summaryrefslogtreecommitdiffstats
path: root/libavfilter/vf_vflip.c
blob: c7c39d33416f822e37fe5fe4372a9bae54d3f860 (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
/*
 * Copyright (c) 2007 Bobby Bingham
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * video vertical flip filter
 */

#include "libavutil/internal.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "internal.h"
#include "video.h"

typedef struct FlipContext {
    const AVClass *class;
    int vsub;   ///< vertical chroma subsampling
} FlipContext;

static const AVOption vflip_options[] = {
    { NULL }
};

AVFILTER_DEFINE_CLASS(vflip);

static int config_input(AVFilterLink *link)
{
    FlipContext *flip = link->dst->priv;
    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);

    flip->vsub = desc->log2_chroma_h;

    return 0;
}

static AVFrame *get_video_buffer(AVFilterLink *link, int w, int h)
{
    FlipContext *flip = link->dst->priv;
    AVFrame *frame;
    int i;

    frame = ff_get_video_buffer(link->dst->outputs[0], w, h);
    if (!frame)
        return NULL;

    for (i = 0; i < 4; i ++) {
        int vsub = i == 1 || i == 2 ? flip->vsub : 0;
        int height = AV_CEIL_RSHIFT(h, vsub);

        if (frame->data[i]) {
            frame->data[i] += (height - 1) * frame->linesize[i];
            frame->linesize[i] = -frame->linesize[i];
        }
    }

    return frame;
}

static int filter_frame(AVFilterLink *link, AVFrame *frame)
{
    FlipContext *flip = link->dst->priv;
    int i;

    for (i = 0; i < 4; i ++) {
        int vsub = i == 1 || i == 2 ? flip->vsub : 0;
        int height = AV_CEIL_RSHIFT(link->h, vsub);

        if (frame->data[i]) {
            frame->data[i] += (height - 1) * frame->linesize[i];
            frame->linesize[i] = -frame->linesize[i];
        }
    }

    return ff_filter_frame(link->dst->outputs[0], frame);
}
static const AVFilterPad avfilter_vf_vflip_inputs[] = {
    {
        .name             = "default",
        .type             = AVMEDIA_TYPE_VIDEO,
        .get_video_buffer = get_video_buffer,
        .filter_frame     = filter_frame,
        .config_props     = config_input,
    },
    { NULL }
};

static const AVFilterPad avfilter_vf_vflip_outputs[] = {
    {
        .name = "default",
        .type = AVMEDIA_TYPE_VIDEO,
    },
    { NULL }
};

AVFilter ff_vf_vflip = {
    .name        = "vflip",
    .description = NULL_IF_CONFIG_SMALL("Flip the input video vertically."),
    .priv_size   = sizeof(FlipContext),
    .priv_class  = &vflip_class,
    .inputs      = avfilter_vf_vflip_inputs,
    .outputs     = avfilter_vf_vflip_outputs,
    .flags       = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};
OpenPOWER on IntegriCloud