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 <stdarg.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <stdio.h>
  26
  27 #include "avfilter.h"
  28 #include "allfilters.h"
  29
  30 /** list of registered filters, sorted by name */
  31 static int filter_count = 0;
  32 static AVFilter **filters = NULL;
  33
  34 /* TODO: buffer pool.  see comment for avfilter_default_get_video_buffer() */
  35 void avfilter_default_free_video_buffer(AVFilterPic *pic)
  36 {
  37     avpicture_free((AVPicture *) pic);
  38     av_free(pic);
  39 }
  40
  41 /* TODO: set the buffer's priv member to a context structure for the whole
  42  * filter chain.  This will allow for a buffer pool instead of the constant
  43  * alloc & free cycle currently implemented. */
  44 AVFilterPicRef *avfilter_default_get_video_buffer(AVFilterLink *link, int perms)
  45 {
  46     AVFilterPic *pic = av_mallocz(sizeof(AVFilterPic));
  47     AVFilterPicRef *ref = av_mallocz(sizeof(AVFilterPicRef));
  48
  49     ref->pic = pic;
  50     ref->w = link->w;
  51     ref->h = link->h;
  52     ref->perms = perms;
  53
  54     pic->refcount = 1;
  55     pic->format = link->format;
  56     pic->free = avfilter_default_free_video_buffer;
  57     avpicture_alloc((AVPicture *)pic, pic->format, ref->w, ref->h);
  58
  59     memcpy(ref->data,     pic->data,     sizeof(pic->data));
  60     memcpy(ref->linesize, pic->linesize, sizeof(pic->linesize));
  61
  62     return ref;
  63 }
  64
  65 void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
  66 {
  67     link->cur_pic = picref;
  68 }
  69
  70 void avfilter_default_end_frame(AVFilterLink *link)
  71 {
  72     avfilter_unref_pic(link->cur_pic);
  73     link->cur_pic = NULL;
  74 }
  75
  76 AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref)
  77 {
  78     AVFilterPicRef *ret = av_malloc(sizeof(AVFilterPicRef));
  79     memcpy(ret, ref, sizeof(AVFilterPicRef));
  80     ret->pic->refcount ++;
  81     return ret;
  82 }
  83
  84 void avfilter_unref_pic(AVFilterPicRef *ref)
  85 {
  86     if(-- ref->pic->refcount == 0)
  87         ref->pic->free(ref->pic);
  88     av_free(ref);
  89 }
  90
  91 int avfilter_link(AVFilterContext *src, unsigned srcpad,
  92                   AVFilterContext *dst, unsigned dstpad)
  93 {
  94     AVFilterLink *link;
  95     int *fmts[2], i, j;
  96
  97     if(src->outputs[srcpad] || dst->inputs[dstpad])
  98         return -1;
  99
 100     src->outputs[srcpad] =
 101     dst->inputs[dstpad]  = link = av_malloc(sizeof(AVFilterLink));
 102
 103     link->src = src;
 104     link->dst = dst;
 105     link->srcpad = srcpad;
 106     link->dstpad = dstpad;
 107     link->cur_pic = NULL;
 108
 109     /* find a format both filters support - TODO: auto-insert conversion filter */
 110     fmts[0] = src->filter->outputs[srcpad].query_formats(link);
 111     fmts[1] = dst->filter->inputs[dstpad].query_formats(link);
 112     for(i = 0; fmts[0][i] != -1; i ++)
 113         for(j = 0; fmts[1][j] != -1; j ++)
 114             if(fmts[0][i] == fmts[1][j]) {
 115                 link->format = fmts[0][i];
 116                 goto format_done;
 117             }
 118
 119 format_done:
 120     av_free(fmts[0]);
 121     av_free(fmts[1]);
 122     if(link->format == -1) {
 123         /* failed to find a format.  fail at creating the link */
 124         av_free(link);
 125         src->outputs[srcpad] = NULL;
 126         dst->inputs[dstpad]  = NULL;
 127         return -1;
 128     }
 129
 130     src->filter->outputs[srcpad].config_props(link);
 131     dst->filter->inputs[dstpad].config_props(link);
 132     return 0;
 133 }
 134
 135 AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms)
 136 {
 137     AVFilterPicRef *ret = NULL;
 138
 139     if(link->dst->filter->inputs[link->dstpad].get_video_buffer)
 140         ret = link->dst->filter->inputs[link->dstpad].get_video_buffer(link, perms);
 141
 142     if(!ret)
 143         ret = avfilter_default_get_video_buffer(link, perms);
 144
 145     return ret;
 146 }
 147
 148 void avfilter_request_frame(AVFilterLink *link)
 149 {
 150     link->src->filter->outputs[link->srcpad].request_frame(link);
 151 }
 152
 153 /* XXX: should we do the duplicating of the picture ref here, instead of
 154  * forcing the source filter to do it? */
 155 void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
 156 {
 157     void (*start_frame)(AVFilterLink *, AVFilterPicRef *);
 158
 159     start_frame = link->dst->filter->inputs[link->dstpad].start_frame;
 160     if(!start_frame)
 161         start_frame = avfilter_default_start_frame;
 162
 163     start_frame(link, picref);
 164 }
 165
 166 void avfilter_end_frame(AVFilterLink *link)
 167 {
 168     void (*end_frame)(AVFilterLink *);
 169
 170     end_frame = link->dst->filter->inputs[link->dstpad].end_frame;
 171     if(!end_frame)
 172         end_frame = avfilter_default_end_frame;
 173
 174     end_frame(link);
 175 }
 176
 177 void avfilter_draw_slice(AVFilterLink *link, uint8_t *data[4], int y, int h)
 178 {
 179     link->dst->filter->inputs[link->dstpad].draw_slice(link, data, y, h);
 180 }
 181
 182 static int filter_cmp(const void *aa, const void *bb)
 183 {
 184     const AVFilter *a = *(const AVFilter **)aa, *b = *(const AVFilter **)bb;
 185     return strcmp(a->name, b->name);
 186 }
 187
 188 AVFilter *avfilter_get_by_name(char *name)
 189 {
 190     AVFilter key = { .name = name, };
 191     AVFilter *key2 = &key;
 192     AVFilter **ret;
 193
 194     ret = bsearch(&key2, filters, filter_count, sizeof(AVFilter **), filter_cmp);
 195     if(ret)
 196         return *ret;
 197     return NULL;
 198 }
 199
 200 /* FIXME: insert in order, rather than insert at end + resort */
 201 void avfilter_register(AVFilter *filter)
 202 {
 203     filters = av_realloc(filters, sizeof(AVFilter*) * (filter_count+1));
 204     filters[filter_count] = filter;
 205     qsort(filters, ++filter_count, sizeof(AVFilter **), filter_cmp);
 206 }
 207
 208 void avfilter_init(void)
 209 {
 210     avfilter_register(&vsrc_dummy);
 211     avfilter_register(&vf_crop);
 212     avfilter_register(&vf_passthrough);
 213     avfilter_register(&vo_sdl);
 214 }
 215
 216 void avfilter_uninit(void)
 217 {
 218     av_freep(&filters);
 219     filter_count = 0;
 220 }
 221
 222 static int pad_count(const AVFilterPad *pads)
 223 {
 224     AVFilterPad *p = (AVFilterPad *) pads;
 225     int count;
 226
 227     for(count = 0; p->name; count ++) p ++;
 228     return count;
 229 }
 230
 231 static const char *filter_name(void *p)
 232 {
 233     AVFilterContext *filter = p;
 234     return filter->filter->name;
 235 }
 236
 237 AVFilterContext *avfilter_create(AVFilter *filter)
 238 {
 239     AVFilterContext *ret = av_malloc(sizeof(AVFilterContext));
 240
 241     ret->av_class = av_mallocz(sizeof(AVClass));
 242     ret->av_class->item_name = filter_name;
 243     ret->filter   = filter;
 244     ret->inputs   = av_mallocz(sizeof(AVFilterLink*) * pad_count(filter->inputs));
 245     ret->outputs  = av_mallocz(sizeof(AVFilterLink*) * pad_count(filter->outputs));
 246     ret->priv     = av_mallocz(filter->priv_size);
 247
 248     return ret;
 249 }
 250
 251 void avfilter_destroy(AVFilterContext *filter)
 252 {
 253     int i;
 254
 255     if(filter->filter->uninit)
 256         filter->filter->uninit(filter);
 257
 258     for(i = 0; i < pad_count(filter->filter->inputs); i ++) {
 259         if(filter->inputs[i])
 260             filter->inputs[i]->src->outputs[filter->inputs[i]->srcpad] = NULL;
 261         av_free(filter->inputs[i]);
 262     }
 263     for(i = 0; i < pad_count(filter->filter->outputs); i ++) {
 264         if(filter->outputs[i])
 265             filter->outputs[i]->dst->inputs[filter->outputs[i]->dstpad] = NULL;
 266         av_free(filter->outputs[i]);
 267     }
 268
 269     av_free(filter->inputs);
 270     av_free(filter->outputs);
 271     av_free(filter->priv);
 272     av_free(filter->av_class);
 273     av_free(filter);
 274 }
 275
 276 AVFilterContext *avfilter_create_by_name(char *name)
 277 {
 278     AVFilter *filt;
 279
 280     if(!(filt = avfilter_get_by_name(name))) return NULL;
 281     return avfilter_create(filt);
 282 }
 283
 284 int avfilter_init_filter(AVFilterContext *filter, const char *args)
 285 {
 286     int ret, i;
 287
 288     if(filter->filter->init)
 289         if((ret = filter->filter->init(filter, args))) return ret;
 290     return 0;
 291 }
 292
 293 int *avfilter_make_format_list(int len, ...)
 294 {
 295     int *ret, i;
 296     va_list vl;
 297
 298     ret = av_malloc(sizeof(int) * (len + 1));
 299     va_start(vl, len);
 300     for(i = 0; i < len; i ++)
 301         ret[i] = va_arg(vl, int);
 302     va_end(vl);
 303     ret[len] = -1;
 304
 305     return ret;
 306 }
 307