git.sesse.net Git - ffmpeg/blob - libavfilter/avfiltergraph.c

   1 /*
   2  * filter graphs
   3  * Copyright (c) 2008 Vitor Sessak
   4  * Copyright (c) 2007 Bobby Bingham
   5  *
   6  * This file is part of Libav.
   7  *
   8  * Libav is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * Libav is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with Libav; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include <ctype.h>
  24 #include <string.h>
  25
  26 #include "avfilter.h"
  27 #include "avfiltergraph.h"
  28 #include "formats.h"
  29 #include "internal.h"
  30
  31 #include "libavutil/audioconvert.h"
  32 #include "libavutil/log.h"
  33
  34 static const AVClass filtergraph_class = {
  35     .class_name = "AVFilterGraph",
  36     .item_name  = av_default_item_name,
  37     .version    = LIBAVUTIL_VERSION_INT,
  38 };
  39
  40 AVFilterGraph *avfilter_graph_alloc(void)
  41 {
  42     AVFilterGraph *ret = av_mallocz(sizeof(AVFilterGraph));
  43     if (!ret)
  44         return NULL;
  45 #if FF_API_GRAPH_AVCLASS
  46     ret->av_class = &filtergraph_class;
  47 #endif
  48     return ret;
  49 }
  50
  51 void avfilter_graph_free(AVFilterGraph **graph)
  52 {
  53     if (!*graph)
  54         return;
  55     for (; (*graph)->filter_count > 0; (*graph)->filter_count--)
  56         avfilter_free((*graph)->filters[(*graph)->filter_count - 1]);
  57     av_freep(&(*graph)->scale_sws_opts);
  58     av_freep(&(*graph)->filters);
  59     av_freep(graph);
  60 }
  61
  62 int avfilter_graph_add_filter(AVFilterGraph *graph, AVFilterContext *filter)
  63 {
  64     AVFilterContext **filters = av_realloc(graph->filters,
  65                                            sizeof(AVFilterContext*) * (graph->filter_count+1));
  66     if (!filters)
  67         return AVERROR(ENOMEM);
  68
  69     graph->filters = filters;
  70     graph->filters[graph->filter_count++] = filter;
  71
  72     return 0;
  73 }
  74
  75 int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
  76                                  const char *name, const char *args, void *opaque,
  77                                  AVFilterGraph *graph_ctx)
  78 {
  79     int ret;
  80
  81     if ((ret = avfilter_open(filt_ctx, filt, name)) < 0)
  82         goto fail;
  83     if ((ret = avfilter_init_filter(*filt_ctx, args, opaque)) < 0)
  84         goto fail;
  85     if ((ret = avfilter_graph_add_filter(graph_ctx, *filt_ctx)) < 0)
  86         goto fail;
  87     return 0;
  88
  89 fail:
  90     if (*filt_ctx)
  91         avfilter_free(*filt_ctx);
  92     *filt_ctx = NULL;
  93     return ret;
  94 }
  95
  96 int ff_avfilter_graph_check_validity(AVFilterGraph *graph, AVClass *log_ctx)
  97 {
  98     AVFilterContext *filt;
  99     int i, j;
 100
 101     for (i = 0; i < graph->filter_count; i++) {
 102         filt = graph->filters[i];
 103
 104         for (j = 0; j < filt->input_count; j++) {
 105             if (!filt->inputs[j] || !filt->inputs[j]->src) {
 106                 av_log(log_ctx, AV_LOG_ERROR,
 107                        "Input pad \"%s\" for the filter \"%s\" of type \"%s\" not connected to any source\n",
 108                        filt->input_pads[j].name, filt->name, filt->filter->name);
 109                 return AVERROR(EINVAL);
 110             }
 111         }
 112
 113         for (j = 0; j < filt->output_count; j++) {
 114             if (!filt->outputs[j] || !filt->outputs[j]->dst) {
 115                 av_log(log_ctx, AV_LOG_ERROR,
 116                        "Output pad \"%s\" for the filter \"%s\" of type \"%s\" not connected to any destination\n",
 117                        filt->output_pads[j].name, filt->name, filt->filter->name);
 118                 return AVERROR(EINVAL);
 119             }
 120         }
 121     }
 122
 123     return 0;
 124 }
 125
 126 int ff_avfilter_graph_config_links(AVFilterGraph *graph, AVClass *log_ctx)
 127 {
 128     AVFilterContext *filt;
 129     int i, ret;
 130
 131     for (i=0; i < graph->filter_count; i++) {
 132         filt = graph->filters[i];
 133
 134         if (!filt->output_count) {
 135             if ((ret = avfilter_config_links(filt)))
 136                 return ret;
 137         }
 138     }
 139
 140     return 0;
 141 }
 142
 143 AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name)
 144 {
 145     int i;
 146
 147     for (i = 0; i < graph->filter_count; i++)
 148         if (graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
 149             return graph->filters[i];
 150
 151     return NULL;
 152 }
 153
 154 static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
 155 {
 156     int i, j, ret;
 157     int scaler_count = 0, resampler_count = 0;
 158
 159     /* ask all the sub-filters for their supported media formats */
 160     for (i = 0; i < graph->filter_count; i++) {
 161         if (graph->filters[i]->filter->query_formats)
 162             graph->filters[i]->filter->query_formats(graph->filters[i]);
 163         else
 164             avfilter_default_query_formats(graph->filters[i]);
 165     }
 166
 167     /* go through and merge as many format lists as possible */
 168     for (i = 0; i < graph->filter_count; i++) {
 169         AVFilterContext *filter = graph->filters[i];
 170
 171         for (j = 0; j < filter->input_count; j++) {
 172             AVFilterLink *link = filter->inputs[j];
 173             int convert_needed = 0;
 174
 175             if (!link)
 176                 continue;
 177
 178             if (link->in_formats != link->out_formats &&
 179                 !avfilter_merge_formats(link->in_formats,
 180                                         link->out_formats))
 181                 convert_needed = 1;
 182             if (link->type == AVMEDIA_TYPE_AUDIO) {
 183                 if (link->in_channel_layouts != link->out_channel_layouts &&
 184                     !ff_merge_channel_layouts(link->in_channel_layouts,
 185                                               link->out_channel_layouts))
 186                     convert_needed = 1;
 187                 if (link->in_samplerates != link->out_samplerates &&
 188                     !ff_merge_samplerates(link->in_samplerates,
 189                                           link->out_samplerates))
 190                     convert_needed = 1;
 191             }
 192
 193             if (convert_needed) {
 194                     AVFilterContext *convert;
 195                     AVFilter *filter;
 196                     AVFilterLink *inlink, *outlink;
 197                     char scale_args[256];
 198                     char inst_name[30];
 199
 200                     /* couldn't merge format lists. auto-insert conversion filter */
 201                     switch (link->type) {
 202                     case AVMEDIA_TYPE_VIDEO:
 203                         snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d",
 204                                  scaler_count++);
 205                         snprintf(scale_args, sizeof(scale_args), "0:0:%s", graph->scale_sws_opts);
 206                         if ((ret = avfilter_graph_create_filter(&convert,
 207                                                                 avfilter_get_by_name("scale"),
 208                                                                 inst_name, scale_args, NULL,
 209                                                                 graph)) < 0)
 210                             return ret;
 211                         break;
 212                     case AVMEDIA_TYPE_AUDIO:
 213                         if (!(filter = avfilter_get_by_name("resample"))) {
 214                             av_log(log_ctx, AV_LOG_ERROR, "'resample' filter "
 215                                    "not present, cannot convert audio formats.\n");
 216                             return AVERROR(EINVAL);
 217                         }
 218
 219                         snprintf(inst_name, sizeof(inst_name), "auto-inserted resampler %d",
 220                                  resampler_count++);
 221                         if ((ret = avfilter_graph_create_filter(&convert,
 222                                                                 avfilter_get_by_name("resample"),
 223                                                                 inst_name, NULL, NULL, graph)) < 0)
 224                             return ret;
 225                         break;
 226                     default:
 227                         return AVERROR(EINVAL);
 228                     }
 229
 230                     if ((ret = avfilter_insert_filter(link, convert, 0, 0)) < 0)
 231                         return ret;
 232
 233                     convert->filter->query_formats(convert);
 234                     inlink  = convert->inputs[0];
 235                     outlink = convert->outputs[0];
 236                     if (!avfilter_merge_formats( inlink->in_formats,  inlink->out_formats) ||
 237                         !avfilter_merge_formats(outlink->in_formats, outlink->out_formats))
 238                         ret |= AVERROR(ENOSYS);
 239                     if (inlink->type == AVMEDIA_TYPE_AUDIO &&
 240                         (!ff_merge_samplerates(inlink->in_samplerates,
 241                                                inlink->out_samplerates) ||
 242                          !ff_merge_channel_layouts(inlink->in_channel_layouts,
 243                                                    inlink->out_channel_layouts)))
 244                         ret |= AVERROR(ENOSYS);
 245                     if (outlink->type == AVMEDIA_TYPE_AUDIO &&
 246                         (!ff_merge_samplerates(outlink->in_samplerates,
 247                                                outlink->out_samplerates) ||
 248                          !ff_merge_channel_layouts(outlink->in_channel_layouts,
 249                                                    outlink->out_channel_layouts)))
 250                         ret |= AVERROR(ENOSYS);
 251
 252                     if (ret < 0) {
 253                         av_log(log_ctx, AV_LOG_ERROR,
 254                                "Impossible to convert between the formats supported by the filter "
 255                                "'%s' and the filter '%s'\n", link->src->name, link->dst->name);
 256                         return ret;
 257                     }
 258             }
 259         }
 260     }
 261
 262     return 0;
 263 }
 264
 265 static int pick_format(AVFilterLink *link)
 266 {
 267     if (!link || !link->in_formats)
 268         return 0;
 269
 270     link->in_formats->format_count = 1;
 271     link->format = link->in_formats->formats[0];
 272
 273     if (link->type == AVMEDIA_TYPE_AUDIO) {
 274         if (!link->in_samplerates->format_count) {
 275             av_log(link->src, AV_LOG_ERROR, "Cannot select sample rate for"
 276                    " the link between filters %s and %s.\n", link->src->name,
 277                    link->dst->name);
 278             return AVERROR(EINVAL);
 279         }
 280         link->in_samplerates->format_count = 1;
 281         link->sample_rate = link->in_samplerates->formats[0];
 282
 283         if (!link->in_channel_layouts->nb_channel_layouts) {
 284             av_log(link->src, AV_LOG_ERROR, "Cannot select channel layout for"
 285                    "the link between filters %s and %s.\n", link->src->name,
 286                    link->dst->name);
 287             return AVERROR(EINVAL);
 288         }
 289         link->in_channel_layouts->nb_channel_layouts = 1;
 290         link->channel_layout = link->in_channel_layouts->channel_layouts[0];
 291     }
 292
 293     avfilter_formats_unref(&link->in_formats);
 294     avfilter_formats_unref(&link->out_formats);
 295     avfilter_formats_unref(&link->in_samplerates);
 296     avfilter_formats_unref(&link->out_samplerates);
 297     ff_channel_layouts_unref(&link->in_channel_layouts);
 298     ff_channel_layouts_unref(&link->out_channel_layouts);
 299
 300     return 0;
 301 }
 302
 303 #define REDUCE_FORMATS(fmt_type, list_type, list, var, nb, add_format) \
 304 do {                                                                   \
 305     for (i = 0; i < filter->input_count; i++) {                        \
 306         AVFilterLink *link = filter->inputs[i];                        \
 307         fmt_type fmt;                                                  \
 308                                                                        \
 309         if (!link->out_ ## list || link->out_ ## list->nb != 1)        \
 310             continue;                                                  \
 311         fmt = link->out_ ## list->var[0];                              \
 312                                                                        \
 313         for (j = 0; j < filter->output_count; j++) {                   \
 314             AVFilterLink *out_link = filter->outputs[j];               \
 315             list_type *fmts;                                           \
 316                                                                        \
 317             if (link->type != out_link->type ||                        \
 318                 out_link->in_ ## list->nb == 1)                        \
 319                 continue;                                              \
 320             fmts = out_link->in_ ## list;                              \
 321                                                                        \
 322             if (!out_link->in_ ## list->nb) {                          \
 323                 add_format(&out_link->in_ ##list, fmt);                \
 324                 break;                                                 \
 325             }                                                          \
 326                                                                        \
 327             for (k = 0; k < out_link->in_ ## list->nb; k++)            \
 328                 if (fmts->var[k] == fmt) {                             \
 329                     fmts->var[0]  = fmt;                               \
 330                     fmts->nb = 1;                                      \
 331                     ret = 1;                                           \
 332                     break;                                             \
 333                 }                                                      \
 334         }                                                              \
 335     }                                                                  \
 336 } while (0)
 337
 338 static int reduce_formats_on_filter(AVFilterContext *filter)
 339 {
 340     int i, j, k, ret = 0;
 341
 342     REDUCE_FORMATS(int,      AVFilterFormats,        formats,         formats,
 343                    format_count, avfilter_add_format);
 344     REDUCE_FORMATS(int,      AVFilterFormats,        samplerates,     formats,
 345                    format_count, avfilter_add_format);
 346     REDUCE_FORMATS(uint64_t, AVFilterChannelLayouts, channel_layouts,
 347                    channel_layouts, nb_channel_layouts, ff_add_channel_layout);
 348
 349     return ret;
 350 }
 351
 352 static void reduce_formats(AVFilterGraph *graph)
 353 {
 354     int i, reduced;
 355
 356     do {
 357         reduced = 0;
 358
 359         for (i = 0; i < graph->filter_count; i++)
 360             reduced |= reduce_formats_on_filter(graph->filters[i]);
 361     } while (reduced);
 362 }
 363
 364 static void swap_samplerates_on_filter(AVFilterContext *filter)
 365 {
 366     AVFilterLink *link = NULL;
 367     int sample_rate;
 368     int i, j;
 369
 370     for (i = 0; i < filter->input_count; i++) {
 371         link = filter->inputs[i];
 372
 373         if (link->type == AVMEDIA_TYPE_AUDIO &&
 374             link->out_samplerates->format_count == 1)
 375             break;
 376     }
 377     if (i == filter->input_count)
 378         return;
 379
 380     sample_rate = link->out_samplerates->formats[0];
 381
 382     for (i = 0; i < filter->output_count; i++) {
 383         AVFilterLink *outlink = filter->outputs[i];
 384         int best_idx, best_diff = INT_MAX;
 385
 386         if (outlink->type != AVMEDIA_TYPE_AUDIO ||
 387             outlink->in_samplerates->format_count < 2)
 388             continue;
 389
 390         for (j = 0; j < outlink->in_samplerates->format_count; j++) {
 391             int diff = abs(sample_rate - outlink->in_samplerates->formats[j]);
 392
 393             if (diff < best_diff) {
 394                 best_diff = diff;
 395                 best_idx  = j;
 396             }
 397         }
 398         FFSWAP(int, outlink->in_samplerates->formats[0],
 399                outlink->in_samplerates->formats[best_idx]);
 400     }
 401 }
 402
 403 static void swap_samplerates(AVFilterGraph *graph)
 404 {
 405     int i;
 406
 407     for (i = 0; i < graph->filter_count; i++)
 408         swap_samplerates_on_filter(graph->filters[i]);
 409 }
 410
 411 static void swap_channel_layouts_on_filter(AVFilterContext *filter)
 412 {
 413     AVFilterLink *link = NULL;
 414     uint64_t chlayout;
 415     int i, j;
 416
 417     for (i = 0; i < filter->input_count; i++) {
 418         link = filter->inputs[i];
 419
 420         if (link->type == AVMEDIA_TYPE_AUDIO &&
 421             link->out_channel_layouts->nb_channel_layouts == 1)
 422             break;
 423     }
 424     if (i == filter->input_count)
 425         return;
 426
 427     chlayout = link->out_channel_layouts->channel_layouts[0];
 428
 429     for (i = 0; i < filter->output_count; i++) {
 430         AVFilterLink *outlink = filter->outputs[i];
 431         int best_idx, best_score = INT_MIN;
 432
 433         if (outlink->type != AVMEDIA_TYPE_AUDIO ||
 434             outlink->in_channel_layouts->nb_channel_layouts < 2)
 435             continue;
 436
 437         for (j = 0; j < outlink->in_channel_layouts->nb_channel_layouts; j++) {
 438             uint64_t out_chlayout = outlink->in_channel_layouts->channel_layouts[j];
 439             int matched_channels  = av_get_channel_layout_nb_channels(chlayout &
 440                                                                       out_chlayout);
 441             int extra_channels     = av_get_channel_layout_nb_channels(out_chlayout &
 442                                                                        (~chlayout));
 443             int score = matched_channels - extra_channels;
 444
 445             if (score > best_score) {
 446                 best_score = score;
 447                 best_idx   = j;
 448             }
 449         }
 450         FFSWAP(uint64_t, outlink->in_channel_layouts->channel_layouts[0],
 451                outlink->in_channel_layouts->channel_layouts[best_idx]);
 452     }
 453
 454 }
 455
 456 static void swap_channel_layouts(AVFilterGraph *graph)
 457 {
 458     int i;
 459
 460     for (i = 0; i < graph->filter_count; i++)
 461         swap_channel_layouts_on_filter(graph->filters[i]);
 462 }
 463
 464 static int pick_formats(AVFilterGraph *graph)
 465 {
 466     int i, j, ret;
 467
 468     for (i = 0; i < graph->filter_count; i++) {
 469         AVFilterContext *filter = graph->filters[i];
 470
 471         for (j = 0; j < filter->input_count; j++)
 472             if ((ret = pick_format(filter->inputs[j])) < 0)
 473                 return ret;
 474         for (j = 0; j < filter->output_count; j++)
 475             if ((ret = pick_format(filter->outputs[j])) < 0)
 476                 return ret;
 477     }
 478     return 0;
 479 }
 480
 481 int ff_avfilter_graph_config_formats(AVFilterGraph *graph, AVClass *log_ctx)
 482 {
 483     int ret;
 484
 485     /* find supported formats from sub-filters, and merge along links */
 486     if ((ret = query_formats(graph, log_ctx)) < 0)
 487         return ret;
 488
 489     /* Once everything is merged, it's possible that we'll still have
 490      * multiple valid media format choices. We try to minimize the amount
 491      * of format conversion inside filters */
 492     reduce_formats(graph);
 493
 494     /* for audio filters, ensure the best sample rate and channel layout
 495      * is selected */
 496     swap_samplerates(graph);
 497     swap_channel_layouts(graph);
 498
 499     if ((ret = pick_formats(graph)) < 0)
 500         return ret;
 501
 502     return 0;
 503 }
 504
 505 int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
 506 {
 507     int ret;
 508
 509     if ((ret = ff_avfilter_graph_check_validity(graphctx, log_ctx)))
 510         return ret;
 511     if ((ret = ff_avfilter_graph_config_formats(graphctx, log_ctx)))
 512         return ret;
 513     if ((ret = ff_avfilter_graph_config_links(graphctx, log_ctx)))
 514         return ret;
 515
 516     return 0;
 517 }