path: root/libavfilter/vf_weave.c (plain)
blob: a5fc1b7403cc161eeb482e73bde3069502692e93

1	/*
2	* Copyright (c) 2013 Paul B Mahol
3	*
4	* This file is part of FFmpeg.
5	*
6	* FFmpeg is free software; you can redistribute it and/or
7	* modify it under the terms of the GNU Lesser General Public
8	* License as published by the Free Software Foundation; either
9	* version 2.1 of the License, or (at your option) any later version.
10	*
11	* FFmpeg is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14	* Lesser General Public License for more details.
15	*
16	* You should have received a copy of the GNU Lesser General Public
17	* License along with FFmpeg; if not, write to the Free Software
18	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19	*/
20
21	#include "libavutil/imgutils.h"
22	#include "libavutil/opt.h"
23	#include "libavutil/pixdesc.h"
24	#include "avfilter.h"
25	#include "internal.h"
26
27	typedef struct WeaveContext {
28	const AVClass *class;
29	int first_field;
30	int nb_planes;
31	int planeheight[4];
32	int linesize[4];
33
34	AVFrame *prev;
35	} WeaveContext;
36
37	#define OFFSET(x) offsetof(WeaveContext, x)
38	#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
39
40	static const AVOption weave_options[] = {
41	{ "first_field", "set first field", OFFSET(first_field), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS, "field"},
42	{ "top", "set top field first", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "field"},
43	{ "t", "set top field first", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "field"},
44	{ "bottom", "set bottom field first", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "field"},
45	{ "b", "set bottom field first", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "field"},
46	{ NULL }
47	};
48
49	AVFILTER_DEFINE_CLASS(weave);
50
51	static int config_props_output(AVFilterLink *outlink)
52	{
53	AVFilterContext *ctx = outlink->src;
54	WeaveContext *s = ctx->priv;
55	AVFilterLink *inlink = ctx->inputs[0];
56	const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
57	int ret;
58
59	outlink->time_base.num = inlink->time_base.num * 2;
60	outlink->time_base.den = inlink->time_base.den;
61	outlink->frame_rate.num = inlink->frame_rate.num;
62	outlink->frame_rate.den = inlink->frame_rate.den * 2;
63	outlink->w = inlink->w;
64	outlink->h = inlink->h * 2;
65
66	if ((ret = av_image_fill_linesizes(s->linesize, inlink->format, inlink->w)) < 0)
67	return ret;
68
69	s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
70	s->planeheight[0] = s->planeheight[3] = inlink->h;
71
72	s->nb_planes = av_pix_fmt_count_planes(inlink->format);
73
74	return 0;
75	}
76
77	static int filter_frame(AVFilterLink *inlink, AVFrame *in)
78	{
79	AVFilterContext *ctx = inlink->dst;
80	WeaveContext *s = ctx->priv;
81	AVFilterLink *outlink = ctx->outputs[0];
82	AVFrame *out;
83	int i;
84
85	if (!s->prev) {
86	s->prev = in;
87	return 0;
88	}
89
90	out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
91	if (!out) {
92	av_frame_free(&in);
93	av_frame_free(&s->prev);
94	return AVERROR(ENOMEM);
95	}
96	av_frame_copy_props(out, in);
97
98	for (i = 0; i < s->nb_planes; i++) {
99	av_image_copy_plane(out->data[i] + out->linesize[i] * s->first_field,
100	out->linesize[i] * 2,
101	in->data[i], in->linesize[i],
102	s->linesize[i], s->planeheight[i]);
103	av_image_copy_plane(out->data[i] + out->linesize[i] * !s->first_field,
104	out->linesize[i] * 2,
105	s->prev->data[i], s->prev->linesize[i],
106	s->linesize[i], s->planeheight[i]);
107	}
108
109	out->pts = in->pts / 2;
110	out->interlaced_frame = 1;
111	out->top_field_first = !s->first_field;
112
113	av_frame_free(&in);
114	av_frame_free(&s->prev);
115	return ff_filter_frame(outlink, out);
116	}
117
118	static av_cold void uninit(AVFilterContext *ctx)
119	{
120	WeaveContext *s = ctx->priv;
121
122	av_frame_free(&s->prev);
123	}
124
125	static const AVFilterPad weave_inputs[] = {
126	{
127	.name = "default",
128	.type = AVMEDIA_TYPE_VIDEO,
129	.filter_frame = filter_frame,
130	},
131	{ NULL }
132	};
133
134	static const AVFilterPad weave_outputs[] = {
135	{
136	.name = "default",
137	.type = AVMEDIA_TYPE_VIDEO,
138	.config_props = config_props_output,
139	},
140	{ NULL }
141	};
142
143	AVFilter ff_vf_weave = {
144	.name = "weave",
145	.description = NULL_IF_CONFIG_SMALL("Weave input video fields into frames."),
146	.priv_size = sizeof(WeaveContext),
147	.priv_class = &weave_class,
148	.uninit = uninit,
149	.inputs = weave_inputs,
150	.outputs = weave_outputs,
151	};
152