lavc/mjpegenc_common: Remove an unused variable.
[ffmpeg.git] / ffmpeg_filter.c
1 /*
2  * ffmpeg filter configuration
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20
21 #include <stdint.h>
22
23 #include "ffmpeg.h"
24
25 #include "libavfilter/avfilter.h"
26 #include "libavfilter/buffersink.h"
27 #include "libavfilter/buffersrc.h"
28
29 #include "libavresample/avresample.h"
30
31 #include "libavutil/avassert.h"
32 #include "libavutil/avstring.h"
33 #include "libavutil/bprint.h"
34 #include "libavutil/channel_layout.h"
35 #include "libavutil/display.h"
36 #include "libavutil/opt.h"
37 #include "libavutil/pixdesc.h"
38 #include "libavutil/pixfmt.h"
39 #include "libavutil/imgutils.h"
40 #include "libavutil/samplefmt.h"
41
42 static const enum AVPixelFormat *get_compliance_unofficial_pix_fmts(enum AVCodecID codec_id, const enum AVPixelFormat default_formats[])
43 {
44     static const enum AVPixelFormat mjpeg_formats[] =
45         { AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P,
46           AV_PIX_FMT_YUV420P,  AV_PIX_FMT_YUV422P,  AV_PIX_FMT_YUV444P,
47           AV_PIX_FMT_NONE };
48     static const enum AVPixelFormat ljpeg_formats[] =
49         { AV_PIX_FMT_BGR24   , AV_PIX_FMT_BGRA    , AV_PIX_FMT_BGR0,
50           AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,
51           AV_PIX_FMT_YUV420P , AV_PIX_FMT_YUV444P , AV_PIX_FMT_YUV422P,
52           AV_PIX_FMT_NONE};
53
54     if (codec_id == AV_CODEC_ID_MJPEG) {
55         return mjpeg_formats;
56     } else if (codec_id == AV_CODEC_ID_LJPEG) {
57         return ljpeg_formats;
58     } else {
59         return default_formats;
60     }
61 }
62
63 enum AVPixelFormat choose_pixel_fmt(AVStream *st, AVCodecContext *enc_ctx, AVCodec *codec, enum AVPixelFormat target)
64 {
65     if (codec && codec->pix_fmts) {
66         const enum AVPixelFormat *p = codec->pix_fmts;
67         const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(target);
68         int has_alpha = desc ? desc->nb_components % 2 == 0 : 0;
69         enum AVPixelFormat best= AV_PIX_FMT_NONE;
70
71         if (enc_ctx->strict_std_compliance <= FF_COMPLIANCE_UNOFFICIAL) {
72             p = get_compliance_unofficial_pix_fmts(enc_ctx->codec_id, p);
73         }
74         for (; *p != AV_PIX_FMT_NONE; p++) {
75             best= avcodec_find_best_pix_fmt_of_2(best, *p, target, has_alpha, NULL);
76             if (*p == target)
77                 break;
78         }
79         if (*p == AV_PIX_FMT_NONE) {
80             if (target != AV_PIX_FMT_NONE)
81                 av_log(NULL, AV_LOG_WARNING,
82                        "Incompatible pixel format '%s' for codec '%s', auto-selecting format '%s'\n",
83                        av_get_pix_fmt_name(target),
84                        codec->name,
85                        av_get_pix_fmt_name(best));
86             return best;
87         }
88     }
89     return target;
90 }
91
92 void choose_sample_fmt(AVStream *st, AVCodec *codec)
93 {
94     if (codec && codec->sample_fmts) {
95         const enum AVSampleFormat *p = codec->sample_fmts;
96         for (; *p != -1; p++) {
97             if (*p == st->codecpar->format)
98                 break;
99         }
100         if (*p == -1) {
101             if((codec->capabilities & AV_CODEC_CAP_LOSSLESS) && av_get_sample_fmt_name(st->codecpar->format) > av_get_sample_fmt_name(codec->sample_fmts[0]))
102                 av_log(NULL, AV_LOG_ERROR, "Conversion will not be lossless.\n");
103             if(av_get_sample_fmt_name(st->codecpar->format))
104             av_log(NULL, AV_LOG_WARNING,
105                    "Incompatible sample format '%s' for codec '%s', auto-selecting format '%s'\n",
106                    av_get_sample_fmt_name(st->codecpar->format),
107                    codec->name,
108                    av_get_sample_fmt_name(codec->sample_fmts[0]));
109             st->codecpar->format = codec->sample_fmts[0];
110         }
111     }
112 }
113
114 static char *choose_pix_fmts(OutputFilter *ofilter)
115 {
116     OutputStream *ost = ofilter->ost;
117     AVDictionaryEntry *strict_dict = av_dict_get(ost->encoder_opts, "strict", NULL, 0);
118     if (strict_dict)
119         // used by choose_pixel_fmt() and below
120         av_opt_set(ost->enc_ctx, "strict", strict_dict->value, 0);
121
122      if (ost->keep_pix_fmt) {
123         avfilter_graph_set_auto_convert(ofilter->graph->graph,
124                                             AVFILTER_AUTO_CONVERT_NONE);
125         if (ost->enc_ctx->pix_fmt == AV_PIX_FMT_NONE)
126             return NULL;
127         return av_strdup(av_get_pix_fmt_name(ost->enc_ctx->pix_fmt));
128     }
129     if (ost->enc_ctx->pix_fmt != AV_PIX_FMT_NONE) {
130         return av_strdup(av_get_pix_fmt_name(choose_pixel_fmt(ost->st, ost->enc_ctx, ost->enc, ost->enc_ctx->pix_fmt)));
131     } else if (ost->enc && ost->enc->pix_fmts) {
132         const enum AVPixelFormat *p;
133         AVIOContext *s = NULL;
134         uint8_t *ret;
135         int len;
136
137         if (avio_open_dyn_buf(&s) < 0)
138             exit_program(1);
139
140         p = ost->enc->pix_fmts;
141         if (ost->enc_ctx->strict_std_compliance <= FF_COMPLIANCE_UNOFFICIAL) {
142             p = get_compliance_unofficial_pix_fmts(ost->enc_ctx->codec_id, p);
143         }
144
145         for (; *p != AV_PIX_FMT_NONE; p++) {
146             const char *name = av_get_pix_fmt_name(*p);
147             avio_printf(s, "%s|", name);
148         }
149         len = avio_close_dyn_buf(s, &ret);
150         ret[len - 1] = 0;
151         return ret;
152     } else
153         return NULL;
154 }
155
156 /* Define a function for building a string containing a list of
157  * allowed formats. */
158 #define DEF_CHOOSE_FORMAT(suffix, type, var, supported_list, none, get_name)   \
159 static char *choose_ ## suffix (OutputFilter *ofilter)                         \
160 {                                                                              \
161     if (ofilter->var != none) {                                                \
162         get_name(ofilter->var);                                                \
163         return av_strdup(name);                                                \
164     } else if (ofilter->supported_list) {                                      \
165         const type *p;                                                         \
166         AVIOContext *s = NULL;                                                 \
167         uint8_t *ret;                                                          \
168         int len;                                                               \
169                                                                                \
170         if (avio_open_dyn_buf(&s) < 0)                                         \
171             exit_program(1);                                                           \
172                                                                                \
173         for (p = ofilter->supported_list; *p != none; p++) {                   \
174             get_name(*p);                                                      \
175             avio_printf(s, "%s|", name);                                       \
176         }                                                                      \
177         len = avio_close_dyn_buf(s, &ret);                                     \
178         ret[len - 1] = 0;                                                      \
179         return ret;                                                            \
180     } else                                                                     \
181         return NULL;                                                           \
182 }
183
184 //DEF_CHOOSE_FORMAT(pix_fmts, enum AVPixelFormat, format, formats, AV_PIX_FMT_NONE,
185 //                  GET_PIX_FMT_NAME)
186
187 DEF_CHOOSE_FORMAT(sample_fmts, enum AVSampleFormat, format, formats,
188                   AV_SAMPLE_FMT_NONE, GET_SAMPLE_FMT_NAME)
189
190 DEF_CHOOSE_FORMAT(sample_rates, int, sample_rate, sample_rates, 0,
191                   GET_SAMPLE_RATE_NAME)
192
193 DEF_CHOOSE_FORMAT(channel_layouts, uint64_t, channel_layout, channel_layouts, 0,
194                   GET_CH_LAYOUT_NAME)
195
196 int init_simple_filtergraph(InputStream *ist, OutputStream *ost)
197 {
198     FilterGraph *fg = av_mallocz(sizeof(*fg));
199
200     if (!fg)
201         exit_program(1);
202     fg->index = nb_filtergraphs;
203
204     GROW_ARRAY(fg->outputs, fg->nb_outputs);
205     if (!(fg->outputs[0] = av_mallocz(sizeof(*fg->outputs[0]))))
206         exit_program(1);
207     fg->outputs[0]->ost   = ost;
208     fg->outputs[0]->graph = fg;
209     fg->outputs[0]->format = -1;
210
211     ost->filter = fg->outputs[0];
212
213     GROW_ARRAY(fg->inputs, fg->nb_inputs);
214     if (!(fg->inputs[0] = av_mallocz(sizeof(*fg->inputs[0]))))
215         exit_program(1);
216     fg->inputs[0]->ist   = ist;
217     fg->inputs[0]->graph = fg;
218     fg->inputs[0]->format = -1;
219
220     GROW_ARRAY(ist->filters, ist->nb_filters);
221     ist->filters[ist->nb_filters - 1] = fg->inputs[0];
222
223     GROW_ARRAY(filtergraphs, nb_filtergraphs);
224     filtergraphs[nb_filtergraphs - 1] = fg;
225
226     return 0;
227 }
228
229 static void init_input_filter(FilterGraph *fg, AVFilterInOut *in)
230 {
231     InputStream *ist = NULL;
232     enum AVMediaType type = avfilter_pad_get_type(in->filter_ctx->input_pads, in->pad_idx);
233     int i;
234
235     // TODO: support other filter types
236     if (type != AVMEDIA_TYPE_VIDEO && type != AVMEDIA_TYPE_AUDIO) {
237         av_log(NULL, AV_LOG_FATAL, "Only video and audio filters supported "
238                "currently.\n");
239         exit_program(1);
240     }
241
242     if (in->name) {
243         AVFormatContext *s;
244         AVStream       *st = NULL;
245         char *p;
246         int file_idx = strtol(in->name, &p, 0);
247
248         if (file_idx < 0 || file_idx >= nb_input_files) {
249             av_log(NULL, AV_LOG_FATAL, "Invalid file index %d in filtergraph description %s.\n",
250                    file_idx, fg->graph_desc);
251             exit_program(1);
252         }
253         s = input_files[file_idx]->ctx;
254
255         for (i = 0; i < s->nb_streams; i++) {
256             enum AVMediaType stream_type = s->streams[i]->codecpar->codec_type;
257             if (stream_type != type &&
258                 !(stream_type == AVMEDIA_TYPE_SUBTITLE &&
259                   type == AVMEDIA_TYPE_VIDEO /* sub2video hack */))
260                 continue;
261             if (check_stream_specifier(s, s->streams[i], *p == ':' ? p + 1 : p) == 1) {
262                 st = s->streams[i];
263                 break;
264             }
265         }
266         if (!st) {
267             av_log(NULL, AV_LOG_FATAL, "Stream specifier '%s' in filtergraph description %s "
268                    "matches no streams.\n", p, fg->graph_desc);
269             exit_program(1);
270         }
271         ist = input_streams[input_files[file_idx]->ist_index + st->index];
272     } else {
273         /* find the first unused stream of corresponding type */
274         for (i = 0; i < nb_input_streams; i++) {
275             ist = input_streams[i];
276             if (ist->dec_ctx->codec_type == type && ist->discard)
277                 break;
278         }
279         if (i == nb_input_streams) {
280             av_log(NULL, AV_LOG_FATAL, "Cannot find a matching stream for "
281                    "unlabeled input pad %d on filter %s\n", in->pad_idx,
282                    in->filter_ctx->name);
283             exit_program(1);
284         }
285     }
286     av_assert0(ist);
287
288     ist->discard         = 0;
289     ist->decoding_needed |= DECODING_FOR_FILTER;
290     ist->st->discard = AVDISCARD_NONE;
291
292     GROW_ARRAY(fg->inputs, fg->nb_inputs);
293     if (!(fg->inputs[fg->nb_inputs - 1] = av_mallocz(sizeof(*fg->inputs[0]))))
294         exit_program(1);
295     fg->inputs[fg->nb_inputs - 1]->ist   = ist;
296     fg->inputs[fg->nb_inputs - 1]->graph = fg;
297     fg->inputs[fg->nb_inputs - 1]->format = -1;
298
299     GROW_ARRAY(ist->filters, ist->nb_filters);
300     ist->filters[ist->nb_filters - 1] = fg->inputs[fg->nb_inputs - 1];
301 }
302
303 int init_complex_filtergraph(FilterGraph *fg)
304 {
305     AVFilterInOut *inputs, *outputs, *cur;
306     AVFilterGraph *graph;
307     int ret = 0;
308
309     /* this graph is only used for determining the kinds of inputs
310      * and outputs we have, and is discarded on exit from this function */
311     graph = avfilter_graph_alloc();
312     if (!graph)
313         return AVERROR(ENOMEM);
314
315     ret = avfilter_graph_parse2(graph, fg->graph_desc, &inputs, &outputs);
316     if (ret < 0)
317         goto fail;
318
319     for (cur = inputs; cur; cur = cur->next)
320         init_input_filter(fg, cur);
321
322     for (cur = outputs; cur;) {
323         GROW_ARRAY(fg->outputs, fg->nb_outputs);
324         fg->outputs[fg->nb_outputs - 1] = av_mallocz(sizeof(*fg->outputs[0]));
325         if (!fg->outputs[fg->nb_outputs - 1])
326             exit_program(1);
327
328         fg->outputs[fg->nb_outputs - 1]->graph   = fg;
329         fg->outputs[fg->nb_outputs - 1]->out_tmp = cur;
330         fg->outputs[fg->nb_outputs - 1]->type    = avfilter_pad_get_type(cur->filter_ctx->output_pads,
331                                                                          cur->pad_idx);
332         cur = cur->next;
333         fg->outputs[fg->nb_outputs - 1]->out_tmp->next = NULL;
334     }
335
336 fail:
337     avfilter_inout_free(&inputs);
338     avfilter_graph_free(&graph);
339     return ret;
340 }
341
342 static int insert_trim(int64_t start_time, int64_t duration,
343                        AVFilterContext **last_filter, int *pad_idx,
344                        const char *filter_name)
345 {
346     AVFilterGraph *graph = (*last_filter)->graph;
347     AVFilterContext *ctx;
348     const AVFilter *trim;
349     enum AVMediaType type = avfilter_pad_get_type((*last_filter)->output_pads, *pad_idx);
350     const char *name = (type == AVMEDIA_TYPE_VIDEO) ? "trim" : "atrim";
351     int ret = 0;
352
353     if (duration == INT64_MAX && start_time == AV_NOPTS_VALUE)
354         return 0;
355
356     trim = avfilter_get_by_name(name);
357     if (!trim) {
358         av_log(NULL, AV_LOG_ERROR, "%s filter not present, cannot limit "
359                "recording time.\n", name);
360         return AVERROR_FILTER_NOT_FOUND;
361     }
362
363     ctx = avfilter_graph_alloc_filter(graph, trim, filter_name);
364     if (!ctx)
365         return AVERROR(ENOMEM);
366
367     if (duration != INT64_MAX) {
368         ret = av_opt_set_int(ctx, "durationi", duration,
369                                 AV_OPT_SEARCH_CHILDREN);
370     }
371     if (ret >= 0 && start_time != AV_NOPTS_VALUE) {
372         ret = av_opt_set_int(ctx, "starti", start_time,
373                                 AV_OPT_SEARCH_CHILDREN);
374     }
375     if (ret < 0) {
376         av_log(ctx, AV_LOG_ERROR, "Error configuring the %s filter", name);
377         return ret;
378     }
379
380     ret = avfilter_init_str(ctx, NULL);
381     if (ret < 0)
382         return ret;
383
384     ret = avfilter_link(*last_filter, *pad_idx, ctx, 0);
385     if (ret < 0)
386         return ret;
387
388     *last_filter = ctx;
389     *pad_idx     = 0;
390     return 0;
391 }
392
393 static int insert_filter(AVFilterContext **last_filter, int *pad_idx,
394                          const char *filter_name, const char *args)
395 {
396     AVFilterGraph *graph = (*last_filter)->graph;
397     AVFilterContext *ctx;
398     int ret;
399
400     ret = avfilter_graph_create_filter(&ctx,
401                                        avfilter_get_by_name(filter_name),
402                                        filter_name, args, NULL, graph);
403     if (ret < 0)
404         return ret;
405
406     ret = avfilter_link(*last_filter, *pad_idx, ctx, 0);
407     if (ret < 0)
408         return ret;
409
410     *last_filter = ctx;
411     *pad_idx     = 0;
412     return 0;
413 }
414
415 static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
416 {
417     char *pix_fmts;
418     OutputStream *ost = ofilter->ost;
419     OutputFile    *of = output_files[ost->file_index];
420     AVFilterContext *last_filter = out->filter_ctx;
421     int pad_idx = out->pad_idx;
422     int ret;
423     char name[255];
424
425     snprintf(name, sizeof(name), "out_%d_%d", ost->file_index, ost->index);
426     ret = avfilter_graph_create_filter(&ofilter->filter,
427                                        avfilter_get_by_name("buffersink"),
428                                        name, NULL, NULL, fg->graph);
429
430     if (ret < 0)
431         return ret;
432
433     if (!hw_device_ctx && (ofilter->width || ofilter->height)) {
434         char args[255];
435         AVFilterContext *filter;
436         AVDictionaryEntry *e = NULL;
437
438         snprintf(args, sizeof(args), "%d:%d",
439                  ofilter->width, ofilter->height);
440
441         while ((e = av_dict_get(ost->sws_dict, "", e,
442                                 AV_DICT_IGNORE_SUFFIX))) {
443             av_strlcatf(args, sizeof(args), ":%s=%s", e->key, e->value);
444         }
445
446         snprintf(name, sizeof(name), "scaler_out_%d_%d",
447                  ost->file_index, ost->index);
448         if ((ret = avfilter_graph_create_filter(&filter, avfilter_get_by_name("scale"),
449                                                 name, args, NULL, fg->graph)) < 0)
450             return ret;
451         if ((ret = avfilter_link(last_filter, pad_idx, filter, 0)) < 0)
452             return ret;
453
454         last_filter = filter;
455         pad_idx = 0;
456     }
457
458     if ((pix_fmts = choose_pix_fmts(ofilter))) {
459         AVFilterContext *filter;
460         snprintf(name, sizeof(name), "format_out_%d_%d",
461                  ost->file_index, ost->index);
462         ret = avfilter_graph_create_filter(&filter,
463                                            avfilter_get_by_name("format"),
464                                            "format", pix_fmts, NULL, fg->graph);
465         av_freep(&pix_fmts);
466         if (ret < 0)
467             return ret;
468         if ((ret = avfilter_link(last_filter, pad_idx, filter, 0)) < 0)
469             return ret;
470
471         last_filter = filter;
472         pad_idx     = 0;
473     }
474
475     if (ost->frame_rate.num && 0) {
476         AVFilterContext *fps;
477         char args[255];
478
479         snprintf(args, sizeof(args), "fps=%d/%d", ost->frame_rate.num,
480                  ost->frame_rate.den);
481         snprintf(name, sizeof(name), "fps_out_%d_%d",
482                  ost->file_index, ost->index);
483         ret = avfilter_graph_create_filter(&fps, avfilter_get_by_name("fps"),
484                                            name, args, NULL, fg->graph);
485         if (ret < 0)
486             return ret;
487
488         ret = avfilter_link(last_filter, pad_idx, fps, 0);
489         if (ret < 0)
490             return ret;
491         last_filter = fps;
492         pad_idx = 0;
493     }
494
495     snprintf(name, sizeof(name), "trim_out_%d_%d",
496              ost->file_index, ost->index);
497     ret = insert_trim(of->start_time, of->recording_time,
498                       &last_filter, &pad_idx, name);
499     if (ret < 0)
500         return ret;
501
502
503     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
504         return ret;
505
506     return 0;
507 }
508
509 static int configure_output_audio_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
510 {
511     OutputStream *ost = ofilter->ost;
512     OutputFile    *of = output_files[ost->file_index];
513     AVCodecContext *codec  = ost->enc_ctx;
514     AVFilterContext *last_filter = out->filter_ctx;
515     int pad_idx = out->pad_idx;
516     char *sample_fmts, *sample_rates, *channel_layouts;
517     char name[255];
518     int ret;
519
520     snprintf(name, sizeof(name), "out_%d_%d", ost->file_index, ost->index);
521     ret = avfilter_graph_create_filter(&ofilter->filter,
522                                        avfilter_get_by_name("abuffersink"),
523                                        name, NULL, NULL, fg->graph);
524     if (ret < 0)
525         return ret;
526     if ((ret = av_opt_set_int(ofilter->filter, "all_channel_counts", 1, AV_OPT_SEARCH_CHILDREN)) < 0)
527         return ret;
528
529 #define AUTO_INSERT_FILTER(opt_name, filter_name, arg) do {                 \
530     AVFilterContext *filt_ctx;                                              \
531                                                                             \
532     av_log(NULL, AV_LOG_INFO, opt_name " is forwarded to lavfi "            \
533            "similarly to -af " filter_name "=%s.\n", arg);                  \
534                                                                             \
535     ret = avfilter_graph_create_filter(&filt_ctx,                           \
536                                        avfilter_get_by_name(filter_name),   \
537                                        filter_name, arg, NULL, fg->graph);  \
538     if (ret < 0)                                                            \
539         return ret;                                                         \
540                                                                             \
541     ret = avfilter_link(last_filter, pad_idx, filt_ctx, 0);                 \
542     if (ret < 0)                                                            \
543         return ret;                                                         \
544                                                                             \
545     last_filter = filt_ctx;                                                 \
546     pad_idx = 0;                                                            \
547 } while (0)
548     if (ost->audio_channels_mapped) {
549         int i;
550         AVBPrint pan_buf;
551         av_bprint_init(&pan_buf, 256, 8192);
552         av_bprintf(&pan_buf, "0x%"PRIx64,
553                    av_get_default_channel_layout(ost->audio_channels_mapped));
554         for (i = 0; i < ost->audio_channels_mapped; i++)
555             if (ost->audio_channels_map[i] != -1)
556                 av_bprintf(&pan_buf, "|c%d=c%d", i, ost->audio_channels_map[i]);
557
558         AUTO_INSERT_FILTER("-map_channel", "pan", pan_buf.str);
559         av_bprint_finalize(&pan_buf, NULL);
560     }
561
562     if (codec->channels && !codec->channel_layout)
563         codec->channel_layout = av_get_default_channel_layout(codec->channels);
564
565     sample_fmts     = choose_sample_fmts(ofilter);
566     sample_rates    = choose_sample_rates(ofilter);
567     channel_layouts = choose_channel_layouts(ofilter);
568     if (sample_fmts || sample_rates || channel_layouts) {
569         AVFilterContext *format;
570         char args[256];
571         args[0] = 0;
572
573         if (sample_fmts)
574             av_strlcatf(args, sizeof(args), "sample_fmts=%s:",
575                             sample_fmts);
576         if (sample_rates)
577             av_strlcatf(args, sizeof(args), "sample_rates=%s:",
578                             sample_rates);
579         if (channel_layouts)
580             av_strlcatf(args, sizeof(args), "channel_layouts=%s:",
581                             channel_layouts);
582
583         av_freep(&sample_fmts);
584         av_freep(&sample_rates);
585         av_freep(&channel_layouts);
586
587         snprintf(name, sizeof(name), "format_out_%d_%d",
588                  ost->file_index, ost->index);
589         ret = avfilter_graph_create_filter(&format,
590                                            avfilter_get_by_name("aformat"),
591                                            name, args, NULL, fg->graph);
592         if (ret < 0)
593             return ret;
594
595         ret = avfilter_link(last_filter, pad_idx, format, 0);
596         if (ret < 0)
597             return ret;
598
599         last_filter = format;
600         pad_idx = 0;
601     }
602
603     if (audio_volume != 256 && 0) {
604         char args[256];
605
606         snprintf(args, sizeof(args), "%f", audio_volume / 256.);
607         AUTO_INSERT_FILTER("-vol", "volume", args);
608     }
609
610     if (ost->apad && of->shortest) {
611         char args[256];
612         int i;
613
614         for (i=0; i<of->ctx->nb_streams; i++)
615             if (of->ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
616                 break;
617
618         if (i<of->ctx->nb_streams) {
619             snprintf(args, sizeof(args), "%s", ost->apad);
620             AUTO_INSERT_FILTER("-apad", "apad", args);
621         }
622     }
623
624     snprintf(name, sizeof(name), "trim for output stream %d:%d",
625              ost->file_index, ost->index);
626     ret = insert_trim(of->start_time, of->recording_time,
627                       &last_filter, &pad_idx, name);
628     if (ret < 0)
629         return ret;
630
631     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
632         return ret;
633
634     return 0;
635 }
636
637 #define DESCRIBE_FILTER_LINK(f, inout, in)                         \
638 {                                                                  \
639     AVFilterContext *ctx = inout->filter_ctx;                      \
640     AVFilterPad *pads = in ? ctx->input_pads  : ctx->output_pads;  \
641     int       nb_pads = in ? ctx->nb_inputs   : ctx->nb_outputs;   \
642     AVIOContext *pb;                                               \
643                                                                    \
644     if (avio_open_dyn_buf(&pb) < 0)                                \
645         exit_program(1);                                           \
646                                                                    \
647     avio_printf(pb, "%s", ctx->filter->name);                      \
648     if (nb_pads > 1)                                               \
649         avio_printf(pb, ":%s", avfilter_pad_get_name(pads, inout->pad_idx));\
650     avio_w8(pb, 0);                                                \
651     avio_close_dyn_buf(pb, &f->name);                              \
652 }
653
654 int configure_output_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
655 {
656     av_freep(&ofilter->name);
657     DESCRIBE_FILTER_LINK(ofilter, out, 0);
658
659     if (!ofilter->ost) {
660         av_log(NULL, AV_LOG_FATAL, "Filter %s has an unconnected output\n", ofilter->name);
661         exit_program(1);
662     }
663
664     switch (avfilter_pad_get_type(out->filter_ctx->output_pads, out->pad_idx)) {
665     case AVMEDIA_TYPE_VIDEO: return configure_output_video_filter(fg, ofilter, out);
666     case AVMEDIA_TYPE_AUDIO: return configure_output_audio_filter(fg, ofilter, out);
667     default: av_assert0(0);
668     }
669 }
670
671 static int sub2video_prepare(InputStream *ist, InputFilter *ifilter)
672 {
673     AVFormatContext *avf = input_files[ist->file_index]->ctx;
674     int i, w, h;
675
676     /* Compute the size of the canvas for the subtitles stream.
677        If the subtitles codecpar has set a size, use it. Otherwise use the
678        maximum dimensions of the video streams in the same file. */
679     w = ifilter->width;
680     h = ifilter->height;
681     if (!(w && h)) {
682         for (i = 0; i < avf->nb_streams; i++) {
683             if (avf->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
684                 w = FFMAX(w, avf->streams[i]->codecpar->width);
685                 h = FFMAX(h, avf->streams[i]->codecpar->height);
686             }
687         }
688         if (!(w && h)) {
689             w = FFMAX(w, 720);
690             h = FFMAX(h, 576);
691         }
692         av_log(avf, AV_LOG_INFO, "sub2video: using %dx%d canvas\n", w, h);
693     }
694     ist->sub2video.w = ist->resample_width  = ifilter->width  = w;
695     ist->sub2video.h = ist->resample_height = ifilter->height = h;
696
697     /* rectangles are AV_PIX_FMT_PAL8, but we have no guarantee that the
698        palettes for all rectangles are identical or compatible */
699     ist->resample_pix_fmt = ifilter->format = AV_PIX_FMT_RGB32;
700
701     ist->sub2video.frame = av_frame_alloc();
702     if (!ist->sub2video.frame)
703         return AVERROR(ENOMEM);
704     ist->sub2video.last_pts = INT64_MIN;
705     return 0;
706 }
707
708 static int configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,
709                                         AVFilterInOut *in)
710 {
711     AVFilterContext *last_filter;
712     const AVFilter *buffer_filt = avfilter_get_by_name("buffer");
713     InputStream *ist = ifilter->ist;
714     InputFile     *f = input_files[ist->file_index];
715     AVRational tb = ist->framerate.num ? av_inv_q(ist->framerate) :
716                                          ist->st->time_base;
717     AVRational fr = ist->framerate;
718     AVRational sar;
719     AVBPrint args;
720     char name[255];
721     int ret, pad_idx = 0;
722     int64_t tsoffset = 0;
723     AVBufferSrcParameters *par = av_buffersrc_parameters_alloc();
724
725     if (!par)
726         return AVERROR(ENOMEM);
727     memset(par, 0, sizeof(*par));
728     par->format = AV_PIX_FMT_NONE;
729
730     if (ist->dec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) {
731         av_log(NULL, AV_LOG_ERROR, "Cannot connect video filter to audio input\n");
732         ret = AVERROR(EINVAL);
733         goto fail;
734     }
735
736     if (!fr.num)
737         fr = av_guess_frame_rate(input_files[ist->file_index]->ctx, ist->st, NULL);
738
739     if (ist->dec_ctx->codec_type == AVMEDIA_TYPE_SUBTITLE) {
740         ret = sub2video_prepare(ist, ifilter);
741         if (ret < 0)
742             goto fail;
743     }
744
745     sar = ifilter->sample_aspect_ratio;
746     if(!sar.den)
747         sar = (AVRational){0,1};
748     av_bprint_init(&args, 0, 1);
749     av_bprintf(&args,
750              "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:"
751              "pixel_aspect=%d/%d:sws_param=flags=%d",
752              ifilter->width, ifilter->height, ifilter->format,
753              tb.num, tb.den, sar.num, sar.den,
754              SWS_BILINEAR + ((ist->dec_ctx->flags&AV_CODEC_FLAG_BITEXACT) ? SWS_BITEXACT:0));
755     if (fr.num && fr.den)
756         av_bprintf(&args, ":frame_rate=%d/%d", fr.num, fr.den);
757     snprintf(name, sizeof(name), "graph %d input from stream %d:%d", fg->index,
758              ist->file_index, ist->st->index);
759
760
761     if ((ret = avfilter_graph_create_filter(&ifilter->filter, buffer_filt, name,
762                                             args.str, NULL, fg->graph)) < 0)
763         goto fail;
764     par->hw_frames_ctx = ifilter->hw_frames_ctx;
765     ret = av_buffersrc_parameters_set(ifilter->filter, par);
766     if (ret < 0)
767         goto fail;
768     av_freep(&par);
769     last_filter = ifilter->filter;
770
771     if (ist->autorotate) {
772         double theta = get_rotation(ist->st);
773
774         if (fabs(theta - 90) < 1.0) {
775             ret = insert_filter(&last_filter, &pad_idx, "transpose", "clock");
776         } else if (fabs(theta - 180) < 1.0) {
777             ret = insert_filter(&last_filter, &pad_idx, "hflip", NULL);
778             if (ret < 0)
779                 return ret;
780             ret = insert_filter(&last_filter, &pad_idx, "vflip", NULL);
781         } else if (fabs(theta - 270) < 1.0) {
782             ret = insert_filter(&last_filter, &pad_idx, "transpose", "cclock");
783         } else if (fabs(theta) > 1.0) {
784             char rotate_buf[64];
785             snprintf(rotate_buf, sizeof(rotate_buf), "%f*PI/180", theta);
786             ret = insert_filter(&last_filter, &pad_idx, "rotate", rotate_buf);
787         }
788         if (ret < 0)
789             return ret;
790     }
791
792     if (ist->framerate.num) {
793         AVFilterContext *setpts;
794
795         snprintf(name, sizeof(name), "forcecfr_in_%d_%d",
796                  ist->file_index, ist->st->index);
797         if ((ret = avfilter_graph_create_filter(&setpts,
798                                                 avfilter_get_by_name("setpts"),
799                                                 name, "N", NULL,
800                                                 fg->graph)) < 0)
801             return ret;
802
803         if ((ret = avfilter_link(last_filter, 0, setpts, 0)) < 0)
804             return ret;
805
806         last_filter = setpts;
807     }
808
809     if (do_deinterlace) {
810         AVFilterContext *yadif;
811
812         snprintf(name, sizeof(name), "deinterlace_in_%d_%d",
813                  ist->file_index, ist->st->index);
814         if ((ret = avfilter_graph_create_filter(&yadif,
815                                                 avfilter_get_by_name("yadif"),
816                                                 name, "", NULL,
817                                                 fg->graph)) < 0)
818             return ret;
819
820         if ((ret = avfilter_link(last_filter, 0, yadif, 0)) < 0)
821             return ret;
822
823         last_filter = yadif;
824     }
825
826     snprintf(name, sizeof(name), "trim_in_%d_%d",
827              ist->file_index, ist->st->index);
828     if (copy_ts) {
829         tsoffset = f->start_time == AV_NOPTS_VALUE ? 0 : f->start_time;
830         if (!start_at_zero && f->ctx->start_time != AV_NOPTS_VALUE)
831             tsoffset += f->ctx->start_time;
832     }
833     ret = insert_trim(((f->start_time == AV_NOPTS_VALUE) || !f->accurate_seek) ?
834                       AV_NOPTS_VALUE : tsoffset, f->recording_time,
835                       &last_filter, &pad_idx, name);
836     if (ret < 0)
837         return ret;
838
839     if ((ret = avfilter_link(last_filter, 0, in->filter_ctx, in->pad_idx)) < 0)
840         return ret;
841     return 0;
842 fail:
843     av_freep(&par);
844
845     return ret;
846 }
847
848 static int configure_input_audio_filter(FilterGraph *fg, InputFilter *ifilter,
849                                         AVFilterInOut *in)
850 {
851     AVFilterContext *last_filter;
852     const AVFilter *abuffer_filt = avfilter_get_by_name("abuffer");
853     InputStream *ist = ifilter->ist;
854     InputFile     *f = input_files[ist->file_index];
855     AVBPrint args;
856     char name[255];
857     int ret, pad_idx = 0;
858     int64_t tsoffset = 0;
859
860     if (ist->dec_ctx->codec_type != AVMEDIA_TYPE_AUDIO) {
861         av_log(NULL, AV_LOG_ERROR, "Cannot connect audio filter to non audio input\n");
862         return AVERROR(EINVAL);
863     }
864
865     av_bprint_init(&args, 0, AV_BPRINT_SIZE_AUTOMATIC);
866     av_bprintf(&args, "time_base=%d/%d:sample_rate=%d:sample_fmt=%s",
867              1, ifilter->sample_rate,
868              ifilter->sample_rate,
869              av_get_sample_fmt_name(ifilter->format));
870     if (ifilter->channel_layout)
871         av_bprintf(&args, ":channel_layout=0x%"PRIx64,
872                    ifilter->channel_layout);
873     else
874         av_bprintf(&args, ":channels=%d", ifilter->channels);
875     snprintf(name, sizeof(name), "graph_%d_in_%d_%d", fg->index,
876              ist->file_index, ist->st->index);
877
878     if ((ret = avfilter_graph_create_filter(&ifilter->filter, abuffer_filt,
879                                             name, args.str, NULL,
880                                             fg->graph)) < 0)
881         return ret;
882     last_filter = ifilter->filter;
883
884 #define AUTO_INSERT_FILTER_INPUT(opt_name, filter_name, arg) do {                 \
885     AVFilterContext *filt_ctx;                                              \
886                                                                             \
887     av_log(NULL, AV_LOG_INFO, opt_name " is forwarded to lavfi "            \
888            "similarly to -af " filter_name "=%s.\n", arg);                  \
889                                                                             \
890     snprintf(name, sizeof(name), "graph_%d_%s_in_%d_%d",      \
891                 fg->index, filter_name, ist->file_index, ist->st->index);   \
892     ret = avfilter_graph_create_filter(&filt_ctx,                           \
893                                        avfilter_get_by_name(filter_name),   \
894                                        name, arg, NULL, fg->graph);         \
895     if (ret < 0)                                                            \
896         return ret;                                                         \
897                                                                             \
898     ret = avfilter_link(last_filter, 0, filt_ctx, 0);                       \
899     if (ret < 0)                                                            \
900         return ret;                                                         \
901                                                                             \
902     last_filter = filt_ctx;                                                 \
903 } while (0)
904
905     if (audio_sync_method > 0) {
906         char args[256] = {0};
907
908         av_strlcatf(args, sizeof(args), "async=%d", audio_sync_method);
909         if (audio_drift_threshold != 0.1)
910             av_strlcatf(args, sizeof(args), ":min_hard_comp=%f", audio_drift_threshold);
911         if (!fg->reconfiguration)
912             av_strlcatf(args, sizeof(args), ":first_pts=0");
913         AUTO_INSERT_FILTER_INPUT("-async", "aresample", args);
914     }
915
916 //     if (ost->audio_channels_mapped) {
917 //         int i;
918 //         AVBPrint pan_buf;
919 //         av_bprint_init(&pan_buf, 256, 8192);
920 //         av_bprintf(&pan_buf, "0x%"PRIx64,
921 //                    av_get_default_channel_layout(ost->audio_channels_mapped));
922 //         for (i = 0; i < ost->audio_channels_mapped; i++)
923 //             if (ost->audio_channels_map[i] != -1)
924 //                 av_bprintf(&pan_buf, ":c%d=c%d", i, ost->audio_channels_map[i]);
925 //         AUTO_INSERT_FILTER_INPUT("-map_channel", "pan", pan_buf.str);
926 //         av_bprint_finalize(&pan_buf, NULL);
927 //     }
928
929     if (audio_volume != 256) {
930         char args[256];
931
932         av_log(NULL, AV_LOG_WARNING, "-vol has been deprecated. Use the volume "
933                "audio filter instead.\n");
934
935         snprintf(args, sizeof(args), "%f", audio_volume / 256.);
936         AUTO_INSERT_FILTER_INPUT("-vol", "volume", args);
937     }
938
939     snprintf(name, sizeof(name), "trim for input stream %d:%d",
940              ist->file_index, ist->st->index);
941     if (copy_ts) {
942         tsoffset = f->start_time == AV_NOPTS_VALUE ? 0 : f->start_time;
943         if (!start_at_zero && f->ctx->start_time != AV_NOPTS_VALUE)
944             tsoffset += f->ctx->start_time;
945     }
946     ret = insert_trim(((f->start_time == AV_NOPTS_VALUE) || !f->accurate_seek) ?
947                       AV_NOPTS_VALUE : tsoffset, f->recording_time,
948                       &last_filter, &pad_idx, name);
949     if (ret < 0)
950         return ret;
951
952     if ((ret = avfilter_link(last_filter, 0, in->filter_ctx, in->pad_idx)) < 0)
953         return ret;
954
955     return 0;
956 }
957
958 static int configure_input_filter(FilterGraph *fg, InputFilter *ifilter,
959                                   AVFilterInOut *in)
960 {
961     av_freep(&ifilter->name);
962     DESCRIBE_FILTER_LINK(ifilter, in, 1);
963
964     if (!ifilter->ist->dec) {
965         av_log(NULL, AV_LOG_ERROR,
966                "No decoder for stream #%d:%d, filtering impossible\n",
967                ifilter->ist->file_index, ifilter->ist->st->index);
968         return AVERROR_DECODER_NOT_FOUND;
969     }
970     switch (avfilter_pad_get_type(in->filter_ctx->input_pads, in->pad_idx)) {
971     case AVMEDIA_TYPE_VIDEO: return configure_input_video_filter(fg, ifilter, in);
972     case AVMEDIA_TYPE_AUDIO: return configure_input_audio_filter(fg, ifilter, in);
973     default: av_assert0(0);
974     }
975 }
976
977 int configure_filtergraph(FilterGraph *fg)
978 {
979     AVFilterInOut *inputs, *outputs, *cur;
980     int ret, i, simple = filtergraph_is_simple(fg);
981     const char *graph_desc = simple ? fg->outputs[0]->ost->avfilter :
982                                       fg->graph_desc;
983
984     avfilter_graph_free(&fg->graph);
985     if (!(fg->graph = avfilter_graph_alloc()))
986         return AVERROR(ENOMEM);
987
988     if (simple) {
989         OutputStream *ost = fg->outputs[0]->ost;
990         char args[512];
991         AVDictionaryEntry *e = NULL;
992
993         fg->graph->nb_threads = filter_nbthreads;
994
995         args[0] = 0;
996         while ((e = av_dict_get(ost->sws_dict, "", e,
997                                 AV_DICT_IGNORE_SUFFIX))) {
998             av_strlcatf(args, sizeof(args), "%s=%s:", e->key, e->value);
999         }
1000         if (strlen(args))
1001             args[strlen(args)-1] = 0;
1002         fg->graph->scale_sws_opts = av_strdup(args);
1003
1004         args[0] = 0;
1005         while ((e = av_dict_get(ost->swr_opts, "", e,
1006                                 AV_DICT_IGNORE_SUFFIX))) {
1007             av_strlcatf(args, sizeof(args), "%s=%s:", e->key, e->value);
1008         }
1009         if (strlen(args))
1010             args[strlen(args)-1] = 0;
1011         av_opt_set(fg->graph, "aresample_swr_opts", args, 0);
1012
1013         args[0] = '\0';
1014         while ((e = av_dict_get(fg->outputs[0]->ost->resample_opts, "", e,
1015                                 AV_DICT_IGNORE_SUFFIX))) {
1016             av_strlcatf(args, sizeof(args), "%s=%s:", e->key, e->value);
1017         }
1018         if (strlen(args))
1019             args[strlen(args) - 1] = '\0';
1020         fg->graph->resample_lavr_opts = av_strdup(args);
1021
1022         e = av_dict_get(ost->encoder_opts, "threads", NULL, 0);
1023         if (e)
1024             av_opt_set(fg->graph, "threads", e->value, 0);
1025     } else {
1026         fg->graph->nb_threads = filter_complex_nbthreads;
1027     }
1028
1029     if ((ret = avfilter_graph_parse2(fg->graph, graph_desc, &inputs, &outputs)) < 0)
1030         return ret;
1031
1032     if (hw_device_ctx) {
1033         for (i = 0; i < fg->graph->nb_filters; i++) {
1034             fg->graph->filters[i]->hw_device_ctx = av_buffer_ref(hw_device_ctx);
1035         }
1036     }
1037
1038     if (simple && (!inputs || inputs->next || !outputs || outputs->next)) {
1039         const char *num_inputs;
1040         const char *num_outputs;
1041         if (!outputs) {
1042             num_outputs = "0";
1043         } else if (outputs->next) {
1044             num_outputs = ">1";
1045         } else {
1046             num_outputs = "1";
1047         }
1048         if (!inputs) {
1049             num_inputs = "0";
1050         } else if (inputs->next) {
1051             num_inputs = ">1";
1052         } else {
1053             num_inputs = "1";
1054         }
1055         av_log(NULL, AV_LOG_ERROR, "Simple filtergraph '%s' was expected "
1056                "to have exactly 1 input and 1 output."
1057                " However, it had %s input(s) and %s output(s)."
1058                " Please adjust, or use a complex filtergraph (-filter_complex) instead.\n",
1059                graph_desc, num_inputs, num_outputs);
1060         return AVERROR(EINVAL);
1061     }
1062
1063     for (cur = inputs, i = 0; cur; cur = cur->next, i++)
1064         if ((ret = configure_input_filter(fg, fg->inputs[i], cur)) < 0) {
1065             avfilter_inout_free(&inputs);
1066             avfilter_inout_free(&outputs);
1067             return ret;
1068         }
1069     avfilter_inout_free(&inputs);
1070
1071     for (cur = outputs, i = 0; cur; cur = cur->next, i++)
1072         configure_output_filter(fg, fg->outputs[i], cur);
1073     avfilter_inout_free(&outputs);
1074
1075     if ((ret = avfilter_graph_config(fg->graph, NULL)) < 0)
1076         return ret;
1077
1078     /* limit the lists of allowed formats to the ones selected, to
1079      * make sure they stay the same if the filtergraph is reconfigured later */
1080     for (i = 0; i < fg->nb_outputs; i++) {
1081         OutputFilter *ofilter = fg->outputs[i];
1082         AVFilterContext *sink = ofilter->filter;
1083
1084         ofilter->format = av_buffersink_get_format(sink);
1085
1086         ofilter->width  = av_buffersink_get_w(sink);
1087         ofilter->height = av_buffersink_get_h(sink);
1088
1089         ofilter->sample_rate    = av_buffersink_get_sample_rate(sink);
1090         ofilter->channel_layout = av_buffersink_get_channel_layout(sink);
1091     }
1092
1093     fg->reconfiguration = 1;
1094
1095     for (i = 0; i < fg->nb_outputs; i++) {
1096         OutputStream *ost = fg->outputs[i]->ost;
1097         if (!ost->enc) {
1098             /* identical to the same check in ffmpeg.c, needed because
1099                complex filter graphs are initialized earlier */
1100             av_log(NULL, AV_LOG_ERROR, "Encoder (codec %s) not found for output stream #%d:%d\n",
1101                      avcodec_get_name(ost->st->codecpar->codec_id), ost->file_index, ost->index);
1102             return AVERROR(EINVAL);
1103         }
1104         if (ost->enc->type == AVMEDIA_TYPE_AUDIO &&
1105             !(ost->enc->capabilities & AV_CODEC_CAP_VARIABLE_FRAME_SIZE))
1106             av_buffersink_set_frame_size(ost->filter->filter,
1107                                          ost->enc_ctx->frame_size);
1108     }
1109
1110     return 0;
1111 }
1112
1113 int ifilter_parameters_from_frame(InputFilter *ifilter, const AVFrame *frame)
1114 {
1115     av_buffer_unref(&ifilter->hw_frames_ctx);
1116
1117     ifilter->format = frame->format;
1118
1119     ifilter->width               = frame->width;
1120     ifilter->height              = frame->height;
1121     ifilter->sample_aspect_ratio = frame->sample_aspect_ratio;
1122
1123     ifilter->sample_rate         = frame->sample_rate;
1124     ifilter->channels            = av_frame_get_channels(frame);
1125     ifilter->channel_layout      = frame->channel_layout;
1126
1127     if (frame->hw_frames_ctx) {
1128         ifilter->hw_frames_ctx = av_buffer_ref(frame->hw_frames_ctx);
1129         if (!ifilter->hw_frames_ctx)
1130             return AVERROR(ENOMEM);
1131     }
1132
1133     return 0;
1134 }
1135
1136 int ifilter_parameters_from_decoder(InputFilter *ifilter, const AVCodecContext *avctx)
1137 {
1138     av_buffer_unref(&ifilter->hw_frames_ctx);
1139
1140     if (avctx->codec_type == AVMEDIA_TYPE_VIDEO)
1141         ifilter->format = avctx->pix_fmt;
1142     else
1143         ifilter->format = avctx->sample_fmt;
1144
1145     ifilter->width               = avctx->width;
1146     ifilter->height              = avctx->height;
1147     if (ifilter->ist && ifilter->ist->st && ifilter->ist->st->sample_aspect_ratio.num)
1148         ifilter->sample_aspect_ratio = ifilter->ist->st->sample_aspect_ratio;
1149     else
1150         ifilter->sample_aspect_ratio = avctx->sample_aspect_ratio;
1151
1152     ifilter->sample_rate         = avctx->sample_rate;
1153     ifilter->channels            = avctx->channels;
1154     ifilter->channel_layout      = avctx->channel_layout;
1155
1156     if (ifilter->ist && ifilter->ist->hw_frames_ctx) {
1157         ifilter->format = ifilter->ist->resample_pix_fmt;
1158         ifilter->hw_frames_ctx = av_buffer_ref(ifilter->ist->hw_frames_ctx);
1159         if (!ifilter->hw_frames_ctx)
1160             return AVERROR(ENOMEM);
1161     }
1162
1163     return 0;
1164 }
1165
1166 int ist_in_filtergraph(FilterGraph *fg, InputStream *ist)
1167 {
1168     int i;
1169     for (i = 0; i < fg->nb_inputs; i++)
1170         if (fg->inputs[i]->ist == ist)
1171             return 1;
1172     return 0;
1173 }
1174
1175 int filtergraph_is_simple(FilterGraph *fg)
1176 {
1177     return !fg->graph_desc;
1178 }