3 * Copyright (c) 2008 Vitor Sessak
4 * Copyright (c) 2007 Bobby Bingham
6 * This file is part of Libav.
8 * Libav 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.
13 * Libav 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.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 #include "libavutil/avassert.h"
27 #include "libavutil/channel_layout.h"
28 #include "libavutil/common.h"
29 #include "libavutil/log.h"
31 #include "avfiltergraph.h"
35 static const AVClass filtergraph_class = {
36 .class_name = "AVFilterGraph",
37 .item_name = av_default_item_name,
38 .version = LIBAVUTIL_VERSION_INT,
41 AVFilterGraph *avfilter_graph_alloc(void)
43 AVFilterGraph *ret = av_mallocz(sizeof(AVFilterGraph));
46 ret->av_class = &filtergraph_class;
50 void avfilter_graph_free(AVFilterGraph **graph)
54 for (; (*graph)->filter_count > 0; (*graph)->filter_count--)
55 avfilter_free((*graph)->filters[(*graph)->filter_count - 1]);
56 av_freep(&(*graph)->scale_sws_opts);
57 av_freep(&(*graph)->filters);
61 int avfilter_graph_add_filter(AVFilterGraph *graph, AVFilterContext *filter)
63 AVFilterContext **filters = av_realloc(graph->filters,
64 sizeof(AVFilterContext*) * (graph->filter_count+1));
66 return AVERROR(ENOMEM);
68 graph->filters = filters;
69 graph->filters[graph->filter_count++] = filter;
74 int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
75 const char *name, const char *args, void *opaque,
76 AVFilterGraph *graph_ctx)
80 if ((ret = avfilter_open(filt_ctx, filt, name)) < 0)
82 if ((ret = avfilter_init_filter(*filt_ctx, args, opaque)) < 0)
84 if ((ret = avfilter_graph_add_filter(graph_ctx, *filt_ctx)) < 0)
90 avfilter_free(*filt_ctx);
96 * Check for the validity of graph.
98 * A graph is considered valid if all its input and output pads are
101 * @return 0 in case of success, a negative value otherwise
103 static int graph_check_validity(AVFilterGraph *graph, AVClass *log_ctx)
105 AVFilterContext *filt;
108 for (i = 0; i < graph->filter_count; i++) {
109 filt = graph->filters[i];
111 for (j = 0; j < filt->nb_inputs; j++) {
112 if (!filt->inputs[j] || !filt->inputs[j]->src) {
113 av_log(log_ctx, AV_LOG_ERROR,
114 "Input pad \"%s\" for the filter \"%s\" of type \"%s\" not connected to any source\n",
115 filt->input_pads[j].name, filt->name, filt->filter->name);
116 return AVERROR(EINVAL);
120 for (j = 0; j < filt->nb_outputs; j++) {
121 if (!filt->outputs[j] || !filt->outputs[j]->dst) {
122 av_log(log_ctx, AV_LOG_ERROR,
123 "Output pad \"%s\" for the filter \"%s\" of type \"%s\" not connected to any destination\n",
124 filt->output_pads[j].name, filt->name, filt->filter->name);
125 return AVERROR(EINVAL);
134 * Configure all the links of graphctx.
136 * @return 0 in case of success, a negative value otherwise
138 static int graph_config_links(AVFilterGraph *graph, AVClass *log_ctx)
140 AVFilterContext *filt;
143 for (i=0; i < graph->filter_count; i++) {
144 filt = graph->filters[i];
146 if (!filt->nb_outputs) {
147 if ((ret = avfilter_config_links(filt)))
155 AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name)
159 for (i = 0; i < graph->filter_count; i++)
160 if (graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
161 return graph->filters[i];
166 static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
169 int scaler_count = 0, resampler_count = 0;
171 /* ask all the sub-filters for their supported media formats */
172 for (i = 0; i < graph->filter_count; i++) {
173 if (graph->filters[i]->filter->query_formats)
174 graph->filters[i]->filter->query_formats(graph->filters[i]);
176 ff_default_query_formats(graph->filters[i]);
179 /* go through and merge as many format lists as possible */
180 for (i = 0; i < graph->filter_count; i++) {
181 AVFilterContext *filter = graph->filters[i];
183 for (j = 0; j < filter->nb_inputs; j++) {
184 AVFilterLink *link = filter->inputs[j];
185 int convert_needed = 0;
190 if (link->in_formats != link->out_formats &&
191 !ff_merge_formats(link->in_formats,
194 if (link->type == AVMEDIA_TYPE_AUDIO) {
195 if (link->in_channel_layouts != link->out_channel_layouts &&
196 !ff_merge_channel_layouts(link->in_channel_layouts,
197 link->out_channel_layouts))
199 if (link->in_samplerates != link->out_samplerates &&
200 !ff_merge_samplerates(link->in_samplerates,
201 link->out_samplerates))
205 if (convert_needed) {
206 AVFilterContext *convert;
208 AVFilterLink *inlink, *outlink;
209 char scale_args[256];
212 /* couldn't merge format lists. auto-insert conversion filter */
213 switch (link->type) {
214 case AVMEDIA_TYPE_VIDEO:
215 if (!(filter = avfilter_get_by_name("scale"))) {
216 av_log(log_ctx, AV_LOG_ERROR, "'scale' filter "
217 "not present, cannot convert pixel formats.\n");
218 return AVERROR(EINVAL);
221 snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d",
223 snprintf(scale_args, sizeof(scale_args), "0:0:%s", graph->scale_sws_opts);
224 if ((ret = avfilter_graph_create_filter(&convert, filter,
225 inst_name, scale_args, NULL,
229 case AVMEDIA_TYPE_AUDIO:
230 if (!(filter = avfilter_get_by_name("resample"))) {
231 av_log(log_ctx, AV_LOG_ERROR, "'resample' filter "
232 "not present, cannot convert audio formats.\n");
233 return AVERROR(EINVAL);
236 snprintf(inst_name, sizeof(inst_name), "auto-inserted resampler %d",
238 if ((ret = avfilter_graph_create_filter(&convert, filter,
239 inst_name, NULL, NULL, graph)) < 0)
243 return AVERROR(EINVAL);
246 if ((ret = avfilter_insert_filter(link, convert, 0, 0)) < 0)
249 convert->filter->query_formats(convert);
250 inlink = convert->inputs[0];
251 outlink = convert->outputs[0];
252 if (!ff_merge_formats( inlink->in_formats, inlink->out_formats) ||
253 !ff_merge_formats(outlink->in_formats, outlink->out_formats))
254 ret |= AVERROR(ENOSYS);
255 if (inlink->type == AVMEDIA_TYPE_AUDIO &&
256 (!ff_merge_samplerates(inlink->in_samplerates,
257 inlink->out_samplerates) ||
258 !ff_merge_channel_layouts(inlink->in_channel_layouts,
259 inlink->out_channel_layouts)))
260 ret |= AVERROR(ENOSYS);
261 if (outlink->type == AVMEDIA_TYPE_AUDIO &&
262 (!ff_merge_samplerates(outlink->in_samplerates,
263 outlink->out_samplerates) ||
264 !ff_merge_channel_layouts(outlink->in_channel_layouts,
265 outlink->out_channel_layouts)))
266 ret |= AVERROR(ENOSYS);
269 av_log(log_ctx, AV_LOG_ERROR,
270 "Impossible to convert between the formats supported by the filter "
271 "'%s' and the filter '%s'\n", link->src->name, link->dst->name);
281 static int pick_format(AVFilterLink *link)
283 if (!link || !link->in_formats)
286 link->in_formats->format_count = 1;
287 link->format = link->in_formats->formats[0];
289 if (link->type == AVMEDIA_TYPE_AUDIO) {
290 if (!link->in_samplerates->format_count) {
291 av_log(link->src, AV_LOG_ERROR, "Cannot select sample rate for"
292 " the link between filters %s and %s.\n", link->src->name,
294 return AVERROR(EINVAL);
296 link->in_samplerates->format_count = 1;
297 link->sample_rate = link->in_samplerates->formats[0];
299 if (!link->in_channel_layouts->nb_channel_layouts) {
300 av_log(link->src, AV_LOG_ERROR, "Cannot select channel layout for"
301 "the link between filters %s and %s.\n", link->src->name,
303 return AVERROR(EINVAL);
305 link->in_channel_layouts->nb_channel_layouts = 1;
306 link->channel_layout = link->in_channel_layouts->channel_layouts[0];
309 ff_formats_unref(&link->in_formats);
310 ff_formats_unref(&link->out_formats);
311 ff_formats_unref(&link->in_samplerates);
312 ff_formats_unref(&link->out_samplerates);
313 ff_channel_layouts_unref(&link->in_channel_layouts);
314 ff_channel_layouts_unref(&link->out_channel_layouts);
319 #define REDUCE_FORMATS(fmt_type, list_type, list, var, nb, add_format) \
321 for (i = 0; i < filter->nb_inputs; i++) { \
322 AVFilterLink *link = filter->inputs[i]; \
325 if (!link->out_ ## list || link->out_ ## list->nb != 1) \
327 fmt = link->out_ ## list->var[0]; \
329 for (j = 0; j < filter->nb_outputs; j++) { \
330 AVFilterLink *out_link = filter->outputs[j]; \
333 if (link->type != out_link->type || \
334 out_link->in_ ## list->nb == 1) \
336 fmts = out_link->in_ ## list; \
338 if (!out_link->in_ ## list->nb) { \
339 add_format(&out_link->in_ ##list, fmt); \
343 for (k = 0; k < out_link->in_ ## list->nb; k++) \
344 if (fmts->var[k] == fmt) { \
345 fmts->var[0] = fmt; \
354 static int reduce_formats_on_filter(AVFilterContext *filter)
356 int i, j, k, ret = 0;
358 REDUCE_FORMATS(int, AVFilterFormats, formats, formats,
359 format_count, ff_add_format);
360 REDUCE_FORMATS(int, AVFilterFormats, samplerates, formats,
361 format_count, ff_add_format);
362 REDUCE_FORMATS(uint64_t, AVFilterChannelLayouts, channel_layouts,
363 channel_layouts, nb_channel_layouts, ff_add_channel_layout);
368 static void reduce_formats(AVFilterGraph *graph)
375 for (i = 0; i < graph->filter_count; i++)
376 reduced |= reduce_formats_on_filter(graph->filters[i]);
380 static void swap_samplerates_on_filter(AVFilterContext *filter)
382 AVFilterLink *link = NULL;
386 for (i = 0; i < filter->nb_inputs; i++) {
387 link = filter->inputs[i];
389 if (link->type == AVMEDIA_TYPE_AUDIO &&
390 link->out_samplerates->format_count == 1)
393 if (i == filter->nb_inputs)
396 sample_rate = link->out_samplerates->formats[0];
398 for (i = 0; i < filter->nb_outputs; i++) {
399 AVFilterLink *outlink = filter->outputs[i];
400 int best_idx, best_diff = INT_MAX;
402 if (outlink->type != AVMEDIA_TYPE_AUDIO ||
403 outlink->in_samplerates->format_count < 2)
406 for (j = 0; j < outlink->in_samplerates->format_count; j++) {
407 int diff = abs(sample_rate - outlink->in_samplerates->formats[j]);
409 if (diff < best_diff) {
414 FFSWAP(int, outlink->in_samplerates->formats[0],
415 outlink->in_samplerates->formats[best_idx]);
419 static void swap_samplerates(AVFilterGraph *graph)
423 for (i = 0; i < graph->filter_count; i++)
424 swap_samplerates_on_filter(graph->filters[i]);
427 #define CH_CENTER_PAIR (AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER)
428 #define CH_FRONT_PAIR (AV_CH_FRONT_LEFT | AV_CH_FRONT_RIGHT)
429 #define CH_STEREO_PAIR (AV_CH_STEREO_LEFT | AV_CH_STEREO_RIGHT)
430 #define CH_WIDE_PAIR (AV_CH_WIDE_LEFT | AV_CH_WIDE_RIGHT)
431 #define CH_SIDE_PAIR (AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT)
432 #define CH_DIRECT_PAIR (AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT)
433 #define CH_BACK_PAIR (AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT)
435 /* allowable substitutions for channel pairs when comparing layouts,
436 * ordered by priority for both values */
437 static const uint64_t ch_subst[][2] = {
438 { CH_FRONT_PAIR, CH_CENTER_PAIR },
439 { CH_FRONT_PAIR, CH_WIDE_PAIR },
440 { CH_FRONT_PAIR, AV_CH_FRONT_CENTER },
441 { CH_CENTER_PAIR, CH_FRONT_PAIR },
442 { CH_CENTER_PAIR, CH_WIDE_PAIR },
443 { CH_CENTER_PAIR, AV_CH_FRONT_CENTER },
444 { CH_WIDE_PAIR, CH_FRONT_PAIR },
445 { CH_WIDE_PAIR, CH_CENTER_PAIR },
446 { CH_WIDE_PAIR, AV_CH_FRONT_CENTER },
447 { AV_CH_FRONT_CENTER, CH_FRONT_PAIR },
448 { AV_CH_FRONT_CENTER, CH_CENTER_PAIR },
449 { AV_CH_FRONT_CENTER, CH_WIDE_PAIR },
450 { CH_SIDE_PAIR, CH_DIRECT_PAIR },
451 { CH_SIDE_PAIR, CH_BACK_PAIR },
452 { CH_SIDE_PAIR, AV_CH_BACK_CENTER },
453 { CH_BACK_PAIR, CH_DIRECT_PAIR },
454 { CH_BACK_PAIR, CH_SIDE_PAIR },
455 { CH_BACK_PAIR, AV_CH_BACK_CENTER },
456 { AV_CH_BACK_CENTER, CH_BACK_PAIR },
457 { AV_CH_BACK_CENTER, CH_DIRECT_PAIR },
458 { AV_CH_BACK_CENTER, CH_SIDE_PAIR },
461 static void swap_channel_layouts_on_filter(AVFilterContext *filter)
463 AVFilterLink *link = NULL;
466 for (i = 0; i < filter->nb_inputs; i++) {
467 link = filter->inputs[i];
469 if (link->type == AVMEDIA_TYPE_AUDIO &&
470 link->out_channel_layouts->nb_channel_layouts == 1)
473 if (i == filter->nb_inputs)
476 for (i = 0; i < filter->nb_outputs; i++) {
477 AVFilterLink *outlink = filter->outputs[i];
478 int best_idx = -1, best_score = INT_MIN, best_count_diff = INT_MAX;
480 if (outlink->type != AVMEDIA_TYPE_AUDIO ||
481 outlink->in_channel_layouts->nb_channel_layouts < 2)
484 for (j = 0; j < outlink->in_channel_layouts->nb_channel_layouts; j++) {
485 uint64_t in_chlayout = link->out_channel_layouts->channel_layouts[0];
486 uint64_t out_chlayout = outlink->in_channel_layouts->channel_layouts[j];
487 int in_channels = av_get_channel_layout_nb_channels(in_chlayout);
488 int out_channels = av_get_channel_layout_nb_channels(out_chlayout);
489 int count_diff = out_channels - in_channels;
490 int matched_channels, extra_channels;
493 /* channel substitution */
494 for (k = 0; k < FF_ARRAY_ELEMS(ch_subst); k++) {
495 uint64_t cmp0 = ch_subst[k][0];
496 uint64_t cmp1 = ch_subst[k][1];
497 if (( in_chlayout & cmp0) && (!(out_chlayout & cmp0)) &&
498 (out_chlayout & cmp1) && (!( in_chlayout & cmp1))) {
499 in_chlayout &= ~cmp0;
500 out_chlayout &= ~cmp1;
501 /* add score for channel match, minus a deduction for
502 having to do the substitution */
503 score += 10 * av_get_channel_layout_nb_channels(cmp1) - 2;
507 /* no penalty for LFE channel mismatch */
508 if ( (in_chlayout & AV_CH_LOW_FREQUENCY) &&
509 (out_chlayout & AV_CH_LOW_FREQUENCY))
511 in_chlayout &= ~AV_CH_LOW_FREQUENCY;
512 out_chlayout &= ~AV_CH_LOW_FREQUENCY;
514 matched_channels = av_get_channel_layout_nb_channels(in_chlayout &
516 extra_channels = av_get_channel_layout_nb_channels(out_chlayout &
518 score += 10 * matched_channels - 5 * extra_channels;
520 if (score > best_score ||
521 (count_diff < best_count_diff && score == best_score)) {
524 best_count_diff = count_diff;
527 av_assert0(best_idx >= 0);
528 FFSWAP(uint64_t, outlink->in_channel_layouts->channel_layouts[0],
529 outlink->in_channel_layouts->channel_layouts[best_idx]);
534 static void swap_channel_layouts(AVFilterGraph *graph)
538 for (i = 0; i < graph->filter_count; i++)
539 swap_channel_layouts_on_filter(graph->filters[i]);
542 static void swap_sample_fmts_on_filter(AVFilterContext *filter)
544 AVFilterLink *link = NULL;
548 for (i = 0; i < filter->nb_inputs; i++) {
549 link = filter->inputs[i];
551 if (link->type == AVMEDIA_TYPE_AUDIO &&
552 link->out_formats->format_count == 1)
555 if (i == filter->nb_inputs)
558 format = link->out_formats->formats[0];
559 bps = av_get_bytes_per_sample(format);
561 for (i = 0; i < filter->nb_outputs; i++) {
562 AVFilterLink *outlink = filter->outputs[i];
563 int best_idx = -1, best_score = INT_MIN;
565 if (outlink->type != AVMEDIA_TYPE_AUDIO ||
566 outlink->in_formats->format_count < 2)
569 for (j = 0; j < outlink->in_formats->format_count; j++) {
570 int out_format = outlink->in_formats->formats[j];
571 int out_bps = av_get_bytes_per_sample(out_format);
574 if (av_get_packed_sample_fmt(out_format) == format ||
575 av_get_planar_sample_fmt(out_format) == format) {
580 /* for s32 and float prefer double to prevent loss of information */
581 if (bps == 4 && out_bps == 8) {
586 /* prefer closest higher or equal bps */
587 score = -abs(out_bps - bps);
591 if (score > best_score) {
596 av_assert0(best_idx >= 0);
597 FFSWAP(int, outlink->in_formats->formats[0],
598 outlink->in_formats->formats[best_idx]);
602 static void swap_sample_fmts(AVFilterGraph *graph)
606 for (i = 0; i < graph->filter_count; i++)
607 swap_sample_fmts_on_filter(graph->filters[i]);
611 static int pick_formats(AVFilterGraph *graph)
615 for (i = 0; i < graph->filter_count; i++) {
616 AVFilterContext *filter = graph->filters[i];
618 for (j = 0; j < filter->nb_inputs; j++)
619 if ((ret = pick_format(filter->inputs[j])) < 0)
621 for (j = 0; j < filter->nb_outputs; j++)
622 if ((ret = pick_format(filter->outputs[j])) < 0)
629 * Configure the formats of all the links in the graph.
631 static int graph_config_formats(AVFilterGraph *graph, AVClass *log_ctx)
635 /* find supported formats from sub-filters, and merge along links */
636 if ((ret = query_formats(graph, log_ctx)) < 0)
639 /* Once everything is merged, it's possible that we'll still have
640 * multiple valid media format choices. We try to minimize the amount
641 * of format conversion inside filters */
642 reduce_formats(graph);
644 /* for audio filters, ensure the best format, sample rate and channel layout
646 swap_sample_fmts(graph);
647 swap_samplerates(graph);
648 swap_channel_layouts(graph);
650 if ((ret = pick_formats(graph)) < 0)
656 static int graph_insert_fifos(AVFilterGraph *graph, AVClass *log_ctx)
662 for (i = 0; i < graph->filter_count; i++) {
663 f = graph->filters[i];
665 for (j = 0; j < f->nb_inputs; j++) {
666 AVFilterLink *link = f->inputs[j];
667 AVFilterContext *fifo_ctx;
671 if (!link->dstpad->needs_fifo)
674 fifo = f->inputs[j]->type == AVMEDIA_TYPE_VIDEO ?
675 avfilter_get_by_name("fifo") :
676 avfilter_get_by_name("afifo");
678 snprintf(name, sizeof(name), "auto-inserted fifo %d", fifo_count++);
680 ret = avfilter_graph_create_filter(&fifo_ctx, fifo, name, NULL,
685 ret = avfilter_insert_filter(link, fifo_ctx, 0, 0);
694 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
698 if ((ret = graph_check_validity(graphctx, log_ctx)))
700 if ((ret = graph_insert_fifos(graphctx, log_ctx)) < 0)
702 if ((ret = graph_config_formats(graphctx, log_ctx)))
704 if ((ret = graph_config_links(graphctx, log_ctx)))