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 <stdint.h>
  22
  23 #include "avconv.h"
  24
  25 #include "libavfilter/avfilter.h"
  26
  27 #include "libavresample/avresample.h"
  28
  29 #include "libavutil/avassert.h"
  30 #include "libavutil/avstring.h"
  31 #include "libavutil/channel_layout.h"
  32 #include "libavutil/display.h"
  33 #include "libavutil/opt.h"
  34 #include "libavutil/pixdesc.h"
  35 #include "libavutil/pixfmt.h"
  36 #include "libavutil/samplefmt.h"
  37
  38 /* Define a function for building a string containing a list of
  39  * allowed formats. */
  40 #define DEF_CHOOSE_FORMAT(type, var, supported_list, none, get_name)           \
  41 static char *choose_ ## var ## s(OutputStream *ost)                            \
  42 {                                                                              \
  43     if (ost->enc_ctx->var != none) {                                           \
  44         get_name(ost->enc_ctx->var);                                           \
  45         return av_strdup(name);                                                \
  46     } else if (ost->enc && ost->enc->supported_list) {                         \
  47         const type *p;                                                         \
  48         AVIOContext *s = NULL;                                                 \
  49         uint8_t *ret;                                                          \
  50         int len;                                                               \
  51                                                                                \
  52         if (avio_open_dyn_buf(&s) < 0)                                         \
  53             exit(1);                                                           \
  54                                                                                \
  55         for (p = ost->enc->supported_list; *p != none; p++) {                  \
  56             get_name(*p);                                                      \
  57             avio_printf(s, "%s|", name);                                       \
  58         }                                                                      \
  59         len = avio_close_dyn_buf(s, &ret);                                     \
  60         ret[len - 1] = 0;                                                      \
  61         return ret;                                                            \
  62     } else                                                                     \
  63         return NULL;                                                           \
  64 }
  65
  66 DEF_CHOOSE_FORMAT(enum AVPixelFormat, pix_fmt, pix_fmts, AV_PIX_FMT_NONE,
  67                   GET_PIX_FMT_NAME)
  68
  69 DEF_CHOOSE_FORMAT(enum AVSampleFormat, sample_fmt, sample_fmts,
  70                   AV_SAMPLE_FMT_NONE, GET_SAMPLE_FMT_NAME)
  71
  72 DEF_CHOOSE_FORMAT(int, sample_rate, supported_samplerates, 0,
  73                   GET_SAMPLE_RATE_NAME)
  74
  75 DEF_CHOOSE_FORMAT(uint64_t, channel_layout, channel_layouts, 0,
  76                   GET_CH_LAYOUT_NAME)
  77
  78 FilterGraph *init_simple_filtergraph(InputStream *ist, OutputStream *ost)
  79 {
  80     FilterGraph *fg = av_mallocz(sizeof(*fg));
  81
  82     if (!fg)
  83         exit(1);
  84     fg->index = nb_filtergraphs;
  85
  86     GROW_ARRAY(fg->outputs, fg->nb_outputs);
  87     if (!(fg->outputs[0] = av_mallocz(sizeof(*fg->outputs[0]))))
  88         exit(1);
  89     fg->outputs[0]->ost   = ost;
  90     fg->outputs[0]->graph = fg;
  91
  92     ost->filter = fg->outputs[0];
  93
  94     GROW_ARRAY(fg->inputs, fg->nb_inputs);
  95     if (!(fg->inputs[0] = av_mallocz(sizeof(*fg->inputs[0]))))
  96         exit(1);
  97     fg->inputs[0]->ist   = ist;
  98     fg->inputs[0]->graph = fg;
  99
 100     GROW_ARRAY(ist->filters, ist->nb_filters);
 101     ist->filters[ist->nb_filters - 1] = fg->inputs[0];
 102
 103     GROW_ARRAY(filtergraphs, nb_filtergraphs);
 104     filtergraphs[nb_filtergraphs - 1] = fg;
 105
 106     return fg;
 107 }
 108
 109 static void init_input_filter(FilterGraph *fg, AVFilterInOut *in)
 110 {
 111     InputStream *ist = NULL;
 112     enum AVMediaType type = avfilter_pad_get_type(in->filter_ctx->input_pads, in->pad_idx);
 113     int i;
 114
 115     // TODO: support other filter types
 116     if (type != AVMEDIA_TYPE_VIDEO && type != AVMEDIA_TYPE_AUDIO) {
 117         av_log(NULL, AV_LOG_FATAL, "Only video and audio filters supported "
 118                "currently.\n");
 119         exit(1);
 120     }
 121
 122     if (in->name) {
 123         AVFormatContext *s;
 124         AVStream       *st = NULL;
 125         char *p;
 126         int file_idx = strtol(in->name, &p, 0);
 127
 128         if (file_idx < 0 || file_idx >= nb_input_files) {
 129             av_log(NULL, AV_LOG_FATAL, "Invalid file index %d in filtegraph description %s.\n",
 130                    file_idx, fg->graph_desc);
 131             exit(1);
 132         }
 133         s = input_files[file_idx]->ctx;
 134
 135         for (i = 0; i < s->nb_streams; i++) {
 136             if (s->streams[i]->codec->codec_type != type)
 137                 continue;
 138             if (check_stream_specifier(s, s->streams[i], *p == ':' ? p + 1 : p) == 1) {
 139                 st = s->streams[i];
 140                 break;
 141             }
 142         }
 143         if (!st) {
 144             av_log(NULL, AV_LOG_FATAL, "Stream specifier '%s' in filtergraph description %s "
 145                    "matches no streams.\n", p, fg->graph_desc);
 146             exit(1);
 147         }
 148         ist = input_streams[input_files[file_idx]->ist_index + st->index];
 149     } else {
 150         /* find the first unused stream of corresponding type */
 151         for (i = 0; i < nb_input_streams; i++) {
 152             ist = input_streams[i];
 153             if (ist->dec_ctx->codec_type == type && ist->discard)
 154                 break;
 155         }
 156         if (i == nb_input_streams) {
 157             av_log(NULL, AV_LOG_FATAL, "Cannot find a matching stream for "
 158                    "unlabeled input pad %d on filter %s\n", in->pad_idx,
 159                    in->filter_ctx->name);
 160             exit(1);
 161         }
 162     }
 163     av_assert0(ist);
 164
 165     ist->discard         = 0;
 166     ist->decoding_needed = 1;
 167     ist->st->discard = AVDISCARD_NONE;
 168
 169     GROW_ARRAY(fg->inputs, fg->nb_inputs);
 170     if (!(fg->inputs[fg->nb_inputs - 1] = av_mallocz(sizeof(*fg->inputs[0]))))
 171         exit(1);
 172     fg->inputs[fg->nb_inputs - 1]->ist   = ist;
 173     fg->inputs[fg->nb_inputs - 1]->graph = fg;
 174
 175     GROW_ARRAY(ist->filters, ist->nb_filters);
 176     ist->filters[ist->nb_filters - 1] = fg->inputs[fg->nb_inputs - 1];
 177 }
 178
 179 static int insert_trim(int64_t start_time, int64_t duration,
 180                        AVFilterContext **last_filter, int *pad_idx,
 181                        const char *filter_name)
 182 {
 183     AVFilterGraph *graph = (*last_filter)->graph;
 184     AVFilterContext *ctx;
 185     const AVFilter *trim;
 186     enum AVMediaType type = avfilter_pad_get_type((*last_filter)->output_pads, *pad_idx);
 187     const char *name = (type == AVMEDIA_TYPE_VIDEO) ? "trim" : "atrim";
 188     int ret = 0;
 189
 190     if (duration == INT64_MAX && start_time == AV_NOPTS_VALUE)
 191         return 0;
 192
 193     trim = avfilter_get_by_name(name);
 194     if (!trim) {
 195         av_log(NULL, AV_LOG_ERROR, "%s filter not present, cannot limit "
 196                "recording time.\n", name);
 197         return AVERROR_FILTER_NOT_FOUND;
 198     }
 199
 200     ctx = avfilter_graph_alloc_filter(graph, trim, filter_name);
 201     if (!ctx)
 202         return AVERROR(ENOMEM);
 203
 204     if (duration != INT64_MAX) {
 205         ret = av_opt_set_double(ctx, "duration", (double)duration / 1e6,
 206                                 AV_OPT_SEARCH_CHILDREN);
 207     }
 208     if (ret >= 0 && start_time != AV_NOPTS_VALUE) {
 209         ret = av_opt_set_double(ctx, "start", (double)start_time / 1e6,
 210                                 AV_OPT_SEARCH_CHILDREN);
 211     }
 212     if (ret < 0) {
 213         av_log(ctx, AV_LOG_ERROR, "Error configuring the %s filter", name);
 214         return ret;
 215     }
 216
 217     ret = avfilter_init_str(ctx, NULL);
 218     if (ret < 0)
 219         return ret;
 220
 221     ret = avfilter_link(*last_filter, *pad_idx, ctx, 0);
 222     if (ret < 0)
 223         return ret;
 224
 225     *last_filter = ctx;
 226     *pad_idx     = 0;
 227     return 0;
 228 }
 229
 230 static int insert_filter(AVFilterContext **last_filter, int *pad_idx,
 231                          const char *filter_name, const char *args)
 232 {
 233     AVFilterGraph *graph = (*last_filter)->graph;
 234     AVFilterContext *ctx;
 235     int ret;
 236
 237     ret = avfilter_graph_create_filter(&ctx,
 238                                        avfilter_get_by_name(filter_name),
 239                                        filter_name, args, NULL, graph);
 240     if (ret < 0)
 241         return ret;
 242
 243     ret = avfilter_link(*last_filter, *pad_idx, ctx, 0);
 244     if (ret < 0)
 245         return ret;
 246
 247     *last_filter = ctx;
 248     *pad_idx     = 0;
 249     return 0;
 250 }
 251
 252 static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 253 {
 254     char *pix_fmts;
 255     OutputStream *ost = ofilter->ost;
 256     OutputFile    *of = output_files[ost->file_index];
 257     AVCodecContext *codec = ost->enc_ctx;
 258     AVFilterContext *last_filter = out->filter_ctx;
 259     int pad_idx = out->pad_idx;
 260     int ret;
 261     char name[255];
 262
 263     snprintf(name, sizeof(name), "output stream %d:%d", ost->file_index, ost->index);
 264     ret = avfilter_graph_create_filter(&ofilter->filter,
 265                                        avfilter_get_by_name("buffersink"),
 266                                        name, NULL, NULL, fg->graph);
 267     if (ret < 0)
 268         return ret;
 269
 270     if (codec->width || codec->height) {
 271         char args[255];
 272         AVFilterContext *filter;
 273
 274         snprintf(args, sizeof(args), "%d:%d:0x%X",
 275                  codec->width,
 276                  codec->height,
 277                  (unsigned)ost->sws_flags);
 278         snprintf(name, sizeof(name), "scaler for output stream %d:%d",
 279                  ost->file_index, ost->index);
 280         if ((ret = avfilter_graph_create_filter(&filter, avfilter_get_by_name("scale"),
 281                                                 name, args, NULL, fg->graph)) < 0)
 282             return ret;
 283         if ((ret = avfilter_link(last_filter, pad_idx, filter, 0)) < 0)
 284             return ret;
 285
 286         last_filter = filter;
 287         pad_idx = 0;
 288     }
 289
 290     if ((pix_fmts = choose_pix_fmts(ost))) {
 291         AVFilterContext *filter;
 292         snprintf(name, sizeof(name), "pixel format for output stream %d:%d",
 293                  ost->file_index, ost->index);
 294         ret = avfilter_graph_create_filter(&filter,
 295                                            avfilter_get_by_name("format"),
 296                                            "format", pix_fmts, NULL, fg->graph);
 297         av_freep(&pix_fmts);
 298         if (ret < 0)
 299             return ret;
 300         if ((ret = avfilter_link(last_filter, pad_idx, filter, 0)) < 0)
 301             return ret;
 302
 303         last_filter = filter;
 304         pad_idx     = 0;
 305     }
 306
 307     if (ost->frame_rate.num) {
 308         AVFilterContext *fps;
 309         char args[255];
 310
 311         snprintf(args, sizeof(args), "fps=%d/%d", ost->frame_rate.num,
 312                  ost->frame_rate.den);
 313         snprintf(name, sizeof(name), "fps for output stream %d:%d",
 314                  ost->file_index, ost->index);
 315         ret = avfilter_graph_create_filter(&fps, avfilter_get_by_name("fps"),
 316                                            name, args, NULL, fg->graph);
 317         if (ret < 0)
 318             return ret;
 319
 320         ret = avfilter_link(last_filter, pad_idx, fps, 0);
 321         if (ret < 0)
 322             return ret;
 323         last_filter = fps;
 324         pad_idx = 0;
 325     }
 326
 327     snprintf(name, sizeof(name), "trim for output stream %d:%d",
 328              ost->file_index, ost->index);
 329     ret = insert_trim(of->start_time, of->recording_time,
 330                       &last_filter, &pad_idx, name);
 331     if (ret < 0)
 332         return ret;
 333
 334
 335     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
 336         return ret;
 337
 338     return 0;
 339 }
 340
 341 static int configure_output_audio_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 342 {
 343     OutputStream *ost = ofilter->ost;
 344     OutputFile    *of = output_files[ost->file_index];
 345     AVCodecContext *codec  = ost->enc_ctx;
 346     AVFilterContext *last_filter = out->filter_ctx;
 347     int pad_idx = out->pad_idx;
 348     char *sample_fmts, *sample_rates, *channel_layouts;
 349     char name[255];
 350     int ret;
 351
 352
 353     snprintf(name, sizeof(name), "output stream %d:%d", ost->file_index, ost->index);
 354     ret = avfilter_graph_create_filter(&ofilter->filter,
 355                                        avfilter_get_by_name("abuffersink"),
 356                                        name, NULL, NULL, fg->graph);
 357     if (ret < 0)
 358         return ret;
 359
 360     if (codec->channels && !codec->channel_layout)
 361         codec->channel_layout = av_get_default_channel_layout(codec->channels);
 362
 363     sample_fmts     = choose_sample_fmts(ost);
 364     sample_rates    = choose_sample_rates(ost);
 365     channel_layouts = choose_channel_layouts(ost);
 366     if (sample_fmts || sample_rates || channel_layouts) {
 367         AVFilterContext *format;
 368         char args[256];
 369         int len = 0;
 370
 371         if (sample_fmts)
 372             len += snprintf(args + len, sizeof(args) - len, "sample_fmts=%s:",
 373                             sample_fmts);
 374         if (sample_rates)
 375             len += snprintf(args + len, sizeof(args) - len, "sample_rates=%s:",
 376                             sample_rates);
 377         if (channel_layouts)
 378             len += snprintf(args + len, sizeof(args) - len, "channel_layouts=%s:",
 379                             channel_layouts);
 380         args[len - 1] = 0;
 381
 382         av_freep(&sample_fmts);
 383         av_freep(&sample_rates);
 384         av_freep(&channel_layouts);
 385
 386         snprintf(name, sizeof(name), "audio format for output stream %d:%d",
 387                  ost->file_index, ost->index);
 388         ret = avfilter_graph_create_filter(&format,
 389                                            avfilter_get_by_name("aformat"),
 390                                            name, args, NULL, fg->graph);
 391         if (ret < 0)
 392             return ret;
 393
 394         ret = avfilter_link(last_filter, pad_idx, format, 0);
 395         if (ret < 0)
 396             return ret;
 397
 398         last_filter = format;
 399         pad_idx = 0;
 400     }
 401
 402     snprintf(name, sizeof(name), "trim for output stream %d:%d",
 403              ost->file_index, ost->index);
 404     ret = insert_trim(of->start_time, of->recording_time,
 405                       &last_filter, &pad_idx, name);
 406     if (ret < 0)
 407         return ret;
 408
 409     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
 410         return ret;
 411
 412     return 0;
 413 }
 414
 415 #define DESCRIBE_FILTER_LINK(f, inout, in)                         \
 416 {                                                                  \
 417     AVFilterContext *ctx = inout->filter_ctx;                      \
 418     AVFilterPad *pads = in ? ctx->input_pads  : ctx->output_pads;  \
 419     int       nb_pads = in ? ctx->nb_inputs   : ctx->nb_outputs;   \
 420     AVIOContext *pb;                                               \
 421                                                                    \
 422     if (avio_open_dyn_buf(&pb) < 0)                                \
 423         exit(1);                                                   \
 424                                                                    \
 425     avio_printf(pb, "%s", ctx->filter->name);                      \
 426     if (nb_pads > 1)                                               \
 427         avio_printf(pb, ":%s", avfilter_pad_get_name(pads, inout->pad_idx));\
 428     avio_w8(pb, 0);                                                \
 429     avio_close_dyn_buf(pb, &f->name);                              \
 430 }
 431
 432 int configure_output_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 433 {
 434     av_freep(&ofilter->name);
 435     DESCRIBE_FILTER_LINK(ofilter, out, 0);
 436
 437     switch (avfilter_pad_get_type(out->filter_ctx->output_pads, out->pad_idx)) {
 438     case AVMEDIA_TYPE_VIDEO: return configure_output_video_filter(fg, ofilter, out);
 439     case AVMEDIA_TYPE_AUDIO: return configure_output_audio_filter(fg, ofilter, out);
 440     default: av_assert0(0);
 441     }
 442 }
 443
 444 static int configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,
 445                                         AVFilterInOut *in)
 446 {
 447     AVFilterContext *last_filter;
 448     const AVFilter *buffer_filt = avfilter_get_by_name("buffer");
 449     InputStream *ist = ifilter->ist;
 450     InputFile     *f = input_files[ist->file_index];
 451     AVRational tb = ist->framerate.num ? av_inv_q(ist->framerate) :
 452                                          ist->st->time_base;
 453     AVRational sar;
 454     char args[255], name[255];
 455     int ret, pad_idx = 0;
 456
 457     sar = ist->st->sample_aspect_ratio.num ?
 458           ist->st->sample_aspect_ratio :
 459           ist->dec_ctx->sample_aspect_ratio;
 460     snprintf(args, sizeof(args), "%d:%d:%d:%d:%d:%d:%d", ist->dec_ctx->width,
 461              ist->dec_ctx->height,
 462              ist->hwaccel_retrieve_data ? ist->hwaccel_retrieved_pix_fmt : ist->dec_ctx->pix_fmt,
 463              tb.num, tb.den, sar.num, sar.den);
 464     snprintf(name, sizeof(name), "graph %d input from stream %d:%d", fg->index,
 465              ist->file_index, ist->st->index);
 466
 467     if ((ret = avfilter_graph_create_filter(&ifilter->filter, buffer_filt, name,
 468                                             args, NULL, fg->graph)) < 0)
 469         return ret;
 470     last_filter = ifilter->filter;
 471
 472     if (ist->autorotate) {
 473         uint8_t* displaymatrix = av_stream_get_side_data(ist->st,
 474                                                          AV_PKT_DATA_DISPLAYMATRIX, NULL);
 475         if (displaymatrix) {
 476             double rot = av_display_rotation_get((int32_t*) displaymatrix);
 477             if (rot < -135 || rot > 135) {
 478                 ret = insert_filter(&last_filter, &pad_idx, "vflip", NULL);
 479                 if (ret < 0)
 480                     return ret;
 481                 ret = insert_filter(&last_filter, &pad_idx, "hflip", NULL);
 482             } else if (rot < -45) {
 483                 ret = insert_filter(&last_filter, &pad_idx, "transpose", "dir=clock");
 484             } else if (rot > 45) {
 485                 ret = insert_filter(&last_filter, &pad_idx, "transpose", "dir=cclock");
 486             }
 487             if (ret < 0)
 488                 return ret;
 489         }
 490     }
 491
 492     if (ist->framerate.num) {
 493         AVFilterContext *setpts;
 494
 495         snprintf(name, sizeof(name), "force CFR for input from stream %d:%d",
 496                  ist->file_index, ist->st->index);
 497         if ((ret = avfilter_graph_create_filter(&setpts,
 498                                                 avfilter_get_by_name("setpts"),
 499                                                 name, "N", NULL,
 500                                                 fg->graph)) < 0)
 501             return ret;
 502
 503         if ((ret = avfilter_link(last_filter, 0, setpts, 0)) < 0)
 504             return ret;
 505
 506         last_filter = setpts;
 507     }
 508
 509     snprintf(name, sizeof(name), "trim for input stream %d:%d",
 510              ist->file_index, ist->st->index);
 511     ret = insert_trim(((f->start_time == AV_NOPTS_VALUE) || !f->accurate_seek) ?
 512                       AV_NOPTS_VALUE : 0, f->recording_time, &last_filter, &pad_idx, name);
 513     if (ret < 0)
 514         return ret;
 515
 516     if ((ret = avfilter_link(last_filter, 0, in->filter_ctx, in->pad_idx)) < 0)
 517         return ret;
 518     return 0;
 519 }
 520
 521 static int configure_input_audio_filter(FilterGraph *fg, InputFilter *ifilter,
 522                                         AVFilterInOut *in)
 523 {
 524     AVFilterContext *last_filter;
 525     const AVFilter *abuffer_filt = avfilter_get_by_name("abuffer");
 526     InputStream *ist = ifilter->ist;
 527     InputFile     *f = input_files[ist->file_index];
 528     char args[255], name[255];
 529     int ret, pad_idx = 0;
 530
 531     snprintf(args, sizeof(args), "time_base=%d/%d:sample_rate=%d:sample_fmt=%s"
 532              ":channel_layout=0x%"PRIx64,
 533              1, ist->dec_ctx->sample_rate,
 534              ist->dec_ctx->sample_rate,
 535              av_get_sample_fmt_name(ist->dec_ctx->sample_fmt),
 536              ist->dec_ctx->channel_layout);
 537     snprintf(name, sizeof(name), "graph %d input from stream %d:%d", fg->index,
 538              ist->file_index, ist->st->index);
 539
 540     if ((ret = avfilter_graph_create_filter(&ifilter->filter, abuffer_filt,
 541                                             name, args, NULL,
 542                                             fg->graph)) < 0)
 543         return ret;
 544     last_filter = ifilter->filter;
 545
 546     if (audio_sync_method > 0) {
 547         AVFilterContext *async;
 548         int  len = 0;
 549
 550         av_log(NULL, AV_LOG_WARNING, "-async has been deprecated. Used the "
 551                "asyncts audio filter instead.\n");
 552
 553         if (audio_sync_method > 1)
 554             len += snprintf(args + len, sizeof(args) - len, "compensate=1:"
 555                             "max_comp=%d:", audio_sync_method);
 556         snprintf(args + len, sizeof(args) - len, "min_delta=%f",
 557                  audio_drift_threshold);
 558
 559         snprintf(name, sizeof(name), "graph %d audio sync for input stream %d:%d",
 560                  fg->index, ist->file_index, ist->st->index);
 561         ret = avfilter_graph_create_filter(&async,
 562                                            avfilter_get_by_name("asyncts"),
 563                                            name, args, NULL, fg->graph);
 564         if (ret < 0)
 565             return ret;
 566
 567         ret = avfilter_link(last_filter, 0, async, 0);
 568         if (ret < 0)
 569             return ret;
 570
 571         last_filter = async;
 572     }
 573     if (audio_volume != 256) {
 574         AVFilterContext *volume;
 575
 576         av_log(NULL, AV_LOG_WARNING, "-vol has been deprecated. Use the volume "
 577                "audio filter instead.\n");
 578
 579         snprintf(args, sizeof(args), "volume=%f", audio_volume / 256.0);
 580
 581         snprintf(name, sizeof(name), "graph %d volume for input stream %d:%d",
 582                  fg->index, ist->file_index, ist->st->index);
 583         ret = avfilter_graph_create_filter(&volume,
 584                                            avfilter_get_by_name("volume"),
 585                                            name, args, NULL, fg->graph);
 586         if (ret < 0)
 587             return ret;
 588
 589         ret = avfilter_link(last_filter, 0, volume, 0);
 590         if (ret < 0)
 591             return ret;
 592
 593         last_filter = volume;
 594     }
 595
 596     snprintf(name, sizeof(name), "trim for input stream %d:%d",
 597              ist->file_index, ist->st->index);
 598     ret = insert_trim(((f->start_time == AV_NOPTS_VALUE) || !f->accurate_seek) ?
 599                       AV_NOPTS_VALUE : 0, f->recording_time, &last_filter, &pad_idx, name);
 600     if (ret < 0)
 601         return ret;
 602
 603     if ((ret = avfilter_link(last_filter, 0, in->filter_ctx, in->pad_idx)) < 0)
 604         return ret;
 605
 606     return 0;
 607 }
 608
 609 static int configure_input_filter(FilterGraph *fg, InputFilter *ifilter,
 610                                   AVFilterInOut *in)
 611 {
 612     av_freep(&ifilter->name);
 613     DESCRIBE_FILTER_LINK(ifilter, in, 1);
 614
 615     switch (avfilter_pad_get_type(in->filter_ctx->input_pads, in->pad_idx)) {
 616     case AVMEDIA_TYPE_VIDEO: return configure_input_video_filter(fg, ifilter, in);
 617     case AVMEDIA_TYPE_AUDIO: return configure_input_audio_filter(fg, ifilter, in);
 618     default: av_assert0(0);
 619     }
 620 }
 621
 622 int configure_filtergraph(FilterGraph *fg)
 623 {
 624     AVFilterInOut *inputs, *outputs, *cur;
 625     int ret, i, init = !fg->graph, simple = !fg->graph_desc;
 626     const char *graph_desc = simple ? fg->outputs[0]->ost->avfilter :
 627                                       fg->graph_desc;
 628
 629     avfilter_graph_free(&fg->graph);
 630     if (!(fg->graph = avfilter_graph_alloc()))
 631         return AVERROR(ENOMEM);
 632
 633     if (simple) {
 634         OutputStream *ost = fg->outputs[0]->ost;
 635         char args[512];
 636         AVDictionaryEntry *e = NULL;
 637
 638         snprintf(args, sizeof(args), "flags=0x%X", (unsigned)ost->sws_flags);
 639         fg->graph->scale_sws_opts = av_strdup(args);
 640
 641         args[0] = '\0';
 642         while ((e = av_dict_get(fg->outputs[0]->ost->resample_opts, "", e,
 643                                 AV_DICT_IGNORE_SUFFIX))) {
 644             av_strlcatf(args, sizeof(args), "%s=%s:", e->key, e->value);
 645         }
 646         if (strlen(args))
 647             args[strlen(args) - 1] = '\0';
 648         fg->graph->resample_lavr_opts = av_strdup(args);
 649     }
 650
 651     if ((ret = avfilter_graph_parse2(fg->graph, graph_desc, &inputs, &outputs)) < 0)
 652         return ret;
 653
 654     if (simple && (!inputs || inputs->next || !outputs || outputs->next)) {
 655         av_log(NULL, AV_LOG_ERROR, "Simple filtergraph '%s' does not have "
 656                "exactly one input and output.\n", graph_desc);
 657         return AVERROR(EINVAL);
 658     }
 659
 660     for (cur = inputs; !simple && init && cur; cur = cur->next)
 661         init_input_filter(fg, cur);
 662
 663     for (cur = inputs, i = 0; cur; cur = cur->next, i++)
 664         if ((ret = configure_input_filter(fg, fg->inputs[i], cur)) < 0)
 665             return ret;
 666     avfilter_inout_free(&inputs);
 667
 668     if (!init || simple) {
 669         /* we already know the mappings between lavfi outputs and output streams,
 670          * so we can finish the setup */
 671         for (cur = outputs, i = 0; cur; cur = cur->next, i++)
 672             configure_output_filter(fg, fg->outputs[i], cur);
 673         avfilter_inout_free(&outputs);
 674
 675         if ((ret = avfilter_graph_config(fg->graph, NULL)) < 0)
 676             return ret;
 677     } else {
 678         /* wait until output mappings are processed */
 679         for (cur = outputs; cur;) {
 680             GROW_ARRAY(fg->outputs, fg->nb_outputs);
 681             if (!(fg->outputs[fg->nb_outputs - 1] = av_mallocz(sizeof(*fg->outputs[0]))))
 682                 exit(1);
 683             fg->outputs[fg->nb_outputs - 1]->graph   = fg;
 684             fg->outputs[fg->nb_outputs - 1]->out_tmp = cur;
 685             cur = cur->next;
 686             fg->outputs[fg->nb_outputs - 1]->out_tmp->next = NULL;
 687         }
 688     }
 689
 690     return 0;
 691 }
 692
 693 int ist_in_filtergraph(FilterGraph *fg, InputStream *ist)
 694 {
 695     int i;
 696     for (i = 0; i < fg->nb_inputs; i++)
 697         if (fg->inputs[i]->ist == ist)
 698             return 1;
 699     return 0;
 700 }
 701