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