOMEM);
339         ff_set_common_samplerates(ctx, samplerates);
340         chlayouts = ff_all_channel_layouts();
341         if (!chlayouts)
342             return AVERROR(ENOMEM);
343         ff_set_common_channel_layouts(ctx, chlayouts);
344     }
345     return 0;
346 }
347
348 static int formats_declared(AVFilterContext *f)
349 {
350     int i;
351
352     for (i = 0; i < f->nb_inputs; i++) {
353         if (!f->inputs[i]->out_formats)
354             return 0;
355         if (f->inputs[i]->type == AVMEDIA_TYPE_AUDIO &&
356             !(f->inputs[i]->out_samplerates &&
357               f->inputs[i]->out_channel_layouts))
358             return 0;
359     }
360     for (i = 0; i < f->nb_outputs; i++) {
361         if (!f->outputs[i]->in_formats)
362             return 0;
363         if (f->outputs[i]->type == AVMEDIA_TYPE_AUDIO &&
364             !(f->outputs[i]->in_samplerates &&
365               f->outputs[i]->in_channel_layouts))
366             return 0;
367     }
368     return 1;
369 }
370
371 static AVFilterFormats *clone_filter_formats(AVFilterFormats *arg)
372 {
373     AVFilterFormats *a = av_memdup(arg, sizeof(*arg));
374     if (a) {
375         a->refcount = 0;
376         a->refs     = NULL;
377         a->formats  = av_memdup(a->formats, sizeof(*a->formats) * a->nb_formats);
378         if (!a->formats && arg->formats)
379             av_freep(&a);
380     }
381     return a;
382 }
383
384 static int can_merge_formats(AVFilterFormats *a_arg,
385                              AVFilterFormats *b_arg,
386                              enum AVMediaType type,
387                              int is_sample_rate)
388 {
389     AVFilterFormats *a, *b, *ret;
390     if (a_arg == b_arg)
391         return 1;
392     a = clone_filter_formats(a_arg);
393     b = clone_filter_formats(b_arg);
394
395     if (!a || !b) {
396         if (a)
397             av_freep(&a->formats);
398         if (b)
399             av_freep(&b->formats);
400
401         av_freep(&a);
402         av_freep(&b);
403
404         return 0;
405     }
406
407     if (is_sample_rate) {
408         ret = ff_merge_samplerates(a, b);
409     } else {
410         ret = ff_merge_formats(a, b, type);
411     }
412     if (ret) {
413         av_freep(&ret->formats);
414         av_freep(&ret->refs);
415         av_freep(&ret);
416         return 1;
417     } else {
418         av_freep(&a->formats);
419         av_freep(&b->formats);
420         av_freep(&a);
421         av_freep(&b);
422         return 0;
423     }
424 }
425
426 /**
427  * Perform one round of query_formats() and merging formats lists on the
428  * filter graph.
429  * @return  >=0 if all links formats lists could be queried and merged;
430  *          AVERROR(EAGAIN) some progress was made in the queries or merging
431  *          and a later call may succeed;
432  *          AVERROR(EIO) (may be changed) plus a log message if no progress
433  *          was made and the negotiation is stuck;
434  *          a negative error code if some other error happened
435  */
436 static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
437 {
438     int i, j, ret;
439     int scaler_count = 0, resampler_count = 0;
440     int count_queried = 0;        /* successful calls to query_formats() */
441     int count_merged = 0;         /* successful merge of formats lists */
442     int count_already_merged = 0; /* lists already merged */
443     int count_delayed = 0;        /* lists that need to be merged later */
444
445     for (i = 0; i < graph->nb_filters; i++) {
446         AVFilterContext *f = graph->filters[i];
447         if (formats_declared(f))
448             continue;
449         if (f->filter->query_formats)
450             ret = filter_query_formats(f);
451         else
452             ret = ff_default_query_formats(f);
453         if (ret < 0 && ret != AVERROR(EAGAIN))
454             return ret;
455         /* note: EAGAIN could indicate a partial success, not counted yet */
456         count_queried += ret >= 0;
457     }
458
459     /* go through and merge as many format lists as possible */
460     for (i = 0; i < graph->nb_filters; i++) {
461         AVFilterContext *filter = graph->filters[i];
462
463         for (j = 0; j < filter->nb_inputs; j++) {
464             AVFilterLink *link = filter->inputs[j];
465             int convert_needed = 0;
466
467             if (!link)
468                 continue;
469
470             if (link->in_formats != link->out_formats
471                 && link->in_formats && link->out_formats)
472                 if (!can_merge_formats(link->in_formats, link->out_formats,
473                                       link->type, 0))
474                     convert_needed = 1;
475             if (link->type == AVMEDIA_TYPE_AUDIO) {
476                 if (link->in_samplerates != link->out_samplerates
477                     && link->in_samplerates && link->out_samplerates)
478                     if (!can_merge_formats(link->in_samplerates,
479                                            link->out_samplerates,
480                                            0, 1))
481                         convert_needed = 1;
482             }
483
484 #define MERGE_DISPATCH(field, statement)                                     \
485             if (!(link->in_ ## field && link->out_ ## field)) {              \
486                 count_delayed++;                                             \
487             } else if (link->in_ ## field == link->out_ ## field) {          \
488                 count_already_merged++;                                      \
489             } else if (!convert_needed) {                                    \
490                 count_merged++;                                              \
491                 statement                                                    \
492             }
493
494             if (link->type == AVMEDIA_TYPE_AUDIO) {
495                 MERGE_DISPATCH(channel_layouts,
496                     if (!ff_merge_channel_layouts(link->in_channel_layouts,
497                                                   link->out_channel_layouts))
498                         convert_needed = 1;
499                 )
500                 MERGE_DISPATCH(samplerates,
501                     if (!ff_merge_samplerates(link->in_samplerates,
502                                               link->out_samplerates))
503                         convert_needed = 1;
504                 )
505             }
506             MERGE_DISPATCH(formats,
507                 if (!ff_merge_formats(link->in_formats, link->out_formats,
508                                       link->type))
509                     convert_needed = 1;
510             )
511 #undef MERGE_DISPATCH
512
513             if (convert_needed) {
514                 AVFilterContext *convert;
515                 AVFilter *filter;
516                 AVFilterLink *inlink, *outlink;
517                 char scale_args[256];
518                 char inst_name[30];
519
520                 /* couldn't merge format lists. auto-insert conversion filter */
521                 switch (link->type) {
522                 case AVMEDIA_TYPE_VIDEO:
523                     if (!(filter = avfilter_get_by_name("scale"))) {
524                         av_log(log_ctx, AV_LOG_ERROR, "'scale' filter "
525                                "not present, cannot convert pixel formats.\n");
526                         return AVERROR(EINVAL);
527                     }
528
529                     snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d",
530                              scaler_count++);
531
532                     if ((ret = avfilter_graph_create_filter(&convert, filter,
533                                                             inst_name, graph->scale_sws_opts, NULL,
534                                                             graph)) < 0)
535                         return ret;
536                     break;
537                 case AVMEDIA_TYPE_AUDIO:
538                     if (!(filter = avfilter_get_by_name("aresample"))) {
539                         av_log(log_ctx, AV_LOG_ERROR, "'aresample' filter "
540                                "not present, cannot convert audio formats.\n");
541                         return AVERROR(EINVAL);
542                     }
543
544                     snprintf(inst_name, sizeof(inst_name), "auto-inserted resampler %d",
545                              resampler_count++);
546                     scale_args[0] = '\0';
547                     if (graph->aresample_swr_opts)
548                         snprintf(scale_args, sizeof(scale_args), "%s",
549                                  graph->aresample_swr_opts);
550                     if ((ret = avfilter_graph_create_filter(&convert, filter,
551                                                             inst_name, graph->aresample_swr_opts,
552                                                             NULL, graph)) < 0)
553                         return ret;
554                     break;
555                 default:
556                     return AVERROR(EINVAL);
557                 }
558
559                 if ((ret = avfilter_insert_filter(link, convert, 0, 0)) < 0)
560                     return ret;
561
562                 filter_query_formats(convert);
563                 inlink  = convert->inputs[0];
564                 outlink = convert->outputs[0];
565                 if (!ff_merge_formats( inlink->in_formats,  inlink->out_formats,  inlink->type) ||
566                     !ff_merge_formats(outlink->in_formats, outlink->out_formats, outlink->type))
567                     ret |= AVERROR(ENOSYS);
568                 if (inlink->type == AVMEDIA_TYPE_AUDIO &&
569                     (!ff_merge_samplerates(inlink->in_samplerates,
570                                            inlink->out_samplerates) ||
571                      !ff_merge_channel_layouts(inlink->in_channel_layouts,
572                                                inlink->out_channel_layouts)))
573                     ret |= AVERROR(ENOSYS);
574                 if (outlink->type == AVMEDIA_TYPE_AUDIO &&
575                     (!ff_merge_samplerates(outlink->in_samplerates,
576                                            outlink->out_samplerates) ||
577                      !ff_merge_channel_layouts(outlink->in_channel_layouts,
578                                                outlink->out_channel_layouts)))
579                     ret |= AVERROR(ENOSYS);
580
581                 if (ret < 0) {
582                     av_log(log_ctx, AV_LOG_ERROR,
583                            "Impossible to convert between the formats supported by the filter "
584                            "'%s' and the filter '%s'\n", link->src->name, link->dst->name);
585                     return ret;
586                 }
587             }
588         }
589     }
590
591     av_log(graph, AV_LOG_DEBUG, "query_formats: "
592            "%d queried, %d merged, %d already done, %d delayed\n",
593            count_queried, count_merged, count_already_merged, count_delayed);
594     if (count_delayed) {
595         AVBPrint bp;
596
597         /* if count_queried > 0, one filter at least did set its formats,
598            that will give additional information to its neighbour;
599            if count_merged > 0, one pair of formats lists at least was merged,
600            that will give additional information to all connected filters;
601            in both cases, progress was made and a new round must be done */
602         if (count_queried || count_merged)
603             return AVERROR(EAGAIN);
604         av_bprint_init(&bp, 0, AV_BPRINT_SIZE_AUTOMATIC);
605         for (i = 0; i < graph->nb_filters; i++)
606             if (!formats_declared(graph->filters[i]))
607                 av_bprintf(&bp, "%s%s", bp.len ? ", " : "",
608                           graph->filters[i]->name);
609         av_log(graph, AV_LOG_ERROR,
610                "The following filters could not choose their formats: %s\n"
611                "Consider inserting the (a)format filter near their input or "
612                "output.\n", bp.str);
613         return AVERROR(EIO);
614     }
615     return 0;
616 }
617
618 static int pick_format(AVFilterLink *link, AVFilterLink *ref)
619 {
620     if (!link || !link->in_formats)
621         return 0;
622
623     if (link->type == AVMEDIA_TYPE_VIDEO) {
624         if(ref && ref->type == AVMEDIA_TYPE_VIDEO){
625             int has_alpha= av_pix_fmt_desc_get(ref->format)->nb_components % 2 == 0;
626             enum AVPixelFormat best= AV_PIX_FMT_NONE;
627             int i;
628             for (i=0; i<link->in_formats->nb_formats; i++) {
629                 enum AVPixelFormat p = link->in_formats->formats[i];
630                 best= av_find_best_pix_fmt_of_2(best, p, ref->format, has_alpha, NULL);
631             }
632             av_log(link->src,AV_LOG_DEBUG, "picking %s out of %d ref:%s alpha:%d\n",
633                    av_get_pix_fmt_name(best), link->in_formats->nb_formats,
634                    av_get_pix_fmt_name(ref->format), has_alpha);
635             link->in_formats->formats[0] = best;
636         }
637     }
638
639     link->in_formats->nb_formats = 1;
640     link->format = link->in_formats->formats[0];
641
642     if (link->type == AVMEDIA_TYPE_AUDIO) {
643         if (!link->in_samplerates->nb_formats) {
644             av_log(link->src, AV_LOG_ERROR, "Cannot select sample rate for"
645                    " the link between filters %s and %s.\n", link->src->name,
646                    link->dst->name);
647             return AVERROR(EINVAL);
648         }
649         link->in_samplerates->nb_formats = 1;
650         link->sample_rate = link->in_samplerates->formats[0];
651
652         if (link->in_channel_layouts->all_layouts) {
653             av_log(link->src, AV_LOG_ERROR, "Cannot select channel layout for"
654                    " the link between filters %s and %s.\n", link->src->name,
655                    link->dst->name);
656             if (!link->in_channel_layouts->all_counts)
657                 av_log(link->src, AV_LOG_ERROR, "Unknown channel layouts not "
658                        "supported, try specifying a channel layout using "
659                        "'aformat=channel_layouts=something'.\n");
660             return AVERROR(EINVAL);
661         }
662         link->in_channel_layouts->nb_channel_layouts = 1;
663         link->channel_layout = link->in_channel_layouts->channel_layouts[0];
664         if ((link->channels = FF_LAYOUT2COUNT(link->channel_layout)))
665             link->channel_layout = 0;
666         else
667             link->channels = av_get_channel_layout_nb_channels(link->channel_layout);
668     }
669
670     ff_formats_unref(&link->in_formats);
671     ff_formats_unref(&link->out_formats);
672     ff_formats_unref(&link->in_samplerates);
673     ff_formats_unref(&link->out_samplerates);
674     ff_channel_layouts_unref(&link->in_channel_layouts);
675     ff_channel_layouts_unref(&link->out_channel_layouts);
676
677     return 0;
678 }
679
680 #define REDUCE_FORMATS(fmt_type, list_type, list, var, nb, add_format) \
681 do {                                                                   \
682     for (i = 0; i < filter->nb_inputs; i++) {                          \
683         AVFilterLink *link = filter->inputs[i];                        \
684         fmt_type fmt;                                                  \
685                                                                        \
686         if (!link->out_ ## list || link->out_ ## list->nb != 1)        \
687             continue;                                                  \
688         fmt = link->out_ ## list->var[0];                              \
689                                                                        \
690         for (j = 0; j < filter->nb_outputs; j++) {                     \
691             AVFilterLink *out_link = filter->outputs[j];               \
692             list_type *fmts;                                           \
693                                                                        \
694             if (link->type != out_link->type ||                        \
695                 out_link->in_ ## list->nb == 1)                        \
696                 continue;                                              \
697             fmts = out_link->in_ ## list;                              \
698                                                                        \
699             if (!out_link->in_ ## list->nb) {                          \
700                 add_format(&out_link->in_ ##list, fmt);                \
701                 ret = 1;                                               \
702                 break;                                                 \
703             }                                                          \
704                                                                        \
705             for (k = 0; k < out_link->in_ ## list->nb; k++)            \
706                 if (fmts->var[k] == fmt) {                             \
707                     fmts->var[0]  = fmt;                               \
708                     fmts->nb = 1;                                      \
709                     ret = 1;                                           \
710                     break;                                             \
711                 }                                                      \
712         }                                                              \
713     }                                                                  \
714 } while (0)
715
716 static int reduce_formats_on_filter(AVFilterContext *filter)
717 {
718     int i, j, k, ret = 0;
719
720     REDUCE_FORMATS(int,      AVFilterFormats,        formats,         formats,
721                    nb_formats, ff_add_format);
722     REDUCE_FORMATS(int,      AVFilterFormats,        samplerates,     formats,
723                    nb_formats, ff_add_format);
724
725     /* reduce channel layouts */
726     for (i = 0; i < filter->nb_inputs; i++) {
727         AVFilterLink *inlink = filter->inputs[i];
728         uint64_t fmt;
729
730         if (!inlink->out_channel_layouts ||
731             inlink->out_channel_layouts->nb_channel_layouts != 1)
732             continue;
733         fmt = inlink->out_channel_layouts->channel_layouts[0];
734
735         for (j = 0; j < filter->nb_outputs; j++) {
736             AVFilterLink *outlink = filter->outputs[j];
737             AVFilterChannelLayouts *fmts;
738
739             fmts = outlink->in_channel_layouts;
740             if (inlink->type != outlink->type || fmts->nb_channel_layouts == 1)
741                 continue;
742
743             if (fmts->all_layouts &&
744                 (!FF_LAYOUT2COUNT(fmt) || fmts->all_counts)) {
745                 /* Turn the infinite list into a singleton */
746                 fmts->all_layouts = fmts->all_counts  = 0;
747                 ff_add_channel_layout(&outlink->in_channel_layouts, fmt);
748                 break;
749             }
750
751             for (k = 0; k < outlink->in_channel_layouts->nb_channel_layouts; k++) {
752                 if (fmts->channel_layouts[k] == fmt) {
753                     fmts->channel_layouts[0]  = fmt;
754                     fmts->nb_channel_layouts = 1;
755                     ret = 1;
756                     break;
757                 }
758             }
759         }
760     }
761
762     return ret;
763 }
764
765 static void reduce_formats(AVFilterGraph *graph)
766 {
767     int i, reduced;
768
769     do {
770         reduced = 0;
771
772         for (i = 0; i < graph->nb_filters; i++)
773             reduced |= reduce_formats_on_filter(graph->filters[i]);
774     } while (reduced);
775 }
776
777 static void swap_samplerates_on_filter(AVFilterContext *filter)
778 {
779     AVFilterLink *link = NULL;
780     int sample_rate;
781     int i, j;
782
783     for (i = 0; i < filter->nb_inputs; i++) {
784         link = filter->inputs[i];
785
786         if (link->type == AVMEDIA_TYPE_AUDIO &&
787             link->out_samplerates->nb_formats== 1)
788             break;
789     }
790     if (i == filter->nb_inputs)
791         return;
792
793     sample_rate = link->out_samplerates->formats[0];
794
795     for (i = 0; i < filter->nb_outputs; i++) {
796         AVFilterLink *outlink = filter->outputs[i];
797         int best_idx, best_diff = INT_MAX;
798
799         if (outlink->type != AVMEDIA_TYPE_AUDIO ||
800             outlink->in_samplerates->nb_formats < 2)
801             continue;
802
803         for (j = 0; j < outlink->in_samplerates->nb_formats; j++) {
804             int diff = abs(sample_rate - outlink->in_samplerates->formats[j]);
805
806             if (diff < best_diff) {
807                 best_diff = diff;
808                 best_idx  = j;
809             }
810         }
811         FFSWAP(int, outlink->in_samplerates->formats[0],
812                outlink->in_samplerates->formats[best_idx]);
813     }
814 }
815
816 static void swap_samplerates(AVFilterGraph *graph)
817 {
818     int i;
819
820     for (i = 0; i < graph->nb_filters; i++)
821         swap_samplerates_on_filter(graph->filters[i]);
822 }
823
824 #define CH_CENTER_PAIR (AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER)
825 #define CH_FRONT_PAIR  (AV_CH_FRONT_LEFT           | AV_CH_FRONT_RIGHT)
826 #define CH_STEREO_PAIR (AV_CH_STEREO_LEFT          | AV_CH_STEREO_RIGHT)
827 #define CH_WIDE_PAIR   (AV_CH_WIDE_LEFT            | AV_CH_WIDE_RIGHT)
828 #define CH_SIDE_PAIR   (AV_CH_SIDE_LEFT            | AV_CH_SIDE_RIGHT)
829 #define CH_DIRECT_PAIR (AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT)
830 #define CH_BACK_PAIR   (AV_CH_BACK_LEFT            | AV_CH_BACK_RIGHT)
831
832 /* allowable substitutions for channel pairs when comparing layouts,
833  * ordered by priority for both values */
834 static const uint64_t ch_subst[][2] = {
835     { CH_FRONT_PAIR,      CH_CENTER_PAIR     },
836     { CH_FRONT_PAIR,      CH_WIDE_PAIR       },
837     { CH_FRONT_PAIR,      AV_CH_FRONT_CENTER },
838     { CH_CENTER_PAIR,     CH_FRONT_PAIR      },
839     { CH_CENTER_PAIR,     CH_WIDE_PAIR       },
840     { CH_CENTER_PAIR,     AV_CH_FRONT_CENTER },
841     { CH_WIDE_PAIR,       CH_FRONT_PAIR      },
842     { CH_WIDE_PAIR,       CH_CENTER_PAIR     },
843     { CH_WIDE_PAIR,       AV_CH_FRONT_CENTER },
844     { AV_CH_FRONT_CENTER, CH_FRONT_PAIR      },
845     { AV_CH_FRONT_CENTER, CH_CENTER_PAIR     },
846     { AV_CH_FRONT_CENTER, CH_WIDE_PAIR       },
847     { CH_SIDE_PAIR,       CH_DIRECT_PAIR     },
848     { CH_SIDE_PAIR,       CH_BACK_PAIR       },
849     { CH_SIDE_PAIR,       AV_CH_BACK_CENTER  },
850     { CH_BACK_PAIR,       CH_DIRECT_PAIR     },
851     { CH_BACK_PAIR,       CH_SIDE_PAIR       },
852     { CH_BACK_PAIR,       AV_CH_BACK_CENTER  },
853     { AV_CH_BACK_CENTER,  CH_BACK_PAIR       },
854     { AV_CH_BACK_CENTER,  CH_DIRECT_PAIR     },
855     { AV_CH_BACK_CENTER,  CH_SIDE_PAIR       },
856 };
857
858 static void swap_channel_layouts_on_filter(AVFilterContext *filter)
859 {
860     AVFilterLink *link = NULL;
861     int i, j, k;
862
863     for (i = 0; i < filter->nb_inputs; i++) {
864         link = filter->inputs[i];
865
866         if (link->type == AVMEDIA_TYPE_AUDIO &&
867             link->out_channel_layouts->nb_channel_layouts == 1)
868             break;
869     }
870     if (i == filter->nb_inputs)
871         return;
872
873     for (i = 0; i < filter->nb_outputs; i++) {
874         AVFilterLink *outlink = filter->outputs[i];
875         int best_idx = -1, best_score = INT_MIN, best_count_diff = INT_MAX;
876
877         if (outlink->type != AVMEDIA_TYPE_AUDIO ||
878             outlink->in_channel_layouts->nb_channel_layouts < 2)
879             continue;
880
881         for (j = 0; j < outlink->in_channel_layouts->nb_channel_layouts; j++) {
882             uint64_t  in_chlayout = link->out_channel_layouts->channel_layouts[0];
883             uint64_t out_chlayout = outlink->in_channel_layouts->channel_layouts[j];
884             int  in_channels      = av_get_channel_layout_nb_channels(in_chlayout);
885             int out_channels      = av_get_channel_layout_nb_channels(out_chlayout);
886             int count_diff        = out_channels - in_channels;
887             int matched_channels, extra_channels;
888             int score = 100000;
889
890             if (FF_LAYOUT2COUNT(in_chlayout) || FF_LAYOUT2COUNT(out_chlayout)) {
891                 /* Compute score in case the input or output layout encodes
892                    a channel count; in this case the score is not altered by
893                    the computation afterwards, as in_chlayout and
894                    out_chlayout have both been set to 0 */
895                 if (FF_LAYOUT2COUNT(in_chlayout))
896                     in_channels = FF_LAYOUT2COUNT(in_chlayout);
897                 if (FF_LAYOUT2COUNT(out_chlayout))
898                     out_channels = FF_LAYOUT2COUNT(out_chlayout);
899                 score -= 10000 + FFABS(out_channels - in_channels) +
900                          (in_channels > out_channels ? 10000 : 0);
901                 in_chlayout = out_chlayout = 0;
902                 /* Let the remaining computation run, even if the score
903                    value is not altered */
904             }
905
906             /* channel substitution */
907             for (k = 0; k < FF_ARRAY_ELEMS(ch_subst); k++) {
908                 uint64_t cmp0 = ch_subst[k][0];
909                 uint64_t cmp1 = ch_subst[k][1];
910                 if (( in_chlayout & cmp0) && (!(out_chlayout & cmp0)) &&
911                     (out_chlayout & cmp1) && (!( in_chlayout & cmp1))) {
912                     in_chlayout  &= ~cmp0;
913                     out_chlayout &= ~cmp1;
914                     /* add score for channel match, minus a deduction for
915                        having to do the substitution */
916                     score += 10 * av_get_channel_layout_nb_channels(cmp1) - 2;
917                 }
918             }
919
920             /* no penalty for LFE channel mismatch */
921             if ( (in_chlayout & AV_CH_LOW_FREQUENCY) &&
922                 (out_chlayout & AV_CH_LOW_FREQUENCY))
923                 score += 10;
924             in_chlayout  &= ~AV_CH_LOW_FREQUENCY;
925             out_chlayout &= ~AV_CH_LOW_FREQUENCY;
926
927             matched_channels = av_get_channel_layout_nb_channels(in_chlayout &
928                                                                  out_chlayout);
929             extra_channels   = av_get_channel_layout_nb_channels(out_chlayout &
930                                                                  (~in_chlayout));
931             score += 10 * matched_channels - 5 * extra_channels;
932
933             if (score > best_score ||
934                 (count_diff < best_count_diff && score == best_score)) {
935                 best_score = score;
936                 best_idx   = j;
937                 best_count_diff = count_diff;
938             }
939         }
940         av_assert0(best_idx >= 0);
941         FFSWAP(uint64_t, outlink->in_channel_layouts->channel_layouts[0],
942                outlink->in_channel_layouts->channel_layouts[best_idx]);
943     }
944
945 }
946
947 static void swap_channel_layouts(AVFilterGraph *graph)
948 {
949     int i;
950
951     for (i = 0; i < graph->nb_filters; i++)
952         swap_channel_layouts_on_filter(graph->filters[i]);
953 }
954
955 static void swap_sample_fmts_on_filter(AVFilterContext *filter)
956 {
957     AVFilterLink *link = NULL;
958     int format, bps;
959     int i, j;
960
961     for (i = 0; i < filter->nb_inputs; i++) {
962         link = filter->inputs[i];
963
964         if (link->type == AVMEDIA_TYPE_AUDIO &&
965             link->out_formats->nb_formats == 1)
966             break;
967     }
968     if (i == filter->nb_inputs)
969         return;
970
971     format = link->out_formats->formats[0];
972     bps    = av_get_bytes_per_sample(format);
973
974     for (i = 0; i < filter->nb_outputs; i++) {
975         AVFilterLink *outlink = filter->outputs[i];
976         int best_idx = -1, best_score = INT_MIN;
977
978         if (outlink->type != AVMEDIA_TYPE_AUDIO ||
979             outlink->in_formats->nb_formats < 2)
980             continue;
981
982         for (j = 0; j < outlink->in_formats->nb_formats; j++) {
983             int out_format = outlink->in_formats->formats[j];
984             int out_bps    = av_get_bytes_per_sample(out_format);
985             int score;
986
987             if (av_get_packed_sample_fmt(out_format) == format ||
988                 av_get_planar_sample_fmt(out_format) == format) {
989                 best_idx   = j;
990                 break;
991             }
992
993             /* for s32 and float prefer double to prevent loss of information */
994             if (bps == 4 && out_bps == 8) {
995                 best_idx = j;
996                 break;
997             }
998
999             /* prefer closest higher or equal bps */
1000             score = -abs(out_bps - bps);
1001             if (out_bps >= bps)
1002                 score += INT_MAX/2;
1003
1004             if (score > best_score) {
1005                 best_score = score;
1006                 best_idx   = j;
1007             }
1008         }
1009         av_assert0(best_idx >= 0);
1010         FFSWAP(int, outlink->in_formats->formats[0],
1011                outlink->in_formats->formats[best_idx]);
1012     }
1013 }
1014
1015 static void swap_sample_fmts(AVFilterGraph *graph)
1016 {
1017     int i;
1018
1019     for (i = 0; i < graph->nb_filters; i++)
1020         swap_sample_fmts_on_filter(graph->filters[i]);
1021
1022 }
1023
1024 static int pick_formats(AVFilterGraph *graph)
1025 {
1026     int i, j, ret;
1027     int change;
1028
1029     do{
1030         change = 0;
1031         for (i = 0; i < graph->nb_filters; i++) {
1032             AVFilterContext *filter = graph->filters[i];
1033             if (filter->nb_inputs){
1034                 for (j = 0; j < filter->nb_inputs; j++){
1035                     if(filter->inputs[j]->in_formats && filter->inputs[j]->in_formats->nb_formats == 1) {
1036                         if ((ret = pick_format(filter->inputs[j], NULL)) < 0)
1037                             return ret;
1038                         change = 1;
1039                     }
1040                 }
1041             }
1042             if (filter->nb_outputs){
1043                 for (j = 0; j < filter->nb_outputs; j++){
1044                     if(filter->outputs[j]->in_formats && filter->outputs[j]->in_formats->nb_formats == 1) {
1045                         if ((ret = pick_format(filter->outputs[j], NULL)) < 0)
1046                             return ret;
1047                         change = 1;
1048                     }
1049                 }
1050             }
1051             if (filter->nb_inputs && filter->nb_outputs && filter->inputs[0]->format>=0) {
1052                 for (j = 0; j < filter->nb_outputs; j++) {
1053                     if(filter->outputs[j]->format<0) {
1054                         if ((ret = pick_format(filter->outputs[j], filter->inputs[0])) < 0)
1055                             return ret;
1056                         change = 1;
1057                     }
1058                 }
1059             }
1060         }
1061     }while(change);
1062
1063     for (i = 0; i < graph->nb_filters; i++) {
1064         AVFilterContext *filter = graph->filters[i];
1065
1066         for (j = 0; j < filter->nb_inputs; j++)
1067             if ((ret = pick_format(filter->inputs[j], NULL)) < 0)
1068                 return ret;
1069         for (j = 0; j < filter->nb_outputs; j++)
1070             if ((ret = pick_format(filter->outputs[j], NULL)) < 0)
1071                 return ret;
1072     }
1073     return 0;
1074 }
1075
1076 /**
1077  * Configure the formats of all the links in the graph.
1078  */
1079 static int graph_config_formats(AVFilterGraph *graph, AVClass *log_ctx)
1080 {
1081     int ret;
1082
1083     /* find supported formats from sub-filters, and merge along links */
1084     while ((ret = query_formats(graph, log_ctx)) == AVERROR(EAGAIN))
1085         av_log(graph, AV_LOG_DEBUG, "query_formats not finished\n");
1086     if (ret < 0)
1087         return ret;
1088
1089     /* Once everything is merged, it's possible that we'll still have
1090      * multiple valid media format choices. We try to minimize the amount
1091      * of format conversion inside filters */
1092     reduce_formats(graph);
1093
1094     /* for audio filters, ensure the best format, sample rate and channel layout
1095      * is selected */
1096     swap_sample_fmts(graph);
1097     swap_samplerates(graph);
1098     swap_channel_layouts(graph);
1099
1100     if ((ret = pick_formats(graph)) < 0)
1101         return ret;
1102
1103     return 0;
1104 }
1105
1106 static int ff_avfilter_graph_config_pointers(AVFilterGraph *graph,
1107                                              AVClass *log_ctx)
1108 {
1109     unsigned i, j;
1110     int sink_links_count = 0, n = 0;
1111     AVFilterContext *f;
1112     AVFilterLink **sinks;
1113
1114     for (i = 0; i < graph->nb_filters; i++) {
1115         f = graph->filters[i];
1116         for (j = 0; j < f->nb_inputs; j++) {
1117             f->inputs[j]->graph     = graph;
1118             f->inputs[j]->age_index = -1;
1119         }
1120         for (j = 0; j < f->nb_outputs; j++) {
1121             f->outputs[j]->graph    = graph;
1122             f->outputs[j]->age_index= -1;
1123         }
1124         if (!f->nb_outputs) {
1125             if (f->nb_inputs > INT_MAX - sink_links_count)
1126                 return AVERROR(EINVAL);
1127             sink_links_count += f->nb_inputs;
1128         }
1129     }
1130     sinks = av_calloc(sink_links_count, sizeof(*sinks));
1131     if (!sinks)
1132         return AVERROR(ENOMEM);
1133     for (i = 0; i < graph->nb_filters; i++) {
1134         f = graph->filters[i];
1135         if (!f->nb_outputs) {
1136             for (j = 0; j < f->nb_inputs; j++) {
1137                 sinks[n] = f->inputs[j];
1138                 f->inputs[j]->age_index = n++;
1139             }
1140         }
1141     }
1142     av_assert0(n == sink_links_count);
1143     graph->sink_links       = sinks;
1144     graph->sink_links_count = sink_links_count;
1145     return 0;
1146 }
1147
1148 static int graph_insert_fifos(AVFilterGraph *graph, AVClass *log_ctx)
1149 {
1150     AVFilterContext *f;
1151     int i, j, ret;
1152     int fifo_count = 0;
1153
1154     for (i = 0; i < graph->nb_filters; i++) {
1155         f = graph->filters[i];
1156
1157         for (j = 0; j < f->nb_inputs; j++) {
1158             AVFilterLink *link = f->inputs[j];
1159             AVFilterContext *fifo_ctx;
1160             AVFilter *fifo;
1161             char name[32];
1162
1163             if (!link->dstpad->needs_fifo)
1164                 continue;
1165
1166             fifo = f->inputs[j]->type == AVMEDIA_TYPE_VIDEO ?
1167                    avfilter_get_by_name("fifo") :
1168                    avfilter_get_by_name("afifo");
1169
1170             snprintf(name, sizeof(name), "auto-inserted fifo %d", fifo_count++);
1171
1172             ret = avfilter_graph_create_filter(&fifo_ctx, fifo, name, NULL,
1173                                                NULL, graph);
1174             if (ret < 0)
1175                 return ret;
1176
1177             ret = avfilter_insert_filter(link, fifo_ctx, 0, 0);
1178             if (ret < 0)
1179                 return ret;
1180         }
1181     }
1182
1183     return 0;
1184 }
1185
1186 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
1187 {
1188     int ret;
1189
1190     if ((ret = graph_check_validity(graphctx, log_ctx)))
1191         return ret;
1192     if ((ret = graph_insert_fifos(graphctx, log_ctx)) < 0)
1193         return ret;
1194     if ((ret = graph_config_formats(graphctx, log_ctx)))
1195         return ret;
1196     if ((ret = graph_config_links(graphctx, log_ctx)))
1197         return ret;
1198     if ((ret = ff_avfilter_graph_config_pointers(graphctx, log_ctx)))
1199         return ret;
1200
1201     return 0;
1202 }
1203
1204 int avfilter_graph_send_command(AVFilterGraph *graph, const char *target, const char *cmd, const char *arg, char *res, int res_len, int flags)
1205 {
1206     int i, r = AVERROR(ENOSYS);
1207
1208     if (!graph)
1209         return r;
1210
1211     if ((flags & AVFILTER_CMD_FLAG_ONE) && !(flags & AVFILTER_CMD_FLAG_FAST)) {
1212         r = avfilter_graph_send_command(graph, target, cmd, arg, res, res_len, flags | AVFILTER_CMD_FLAG_FAST);
1213         if (r != AVERROR(ENOSYS))
1214             return r;
1215     }
1216
1217     if (res_len && res)
1218         res[0] = 0;
1219
1220     for (i = 0; i < graph->nb_filters; i++) {
1221         AVFilterContext *filter = graph->filters[i];
1222         if (!strcmp(target, "all") || (filter->name && !strcmp(target, filter->name)) || !strcmp(target, filter->filter->name)) {
1223             r = avfilter_process_command(filter, cmd, arg, res, res_len, flags);
1224             if (r != AVERROR(ENOSYS)) {
1225                 if ((flags & AVFILTER_CMD_FLAG_ONE) || r < 0)
1226                     return r;
1227             }
1228         }
1229     }
1230
1231     return r;
1232 }
1233
1234 int avfilter_graph_queue_command(AVFilterGraph *graph, const char *target, const char *command, const char *arg, int flags, double ts)
1235 {
1236     int i;
1237
1238     if(!graph)
1239         return 0;
1240
1241     for (i = 0; i < graph->nb_filters; i++) {
1242         AVFilterContext *filter = graph->filters[i];
1243         if(filter && (!strcmp(target, "all") || !strcmp(target, filter->name) || !strcmp(target, filter->filter->name))){
1244             AVFilterCommand **queue = &filter->command_queue, *next;
1245             while (*queue && (*queue)->time <= ts)
1246                 queue = &(*queue)->next;
1247             next = *queue;
1248             *queue = av_mallocz(sizeof(AVFilterCommand));
1249             (*queue)->command = av_strdup(command);
1250             (*queue)->arg     = av_strdup(arg);
1251             (*queue)->time    = ts;
1252             (*queue)->flags   = flags;
1253             (*queue)->next    = next;
1254             if(flags & AVFILTER_CMD_FLAG_ONE)
1255                 return 0;
1256         }
1257     }
1258
1259     return 0;
1260 }
1261
1262 static void heap_bubble_up(AVFilterGraph *graph,
1263                            AVFilterLink *link, int index)
1264 {
1265     AVFilterLink **links = graph->sink_links;
1266
1267     while (index) {
1268         int parent = (index - 1) >> 1;
1269         if (links[parent]->current_pts >= link->current_pts)
1270             break;
1271         links[index] = links[parent];
1272         links[index]->age_index = index;
1273         index = parent;
1274     }
1275     links[index] = link;
1276     link->age_index = index;
1277 }
1278
1279 static void heap_bubble_down(AVFilterGraph *graph,
1280                              AVFilterLink *link, int index)
1281 {
1282     AVFilterLink **links = graph->sink_links;
1283
1284     while (1) {
1285         int child = 2 * index + 1;
1286         if (child >= graph->sink_links_count)
1287             break;
1288         if (child + 1 < graph->sink_links_count &&
1289             links[child + 1]->current_pts < links[child]->current_pts)
1290             child++;
1291         if (link->current_pts < links[child]->current_pts)
1292             break;
1293         links[index] = links[child];
1294         links[index]->age_index = index;
1295         index = child;
1296     }
1297     links[index] = link;
1298     link->age_index = index;
1299 }
1300
1301 void ff_avfilter_graph_update_heap(AVFilterGraph *graph, AVFilterLink *link)
1302 {
1303     heap_bubble_up  (graph, link, link->age_index);
1304     heap_bubble_down(graph, link, link->age_index);
1305 }
1306
1307
1308 int avfilter_graph_request_oldest(AVFilterGraph *graph)
1309 {
1310     while (graph->sink_links_count) {
1311         AVFilterLink *oldest = graph->sink_links[0];
1312         int r = ff_request_frame(oldest);
1313         if (r != AVERROR_EOF)
1314             return r;
1315         av_log(oldest->dst, AV_LOG_DEBUG, "EOF on sink link %s:%s.\n",
1316                oldest->dst ? oldest->dst->name : "unknown",
1317                oldest->dstpad ? oldest->dstpad->name : "unknown");
1318         /* EOF: remove the link from the heap */
1319         if (oldest->age_index < --graph->sink_links_count)
1320             heap_bubble_down(graph, graph->sink_links[graph->sink_links_count],
1321                              oldest->age_index);
1322         oldest->age_index = -1;
1323     }
1324     return AVERROR_EOF;
1325 }