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