Support passing parameters to filters.
[libav.git] / 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(pic->data));
59 memcpy(ref->linesize, pic->linesize, sizeof(pic->linesize));
60
61 return ref;
62 }
63
64 void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
65 {
66 link->cur_pic = picref;
67 }
68
69 void avfilter_default_end_frame(AVFilterLink *link)
70 {
71 avfilter_unref_pic(link->cur_pic);
72 link->cur_pic = NULL;
73 }
74
75 AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref)
76 {
77 AVFilterPicRef *ret = av_malloc(sizeof(AVFilterPicRef));
78 memcpy(ret, ref, sizeof(AVFilterPicRef));
79 ret->pic->refcount ++;
80 return ret;
81 }
82
83 void avfilter_unref_pic(AVFilterPicRef *ref)
84 {
85 if(-- ref->pic->refcount == 0)
86 ref->pic->free(ref->pic);
87 av_free(ref);
88 }
89
90 int avfilter_link(AVFilterContext *src, unsigned srcpad,
91 AVFilterContext *dst, unsigned dstpad)
92 {
93 AVFilterLink *link;
94
95 if(src->outputs[srcpad] || dst->inputs[dstpad])
96 return -1;
97
98 src->outputs[srcpad] =
99 dst->inputs[dstpad] = link = av_malloc(sizeof(AVFilterLink));
100
101 link->src = src;
102 link->dst = dst;
103 link->srcpad = srcpad;
104 link->dstpad = dstpad;
105 link->cur_pic = NULL;
106
107 src->filter->outputs[dstpad].set_video_props(link);
108 return 0;
109 }
110
111 AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms)
112 {
113 AVFilterPicRef *ret = NULL;
114
115 if(link->dst->filter->inputs[link->dstpad].get_video_buffer)
116 ret = link->dst->filter->inputs[link->dstpad].get_video_buffer(link, perms);
117
118 if(!ret)
119 ret = avfilter_default_get_video_buffer(link, perms);
120
121 return ret;
122 }
123
124 void avfilter_request_frame(AVFilterLink *link)
125 {
126 link->src->filter->outputs[link->srcpad].request_frame(link);
127 }
128
129 /* XXX: should we do the duplicating of the picture ref here, instead of
130 * forcing the source filter to do it? */
131 void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
132 {
133 void (*start_frame)(AVFilterLink *, AVFilterPicRef *);
134
135 start_frame = link->dst->filter->inputs[link->dstpad].start_frame;
136 if(!start_frame)
137 start_frame = avfilter_default_start_frame;
138
139 start_frame(link, picref);
140 }
141
142 void avfilter_end_frame(AVFilterLink *link)
143 {
144 void (*end_frame)(AVFilterLink *);
145
146 end_frame = link->dst->filter->inputs[link->dstpad].end_frame;
147 if(!end_frame)
148 end_frame = avfilter_default_end_frame;
149
150 end_frame(link);
151 }
152
153 void avfilter_draw_slice(AVFilterLink *link, uint8_t *data[4], int y, int h)
154 {
155 link->dst->filter->inputs[link->dstpad].draw_slice(link, data, y, h);
156 }
157
158 static int filter_cmp(const void *aa, const void *bb)
159 {
160 const AVFilter *a = *(const AVFilter **)aa, *b = *(const AVFilter **)bb;
161 return strcmp(a->name, b->name);
162 }
163
164 AVFilter *avfilter_get_by_name(char *name)
165 {
166 AVFilter key = { .name = name, };
167 AVFilter *key2 = &key;
168 AVFilter **ret;
169
170 ret = bsearch(&key2, filters, filter_count, sizeof(AVFilter **), filter_cmp);
171 if(ret)
172 return *ret;
173 return NULL;
174 }
175
176 /* FIXME: insert in order, rather than insert at end + resort */
177 void avfilter_register(AVFilter *filter)
178 {
179 filters = av_realloc(filters, sizeof(AVFilter*) * (filter_count+1));
180 filters[filter_count] = filter;
181 qsort(filters, ++filter_count, sizeof(AVFilter **), filter_cmp);
182 }
183
184 void avfilter_init(void)
185 {
186 avfilter_register(&vsrc_dummy);
187 avfilter_register(&vf_crop);
188 avfilter_register(&vf_passthrough);
189 avfilter_register(&vo_sdl);
190 }
191
192 void avfilter_uninit(void)
193 {
194 av_freep(&filters);
195 filter_count = 0;
196 }
197
198 static int pad_count(const AVFilterPad *pads)
199 {
200 AVFilterPad *p = (AVFilterPad *) pads;
201 int count;
202
203 for(count = 0; p->name; count ++) p ++;
204 return count;
205 }
206
207 static const char *filter_name(void *p)
208 {
209 AVFilterContext *filter = p;
210 return filter->filter->name;
211 }
212
213 AVFilterContext *avfilter_create(AVFilter *filter)
214 {
215 AVFilterContext *ret = av_malloc(sizeof(AVFilterContext));
216
217 ret->av_class = av_mallocz(sizeof(AVClass));
218 ret->av_class->item_name = filter_name;
219 ret->filter = filter;
220 ret->inputs = av_mallocz(sizeof(AVFilterLink*) * pad_count(filter->inputs));
221 ret->outputs = av_mallocz(sizeof(AVFilterLink*) * pad_count(filter->outputs));
222 ret->priv = av_mallocz(filter->priv_size);
223
224 return ret;
225 }
226
227 void avfilter_destroy(AVFilterContext *filter)
228 {
229 int i;
230
231 if(filter->filter->uninit)
232 filter->filter->uninit(filter);
233
234 for(i = 0; i < pad_count(filter->filter->inputs); i ++) {
235 if(filter->inputs[i])
236 filter->inputs[i]->src->outputs[filter->inputs[i]->srcpad] = NULL;
237 av_free(filter->inputs[i]);
238 }
239 for(i = 0; i < pad_count(filter->filter->outputs); i ++) {
240 if(filter->outputs[i])
241 filter->outputs[i]->dst->inputs[filter->outputs[i]->dstpad] = NULL;
242 av_free(filter->outputs[i]);
243 }
244
245 av_free(filter->inputs);
246 av_free(filter->outputs);
247 av_free(filter->priv);
248 av_free(filter->av_class);
249 av_free(filter);
250 }
251
252 AVFilterContext *avfilter_create_by_name(char *name)
253 {
254 AVFilter *filt;
255
256 if(!(filt = avfilter_get_by_name(name))) return NULL;
257 return avfilter_create(filt);
258 }
259
260 int avfilter_init_filter(AVFilterContext *filter, const char *args)
261 {
262 int ret, i;
263
264 if(filter->filter->init)
265 if((ret = filter->filter->init(filter, args))) return ret;
266 for(i = 0; i < pad_count(filter->filter->outputs); i ++)
267 if(filter->outputs[i])
268 filter->filter->outputs[i].set_video_props(filter->outputs[i]);
269 return 0;
270 }
271