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
  73 static int link_in_poll_frame(AVFilterLink *link)
  74 {
  75     AVFilterLink *link2 = get_extern_input_link(link);
  76     if(!link2)
  77         return -1;
  78     return avfilter_poll_frame(link2);
  79 }
  80
  81 static int link_in_config_props(AVFilterLink *link)
  82 {
  83     AVFilterLink *link2 = get_extern_input_link(link);
  84     int (*config_props)(AVFilterLink *);
  85     int ret;
  86
  87     if(!link2)
  88         return -1;
  89     if(!(config_props = link2->src->output_pads[link2->srcpad].config_props))
  90         config_props = avfilter_default_config_output_link;
  91     ret = config_props(link2);
  92
  93     link->w = link2->w;
  94     link->h = link2->h;
  95
  96     return ret;
  97 }
  98
  99 /**
 100  * Given the link between the dummy filter and an internal filter whose input
 101  * is being exported outside the graph, this returns the externally visible
 102  * link.
 103  */
 104 static inline AVFilterLink *get_extern_output_link(AVFilterLink *link)
 105 {
 106     GraphLinkContext *lctx = link->dst->priv;
 107     return lctx->graph->outputs[link->dstpad];
 108 }
 109
 110 static int link_out_config_props(AVFilterLink *link)
 111 {
 112     AVFilterLink *link2 = get_extern_output_link(link);
 113
 114     if(!link2)
 115         return 0;
 116
 117     link2->w = link->w;
 118     link2->h = link->h;
 119
 120     return 0;
 121 }
 122
 123 static void link_out_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
 124 {
 125     AVFilterLink *link2 = get_extern_output_link(link);
 126
 127     if(!link2)
 128         avfilter_unref_pic(picref);
 129     else
 130         avfilter_start_frame(link2, picref);
 131 }
 132
 133 static void link_out_end_frame(AVFilterLink *link)
 134 {
 135     AVFilterLink *link2 = get_extern_output_link(link);
 136
 137     if(link2)
 138         avfilter_end_frame(link2);
 139 }
 140
 141 static AVFilterPicRef *link_out_get_video_buffer(AVFilterLink *link, int perms)
 142 {
 143     AVFilterLink *link2 = get_extern_output_link(link);
 144
 145     if(!link2)
 146         return NULL;
 147     else
 148         return avfilter_get_video_buffer(link2, perms);
 149 }
 150
 151 static void link_out_draw_slice(AVFilterLink *link, int y, int height)
 152 {
 153     AVFilterLink *link2 = get_extern_output_link(link);
 154
 155     if(link2)
 156         avfilter_draw_slice(link2, y, height);
 157 }
 158
 159 /** dummy filter used to help export filters pads outside the graph */
 160 static AVFilter vf_graph_dummy =
 161 {
 162     .name      = "graph_dummy",
 163     .author    = "Bobby Bingham",
 164
 165     .priv_size = sizeof(GraphLinkContext),
 166
 167     .init      = link_init,
 168
 169     .inputs    = (AVFilterPad[]) {{ .name = NULL, }},
 170     .outputs   = (AVFilterPad[]) {{ .name = NULL, }},
 171 };
 172
 173 static AVFilterLink *get_intern_input_link(AVFilterLink *link)
 174 {
 175     GraphContext *graph = link->dst->priv;
 176     return graph->link_filter_in->outputs[link->dstpad];
 177 }
 178
 179 static void graph_in_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
 180 {
 181     AVFilterLink *link2 = get_intern_input_link(link);
 182     if(link2)
 183         avfilter_start_frame(link2, picref);
 184 }
 185
 186 static void graph_in_end_frame(AVFilterLink *link)
 187 {
 188     AVFilterLink *link2 = get_intern_input_link(link);
 189     if(link2)
 190         avfilter_end_frame(link2);
 191 }
 192
 193 static AVFilterPicRef *graph_in_get_video_buffer(AVFilterLink *link, int perms)
 194 {
 195     AVFilterLink *link2 = get_intern_input_link(link);
 196     if(link2)
 197         return avfilter_get_video_buffer(link2, perms);
 198     return NULL;
 199 }
 200
 201 static void graph_in_draw_slice(AVFilterLink *link, int y, int height)
 202 {
 203     AVFilterLink *link2 = get_intern_input_link(link);
 204     if(link2)
 205         avfilter_draw_slice(link2, y, height);
 206 }
 207
 208 static int graph_in_config_props(AVFilterLink *link)
 209 {
 210     AVFilterLink *link2 = get_intern_input_link(link);
 211     int (*config_props)(AVFilterLink *);
 212     int ret;
 213
 214     if(!link2)
 215         return -1;
 216
 217     /* copy link properties over to the dummy internal link */
 218     link2->w = link->w;
 219     link2->h = link->h;
 220     link2->format = link->format;
 221
 222     if(!(config_props = link2->dst->input_pads[link2->dstpad].config_props))
 223         return 0;   /* FIXME? */
 224         //config_props = avfilter_default_config_input_link;
 225     if(!(ret = config_props(link2)))
 226         link2->init_state = AVLINK_INIT;
 227     else
 228         link2->init_state = AVLINK_STARTINIT;
 229
 230     return ret;
 231 }
 232
 233 static AVFilterLink *get_intern_output_link(AVFilterLink *link)
 234 {
 235     GraphContext *graph = link->src->priv;
 236     return graph->link_filter_out->inputs[link->srcpad];
 237 }
 238
 239 static int graph_out_request_frame(AVFilterLink *link)
 240 {
 241     AVFilterLink *link2 = get_intern_output_link(link);
 242
 243     if(link2)
 244         return avfilter_request_frame(link2);
 245     return -1;
 246 }
 247
 248 static int graph_out_poll_frame(AVFilterLink *link)
 249 {
 250     AVFilterLink *link2 = get_intern_output_link(link);
 251
 252     if(!link2)
 253         return -1;
 254
 255     return avfilter_poll_frame(link2);
 256 }
 257
 258 static int graph_out_config_props(AVFilterLink *link)
 259 {
 260     GraphContext *graph = link->src->priv;
 261     AVFilterLink *link2 = graph->link_filter_out->inputs[link->srcpad];
 262     int ret;
 263
 264     if((ret = avfilter_config_links(graph->link_filter_out)))
 265         return ret;
 266
 267     if(!link2)
 268         return 0;
 269
 270     link->w = link2->w;
 271     link->h = link2->h;
 272     link->format = link2->format;
 273
 274     return 0;
 275 }
 276
 277 static int add_graph_input(AVFilterContext *gctx, AVFilterContext *filt, unsigned idx,
 278                            char *name)
 279 {
 280     GraphContext *graph = gctx->priv;
 281
 282     AVFilterPad graph_inpad =
 283     {
 284         .name             = name,
 285         .type             = AV_PAD_VIDEO,
 286         .start_frame      = graph_in_start_frame,
 287         .end_frame        = graph_in_end_frame,
 288         .get_video_buffer = graph_in_get_video_buffer,
 289         .draw_slice       = graph_in_draw_slice,
 290         .config_props     = graph_in_config_props,
 291         /* XXX */
 292     };
 293     AVFilterPad dummy_outpad =
 294     {
 295         .name          = NULL,          /* FIXME? */
 296         .type          = AV_PAD_VIDEO,
 297         .request_frame = link_in_request_frame,
 298         .poll_frame    = link_in_poll_frame,
 299         .config_props  = link_in_config_props,
 300     };
 301
 302     avfilter_insert_inpad (gctx, gctx->input_count, &graph_inpad);
 303     avfilter_insert_outpad(graph->link_filter_in, graph->link_filter_in->output_count,
 304                            &dummy_outpad);
 305     return avfilter_link(graph->link_filter_in,
 306                          graph->link_filter_in->output_count-1, filt, idx);
 307 }
 308
 309 static int add_graph_output(AVFilterContext *gctx, AVFilterContext *filt, unsigned idx,
 310                             char *name)
 311 {
 312     GraphContext *graph = gctx->priv;
 313
 314     AVFilterPad graph_outpad =
 315     {
 316         .name             = name,
 317         .type             = AV_PAD_VIDEO,
 318         .request_frame    = graph_out_request_frame,
 319         .poll_frame       = graph_out_poll_frame,
 320         .config_props     = graph_out_config_props,
 321     };
 322     AVFilterPad dummy_inpad =
 323     {
 324         .name             = NULL,          /* FIXME? */
 325         .type             = AV_PAD_VIDEO,
 326         .start_frame      = link_out_start_frame,
 327         .end_frame        = link_out_end_frame,
 328         .draw_slice       = link_out_draw_slice,
 329         .get_video_buffer = link_out_get_video_buffer,
 330         .config_props     = link_out_config_props,
 331     };
 332
 333     avfilter_insert_outpad(gctx, gctx->output_count, &graph_outpad);
 334     avfilter_insert_inpad (graph->link_filter_out, graph->link_filter_out->input_count,
 335                            &dummy_inpad);
 336     return avfilter_link(filt, idx, graph->link_filter_out,
 337                          graph->link_filter_out->input_count-1);
 338 }
 339
 340 static void uninit(AVFilterContext *ctx)
 341 {
 342     GraphContext *graph = ctx->priv;
 343
 344     if(graph->link_filter_in) {
 345         avfilter_destroy(graph->link_filter_in);
 346         graph->link_filter_in = NULL;
 347     }
 348     if(graph->link_filter_out) {
 349         avfilter_destroy(graph->link_filter_out);
 350         graph->link_filter_out = NULL;
 351     }
 352     for(; graph->filter_count > 0; graph->filter_count --)
 353         avfilter_destroy(graph->filters[graph->filter_count - 1]);
 354     av_freep(&graph->filters);
 355 }
 356
 357 /* TODO: insert in sorted order */
 358 void avfilter_graph_add_filter(AVFilterContext *graphctx, AVFilterContext *filter)
 359 {
 360     GraphContext *graph = graphctx->priv;
 361
 362     graph->filters = av_realloc(graph->filters,
 363                                 sizeof(AVFilterContext*) * ++graph->filter_count);
 364     graph->filters[graph->filter_count - 1] = filter;
 365 }
 366
 367 /* search intelligently, once we insert in order */
 368 AVFilterContext *avfilter_graph_get_filter(AVFilterContext *ctx, char *name)
 369 {
 370     GraphContext *graph = ctx->priv;
 371     int i;
 372
 373     if(!name)
 374         return NULL;
 375
 376     for(i = 0; i < graph->filter_count; i ++)
 377         if(graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
 378             return graph->filters[i];
 379
 380     return NULL;
 381 }
 382
 383 static int query_formats(AVFilterContext *graphctx)
 384 {
 385     GraphContext *graph = graphctx->priv;
 386     AVFilterContext *linkfiltin  = graph->link_filter_in;
 387     AVFilterContext *linkfiltout = graph->link_filter_out;
 388     int i, j;
 389
 390     /* ask all the sub-filters for their supported colorspaces */
 391     for(i = 0; i < graph->filter_count; i ++) {
 392         if(graph->filters[i]->filter->query_formats)
 393             graph->filters[i]->filter->query_formats(graph->filters[i]);
 394         else
 395             avfilter_default_query_formats(graph->filters[i]);
 396     }
 397
 398     /* use these formats on our exported links */
 399     for(i = 0; i < linkfiltout->input_count; i ++) {
 400         avfilter_formats_ref( linkfiltout->inputs[i]->in_formats,
 401                              &linkfiltout->inputs[i]->out_formats);
 402
 403         if(graphctx->outputs[i])
 404             avfilter_formats_ref(linkfiltout->inputs[i]->in_formats,
 405                                  &graphctx->outputs[i]->in_formats);
 406     }
 407     for(i = 0; i < linkfiltin->output_count; i ++) {
 408         avfilter_formats_ref( linkfiltin->outputs[i]->out_formats,
 409                              &linkfiltin->outputs[i]->in_formats);
 410
 411         if(graphctx->inputs[i])
 412             avfilter_formats_ref(linkfiltin->outputs[i]->out_formats,
 413                                  &graphctx-> inputs[i]->out_formats);
 414     }
 415
 416     /* go through and merge as many format lists as possible */
 417     for(i = 0; i < graph->filter_count; i ++) {
 418         AVFilterContext *filter = graph->filters[i];
 419
 420         for(j = 0; j < filter->input_count; j ++) {
 421             AVFilterLink *link;
 422             if(!(link = filter->inputs[j]))
 423                 continue;
 424             if(link->in_formats != link->out_formats) {
 425                 if(!avfilter_merge_formats(link->in_formats,
 426                                            link->out_formats)) {
 427                     /* couldn't merge format lists. auto-insert scale filter */
 428                     AVFilterContext *scale;
 429
 430                     if(!(scale = avfilter_open(&avfilter_vf_scale, NULL)))
 431                         return -1;
 432                     if(scale->filter->init(scale, NULL, NULL) ||
 433                        avfilter_insert_filter(link, scale, 0, 0)) {
 434                         avfilter_destroy(scale);
 435                         return -1;
 436                     }
 437
 438                     avfilter_graph_add_filter(graphctx, scale);
 439                     scale->filter->query_formats(scale);
 440                     if(!avfilter_merge_formats(scale-> inputs[0]->in_formats,
 441                                               scale-> inputs[0]->out_formats) ||
 442                        !avfilter_merge_formats(scale->outputs[0]->in_formats,
 443                                               scale->outputs[0]->out_formats))
 444                         return -1;
 445                 }
 446             }
 447         }
 448     }
 449
 450     return 0;
 451 }
 452
 453 static void pick_format(AVFilterLink *link)
 454 {
 455     if(!link || !link->in_formats)
 456         return;
 457
 458     link->in_formats->format_count = 1;
 459     link->format = link->in_formats->formats[0];
 460
 461     avfilter_formats_unref(&link->in_formats);
 462     avfilter_formats_unref(&link->out_formats);
 463 }
 464
 465 static void pick_formats(GraphContext *graph)
 466 {
 467     int i, j;
 468
 469     for(i = 0; i < graph->filter_count; i ++) {
 470         AVFilterContext *filter = graph->filters[i];
 471
 472         if(filter->filter == &avfilter_vf_graph     ||
 473            filter->filter == &avfilter_vf_graphfile ||
 474            filter->filter == &avfilter_vf_graphdesc)
 475             pick_formats(filter->priv);
 476
 477         for(j = 0; j < filter->input_count; j ++)
 478             pick_format(filter->inputs[j]);
 479         for(j = 0; j < filter->output_count; j ++)
 480             pick_format(filter->outputs[j]);
 481     }
 482 }
 483
 484 int avfilter_graph_config_formats(AVFilterContext *graphctx)
 485 {
 486     GraphContext *graph = graphctx->priv;
 487
 488     /* find supported formats from sub-filters, and merge along links */
 489     if(query_formats(graphctx))
 490         return -1;
 491
 492     /* Once everything is merged, it's possible that we'll still have
 493      * multiple valid choices of colorspace. We pick the first one. */
 494     pick_formats(graph);
 495
 496     return 0;
 497 }
 498
 499 static int graph_load_from_desc(AVFilterContext *ctx, AVFilterGraphDesc *desc)
 500 {
 501     AVFilterGraphDescFilter *curfilt;
 502     AVFilterGraphDescLink   *curlink;
 503     AVFilterGraphDescExport *curpad;
 504     AVFilterContext *filt, *filtb;
 505
 506     AVFilter *filterdef;
 507
 508     /* create all filters */
 509     for(curfilt = desc->filters; curfilt; curfilt = curfilt->next) {
 510         if(!(filterdef = avfilter_get_by_name(curfilt->filter)) ||
 511            !(filt = avfilter_open(filterdef, curfilt->name))) {
 512             av_log(ctx, AV_LOG_ERROR,
 513                "error creating filter '%s'\n", curfilt->name);
 514             goto fail;
 515         }
 516         avfilter_graph_add_filter(ctx, filt);
 517         if(avfilter_init_filter(filt, curfilt->args, NULL)) {
 518             av_log(ctx, AV_LOG_ERROR,
 519                 "error initializing filter '%s'\n", curfilt->name);
 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