Create a set of null callback functions.
[libav.git] / libavfilter / defaults.c
1 /*
2 * Filter layer - default implementations
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 /* TODO: buffer pool. see comment for avfilter_default_get_video_buffer() */
26 static void avfilter_default_free_video_buffer(AVFilterPic *pic)
27 {
28 av_free(pic->data[0]);
29 av_free(pic);
30 }
31
32 /* TODO: set the buffer's priv member to a context structure for the whole
33 * filter chain. This will allow for a buffer pool instead of the constant
34 * alloc & free cycle currently implemented. */
35 AVFilterPicRef *avfilter_default_get_video_buffer(AVFilterLink *link, int perms, int w, int h)
36 {
37 AVFilterPic *pic = av_mallocz(sizeof(AVFilterPic));
38 AVFilterPicRef *ref = av_mallocz(sizeof(AVFilterPicRef));
39 int i, tempsize;
40 char *buf;
41
42 ref->pic = pic;
43 ref->w = pic->w = w;
44 ref->h = pic->h = h;
45
46 /* make sure the buffer gets read permission or it's useless for output */
47 ref->perms = perms | AV_PERM_READ;
48
49 pic->refcount = 1;
50 pic->format = link->format;
51 pic->free = avfilter_default_free_video_buffer;
52 ff_fill_linesize((AVPicture *)pic, pic->format, ref->w);
53
54 for (i=0; i<4;i++)
55 pic->linesize[i] = FFALIGN(pic->linesize[i], 16);
56
57 tempsize = ff_fill_pointer((AVPicture *)pic, NULL, pic->format, ref->h);
58 buf = av_malloc(tempsize);
59 ff_fill_pointer((AVPicture *)pic, buf, pic->format, ref->h);
60
61 memcpy(ref->data, pic->data, sizeof(pic->data));
62 memcpy(ref->linesize, pic->linesize, sizeof(pic->linesize));
63
64 return ref;
65 }
66
67 void avfilter_default_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
68 {
69 AVFilterLink *out = NULL;
70
71 if(link->dst->output_count)
72 out = link->dst->outputs[0];
73
74 if(out) {
75 out->outpic = avfilter_get_video_buffer(out, AV_PERM_WRITE, out->w, out->h);
76 out->outpic->pts = picref->pts;
77 out->outpic->pos = picref->pos;
78 out->outpic->pixel_aspect = picref->pixel_aspect;
79 avfilter_start_frame(out, avfilter_ref_pic(out->outpic, ~0));
80 }
81 }
82
83 void avfilter_default_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
84 {
85 AVFilterLink *out = NULL;
86
87 if(link->dst->output_count)
88 out = link->dst->outputs[0];
89
90 if(out)
91 avfilter_draw_slice(out, y, h, slice_dir);
92 }
93
94 void avfilter_default_end_frame(AVFilterLink *link)
95 {
96 AVFilterLink *out = NULL;
97
98 if(link->dst->output_count)
99 out = link->dst->outputs[0];
100
101 avfilter_unref_pic(link->cur_pic);
102 link->cur_pic = NULL;
103
104 if(out) {
105 if(out->outpic) {
106 avfilter_unref_pic(out->outpic);
107 out->outpic = NULL;
108 }
109 avfilter_end_frame(out);
110 }
111 }
112
113 /**
114 * default config_link() implementation for output video links to simplify
115 * the implementation of one input one output video filters */
116 int avfilter_default_config_output_link(AVFilterLink *link)
117 {
118 if(link->src->input_count && link->src->inputs[0]) {
119 link->w = link->src->inputs[0]->w;
120 link->h = link->src->inputs[0]->h;
121 } else {
122 /* XXX: any non-simple filter which would cause this branch to be taken
123 * really should implement its own config_props() for this link. */
124 return -1;
125 }
126
127 return 0;
128 }
129
130 /**
131 * A helper for query_formats() which sets all links to the same list of
132 * formats. If there are no links hooked to this filter, the list of formats is
133 * freed.
134 *
135 * FIXME: this will need changed for filters with a mix of pad types
136 * (video + audio, etc)
137 */
138 void avfilter_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
139 {
140 int count = 0, i;
141
142 for(i = 0; i < ctx->input_count; i ++) {
143 if(ctx->inputs[i]) {
144 avfilter_formats_ref(formats, &ctx->inputs[i]->out_formats);
145 count ++;
146 }
147 }
148 for(i = 0; i < ctx->output_count; i ++) {
149 if(ctx->outputs[i]) {
150 avfilter_formats_ref(formats, &ctx->outputs[i]->in_formats);
151 count ++;
152 }
153 }
154
155 if(!count) {
156 av_free(formats->formats);
157 av_free(formats->refs);
158 av_free(formats);
159 }
160 }
161
162 int avfilter_default_query_formats(AVFilterContext *ctx)
163 {
164 avfilter_set_common_formats(ctx, avfilter_all_colorspaces());
165 return 0;
166 }
167
168 void avfilter_null_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
169 {
170 avfilter_start_frame(link->dst->outputs[0], picref);
171 }
172
173 void avfilter_null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
174 {
175 avfilter_draw_slice(link->dst->outputs[0], y, h, slice_dir);
176 }
177
178 void avfilter_null_end_frame(AVFilterLink *link)
179 {
180 avfilter_end_frame(link->dst->outputs[0]);
181 }
182
183 AVFilterPicRef *avfilter_null_get_video_buffer(AVFilterLink *link, int perms, int w, int h)
184 {
185 return avfilter_get_video_buffer(link->dst->outputs[0], perms, w, h);
186 }
187