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
|
/*
* Copyright (c) 2003 Rich Felker
* Copyright (c) 2012 Stefano Sabatini
*
* 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
* field filter, based on libmpcodecs/vf_field.c by Rich Felker
*/
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "avfilter.h"
#include "internal.h"
enum FieldType { FIELD_TYPE_TOP = 0, FIELD_TYPE_BOTTOM };
typedef struct {
const AVClass *class;
enum FieldType type;
int nb_planes; ///< number of planes of the current format
} FieldContext;
#define OFFSET(x) offsetof(FieldContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption field_options[] = {
{"type", "set field type (top or bottom)", OFFSET(type), AV_OPT_TYPE_INT, {.i64=FIELD_TYPE_TOP}, 0, 1, FLAGS, "field_type" },
{"top", "select top field", 0, AV_OPT_TYPE_CONST, {.i64=FIELD_TYPE_TOP}, INT_MIN, INT_MAX, FLAGS, "field_type"},
{"bottom", "select bottom field", 0, AV_OPT_TYPE_CONST, {.i64=FIELD_TYPE_BOTTOM}, INT_MIN, INT_MAX, FLAGS, "field_type"},
{NULL}
};
AVFILTER_DEFINE_CLASS(field);
static int config_props_output(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
FieldContext *field = ctx->priv;
AVFilterLink *inlink = ctx->inputs[0];
field->nb_planes = av_pix_fmt_count_planes(outlink->format);
outlink->w = inlink->w;
outlink->h = (inlink->h + (field->type == FIELD_TYPE_TOP)) / 2;
av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d type:%s -> w:%d h:%d\n",
inlink->w, inlink->h, field->type == FIELD_TYPE_BOTTOM ? "bottom" : "top",
outlink->w, outlink->h);
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *inpicref)
{
FieldContext *field = inlink->dst->priv;
AVFilterLink *outlink = inlink->dst->outputs[0];
int i;
inpicref->height = outlink->h;
inpicref->interlaced_frame = 0;
for (i = 0; i < field->nb_planes; i++) {
if (field->type == FIELD_TYPE_BOTTOM)
inpicref->data[i] = inpicref->data[i] + inpicref->linesize[i];
inpicref->linesize[i] = 2 * inpicref->linesize[i];
}
return ff_filter_frame(outlink, inpicref);
}
static const AVFilterPad field_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad field_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_props_output,
},
{ NULL }
};
AVFilter avfilter_vf_field = {
.name = "field",
.description = NULL_IF_CONFIG_SMALL("Extract a field from the input video."),
.priv_size = sizeof(FieldContext),
.inputs = field_inputs,
.outputs = field_outputs,
.priv_class = &field_class,
};
|