summaryrefslogtreecommitdiff
path: root/libavfilter/fifo.c
blob: 3fa4faab39f7882f08f2f19ef3969d0356298275 (plain)
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
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
/*
 * 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 filter
 */

#include "audio.h"
#include "avfilter.h"
#include "internal.h"
#include "video.h"

typedef struct Buf {
    AVFilterBufferRef *buf;
    struct Buf        *next;
} Buf;

typedef struct {
    Buf  root;
    Buf *last;   ///< last buffered frame
} 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;
    Buf *buf, *tmp;

    for (buf = fifo->root.next; buf; buf = tmp) {
        tmp = buf->next;
        avfilter_unref_buffer(buf->buf);
        av_free(buf);
    }
}

static void add_to_queue(AVFilterLink *inlink, AVFilterBufferRef *buf)
{
    FifoContext *fifo = inlink->dst->priv;

    fifo->last->next = av_mallocz(sizeof(Buf));
    fifo->last = fifo->last->next;
    fifo->last->buf = buf;
}

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;
    Buf *tmp;
    int ret;

    if (!fifo->root.next) {
        if ((ret = ff_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. */
    switch (outlink->type) {
    case AVMEDIA_TYPE_VIDEO:
        ff_start_frame(outlink, fifo->root.next->buf);
        ff_draw_slice (outlink, 0, outlink->h, 1);
        ff_end_frame  (outlink);
        break;
    case AVMEDIA_TYPE_AUDIO:
        ff_filter_samples(outlink, fifo->root.next->buf);
        break;
    default:
        return AVERROR(EINVAL);
    }

    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= ff_null_get_video_buffer,
                                    .start_frame     = add_to_queue,
                                    .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}},
};

AVFilter avfilter_af_afifo = {
    .name        = "afifo",
    .description = NULL_IF_CONFIG_SMALL("Buffer input frames and send them when they are requested."),

    .init      = init,
    .uninit    = uninit,

    .priv_size = sizeof(FifoContext),

    .inputs    = (AVFilterPad[]) {{ .name             = "default",
                                    .type             = AVMEDIA_TYPE_AUDIO,
                                    .get_audio_buffer = ff_null_get_audio_buffer,
                                    .filter_samples   = add_to_queue,
                                    .rej_perms        = AV_PERM_REUSE2, },
                                  { .name = NULL}},
    .outputs   = (AVFilterPad[]) {{ .name             = "default",
                                    .type             = AVMEDIA_TYPE_AUDIO,
                                    .request_frame    = request_frame, },
                                  { .name = NULL}},
};