libavfilter/avfilter.c

   1 /*
   2  * filter layer
   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 "libavcodec/imgconvert.h"
  23 #include "avfilter.h"
  24
  25 unsigned avfilter_version(void) {
  26     return LIBAVFILTER_VERSION_INT;
  27 }
  28
  29 /** list of registered filters */
  30 static struct FilterList
  31 {
  32     AVFilter *filter;
  33     struct FilterList *next;
  34 } *filters = NULL;
  35
  36 /** helper macros to get the in/out pad on the dst/src filter */
  37 #define link_dpad(link)     link->dst-> input_pads[link->dstpad]
  38 #define link_spad(link)     link->src->output_pads[link->srcpad]
  39
  40 AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref, int pmask)
  41 {
  42     AVFilterPicRef *ret = av_malloc(sizeof(AVFilterPicRef));
  43     *ret = *ref;
  44     ret->perms &= pmask;
  45     ret->pic->refcount ++;
  46     return ret;
  47 }
  48
  49 void avfilter_unref_pic(AVFilterPicRef *ref)
  50 {
  51     if(!(--ref->pic->refcount))
  52         ref->pic->free(ref->pic);
  53     av_free(ref);
  54 }
  55
  56 void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
  57                          AVFilterPad **pads, AVFilterLink ***links,
  58                          AVFilterPad *newpad)
  59 {
  60     unsigned i;
  61
  62     idx = FFMIN(idx, *count);
  63
  64     *pads  = av_realloc(*pads,  sizeof(AVFilterPad)   * (*count + 1));
  65     *links = av_realloc(*links, sizeof(AVFilterLink*) * (*count + 1));
  66     memmove(*pads +idx+1, *pads +idx, sizeof(AVFilterPad)   * (*count-idx));
  67     memmove(*links+idx+1, *links+idx, sizeof(AVFilterLink*) * (*count-idx));
  68     memcpy(*pads+idx, newpad, sizeof(AVFilterPad));
  69     (*links)[idx] = NULL;
  70
  71     (*count) ++;
  72     for(i = idx+1; i < *count; i ++)
  73         if(*links[i])
  74             (*(unsigned *)((uint8_t *) *links[i] + padidx_off)) ++;
  75 }
  76
  77 int avfilter_link(AVFilterContext *src, unsigned srcpad,
  78                   AVFilterContext *dst, unsigned dstpad)
  79 {
  80     AVFilterLink *link;
  81
  82     if(src->output_count <= srcpad || dst->input_count <= dstpad ||
  83        src->outputs[srcpad]        || dst->inputs[dstpad])
  84         return -1;
  85
  86     src->outputs[srcpad] =
  87     dst-> inputs[dstpad] = link = av_mallocz(sizeof(AVFilterLink));
  88
  89     link->src     = src;
  90     link->dst     = dst;
  91     link->srcpad  = srcpad;
  92     link->dstpad  = dstpad;
  93     link->format  = PIX_FMT_NONE;
  94
  95     return 0;
  96 }
  97
  98 int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
  99                            unsigned in, unsigned out)
 100 {
 101     av_log(link->dst, AV_LOG_INFO, "auto-inserting filter '%s'\n",
 102             filt->filter->name);
 103
 104     link->dst->inputs[link->dstpad] = NULL;
 105     if(avfilter_link(filt, out, link->dst, link->dstpad)) {
 106         /* failed to link output filter to new filter */
 107         link->dst->inputs[link->dstpad] = link;
 108         return -1;
 109     }
 110
 111     /* re-hookup the link to the new destination filter we inserted */
 112     link->dst = filt;
 113     link->dstpad = in;
 114     filt->inputs[in] = link;
 115
 116     /* if any information on supported colorspaces already exists on the
 117      * link, we need to preserve that */
 118     if(link->out_formats)
 119         avfilter_formats_changeref(&link->out_formats,
 120                                    &filt->outputs[out]->out_formats);
 121
 122     return 0;
 123 }
 124
 125 int avfilter_config_links(AVFilterContext *filter)
 126 {
 127     int (*config_link)(AVFilterLink *);
 128     unsigned i;
 129
 130     for(i = 0; i < filter->input_count; i ++) {
 131         AVFilterLink *link = filter->inputs[i];
 132
 133         if(!link) continue;
 134
 135         switch(link->init_state) {
 136         case AVLINK_INIT:
 137             continue;
 138         case AVLINK_STARTINIT:
 139             av_log(filter, AV_LOG_INFO, "circular filter chain detected\n");
 140             return 0;
 141         case AVLINK_UNINIT:
 142             link->init_state = AVLINK_STARTINIT;
 143
 144             if(avfilter_config_links(link->src))
 145                 return -1;
 146
 147             if(!(config_link = link_spad(link).config_props))
 148                 config_link  = avfilter_default_config_output_link;
 149             if(config_link(link))
 150                 return -1;
 151
 152             if((config_link = link_dpad(link).config_props))
 153                 if(config_link(link))
 154                     return -1;
 155
 156             link->init_state = AVLINK_INIT;
 157         }
 158     }
 159
 160     return 0;
 161 }
 162
 163 AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms)
 164 {
 165     AVFilterPicRef *ret = NULL;
 166
 167     if(link_dpad(link).get_video_buffer)
 168         ret = link_dpad(link).get_video_buffer(link, perms);
 169
 170     if(!ret)
 171         ret = avfilter_default_get_video_buffer(link, perms);
 172
 173     return ret;
 174 }
 175
 176 int avfilter_request_frame(AVFilterLink *link)
 177 {
 178     if(link_spad(link).request_frame)
 179         return link_spad(link).request_frame(link);
 180     else if(link->src->inputs[0])
 181         return avfilter_request_frame(link->src->inputs[0]);
 182     else return -1;
 183 }
 184
 185 int avfilter_poll_frame(AVFilterLink *link)
 186 {
 187     int i, min=INT_MAX;
 188
 189     if(link_spad(link).poll_frame)
 190         return link_spad(link).poll_frame(link);
 191
 192     for (i=0; i<link->src->input_count; i++) {
 193         if(!link->src->inputs[i])
 194             return -1;
 195         min = FFMIN(min, avfilter_poll_frame(link->src->inputs[i]));
 196     }
 197
 198     return min;
 199 }
 200
 201 /* XXX: should we do the duplicating of the picture ref here, instead of
 202  * forcing the source filter to do it? */
 203 void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
 204 {
 205     void (*start_frame)(AVFilterLink *, AVFilterPicRef *);
 206     AVFilterPad *dst = &link_dpad(link);
 207
 208     if(!(start_frame = dst->start_frame))
 209         start_frame = avfilter_default_start_frame;
 210
 211     /* prepare to copy the picture if it has insufficient permissions */
 212     if((dst->min_perms & picref->perms) != dst->min_perms ||
 213         dst->rej_perms & picref->perms) {
 214         /*
 215         av_log(link->dst, AV_LOG_INFO,
 216                 "frame copy needed (have perms %x, need %x, reject %x)\n",
 217                 picref->perms,
 218                 link_dpad(link).min_perms, link_dpad(link).rej_perms);
 219         */
 220
 221         link->cur_pic = avfilter_default_get_video_buffer(link, dst->min_perms);
 222         link->srcpic = picref;
 223         link->cur_pic->pts = link->srcpic->pts;
 224         link->cur_pic->pixel_aspect = link->srcpic->pixel_aspect;
 225     }
 226     else
 227         link->cur_pic = picref;
 228
 229     start_frame(link, link->cur_pic);
 230 }
 231
 232 void avfilter_end_frame(AVFilterLink *link)
 233 {
 234     void (*end_frame)(AVFilterLink *);
 235
 236     if(!(end_frame = link_dpad(link).end_frame))
 237         end_frame = avfilter_default_end_frame;
 238
 239     end_frame(link);
 240
 241     /* unreference the source picture if we're feeding the destination filter
 242      * a copied version dues to permission issues */
 243     if(link->srcpic) {
 244         avfilter_unref_pic(link->srcpic);
 245         link->srcpic = NULL;
 246     }
 247
 248 }
 249
 250 void avfilter_draw_slice(AVFilterLink *link, int y, int h)
 251 {
 252     uint8_t *src[4], *dst[4];
 253     int i, j, hsub, vsub;
 254     void (*draw_slice)(AVFilterLink *, int, int);
 255
 256     /* copy the slice if needed for permission reasons */
 257     if(link->srcpic) {
 258         avcodec_get_chroma_sub_sample(link->format, &hsub, &vsub);
 259
 260         for(i = 0; i < 4; i ++) {
 261             if(link->srcpic->data[i]) {
 262                 src[i] = link->srcpic-> data[i] +
 263                     (y >> (i==0 ? 0 : vsub)) * link->srcpic-> linesize[i];
 264                 dst[i] = link->cur_pic->data[i] +
 265                     (y >> (i==0 ? 0 : vsub)) * link->cur_pic->linesize[i];
 266             } else
 267                 src[i] = dst[i] = NULL;
 268         }
 269
 270         for(i = 0; i < 4; i ++) {
 271             int planew =
 272                 ff_get_plane_bytewidth(link->format, link->cur_pic->w, i);
 273
 274             if(!src[i]) continue;
 275
 276             for(j = 0; j < h >> (i==0 ? 0 : vsub); j ++) {
 277                 memcpy(dst[i], src[i], planew);
 278                 src[i] += link->srcpic ->linesize[i];
 279                 dst[i] += link->cur_pic->linesize[i];
 280             }
 281         }
 282     }
 283
 284     if(!(draw_slice = link_dpad(link).draw_slice))
 285         draw_slice = avfilter_default_draw_slice;
 286     draw_slice(link, y, h);
 287 }
 288
 289 AVFilter *avfilter_get_by_name(const char *name)
 290 {
 291     struct FilterList *filt;
 292
 293     for(filt = filters; filt; filt = filt->next)
 294         if(!strcmp(filt->filter->name, name))
 295             return filt->filter;
 296
 297     return NULL;
 298 }
 299
 300 void avfilter_register(AVFilter *filter)
 301 {
 302     struct FilterList *newfilt = av_malloc(sizeof(struct FilterList));
 303
 304     newfilt->filter = filter;
 305     newfilt->next   = filters;
 306     filters         = newfilt;
 307 }
 308
 309 void avfilter_uninit(void)
 310 {
 311     struct FilterList *tmp;
 312
 313     for(; filters; filters = tmp) {
 314         tmp = filters->next;
 315         av_free(filters);
 316     }
 317 }
 318
 319 static int pad_count(const AVFilterPad *pads)
 320 {
 321     int count;
 322
 323     for(count = 0; pads->name; count ++) pads ++;
 324     return count;
 325 }
 326
 327 static const char *filter_name(void *p)
 328 {
 329     AVFilterContext *filter = p;
 330     return filter->filter->name;
 331 }
 332
 333 static const AVClass avfilter_class = {
 334     "AVFilter",
 335     filter_name
 336 };
 337
 338 AVFilterContext *avfilter_open(AVFilter *filter, const char *inst_name)
 339 {
 340     AVFilterContext *ret;
 341
 342     if (!filter)
 343         return 0;
 344
 345     ret = av_mallocz(sizeof(AVFilterContext));
 346
 347     ret->av_class = &avfilter_class;
 348     ret->filter   = filter;
 349     ret->name     = inst_name ? av_strdup(inst_name) : NULL;
 350     ret->priv     = av_mallocz(filter->priv_size);
 351
 352     ret->input_count  = pad_count(filter->inputs);
 353     if (ret->input_count) {
 354         ret->input_pads   = av_malloc(sizeof(AVFilterPad) * ret->input_count);
 355         memcpy(ret->input_pads, filter->inputs, sizeof(AVFilterPad) * ret->input_count);
 356         ret->inputs       = av_mallocz(sizeof(AVFilterLink*) * ret->input_count);
 357     }
 358
 359     ret->output_count = pad_count(filter->outputs);
 360     if (ret->output_count) {
 361         ret->output_pads  = av_malloc(sizeof(AVFilterPad) * ret->output_count);
 362         memcpy(ret->output_pads, filter->outputs, sizeof(AVFilterPad) * ret->output_count);
 363         ret->outputs      = av_mallocz(sizeof(AVFilterLink*) * ret->output_count);
 364     }
 365
 366     return ret;
 367 }
 368
 369 void avfilter_destroy(AVFilterContext *filter)
 370 {
 371     int i;
 372
 373     if(filter->filter->uninit)
 374         filter->filter->uninit(filter);
 375
 376     for(i = 0; i < filter->input_count; i ++) {
 377         if(filter->inputs[i])
 378             filter->inputs[i]->src->outputs[filter->inputs[i]->srcpad] = NULL;
 379         av_freep(&filter->inputs[i]);
 380     }
 381     for(i = 0; i < filter->output_count; i ++) {
 382         if(filter->outputs[i])
 383             filter->outputs[i]->dst->inputs[filter->outputs[i]->dstpad] = NULL;
 384         av_freep(&filter->outputs[i]);
 385     }
 386
 387     av_freep(&filter->name);
 388     av_freep(&filter->input_pads);
 389     av_freep(&filter->output_pads);
 390     av_freep(&filter->inputs);
 391     av_freep(&filter->outputs);
 392     av_freep(&filter->priv);
 393     av_free(filter);
 394 }
 395
 396 int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque)
 397 {
 398     int ret=0;
 399
 400     if(filter->filter->init)
 401         ret = filter->filter->init(filter, args, opaque);
 402     return ret;
 403 }
 404