lavfi: allow building without swscale.
[libav.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 Libav.
7 *
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.
12 *
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.
17 *
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
21 */
22
23 #include <ctype.h>
24 #include <string.h>
25
26 #include "avfilter.h"
27 #include "avfiltergraph.h"
28 #include "formats.h"
29 #include "internal.h"
30
31 #include "libavutil/audioconvert.h"
32 #include "libavutil/log.h"
33
34 static const AVClass filtergraph_class = {
35 .class_name = "AVFilterGraph",
36 .item_name = av_default_item_name,
37 .version = LIBAVUTIL_VERSION_INT,
38 };
39
40 AVFilterGraph *avfilter_graph_alloc(void)
41 {
42 AVFilterGraph *ret = av_mallocz(sizeof(AVFilterGraph));
43 if (!ret)
44 return NULL;
45 #if FF_API_GRAPH_AVCLASS
46 ret->av_class = &filtergraph_class;
47 #endif
48 return ret;
49 }
50
51 void avfilter_graph_free(AVFilterGraph **graph)
52 {
53 if (!*graph)
54 return;
55 for (; (*graph)->filter_count > 0; (*graph)->filter_count--)
56 avfilter_free((*graph)->filters[(*graph)->filter_count - 1]);
57 av_freep(&(*graph)->scale_sws_opts);
58 av_freep(&(*graph)->filters);
59 av_freep(graph);
60 }
61
62 int avfilter_graph_add_filter(AVFilterGraph *graph, AVFilterContext *filter)
63 {
64 AVFilterContext **filters = av_realloc(graph->filters,
65 sizeof(AVFilterContext*) * (graph->filter_count+1));
66 if (!filters)
67 return AVERROR(ENOMEM);
68
69 graph->filters = filters;
70 graph->filters[graph->filter_count++] = filter;
71
72 return 0;
73 }
74
75 int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
76 const char *name, const char *args, void *opaque,
77 AVFilterGraph *graph_ctx)
78 {
79 int ret;
80
81 if ((ret = avfilter_open(filt_ctx, filt, name)) < 0)
82 goto fail;
83 if ((ret = avfilter_init_filter(*filt_ctx, args, opaque)) < 0)
84 goto fail;
85 if ((ret = avfilter_graph_add_filter(graph_ctx, *filt_ctx)) < 0)
86 goto fail;
87 return 0;
88
89 fail:
90 if (*filt_ctx)
91 avfilter_free(*filt_ctx);
92 *filt_ctx = NULL;
93 return ret;
94 }
95
96 /**
97 * Check for the validity of graph.
98 *
99 * A graph is considered valid if all its input and output pads are
100 * connected.
101 *
102 * @return 0 in case of success, a negative value otherwise
103 */
104 static int graph_check_validity(AVFilterGraph *graph, AVClass *log_ctx)
105 {
106 AVFilterContext *filt;
107 int i, j;
108
109 for (i = 0; i < graph->filter_count; i++) {
110 filt = graph->filters[i];
111
112 for (j = 0; j < filt->nb_inputs; j++) {
113 if (!filt->inputs[j] || !filt->inputs[j]->src) {
114 av_log(log_ctx, AV_LOG_ERROR,
115 "Input pad \"%s\" for the filter \"%s\" of type \"%s\" not connected to any source\n",
116 filt->input_pads[j].name, filt->name, filt->filter->name);
117 return AVERROR(EINVAL);
118 }
119 }
120
121 for (j = 0; j < filt->nb_outputs; j++) {
122 if (!filt->outputs[j] || !filt->outputs[j]->dst) {
123 av_log(log_ctx, AV_LOG_ERROR,
124 "Output pad \"%s\" for the filter \"%s\" of type \"%s\" not connected to any destination\n",
125 filt->output_pads[j].name, filt->name, filt->filter->name);
126 return AVERROR(EINVAL);
127 }
128 }
129 }
130
131 return 0;
132 }
133
134 /**
135 * Configure all the links of graphctx.
136 *
137 * @return 0 in case of success, a negative value otherwise
138 */
139 static int graph_config_links(AVFilterGraph *graph, AVClass *log_ctx)
140 {
141 AVFilterContext *filt;
142 int i, ret;
143
144 for (i=0; i < graph->filter_count; i++) {
145 filt = graph->filters[i];
146
147 if (!filt->nb_outputs) {
148 if ((ret = avfilter_config_links(filt)))
149 return ret;
150 }
151 }
152
153 return 0;
154 }
155
156 AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name)
157 {
158 int i;
159
160 for (i = 0; i < graph->filter_count; i++)
161 if (graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
162 return graph->filters[i];
163
164 return NULL;
165 }
166
167 static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
168 {
169 int i, j, ret;
170 int scaler_count = 0, resampler_count = 0;
171
172 /* ask all the sub-filters for their supported media formats */
173 for (i = 0; i < graph->filter_count; i++) {
174 if (graph->filters[i]->filter->query_formats)
175 graph->filters[i]->filter->query_formats(graph->filters[i]);
176 else
177 ff_default_query_formats(graph->filters[i]);
178 }
179
180 /* go through and merge as many format lists as possible */
181 for (i = 0; i < graph->filter_count; i++) {
182 AVFilterContext *filter = graph->filters[i];
183
184 for (j = 0; j < filter->nb_inputs; j++) {
185 AVFilterLink *link = filter->inputs[j];
186 int convert_needed = 0;
187
188 if (!link)
189 continue;
190
191 if (link->in_formats != link->out_formats &&
192 !ff_merge_formats(link->in_formats,
193 link->out_formats))
194 convert_needed = 1;
195 if (link->type == AVMEDIA_TYPE_AUDIO) {
196 if (link->in_channel_layouts != link->out_channel_layouts &&
197 !ff_merge_channel_layouts(link->in_channel_layouts,
198 link->out_channel_layouts))
199 convert_needed = 1;
200 if (link->in_samplerates != link->out_samplerates &&
201 !ff_merge_samplerates(link->in_samplerates,
202 link->out_samplerates))
203 convert_needed = 1;
204 }
205
206 if (convert_needed) {
207 AVFilterContext *convert;
208 AVFilter *filter;
209 AVFilterLink *inlink, *outlink;
210 char scale_args[256];
211 char inst_name[30];
212
213 /* couldn't merge format lists. auto-insert conversion filter */
214 switch (link->type) {
215 case AVMEDIA_TYPE_VIDEO:
216 if (!(filter = avfilter_get_by_name("scale"))) {
217 av_log(log_ctx, AV_LOG_ERROR, "'scale' filter "
218 "not present, cannot convert pixel formats.\n");
219 return AVERROR(EINVAL);
220 }
221
222 snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d",
223 scaler_count++);
224 snprintf(scale_args, sizeof(scale_args), "0:0:%s", graph->scale_sws_opts);
225 if ((ret = avfilter_graph_create_filter(&convert, filter,
226 inst_name, scale_args, NULL,
227 graph)) < 0)
228 return ret;
229 break;
230 case AVMEDIA_TYPE_AUDIO:
231 if (!(filter = avfilter_get_by_name("resample"))) {
232 av_log(log_ctx, AV_LOG_ERROR, "'resample' filter "
233 "not present, cannot convert audio formats.\n");
234 return AVERROR(EINVAL);
235 }
236
237 snprintf(inst_name, sizeof(inst_name), "auto-inserted resampler %d",
238 resampler_count++);
239 if ((ret = avfilter_graph_create_filter(&convert,
240 avfilter_get_by_name("resample"),
241 inst_name, NULL, NULL, graph)) < 0)
242 return ret;
243 break;
244 default:
245 return AVERROR(EINVAL);
246 }
247
248 if ((ret = avfilter_insert_filter(link, convert, 0, 0)) < 0)
249 return ret;
250
251 convert->filter->query_formats(convert);
252 inlink = convert->inputs[0];
253 outlink = convert->outputs[0];
254 if (!ff_merge_formats( inlink->in_formats, inlink->out_formats) ||
255 !ff_merge_formats(outlink->in_formats, outlink->out_formats))
256 ret |= AVERROR(ENOSYS);
257 if (inlink->type == AVMEDIA_TYPE_AUDIO &&
258 (!ff_merge_samplerates(inlink->in_samplerates,
259 inlink->out_samplerates) ||
260 !ff_merge_channel_layouts(inlink->in_channel_layouts,
261 inlink->out_channel_layouts)))
262 ret |= AVERROR(ENOSYS);
263 if (outlink->type == AVMEDIA_TYPE_AUDIO &&
264 (!ff_merge_samplerates(outlink->in_samplerates,
265 outlink->out_samplerates) ||
266 !ff_merge_channel_layouts(outlink->in_channel_layouts,
267 outlink->out_channel_layouts)))
268 ret |= AVERROR(ENOSYS);
269
270 if (ret < 0) {
271 av_log(log_ctx, AV_LOG_ERROR,
272 "Impossible to convert between the formats supported by the filter "
273 "'%s' and the filter '%s'\n", link->src->name, link->dst->name);
274 return ret;
275 }
276 }
277 }
278 }
279
280 return 0;
281 }
282
283 static int pick_format(AVFilterLink *link)
284 {
285 if (!link || !link->in_formats)
286 return 0;
287
288 link->in_formats->format_count = 1;
289 link->format = link->in_formats->formats[0];
290
291 if (link->type == AVMEDIA_TYPE_AUDIO) {
292 if (!link->in_samplerates->format_count) {
293 av_log(link->src, AV_LOG_ERROR, "Cannot select sample rate for"
294 " the link between filters %s and %s.\n", link->src->name,
295 link->dst->name);
296 return AVERROR(EINVAL);
297 }
298 link->in_samplerates->format_count = 1;
299 link->sample_rate = link->in_samplerates->formats[0];
300
301 if (!link->in_channel_layouts->nb_channel_layouts) {
302 av_log(link->src, AV_LOG_ERROR, "Cannot select channel layout for"
303 "the link between filters %s and %s.\n", link->src->name,
304 link->dst->name);
305 return AVERROR(EINVAL);
306 }
307 link->in_channel_layouts->nb_channel_layouts = 1;
308 link->channel_layout = link->in_channel_layouts->channel_layouts[0];
309 }
310
311 ff_formats_unref(&link->in_formats);
312 ff_formats_unref(&link->out_formats);
313 ff_formats_unref(&link->in_samplerates);
314 ff_formats_unref(&link->out_samplerates);
315 ff_channel_layouts_unref(&link->in_channel_layouts);
316 ff_channel_layouts_unref(&link->out_channel_layouts);
317
318 return 0;
319 }
320
321 #define REDUCE_FORMATS(fmt_type, list_type, list, var, nb, add_format) \
322 do { \
323 for (i = 0; i < filter->nb_inputs; i++) { \
324 AVFilterLink *link = filter->inputs[i]; \
325 fmt_type fmt; \
326 \
327 if (!link->out_ ## list || link->out_ ## list->nb != 1) \
328 continue; \
329 fmt = link->out_ ## list->var[0]; \
330 \
331 for (j = 0; j < filter->nb_outputs; j++) { \
332 AVFilterLink *out_link = filter->outputs[j]; \
333 list_type *fmts; \
334 \
335 if (link->type != out_link->type || \
336 out_link->in_ ## list->nb == 1) \
337 continue; \
338 fmts = out_link->in_ ## list; \
339 \
340 if (!out_link->in_ ## list->nb) { \
341 add_format(&out_link->in_ ##list, fmt); \
342 break; \
343 } \
344 \
345 for (k = 0; k < out_link->in_ ## list->nb; k++) \
346 if (fmts->var[k] == fmt) { \
347 fmts->var[0] = fmt; \
348 fmts->nb = 1; \
349 ret = 1; \
350 break; \
351 } \
352 } \
353 } \
354 } while (0)
355
356 static int reduce_formats_on_filter(AVFilterContext *filter)
357 {
358 int i, j, k, ret = 0;
359
360 REDUCE_FORMATS(int, AVFilterFormats, formats, formats,
361 format_count, ff_add_format);
362 REDUCE_FORMATS(int, AVFilterFormats, samplerates, formats,
363 format_count, ff_add_format);
364 REDUCE_FORMATS(uint64_t, AVFilterChannelLayouts, channel_layouts,
365 channel_layouts, nb_channel_layouts, ff_add_channel_layout);
366
367 return ret;
368 }
369
370 static void reduce_formats(AVFilterGraph *graph)
371 {
372 int i, reduced;
373
374 do {
375 reduced = 0;
376
377 for (i = 0; i < graph->filter_count; i++)
378 reduced |= reduce_formats_on_filter(graph->filters[i]);
379 } while (reduced);
380 }
381
382 static void swap_samplerates_on_filter(AVFilterContext *filter)
383 {
384 AVFilterLink *link = NULL;
385 int sample_rate;
386 int i, j;
387
388 for (i = 0; i < filter->nb_inputs; i++) {
389 link = filter->inputs[i];
390
391 if (link->type == AVMEDIA_TYPE_AUDIO &&
392 link->out_samplerates->format_count == 1)
393 break;
394 }
395 if (i == filter->nb_inputs)
396 return;
397
398 sample_rate = link->out_samplerates->formats[0];
399
400 for (i = 0; i < filter->nb_outputs; i++) {
401 AVFilterLink *outlink = filter->outputs[i];
402 int best_idx, best_diff = INT_MAX;
403
404 if (outlink->type != AVMEDIA_TYPE_AUDIO ||
405 outlink->in_samplerates->format_count < 2)
406 continue;
407
408 for (j = 0; j < outlink->in_samplerates->format_count; j++) {
409 int diff = abs(sample_rate - outlink->in_samplerates->formats[j]);
410
411 if (diff < best_diff) {
412 best_diff = diff;
413 best_idx = j;
414 }
415 }
416 FFSWAP(int, outlink->in_samplerates->formats[0],
417 outlink->in_samplerates->formats[best_idx]);
418 }
419 }
420
421 static void swap_samplerates(AVFilterGraph *graph)
422 {
423 int i;
424
425 for (i = 0; i < graph->filter_count; i++)
426 swap_samplerates_on_filter(graph->filters[i]);
427 }
428
429 static void swap_channel_layouts_on_filter(AVFilterContext *filter)
430 {
431 AVFilterLink *link = NULL;
432 uint64_t chlayout;
433 int i, j;
434
435 for (i = 0; i < filter->nb_inputs; i++) {
436 link = filter->inputs[i];
437
438 if (link->type == AVMEDIA_TYPE_AUDIO &&
439 link->out_channel_layouts->nb_channel_layouts == 1)
440 break;
441 }
442 if (i == filter->nb_inputs)
443 return;
444
445 chlayout = link->out_channel_layouts->channel_layouts[0];
446
447 for (i = 0; i < filter->nb_outputs; i++) {
448 AVFilterLink *outlink = filter->outputs[i];
449 int best_idx, best_score = INT_MIN;
450
451 if (outlink->type != AVMEDIA_TYPE_AUDIO ||
452 outlink->in_channel_layouts->nb_channel_layouts < 2)
453 continue;
454
455 for (j = 0; j < outlink->in_channel_layouts->nb_channel_layouts; j++) {
456 uint64_t out_chlayout = outlink->in_channel_layouts->channel_layouts[j];
457 int matched_channels = av_get_channel_layout_nb_channels(chlayout &
458 out_chlayout);
459 int extra_channels = av_get_channel_layout_nb_channels(out_chlayout &
460 (~chlayout));
461 int score = matched_channels - extra_channels;
462
463 if (score > best_score) {
464 best_score = score;
465 best_idx = j;
466 }
467 }
468 FFSWAP(uint64_t, outlink->in_channel_layouts->channel_layouts[0],
469 outlink->in_channel_layouts->channel_layouts[best_idx]);
470 }
471
472 }
473
474 static void swap_channel_layouts(AVFilterGraph *graph)
475 {
476 int i;
477
478 for (i = 0; i < graph->filter_count; i++)
479 swap_channel_layouts_on_filter(graph->filters[i]);
480 }
481
482 static void swap_sample_fmts_on_filter(AVFilterContext *filter)
483 {
484 AVFilterLink *link = NULL;
485 int format, bps;
486 int i, j;
487
488 for (i = 0; i < filter->nb_inputs; i++) {
489 link = filter->inputs[i];
490
491 if (link->type == AVMEDIA_TYPE_AUDIO &&
492 link->out_formats->format_count == 1)
493 break;
494 }
495 if (i == filter->nb_inputs)
496 return;
497
498 format = link->out_formats->formats[0];
499 bps = av_get_bytes_per_sample(format);
500
501 for (i = 0; i < filter->nb_outputs; i++) {
502 AVFilterLink *outlink = filter->outputs[i];
503 int best_idx, best_score = INT_MIN;
504
505 if (outlink->type != AVMEDIA_TYPE_AUDIO ||
506 outlink->in_formats->format_count < 2)
507 continue;
508
509 for (j = 0; j < outlink->in_formats->format_count; j++) {
510 int out_format = outlink->in_formats->formats[j];
511 int out_bps = av_get_bytes_per_sample(out_format);
512 int score;
513
514 if (av_get_packed_sample_fmt(out_format) == format ||
515 av_get_planar_sample_fmt(out_format) == format) {
516 best_idx = j;
517 break;
518 }
519
520 /* for s32 and float prefer double to prevent loss of information */
521 if (bps == 4 && out_bps == 8) {
522 best_idx = j;
523 break;
524 }
525
526 /* prefer closest higher or equal bps */
527 score = -abs(out_bps - bps);
528 if (out_bps >= bps)
529 score += INT_MAX/2;
530
531 if (score > best_score) {
532 best_score = score;
533 best_idx = j;
534 }
535 }
536 FFSWAP(int, outlink->in_formats->formats[0],
537 outlink->in_formats->formats[best_idx]);
538 }
539 }
540
541 static void swap_sample_fmts(AVFilterGraph *graph)
542 {
543 int i;
544
545 for (i = 0; i < graph->filter_count; i++)
546 swap_sample_fmts_on_filter(graph->filters[i]);
547
548 }
549
550 static int pick_formats(AVFilterGraph *graph)
551 {
552 int i, j, ret;
553
554 for (i = 0; i < graph->filter_count; i++) {
555 AVFilterContext *filter = graph->filters[i];
556
557 for (j = 0; j < filter->nb_inputs; j++)
558 if ((ret = pick_format(filter->inputs[j])) < 0)
559 return ret;
560 for (j = 0; j < filter->nb_outputs; j++)
561 if ((ret = pick_format(filter->outputs[j])) < 0)
562 return ret;
563 }
564 return 0;
565 }
566
567 /**
568 * Configure the formats of all the links in the graph.
569 */
570 static int graph_config_formats(AVFilterGraph *graph, AVClass *log_ctx)
571 {
572 int ret;
573
574 /* find supported formats from sub-filters, and merge along links */
575 if ((ret = query_formats(graph, log_ctx)) < 0)
576 return ret;
577
578 /* Once everything is merged, it's possible that we'll still have
579 * multiple valid media format choices. We try to minimize the amount
580 * of format conversion inside filters */
581 reduce_formats(graph);
582
583 /* for audio filters, ensure the best format, sample rate and channel layout
584 * is selected */
585 swap_sample_fmts(graph);
586 swap_samplerates(graph);
587 swap_channel_layouts(graph);
588
589 if ((ret = pick_formats(graph)) < 0)
590 return ret;
591
592 return 0;
593 }
594
595 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
596 {
597 int ret;
598
599 if ((ret = graph_check_validity(graphctx, log_ctx)))
600 return ret;
601 if ((ret = graph_config_formats(graphctx, log_ctx)))
602 return ret;
603 if ((ret = graph_config_links(graphctx, log_ctx)))
604 return ret;
605
606 return 0;
607 }