libavfilter/avfiltergraph.c

   1 /*
   2  * Filter graphs
   3  * copyright (c) 2007 Bobby Bingham
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <string.h>
  23 #include <stddef.h>
  24
  25 #include "avstring.h"
  26 #include "avfilter.h"
  27 #include "avfiltergraph.h"
  28
  29 #include "allfilters.h"
  30
  31 typedef struct AVFilterGraph {
  32     unsigned filter_count;
  33     AVFilterContext **filters;
  34
  35     /** fake filters to handle links to internal filters */
  36     AVFilterContext *link_filter_in;
  37     AVFilterContext *link_filter_out;
  38 } GraphContext;
  39
  40 typedef struct {
  41     AVFilterContext *graph;
  42 } GraphLinkContext;
  43
  44 static int link_init(AVFilterContext *ctx, const char *args, void *opaque)
  45 {
  46     GraphLinkContext *linkctx = ctx->priv;
  47     linkctx->graph = opaque;
  48     return !opaque;
  49 }
  50
  51 /**
  52  * Given the link between the dummy filter and an internal filter whose input
  53  * is being exported outside the graph, this returns the externally visible
  54  * link
  55  */
  56 static inline AVFilterLink *get_extern_input_link(AVFilterLink *link)
  57 {
  58     GraphLinkContext *lctx = link->src->priv;
  59     return lctx->graph->inputs[link->srcpad];
  60 }
  61
  62 /** request a frame from a filter providing input to the graph */
  63 static int link_in_request_frame(AVFilterLink *link)
  64 {
  65     AVFilterLink *link2 = get_extern_input_link(link);
  66
  67     if(!link2)
  68         return -1;
  69     return avfilter_request_frame(link2);
  70 }
  71
  72 static int link_in_config_props(AVFilterLink *link)
  73 {
  74     AVFilterLink *link2 = get_extern_input_link(link);
  75     int (*config_props)(AVFilterLink *);
  76     int ret;
  77
  78     if(!link2)
  79         return -1;
  80     if(!(config_props = link2->src->output_pads[link2->srcpad].config_props))
  81         config_props = avfilter_default_config_output_link;
  82     ret = config_props(link2);
  83
  84     link->w = link2->w;
  85     link->h = link2->h;
  86
  87     return ret;
  88 }
  89
  90 /**
  91  * Given the link between the dummy filter and an internal filter whose input
  92  * is being exported outside the graph, this returns the externally visible
  93  * link
  94  */
  95 static inline AVFilterLink *get_extern_output_link(AVFilterLink *link)
  96 {
  97     GraphLinkContext *lctx = link->dst->priv;
  98     return lctx->graph->outputs[link->dstpad];
  99 }
 100
 101 static int link_out_config_props(AVFilterLink *link)
 102 {
 103     AVFilterLink *link2 = get_extern_output_link(link);
 104     int (*config_props)(AVFilterLink *);
 105
 106     if(!link2)
 107         return 0;
 108
 109     link2->w = link->w;
 110     link2->h = link->h;
 111
 112     if(!(config_props = link2->dst->input_pads[link2->dstpad].config_props))
 113         config_props = avfilter_default_config_input_link;
 114     return config_props(link2);
 115 }
 116
 117 static void link_out_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
 118 {
 119     AVFilterLink *link2 = get_extern_output_link(link);
 120
 121     if(!link2)
 122         avfilter_unref_pic(picref);
 123     else
 124         avfilter_start_frame(link2, picref);
 125 }
 126
 127 static void link_out_end_frame(AVFilterLink *link)
 128 {
 129     AVFilterLink *link2 = get_extern_output_link(link);
 130
 131     if(link2)
 132         avfilter_end_frame(link2);
 133 }
 134
 135 static AVFilterPicRef *link_out_get_video_buffer(AVFilterLink *link, int perms)
 136 {
 137     AVFilterLink *link2 = get_extern_output_link(link);
 138
 139     if(!link2)
 140         return NULL;
 141     else
 142         return avfilter_get_video_buffer(link2, perms);
 143 }
 144
 145 static void link_out_draw_slice(AVFilterLink *link, int y, int height)
 146 {
 147     AVFilterLink *link2 = get_extern_output_link(link);
 148
 149     if(link2)
 150         avfilter_draw_slice(link2, y, height);
 151 }
 152
 153 /** dummy filter used to help export filters pads outside the graph */
 154 static AVFilter vf_graph_dummy =
 155 {
 156     .name      = "graph_dummy",
 157     .author    = "Bobby Bingham",
 158
 159     .priv_size = sizeof(GraphLinkContext),
 160
 161     .init      = link_init,
 162
 163     .inputs    = (AVFilterPad[]) {{ .name = NULL, }},
 164     .outputs   = (AVFilterPad[]) {{ .name = NULL, }},
 165 };
 166
 167 static AVFilterLink *get_intern_input_link(AVFilterLink *link)
 168 {
 169     GraphContext *graph = link->dst->priv;
 170     return graph->link_filter_in->outputs[link->dstpad];
 171 }
 172
 173 static void graph_in_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
 174 {
 175     AVFilterLink *link2 = get_intern_input_link(link);
 176     if(link2)
 177         avfilter_start_frame(link2, picref);
 178 }
 179
 180 static void graph_in_end_frame(AVFilterLink *link)
 181 {
 182     AVFilterLink *link2 = get_intern_input_link(link);
 183     if(link2)
 184         avfilter_end_frame(link2);
 185 }
 186
 187 static AVFilterPicRef *graph_in_get_video_buffer(AVFilterLink *link, int perms)
 188 {
 189     AVFilterLink *link2 = get_intern_input_link(link);
 190     if(link2)
 191         return avfilter_get_video_buffer(link2, perms);
 192     return NULL;
 193 }
 194
 195 static void graph_in_draw_slice(AVFilterLink *link, int y, int height)
 196 {
 197     AVFilterLink *link2 = get_intern_input_link(link);
 198     if(link2)
 199         avfilter_draw_slice(link2, y, height);
 200 }
 201
 202 static int graph_in_config_props(AVFilterLink *link)
 203 {
 204     AVFilterLink *link2 = get_intern_input_link(link);
 205     int (*config_props)(AVFilterLink *);
 206
 207     if(!link2)
 208         return -1;
 209
 210     /* copy link properties over to the dummy internal link */
 211     link2->w = link->w;
 212     link2->h = link->h;
 213     link2->format = link->format;
 214
 215     if(!(config_props = link2->dst->input_pads[link2->dstpad].config_props))
 216         return 0;   /* FIXME? */
 217         //config_props = avfilter_default_config_input_link;
 218     return config_props(link2);
 219 }
 220
 221 static AVFilterLink *get_intern_output_link(AVFilterLink *link)
 222 {
 223     GraphContext *graph = link->src->priv;
 224     return graph->link_filter_out->inputs[link->srcpad];
 225 }
 226
 227 static int graph_out_request_frame(AVFilterLink *link)
 228 {
 229     AVFilterLink *link2 = get_intern_output_link(link);
 230
 231     if(link2)
 232         return avfilter_request_frame(link2);
 233     return -1;
 234 }
 235
 236 static int graph_out_config_props(AVFilterLink *link)
 237 {
 238     AVFilterLink *link2 = get_intern_output_link(link);
 239     int (*config_props)(AVFilterLink *);
 240     int ret;
 241
 242     if(!link2)
 243         return 0;
 244
 245     link2->w = link->w;
 246     link2->h = link->h;
 247     link2->format = link->format;
 248
 249     if(!(config_props = link2->src->output_pads[link2->srcpad].config_props))
 250         config_props = avfilter_default_config_output_link;
 251     ret = config_props(link2);
 252
 253     link->w = link2->w;
 254     link->h = link2->h;
 255     link->format = link2->format;
 256
 257     return ret;
 258 }
 259
 260 static int add_graph_input(AVFilterContext *gctx, AVFilterContext *filt, unsigned idx,
 261                            char *name)
 262 {
 263     GraphContext *graph = gctx->priv;
 264
 265     AVFilterPad graph_inpad =
 266     {
 267         .name             = name,
 268         .type             = AV_PAD_VIDEO,
 269         .start_frame      = graph_in_start_frame,
 270         .end_frame        = graph_in_end_frame,
 271         .get_video_buffer = graph_in_get_video_buffer,
 272         .draw_slice       = graph_in_draw_slice,
 273         .config_props     = graph_in_config_props,
 274         /* XXX */
 275     };
 276     AVFilterPad dummy_outpad =
 277     {
 278         .name          = NULL,          /* FIXME? */
 279         .type          = AV_PAD_VIDEO,
 280         .request_frame = link_in_request_frame,
 281         .config_props  = link_in_config_props,
 282     };
 283
 284     avfilter_insert_inpad (gctx, gctx->input_count, &graph_inpad);
 285     avfilter_insert_outpad(graph->link_filter_in, graph->link_filter_in->output_count,
 286                            &dummy_outpad);
 287     return avfilter_link(graph->link_filter_in,
 288                          graph->link_filter_in->output_count-1, filt, idx);
 289 }
 290
 291 static int add_graph_output(AVFilterContext *gctx, AVFilterContext *filt, unsigned idx,
 292                             char *name)
 293 {
 294     GraphContext *graph = gctx->priv;
 295
 296     AVFilterPad graph_outpad =
 297     {
 298         .name             = name,
 299         .type             = AV_PAD_VIDEO,
 300         .request_frame    = graph_out_request_frame,
 301         .config_props     = graph_out_config_props,
 302     };
 303     AVFilterPad dummy_inpad =
 304     {
 305         .name             = NULL,          /* FIXME? */
 306         .type             = AV_PAD_VIDEO,
 307         .start_frame      = link_out_start_frame,
 308         .end_frame        = link_out_end_frame,
 309         .draw_slice       = link_out_draw_slice,
 310         .get_video_buffer = link_out_get_video_buffer,
 311         .config_props     = link_out_config_props,
 312     };
 313
 314     avfilter_insert_outpad(gctx, gctx->output_count, &graph_outpad);
 315     avfilter_insert_inpad (graph->link_filter_out, graph->link_filter_out->input_count,
 316                            &dummy_inpad);
 317     return avfilter_link(filt, idx, graph->link_filter_out,
 318                          graph->link_filter_out->input_count-1);
 319 }
 320
 321 static void uninit(AVFilterContext *ctx)
 322 {
 323     GraphContext *graph = ctx->priv;
 324
 325     if(graph->link_filter_in) {
 326         avfilter_destroy(graph->link_filter_in);
 327         graph->link_filter_in = NULL;
 328     }
 329     if(graph->link_filter_out) {
 330         avfilter_destroy(graph->link_filter_out);
 331         graph->link_filter_out = NULL;
 332     }
 333     for(; graph->filter_count > 0; graph->filter_count --)
 334         avfilter_destroy(graph->filters[graph->filter_count - 1]);
 335     av_freep(&graph->filters);
 336 }
 337
 338 /* TODO: insert in sorted order */
 339 void avfilter_graph_add_filter(AVFilterContext *graphctx, AVFilterContext *filter)
 340 {
 341     GraphContext *graph = graphctx->priv;
 342
 343     graph->filters = av_realloc(graph->filters,
 344                                 sizeof(AVFilterContext*) * ++graph->filter_count);
 345     graph->filters[graph->filter_count - 1] = filter;
 346 }
 347
 348 /* search intelligently, once we insert in order */
 349 AVFilterContext *avfilter_graph_get_filter(AVFilterContext *ctx, char *name)
 350 {
 351     GraphContext *graph = ctx->priv;
 352     int i;
 353
 354     if(!name)
 355         return NULL;
 356
 357     for(i = 0; i < graph->filter_count; i ++)
 358         if(graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
 359             return graph->filters[i];
 360
 361     return NULL;
 362 }
 363
 364 static int query_formats(AVFilterContext *graphctx)
 365 {
 366     GraphContext *graph = graphctx->priv;
 367     AVFilterContext *linkfiltin  = graph->link_filter_in;
 368     AVFilterContext *linkfiltout = graph->link_filter_out;
 369     int i, j;
 370
 371     /* ask all the sub-filters for their supported colorspaces */
 372     for(i = 0; i < graph->filter_count; i ++) {
 373         if(graph->filters[i]->filter->query_formats)
 374             graph->filters[i]->filter->query_formats(graph->filters[i]);
 375         else
 376             avfilter_default_query_formats(graph->filters[i]);
 377     }
 378
 379     /* use these formats on our exported links */
 380     for(i = 0; i < linkfiltout->input_count; i ++) {
 381         avfilter_formats_ref( linkfiltout->inputs[i]->in_formats,
 382                              &linkfiltout->inputs[i]->out_formats);
 383
 384         if(graphctx->outputs[i])
 385             avfilter_formats_ref(linkfiltout->inputs[i]->in_formats,
 386                                  &graphctx->outputs[i]->in_formats);
 387     }
 388     for(i = 0; i < linkfiltin->output_count; i ++) {
 389         avfilter_formats_ref( linkfiltin->outputs[i]->out_formats,
 390                              &linkfiltin->outputs[i]->in_formats);
 391
 392         if(graphctx->inputs[i])
 393             avfilter_formats_ref(linkfiltin->outputs[i]->out_formats,
 394                                  &graphctx-> inputs[i]->out_formats);
 395     }
 396
 397     /* go through and merge as many format lists as possible */
 398     for(i = 0; i < graph->filter_count; i ++) {
 399         AVFilterContext *filter = graph->filters[i];
 400
 401         for(j = 0; j < filter->input_count; j ++) {
 402             AVFilterLink *link;
 403             if(!(link = filter->inputs[j]))
 404                 continue;
 405             if(link->in_formats != link->out_formats) {
 406                 if(!avfilter_merge_formats(link->in_formats,
 407                                            link->out_formats)) {
 408                     /* couldn't merge format lists. auto-insert scale filter */
 409                     AVFilterContext *scale;
 410
 411                     if(!(scale = avfilter_open(&avfilter_vf_scale, NULL)))
 412                         return -1;
 413                     if(scale->filter->init(scale, NULL, NULL) ||
 414                        avfilter_insert_filter(link, scale, 0, 0)) {
 415                         avfilter_destroy(scale);
 416                         return -1;
 417                     }
 418
 419                     avfilter_graph_add_filter(graphctx, scale);
 420                     scale->filter->query_formats(scale);
 421                     if(!avfilter_merge_formats(scale-> inputs[0]->in_formats,
 422                                               scale-> inputs[0]->out_formats) ||
 423                        !avfilter_merge_formats(scale->outputs[0]->in_formats,
 424                                               scale->outputs[0]->out_formats))
 425                         return -1;
 426                 }
 427             }
 428         }
 429     }
 430
 431     return 0;
 432 }
 433
 434 static void pick_format(AVFilterLink *link)
 435 {
 436     if(!link || !link->in_formats)
 437         return;
 438
 439     link->in_formats->format_count = 1;
 440     link->format = link->in_formats->formats[0];
 441
 442     avfilter_formats_unref(&link->in_formats);
 443     avfilter_formats_unref(&link->out_formats);
 444 }
 445
 446 static void pick_formats(GraphContext *graph)
 447 {
 448     int i, j;
 449
 450     for(i = 0; i < graph->filter_count; i ++) {
 451         AVFilterContext *filter = graph->filters[i];
 452
 453         if(filter->filter == &avfilter_vf_graph     ||
 454            filter->filter == &avfilter_vf_graphfile ||
 455            filter->filter == &avfilter_vf_graphdesc)
 456             pick_formats(filter->priv);
 457
 458         for(j = 0; j < filter->input_count; j ++)
 459             pick_format(filter->inputs[j]);
 460         for(j = 0; j < filter->output_count; j ++)
 461             pick_format(filter->outputs[j]);
 462     }
 463 }
 464
 465 int avfilter_graph_config_formats(AVFilterContext *graphctx)
 466 {
 467     GraphContext *graph = graphctx->priv;
 468
 469     /* Find supported formats from sub-filters, and merge along links */
 470     if(query_formats(graphctx))
 471         return -1;
 472
 473     /* Once everything is merged, it's possible that we'll still have
 474      * multiple valid choices of colorspace. We pick the first one. */
 475     pick_formats(graph);
 476
 477     return 0;
 478 }
 479
 480 int avfilter_graph_config_links(AVFilterContext *graphctx)
 481 {
 482     GraphContext *graph = graphctx->priv;
 483     int i, j;
 484
 485     for(i = 0; i < graph->filter_count; i ++) {
 486         for(j = 0; j < graph->filters[i]->input_count; j ++) {
 487             /* ensure that graphs contained within graphs are configured */
 488             if((graph->filters[i]->filter == &avfilter_vf_graph     ||
 489                 graph->filters[i]->filter == &avfilter_vf_graphfile ||
 490                 graph->filters[i]->filter == &avfilter_vf_graphdesc) &&
 491                 avfilter_graph_config_links(graph->filters[i]))
 492                 return -1;
 493             if(avfilter_config_link(graph->filters[i]->inputs[j]))
 494                 return -1;
 495         }
 496     }
 497
 498     return 0;
 499 }
 500
 501 static int graph_load_from_desc(AVFilterContext *ctx, AVFilterGraphDesc *desc)
 502 {
 503     AVFilterGraphDescFilter *curfilt;
 504     AVFilterGraphDescLink   *curlink;
 505     AVFilterGraphDescExport *curpad;
 506     AVFilterContext *filt, *filtb;
 507
 508     AVFilter *filterdef;
 509
 510     /* create all filters */
 511     for(curfilt = desc->filters; curfilt; curfilt = curfilt->next) {
 512         if(!(filterdef = avfilter_get_by_name(curfilt->filter)) ||
 513            !(filt = avfilter_open(filterdef, curfilt->name))) {
 514             av_log(ctx, AV_LOG_ERROR, "error creating filter\n");
 515             goto fail;
 516         }
 517         avfilter_graph_add_filter(ctx, filt);
 518         if(avfilter_init_filter(filt, curfilt->args, NULL)) {
 519             av_log(ctx, AV_LOG_ERROR, "error initializing filter\n");
 520             goto fail;
 521         }
 522     }
 523
 524     /* create all links */
 525     for(curlink = desc->links; curlink; curlink = curlink->next) {
 526         if(!(filt = avfilter_graph_get_filter(ctx, curlink->src))) {
 527             av_log(ctx, AV_LOG_ERROR, "link source does not exist in graph\n");
 528             goto fail;
 529         }
 530         if(!(filtb = avfilter_graph_get_filter(ctx, curlink->dst))) {
 531             av_log(ctx, AV_LOG_ERROR, "link destination does not exist in graph\n");
 532             goto fail;
 533         }
 534         if(avfilter_link(filt, curlink->srcpad, filtb, curlink->dstpad)) {
 535             av_log(ctx, AV_LOG_ERROR, "cannot create link between source and destination filters\n");
 536             goto fail;
 537         }
 538     }
 539
 540     /* export all input pads */
 541     for(curpad = desc->inputs; curpad; curpad = curpad->next) {
 542         if(!(filt = avfilter_graph_get_filter(ctx, curpad->filter))) {
 543             av_log(ctx, AV_LOG_ERROR, "filter owning exported pad does not exist\n");
 544             goto fail;
 545         }
 546         add_graph_input(ctx, filt, curpad->pad, curpad->name);
 547     }
 548
 549     /* export all output pads */
 550     for(curpad = desc->outputs; curpad; curpad = curpad->next) {
 551         if(!(filt = avfilter_graph_get_filter(ctx, curpad->filter))) {
 552             av_log(ctx, AV_LOG_ERROR, "filter owning exported pad does not exist\n");
 553             goto fail;
 554         }
 555         add_graph_output(ctx, filt, curpad->pad, curpad->name);
 556     }
 557
 558     return 0;
 559
 560 fail:
 561     uninit(ctx);
 562     return -1;
 563 }
 564
 565 static int init(AVFilterContext *ctx, const char *args, void *opaque)
 566 {
 567     GraphContext *gctx = ctx->priv;
 568     AVFilterGraphDesc *desc;
 569     int ret;
 570
 571     if(!(gctx->link_filter_in = avfilter_open(&vf_graph_dummy, NULL)))
 572         return -1;
 573     if(avfilter_init_filter(gctx->link_filter_in, NULL, ctx))
 574         goto fail;
 575     if(!(gctx->link_filter_out = avfilter_open(&vf_graph_dummy, NULL)))
 576         goto fail;
 577     if(avfilter_init_filter(gctx->link_filter_out, NULL, ctx))
 578         goto fail;
 579
 580     if(!args)
 581         return 0;
 582
 583     if(!(desc = avfilter_graph_parse_chain(args)))
 584         goto fail;
 585
 586     ret = graph_load_from_desc(ctx, desc);
 587     avfilter_graph_free_desc(desc);
 588     return ret;
 589
 590 fail:
 591     avfilter_destroy(gctx->link_filter_in);
 592     if(gctx->link_filter_out)
 593         avfilter_destroy(gctx->link_filter_out);
 594     return -1;
 595 }
 596
 597 AVFilter avfilter_vf_graph =
 598 {
 599     .name      = "graph",
 600     .author    = "Bobby Bingham",
 601
 602     .priv_size = sizeof(GraphContext),
 603
 604     .init      = init,
 605     .uninit    = uninit,
 606
 607     .query_formats = query_formats,
 608
 609     .inputs    = (AVFilterPad[]) {{ .name = NULL, }},
 610     .outputs   = (AVFilterPad[]) {{ .name = NULL, }},
 611 };
 612
 613 static int init_desc(AVFilterContext *ctx, const char *args, void *opaque)
 614 {
 615     GraphContext *gctx = ctx->priv;
 616
 617     if(!opaque)
 618         return -1;
 619
 620     if(!(gctx->link_filter_in = avfilter_open(&vf_graph_dummy, NULL)))
 621         return -1;
 622     if(avfilter_init_filter(gctx->link_filter_in, NULL, ctx))
 623         goto fail;
 624     if(!(gctx->link_filter_out = avfilter_open(&vf_graph_dummy, NULL)))
 625         goto fail;
 626     if(avfilter_init_filter(gctx->link_filter_out, NULL, ctx))
 627         goto fail;
 628
 629     return graph_load_from_desc(ctx, opaque);
 630
 631 fail:
 632     avfilter_destroy(gctx->link_filter_in);
 633     if(gctx->link_filter_out)
 634         avfilter_destroy(gctx->link_filter_out);
 635     return -1;
 636 }
 637
 638 AVFilter avfilter_vf_graphdesc =
 639 {
 640     .name      = "graph_desc",
 641     .author    = "Bobby Bingham",
 642
 643     .priv_size = sizeof(GraphContext),
 644
 645     .init      = init_desc,
 646     .uninit    = uninit,
 647
 648     .query_formats = query_formats,
 649
 650     .inputs    = (AVFilterPad[]) {{ .name = NULL, }},
 651     .outputs   = (AVFilterPad[]) {{ .name = NULL, }},
 652 };
 653
 654 static int init_file(AVFilterContext *ctx, const char *args, void *opaque)
 655 {
 656     AVFilterGraphDesc *desc;
 657     int ret;
 658
 659     if(!args)
 660         return -1;
 661     if(!(desc = avfilter_graph_load_desc(args)))
 662         return -1;
 663
 664     ret = init_desc(ctx, NULL, desc);
 665     avfilter_graph_free_desc(desc);
 666     return ret;
 667 }
 668
 669 AVFilter avfilter_vf_graphfile =
 670 {
 671     .name      = "graph_file",
 672     .author    = "Bobby Bingham",
 673
 674     .priv_size = sizeof(GraphContext),
 675
 676     .init      = init_file,
 677     .uninit    = uninit,
 678
 679     .query_formats = query_formats,
 680
 681     .inputs    = (AVFilterPad[]) {{ .name = NULL, }},
 682     .outputs   = (AVFilterPad[]) {{ .name = NULL, }},
 683 };
 684