aboutsummaryrefslogtreecommitdiffstats
path: root/libavfilter/vf_fieldorder.c
blob: eb5e1890416f7108dd4da75d90990ed841d9c786 (plain) (blame)
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
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
/*
 * Copyright (c) 2011 Mark Himsley
 *
 * 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 field order filter, heavily influenced by vf_pad.c
 */

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

typedef struct {
    const AVClass *class;
    int dst_tff;               ///< output bff/tff
    int          line_size[4]; ///< bytes of pixel data per line for each plane
} FieldOrderContext;

static int query_formats(AVFilterContext *ctx)
{
    AVFilterFormats  *formats;
    enum AVPixelFormat pix_fmt;
    int              ret;

    /** accept any input pixel format that is not hardware accelerated, not
     *  a bitstream format, and does not have vertically sub-sampled chroma */
    if (ctx->inputs[0]) {
        formats = NULL;
        for (pix_fmt = 0; pix_fmt < AV_PIX_FMT_NB; pix_fmt++) {
            const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
            if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL ||
                  desc->flags & AV_PIX_FMT_FLAG_PAL     ||
                  desc->flags & AV_PIX_FMT_FLAG_BITSTREAM) &&
                desc->nb_components && !desc->log2_chroma_h &&
                (ret = ff_add_format(&formats, pix_fmt)) < 0) {
                ff_formats_unref(&formats);
                return ret;
            }
        }
        ff_formats_ref(formats, &ctx->inputs[0]->out_formats);
        ff_formats_ref(formats, &ctx->outputs[0]->in_formats);
    }

    return 0;
}

static int config_input(AVFilterLink *inlink)
{
    AVFilterContext   *ctx = inlink->dst;
    FieldOrderContext *s   = ctx->priv;

    return av_image_fill_linesizes(s->line_size, inlink->format, inlink->w);
}

static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
{
    AVFilterContext   *ctx     = inlink->dst;
    FieldOrderContext *s       = ctx->priv;
    AVFilterLink      *outlink = ctx->outputs[0];
    int h, plane, src_line_step, dst_line_step, line_size, line;
    uint8_t *dst, *src;
    AVFrame *out;

    if (!frame->interlaced_frame ||
        frame->top_field_first == s->dst_tff) {
        av_log(ctx, AV_LOG_VERBOSE,
               "Skipping %s.\n",
               frame->interlaced_frame ?
               "frame with same field order" : "progressive frame");
        return ff_filter_frame(outlink, frame);
    }

    if (av_frame_is_writable(frame)) {
        out = frame;
    } else {
        out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
        if (!out) {
            av_frame_free(&frame);
            return AVERROR(ENOMEM);
        }
        av_frame_copy_props(out, frame);
    }

    av_dlog(ctx,
            "picture will move %s one line\n",
            s->dst_tff ? "up" : "down");
    h = frame->height;
    for (plane = 0; plane < 4 && frame->data[plane] && frame->linesize[plane]; plane++) {
        dst_line_step = out->linesize[plane];
        src_line_step = frame->linesize[plane];
        line_size = s->line_size[plane];
        dst = out->data[plane];
        src = frame->data[plane];
        if (s->dst_tff) {
            /** Move every line up one line, working from
             *  the top to the bottom of the frame.
             *  The original top line is lost.
             *  The new last line is created as a copy of the
             *  penultimate line from that field. */
            for (line = 0; line < h; line++) {
                if (1 + line < frame->height) {
                    memcpy(dst, src + src_line_step, line_size);
                } else {
                    memcpy(dst, src - 2 * src_line_step, line_size);
                }
                dst += dst_line_step;
                src += src_line_step;
            }
        } else {
            /** Move every line down one line, working from
             *  the bottom to the top of the frame.
             *  The original bottom line is lost.
             *  The new first line is created as a copy of the
             *  second line from that field. */
            dst += (h - 1) * dst_line_step;
            src += (h - 1) * src_line_step;
            for (line = h - 1; line >= 0 ; line--) {
                if (line > 0) {
                    memcpy(dst, src - src_line_step, line_size);
                } else {
                    memcpy(dst, src + 2 * src_line_step, line_size);
                }
                dst -= dst_line_step;
                src -= src_line_step;
            }
        }
    }
    out->top_field_first = s->dst_tff;

    if (frame != out)
        av_frame_free(&frame);
    return ff_filter_frame(outlink, out);
}

#define OFFSET(x) offsetof(FieldOrderContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM

static const AVOption fieldorder_options[] = {
    { "order", "output field order", OFFSET(dst_tff), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, FLAGS, "order" },
        { "bff", "bottom field first", 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, .flags=FLAGS, .unit = "order" },
        { "tff", "top field first",    0, AV_OPT_TYPE_CONST, { .i64 = 1 }, .flags=FLAGS, .unit = "order" },
    { NULL }
};

AVFILTER_DEFINE_CLASS(fieldorder);

static const AVFilterPad avfilter_vf_fieldorder_inputs[] = {
    {
        .name         = "default",
        .type         = AVMEDIA_TYPE_VIDEO,
        .config_props = config_input,
        .filter_frame = filter_frame,
    },
    { NULL }
};

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

AVFilter avfilter_vf_fieldorder = {
    .name          = "fieldorder",
    .description   = NULL_IF_CONFIG_SMALL("Set the field order."),
    .priv_size     = sizeof(FieldOrderContext),
    .priv_class    = &fieldorder_class,
    .query_formats = query_formats,
    .inputs        = avfilter_vf_fieldorder_inputs,
    .outputs       = avfilter_vf_fieldorder_outputs,
    .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};