1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
/*
* Copyright (c) 2007 Bobby Bingham
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* FIFO buffering video filter
*/
#include "avfilter.h"
typedef struct BufPic {
AVFilterBufferRef *picref;
struct BufPic *next;
} BufPic;
typedef struct {
BufPic root;
BufPic *last; ///< last buffered picture
} FifoContext;
static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
{
FifoContext *fifo = ctx->priv;
fifo->last = &fifo->root;
av_log(ctx, AV_LOG_INFO, "\n");
return 0;
}
static av_cold void uninit(AVFilterContext *ctx)
{
FifoContext *fifo = ctx->priv;
BufPic *pic, *tmp;
for (pic = fifo->root.next; pic; pic = tmp) {
tmp = pic->next;
avfilter_unref_buffer(pic->picref);
av_free(pic);
}
}
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
{
FifoContext *fifo = inlink->dst->priv;
fifo->last->next = av_mallocz(sizeof(BufPic));
fifo->last = fifo->last->next;
fifo->last->picref = picref;
}
static void end_frame(AVFilterLink *inlink) { }
static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir) { }
static int request_frame(AVFilterLink *outlink)
{
FifoContext *fifo = outlink->src->priv;
BufPic *tmp;
int ret;
if (!fifo->root.next) {
if ((ret = avfilter_request_frame(outlink->src->inputs[0]) < 0))
return ret;
}
/* by doing this, we give ownership of the reference to the next filter,
* so we don't have to worry about dereferencing it ourselves. */
avfilter_start_frame(outlink, fifo->root.next->picref);
avfilter_draw_slice (outlink, 0, outlink->h, 1);
avfilter_end_frame (outlink);
if (fifo->last == fifo->root.next)
fifo->last = &fifo->root;
tmp = fifo->root.next->next;
av_free(fifo->root.next);
fifo->root.next = tmp;
return 0;
}
AVFilter avfilter_vf_fifo = {
.name = "fifo",
.description = NULL_IF_CONFIG_SMALL("Buffer input images and send them when they are requested."),
.init = init,
.uninit = uninit,
.priv_size = sizeof(FifoContext),
.inputs = (AVFilterPad[]) {{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.get_video_buffer= avfilter_null_get_video_buffer,
.start_frame = start_frame,
.draw_slice = draw_slice,
.end_frame = end_frame,
.rej_perms = AV_PERM_REUSE2, },
{ .name = NULL}},
.outputs = (AVFilterPad[]) {{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.request_frame = request_frame, },
{ .name = NULL}},
};
|
