git.sesse.net Git - ffmpeg/blob - avconv_filter.c

   1 /*
   2  * avconv filter configuration
   3  *
   4  * This file is part of Libav.
   5  *
   6  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include "avconv.h"
  22
  23 #include "libavfilter/avfilter.h"
  24
  25 #include "libavresample/avresample.h"
  26
  27 #include "libavutil/avassert.h"
  28 #include "libavutil/avstring.h"
  29 #include "libavutil/channel_layout.h"
  30 #include "libavutil/opt.h"
  31 #include "libavutil/pixdesc.h"
  32 #include "libavutil/pixfmt.h"
  33 #include "libavutil/samplefmt.h"
  34
  35 /* Define a function for building a string containing a list of
  36  * allowed formats. */
  37 #define DEF_CHOOSE_FORMAT(type, var, supported_list, none, get_name)           \
  38 static char *choose_ ## var ## s(OutputStream *ost)                            \
  39 {                                                                              \
  40     if (ost->st->codec->var != none) {                                         \
  41         get_name(ost->st->codec->var);                                         \
  42         return av_strdup(name);                                                \
  43     } else if (ost->enc && ost->enc->supported_list) {                         \
  44         const type *p;                                                         \
  45         AVIOContext *s = NULL;                                                 \
  46         uint8_t *ret;                                                          \
  47         int len;                                                               \
  48                                                                                \
  49         if (avio_open_dyn_buf(&s) < 0)                                         \
  50             exit(1);                                                           \
  51                                                                                \
  52         for (p = ost->enc->supported_list; *p != none; p++) {                  \
  53             get_name(*p);                                                      \
  54             avio_printf(s, "%s|", name);                                       \
  55         }                                                                      \
  56         len = avio_close_dyn_buf(s, &ret);                                     \
  57         ret[len - 1] = 0;                                                      \
  58         return ret;                                                            \
  59     } else                                                                     \
  60         return NULL;                                                           \
  61 }
  62
  63 DEF_CHOOSE_FORMAT(enum AVPixelFormat, pix_fmt, pix_fmts, AV_PIX_FMT_NONE,
  64                   GET_PIX_FMT_NAME)
  65
  66 DEF_CHOOSE_FORMAT(enum AVSampleFormat, sample_fmt, sample_fmts,
  67                   AV_SAMPLE_FMT_NONE, GET_SAMPLE_FMT_NAME)
  68
  69 DEF_CHOOSE_FORMAT(int, sample_rate, supported_samplerates, 0,
  70                   GET_SAMPLE_RATE_NAME)
  71
  72 DEF_CHOOSE_FORMAT(uint64_t, channel_layout, channel_layouts, 0,
  73                   GET_CH_LAYOUT_NAME)
  74
  75 FilterGraph *init_simple_filtergraph(InputStream *ist, OutputStream *ost)
  76 {
  77     FilterGraph *fg = av_mallocz(sizeof(*fg));
  78
  79     if (!fg)
  80         exit(1);
  81     fg->index = nb_filtergraphs;
  82
  83     GROW_ARRAY(fg->outputs, fg->nb_outputs);
  84     if (!(fg->outputs[0] = av_mallocz(sizeof(*fg->outputs[0]))))
  85         exit(1);
  86     fg->outputs[0]->ost   = ost;
  87     fg->outputs[0]->graph = fg;
  88
  89     ost->filter = fg->outputs[0];
  90
  91     GROW_ARRAY(fg->inputs, fg->nb_inputs);
  92     if (!(fg->inputs[0] = av_mallocz(sizeof(*fg->inputs[0]))))
  93         exit(1);
  94     fg->inputs[0]->ist   = ist;
  95     fg->inputs[0]->graph = fg;
  96
  97     GROW_ARRAY(ist->filters, ist->nb_filters);
  98     ist->filters[ist->nb_filters - 1] = fg->inputs[0];
  99
 100     GROW_ARRAY(filtergraphs, nb_filtergraphs);
 101     filtergraphs[nb_filtergraphs - 1] = fg;
 102
 103     return fg;
 104 }
 105
 106 static void init_input_filter(FilterGraph *fg, AVFilterInOut *in)
 107 {
 108     InputStream *ist = NULL;
 109     enum AVMediaType type = avfilter_pad_get_type(in->filter_ctx->input_pads, in->pad_idx);
 110     int i;
 111
 112     // TODO: support other filter types
 113     if (type != AVMEDIA_TYPE_VIDEO && type != AVMEDIA_TYPE_AUDIO) {
 114         av_log(NULL, AV_LOG_FATAL, "Only video and audio filters supported "
 115                "currently.\n");
 116         exit(1);
 117     }
 118
 119     if (in->name) {
 120         AVFormatContext *s;
 121         AVStream       *st = NULL;
 122         char *p;
 123         int file_idx = strtol(in->name, &p, 0);
 124
 125         if (file_idx < 0 || file_idx >= nb_input_files) {
 126             av_log(NULL, AV_LOG_FATAL, "Invalid file index %d in filtegraph description %s.\n",
 127                    file_idx, fg->graph_desc);
 128             exit(1);
 129         }
 130         s = input_files[file_idx]->ctx;
 131
 132         for (i = 0; i < s->nb_streams; i++) {
 133             if (s->streams[i]->codec->codec_type != type)
 134                 continue;
 135             if (check_stream_specifier(s, s->streams[i], *p == ':' ? p + 1 : p) == 1) {
 136                 st = s->streams[i];
 137                 break;
 138             }
 139         }
 140         if (!st) {
 141             av_log(NULL, AV_LOG_FATAL, "Stream specifier '%s' in filtergraph description %s "
 142                    "matches no streams.\n", p, fg->graph_desc);
 143             exit(1);
 144         }
 145         ist = input_streams[input_files[file_idx]->ist_index + st->index];
 146     } else {
 147         /* find the first unused stream of corresponding type */
 148         for (i = 0; i < nb_input_streams; i++) {
 149             ist = input_streams[i];
 150             if (ist->st->codec->codec_type == type && ist->discard)
 151                 break;
 152         }
 153         if (i == nb_input_streams) {
 154             av_log(NULL, AV_LOG_FATAL, "Cannot find a matching stream for "
 155                    "unlabeled input pad %d on filter %s", in->pad_idx,
 156                    in->filter_ctx->name);
 157             exit(1);
 158         }
 159     }
 160     av_assert0(ist);
 161
 162     ist->discard         = 0;
 163     ist->decoding_needed = 1;
 164     ist->st->discard = AVDISCARD_NONE;
 165
 166     GROW_ARRAY(fg->inputs, fg->nb_inputs);
 167     if (!(fg->inputs[fg->nb_inputs - 1] = av_mallocz(sizeof(*fg->inputs[0]))))
 168         exit(1);
 169     fg->inputs[fg->nb_inputs - 1]->ist   = ist;
 170     fg->inputs[fg->nb_inputs - 1]->graph = fg;
 171
 172     GROW_ARRAY(ist->filters, ist->nb_filters);
 173     ist->filters[ist->nb_filters - 1] = fg->inputs[fg->nb_inputs - 1];
 174 }
 175
 176 static int insert_trim(int64_t start_time, int64_t duration,
 177                        AVFilterContext **last_filter, int *pad_idx,
 178                        const char *filter_name)
 179 {
 180     AVFilterGraph *graph = (*last_filter)->graph;
 181     AVFilterContext *ctx;
 182     const AVFilter *trim;
 183     enum AVMediaType type = avfilter_pad_get_type((*last_filter)->output_pads, *pad_idx);
 184     const char *name = (type == AVMEDIA_TYPE_VIDEO) ? "trim" : "atrim";
 185     int ret = 0;
 186
 187     if (duration == INT64_MAX && start_time == AV_NOPTS_VALUE)
 188         return 0;
 189
 190     trim = avfilter_get_by_name(name);
 191     if (!trim) {
 192         av_log(NULL, AV_LOG_ERROR, "%s filter not present, cannot limit "
 193                "recording time.\n", name);
 194         return AVERROR_FILTER_NOT_FOUND;
 195     }
 196
 197     ctx = avfilter_graph_alloc_filter(graph, trim, filter_name);
 198     if (!ctx)
 199         return AVERROR(ENOMEM);
 200
 201     if (duration != INT64_MAX) {
 202         ret = av_opt_set_double(ctx, "duration", (double)duration / 1e6,
 203                                 AV_OPT_SEARCH_CHILDREN);
 204     }
 205     if (ret >= 0 && start_time != AV_NOPTS_VALUE) {
 206         ret = av_opt_set_double(ctx, "start", (double)start_time / 1e6,
 207                                 AV_OPT_SEARCH_CHILDREN);
 208     }
 209     if (ret < 0) {
 210         av_log(ctx, AV_LOG_ERROR, "Error configuring the %s filter", name);
 211         return ret;
 212     }
 213
 214     ret = avfilter_init_str(ctx, NULL);
 215     if (ret < 0)
 216         return ret;
 217
 218     ret = avfilter_link(*last_filter, *pad_idx, ctx, 0);
 219     if (ret < 0)
 220         return ret;
 221
 222     *last_filter = ctx;
 223     *pad_idx     = 0;
 224     return 0;
 225 }
 226
 227 static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 228 {
 229     char *pix_fmts;
 230     OutputStream *ost = ofilter->ost;
 231     OutputFile    *of = output_files[ost->file_index];
 232     AVCodecContext *codec = ost->st->codec;
 233     AVFilterContext *last_filter = out->filter_ctx;
 234     int pad_idx = out->pad_idx;
 235     int ret;
 236     char name[255];
 237
 238     snprintf(name, sizeof(name), "output stream %d:%d", ost->file_index, ost->index);
 239     ret = avfilter_graph_create_filter(&ofilter->filter,
 240                                        avfilter_get_by_name("buffersink"),
 241                                        name, NULL, NULL, fg->graph);
 242     if (ret < 0)
 243         return ret;
 244
 245     if (codec->width || codec->height) {
 246         char args[255];
 247         AVFilterContext *filter;
 248
 249         snprintf(args, sizeof(args), "%d:%d:0x%X",
 250                  codec->width,
 251                  codec->height,
 252                  (unsigned)ost->sws_flags);
 253         snprintf(name, sizeof(name), "scaler for output stream %d:%d",
 254                  ost->file_index, ost->index);
 255         if ((ret = avfilter_graph_create_filter(&filter, avfilter_get_by_name("scale"),
 256                                                 name, args, NULL, fg->graph)) < 0)
 257             return ret;
 258         if ((ret = avfilter_link(last_filter, pad_idx, filter, 0)) < 0)
 259             return ret;
 260
 261         last_filter = filter;
 262         pad_idx = 0;
 263     }
 264
 265     if ((pix_fmts = choose_pix_fmts(ost))) {
 266         AVFilterContext *filter;
 267         snprintf(name, sizeof(name), "pixel format for output stream %d:%d",
 268                  ost->file_index, ost->index);
 269         if ((ret = avfilter_graph_create_filter(&filter,
 270                                                 avfilter_get_by_name("format"),
 271                                                 "format", pix_fmts, NULL,
 272                                                 fg->graph)) < 0)
 273             return ret;
 274         if ((ret = avfilter_link(last_filter, pad_idx, filter, 0)) < 0)
 275             return ret;
 276
 277         last_filter = filter;
 278         pad_idx     = 0;
 279         av_freep(&pix_fmts);
 280     }
 281
 282     if (ost->frame_rate.num) {
 283         AVFilterContext *fps;
 284         char args[255];
 285
 286         snprintf(args, sizeof(args), "fps=%d/%d", ost->frame_rate.num,
 287                  ost->frame_rate.den);
 288         snprintf(name, sizeof(name), "fps for output stream %d:%d",
 289                  ost->file_index, ost->index);
 290         ret = avfilter_graph_create_filter(&fps, avfilter_get_by_name("fps"),
 291                                            name, args, NULL, fg->graph);
 292         if (ret < 0)
 293             return ret;
 294
 295         ret = avfilter_link(last_filter, pad_idx, fps, 0);
 296         if (ret < 0)
 297             return ret;
 298         last_filter = fps;
 299         pad_idx = 0;
 300     }
 301
 302     snprintf(name, sizeof(name), "trim for output stream %d:%d",
 303              ost->file_index, ost->index);
 304     ret = insert_trim(of->start_time, of->recording_time,
 305                       &last_filter, &pad_idx, name);
 306     if (ret < 0)
 307         return ret;
 308
 309
 310     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
 311         return ret;
 312
 313     return 0;
 314 }
 315
 316 static int configure_output_audio_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 317 {
 318     OutputStream *ost = ofilter->ost;
 319     OutputFile    *of = output_files[ost->file_index];
 320     AVCodecContext *codec  = ost->st->codec;
 321     AVFilterContext *last_filter = out->filter_ctx;
 322     int pad_idx = out->pad_idx;
 323     char *sample_fmts, *sample_rates, *channel_layouts;
 324     char name[255];
 325     int ret;
 326
 327
 328     snprintf(name, sizeof(name), "output stream %d:%d", ost->file_index, ost->index);
 329     ret = avfilter_graph_create_filter(&ofilter->filter,
 330                                        avfilter_get_by_name("abuffersink"),
 331                                        name, NULL, NULL, fg->graph);
 332     if (ret < 0)
 333         return ret;
 334
 335     if (codec->channels && !codec->channel_layout)
 336         codec->channel_layout = av_get_default_channel_layout(codec->channels);
 337
 338     sample_fmts     = choose_sample_fmts(ost);
 339     sample_rates    = choose_sample_rates(ost);
 340     channel_layouts = choose_channel_layouts(ost);
 341     if (sample_fmts || sample_rates || channel_layouts) {
 342         AVFilterContext *format;
 343         char args[256];
 344         int len = 0;
 345
 346         if (sample_fmts)
 347             len += snprintf(args + len, sizeof(args) - len, "sample_fmts=%s:",
 348                             sample_fmts);
 349         if (sample_rates)
 350             len += snprintf(args + len, sizeof(args) - len, "sample_rates=%s:",
 351                             sample_rates);
 352         if (channel_layouts)
 353             len += snprintf(args + len, sizeof(args) - len, "channel_layouts=%s:",
 354                             channel_layouts);
 355         args[len - 1] = 0;
 356
 357         av_freep(&sample_fmts);
 358         av_freep(&sample_rates);
 359         av_freep(&channel_layouts);
 360
 361         snprintf(name, sizeof(name), "audio format for output stream %d:%d",
 362                  ost->file_index, ost->index);
 363         ret = avfilter_graph_create_filter(&format,
 364                                            avfilter_get_by_name("aformat"),
 365                                            name, args, NULL, fg->graph);
 366         if (ret < 0)
 367             return ret;
 368
 369         ret = avfilter_link(last_filter, pad_idx, format, 0);
 370         if (ret < 0)
 371             return ret;
 372
 373         last_filter = format;
 374         pad_idx = 0;
 375     }
 376
 377     snprintf(name, sizeof(name), "trim for output stream %d:%d",
 378              ost->file_index, ost->index);
 379     ret = insert_trim(of->start_time, of->recording_time,
 380                       &last_filter, &pad_idx, name);
 381     if (ret < 0)
 382         return ret;
 383
 384     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
 385         return ret;
 386
 387     return 0;
 388 }
 389
 390 #define DESCRIBE_FILTER_LINK(f, inout, in)                         \
 391 {                                                                  \
 392     AVFilterContext *ctx = inout->filter_ctx;                      \
 393     AVFilterPad *pads = in ? ctx->input_pads  : ctx->output_pads;  \
 394     int       nb_pads = in ? ctx->nb_inputs   : ctx->nb_outputs;   \
 395     AVIOContext *pb;                                               \
 396                                                                    \
 397     if (avio_open_dyn_buf(&pb) < 0)                                \
 398         exit(1);                                                   \
 399                                                                    \
 400     avio_printf(pb, "%s", ctx->filter->name);                      \
 401     if (nb_pads > 1)                                               \
 402         avio_printf(pb, ":%s", avfilter_pad_get_name(pads, inout->pad_idx));\
 403     avio_w8(pb, 0);                                                \
 404     avio_close_dyn_buf(pb, &f->name);                              \
 405 }
 406
 407 int configure_output_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 408 {
 409     av_freep(&ofilter->name);
 410     DESCRIBE_FILTER_LINK(ofilter, out, 0);
 411
 412     switch (avfilter_pad_get_type(out->filter_ctx->output_pads, out->pad_idx)) {
 413     case AVMEDIA_TYPE_VIDEO: return configure_output_video_filter(fg, ofilter, out);
 414     case AVMEDIA_TYPE_AUDIO: return configure_output_audio_filter(fg, ofilter, out);
 415     default: av_assert0(0);
 416     }
 417 }
 418
 419 static int configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,
 420                                         AVFilterInOut *in)
 421 {
 422     AVFilterContext *last_filter;
 423     const AVFilter *buffer_filt = avfilter_get_by_name("buffer");
 424     InputStream *ist = ifilter->ist;
 425     InputFile     *f = input_files[ist->file_index];
 426     AVRational tb = ist->framerate.num ? av_inv_q(ist->framerate) :
 427                                          ist->st->time_base;
 428     AVRational sar;
 429     char args[255], name[255];
 430     int ret, pad_idx = 0;
 431
 432     sar = ist->st->sample_aspect_ratio.num ?
 433           ist->st->sample_aspect_ratio :
 434           ist->st->codec->sample_aspect_ratio;
 435     snprintf(args, sizeof(args), "%d:%d:%d:%d:%d:%d:%d", ist->st->codec->width,
 436              ist->st->codec->height, ist->st->codec->pix_fmt,
 437              tb.num, tb.den, sar.num, sar.den);
 438     snprintf(name, sizeof(name), "graph %d input from stream %d:%d", fg->index,
 439              ist->file_index, ist->st->index);
 440
 441     if ((ret = avfilter_graph_create_filter(&ifilter->filter, buffer_filt, name,
 442                                             args, NULL, fg->graph)) < 0)
 443         return ret;
 444     last_filter = ifilter->filter;
 445
 446     if (ist->framerate.num) {
 447         AVFilterContext *setpts;
 448
 449         snprintf(name, sizeof(name), "force CFR for input from stream %d:%d",
 450                  ist->file_index, ist->st->index);
 451         if ((ret = avfilter_graph_create_filter(&setpts,
 452                                                 avfilter_get_by_name("setpts"),
 453                                                 name, "N", NULL,
 454                                                 fg->graph)) < 0)
 455             return ret;
 456
 457         if ((ret = avfilter_link(last_filter, 0, setpts, 0)) < 0)
 458             return ret;
 459
 460         last_filter = setpts;
 461     }
 462
 463     snprintf(name, sizeof(name), "trim for input stream %d:%d",
 464              ist->file_index, ist->st->index);
 465     ret = insert_trim(((f->start_time == AV_NOPTS_VALUE) || !f->accurate_seek) ?
 466                       AV_NOPTS_VALUE : 0, f->recording_time, &last_filter, &pad_idx, name);
 467     if (ret < 0)
 468         return ret;
 469
 470     if ((ret = avfilter_link(last_filter, 0, in->filter_ctx, in->pad_idx)) < 0)
 471         return ret;
 472     return 0;
 473 }
 474
 475 static int configure_input_audio_filter(FilterGraph *fg, InputFilter *ifilter,
 476                                         AVFilterInOut *in)
 477 {
 478     AVFilterContext *last_filter;
 479     const AVFilter *abuffer_filt = avfilter_get_by_name("abuffer");
 480     InputStream *ist = ifilter->ist;
 481     InputFile     *f = input_files[ist->file_index];
 482     char args[255], name[255];
 483     int ret, pad_idx = 0;
 484
 485     snprintf(args, sizeof(args), "time_base=%d/%d:sample_rate=%d:sample_fmt=%s"
 486              ":channel_layout=0x%"PRIx64,
 487              1, ist->st->codec->sample_rate,
 488              ist->st->codec->sample_rate,
 489              av_get_sample_fmt_name(ist->st->codec->sample_fmt),
 490              ist->st->codec->channel_layout);
 491     snprintf(name, sizeof(name), "graph %d input from stream %d:%d", fg->index,
 492              ist->file_index, ist->st->index);
 493
 494     if ((ret = avfilter_graph_create_filter(&ifilter->filter, abuffer_filt,
 495                                             name, args, NULL,
 496                                             fg->graph)) < 0)
 497         return ret;
 498     last_filter = ifilter->filter;
 499
 500     if (audio_sync_method > 0) {
 501         AVFilterContext *async;
 502         int  len = 0;
 503
 504         av_log(NULL, AV_LOG_WARNING, "-async has been deprecated. Used the "
 505                "asyncts audio filter instead.\n");
 506
 507         if (audio_sync_method > 1)
 508             len += snprintf(args + len, sizeof(args) - len, "compensate=1:"
 509                             "max_comp=%d:", audio_sync_method);
 510         snprintf(args + len, sizeof(args) - len, "min_delta=%f",
 511                  audio_drift_threshold);
 512
 513         snprintf(name, sizeof(name), "graph %d audio sync for input stream %d:%d",
 514                  fg->index, ist->file_index, ist->st->index);
 515         ret = avfilter_graph_create_filter(&async,
 516                                            avfilter_get_by_name("asyncts"),
 517                                            name, args, NULL, fg->graph);
 518         if (ret < 0)
 519             return ret;
 520
 521         ret = avfilter_link(last_filter, 0, async, 0);
 522         if (ret < 0)
 523             return ret;
 524
 525         last_filter = async;
 526     }
 527     if (audio_volume != 256) {
 528         AVFilterContext *volume;
 529
 530         av_log(NULL, AV_LOG_WARNING, "-vol has been deprecated. Use the volume "
 531                "audio filter instead.\n");
 532
 533         snprintf(args, sizeof(args), "volume=%f", audio_volume / 256.0);
 534
 535         snprintf(name, sizeof(name), "graph %d volume for input stream %d:%d",
 536                  fg->index, ist->file_index, ist->st->index);
 537         ret = avfilter_graph_create_filter(&volume,
 538                                            avfilter_get_by_name("volume"),
 539                                            name, args, NULL, fg->graph);
 540         if (ret < 0)
 541             return ret;
 542
 543         ret = avfilter_link(last_filter, 0, volume, 0);
 544         if (ret < 0)
 545             return ret;
 546
 547         last_filter = volume;
 548     }
 549
 550     snprintf(name, sizeof(name), "trim for input stream %d:%d",
 551              ist->file_index, ist->st->index);
 552     ret = insert_trim(((f->start_time == AV_NOPTS_VALUE) || !f->accurate_seek) ?
 553                       AV_NOPTS_VALUE : 0, f->recording_time, &last_filter, &pad_idx, name);
 554     if (ret < 0)
 555         return ret;
 556
 557     if ((ret = avfilter_link(last_filter, 0, in->filter_ctx, in->pad_idx)) < 0)
 558         return ret;
 559
 560     return 0;
 561 }
 562
 563 static int configure_input_filter(FilterGraph *fg, InputFilter *ifilter,
 564                                   AVFilterInOut *in)
 565 {
 566     av_freep(&ifilter->name);
 567     DESCRIBE_FILTER_LINK(ifilter, in, 1);
 568
 569     switch (avfilter_pad_get_type(in->filter_ctx->input_pads, in->pad_idx)) {
 570     case AVMEDIA_TYPE_VIDEO: return configure_input_video_filter(fg, ifilter, in);
 571     case AVMEDIA_TYPE_AUDIO: return configure_input_audio_filter(fg, ifilter, in);
 572     default: av_assert0(0);
 573     }
 574 }
 575
 576 int configure_filtergraph(FilterGraph *fg)
 577 {
 578     AVFilterInOut *inputs, *outputs, *cur;
 579     int ret, i, init = !fg->graph, simple = !fg->graph_desc;
 580     const char *graph_desc = simple ? fg->outputs[0]->ost->avfilter :
 581                                       fg->graph_desc;
 582
 583     avfilter_graph_free(&fg->graph);
 584     if (!(fg->graph = avfilter_graph_alloc()))
 585         return AVERROR(ENOMEM);
 586
 587     if (simple) {
 588         OutputStream *ost = fg->outputs[0]->ost;
 589         char args[512];
 590         AVDictionaryEntry *e = NULL;
 591
 592         snprintf(args, sizeof(args), "flags=0x%X", (unsigned)ost->sws_flags);
 593         fg->graph->scale_sws_opts = av_strdup(args);
 594
 595         args[0] = '\0';
 596         while ((e = av_dict_get(fg->outputs[0]->ost->resample_opts, "", e,
 597                                 AV_DICT_IGNORE_SUFFIX))) {
 598             av_strlcatf(args, sizeof(args), "%s=%s:", e->key, e->value);
 599         }
 600         if (strlen(args))
 601             args[strlen(args) - 1] = '\0';
 602         fg->graph->resample_lavr_opts = av_strdup(args);
 603     }
 604
 605     if ((ret = avfilter_graph_parse2(fg->graph, graph_desc, &inputs, &outputs)) < 0)
 606         return ret;
 607
 608     if (simple && (!inputs || inputs->next || !outputs || outputs->next)) {
 609         av_log(NULL, AV_LOG_ERROR, "Simple filtergraph '%s' does not have "
 610                "exactly one input and output.\n", graph_desc);
 611         return AVERROR(EINVAL);
 612     }
 613
 614     for (cur = inputs; !simple && init && cur; cur = cur->next)
 615         init_input_filter(fg, cur);
 616
 617     for (cur = inputs, i = 0; cur; cur = cur->next, i++)
 618         if ((ret = configure_input_filter(fg, fg->inputs[i], cur)) < 0)
 619             return ret;
 620     avfilter_inout_free(&inputs);
 621
 622     if (!init || simple) {
 623         /* we already know the mappings between lavfi outputs and output streams,
 624          * so we can finish the setup */
 625         for (cur = outputs, i = 0; cur; cur = cur->next, i++)
 626             configure_output_filter(fg, fg->outputs[i], cur);
 627         avfilter_inout_free(&outputs);
 628
 629         if ((ret = avfilter_graph_config(fg->graph, NULL)) < 0)
 630             return ret;
 631     } else {
 632         /* wait until output mappings are processed */
 633         for (cur = outputs; cur;) {
 634             GROW_ARRAY(fg->outputs, fg->nb_outputs);
 635             if (!(fg->outputs[fg->nb_outputs - 1] = av_mallocz(sizeof(*fg->outputs[0]))))
 636                 exit(1);
 637             fg->outputs[fg->nb_outputs - 1]->graph   = fg;
 638             fg->outputs[fg->nb_outputs - 1]->out_tmp = cur;
 639             cur = cur->next;
 640             fg->outputs[fg->nb_outputs - 1]->out_tmp->next = NULL;
 641         }
 642     }
 643
 644     return 0;
 645 }
 646
 647 int ist_in_filtergraph(FilterGraph *fg, InputStream *ist)
 648 {
 649     int i;
 650     for (i = 0; i < fg->nb_inputs; i++)
 651         if (fg->inputs[i]->ist == ist)
 652             return 1;
 653     return 0;
 654 }
 655