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