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/pixdesc.h"
22 #include "avfilter.h"
23 #include "filters.h"
24 #include "internal.h"
25
26 typedef struct SeparateFieldsContext {
27 int nb_planes;
28 AVFrame *second;
29 } SeparateFieldsContext;
30
config_props_output(AVFilterLink * outlink)31 static int config_props_output(AVFilterLink *outlink)
32 {
33 AVFilterContext *ctx = outlink->src;
34 SeparateFieldsContext *s = ctx->priv;
35 AVFilterLink *inlink = ctx->inputs[0];
36
37 s->nb_planes = av_pix_fmt_count_planes(inlink->format);
38
39 if (inlink->h & 1) {
40 av_log(ctx, AV_LOG_ERROR, "height must be even\n");
41 return AVERROR_INVALIDDATA;
42 }
43
44 outlink->time_base.num = inlink->time_base.num;
45 outlink->time_base.den = inlink->time_base.den * 2;
46 outlink->frame_rate.num = inlink->frame_rate.num * 2;
47 outlink->frame_rate.den = inlink->frame_rate.den;
48 outlink->w = inlink->w;
49 outlink->h = inlink->h / 2;
50
51 return 0;
52 }
53
extract_field(AVFrame * frame,int nb_planes,int type)54 static void extract_field(AVFrame *frame, int nb_planes, int type)
55 {
56 int i;
57
58 for (i = 0; i < nb_planes; i++) {
59 if (type)
60 frame->data[i] = frame->data[i] + frame->linesize[i];
61 frame->linesize[i] *= 2;
62 }
63 }
64
filter_frame(AVFilterLink * inlink,AVFrame * inpicref)65 static int filter_frame(AVFilterLink *inlink, AVFrame *inpicref)
66 {
67 AVFilterContext *ctx = inlink->dst;
68 SeparateFieldsContext *s = ctx->priv;
69 AVFilterLink *outlink = ctx->outputs[0];
70 int ret;
71
72 inpicref->height = outlink->h;
73 inpicref->interlaced_frame = 0;
74
75 if (!s->second) {
76 goto clone;
77 } else {
78 AVFrame *second = s->second;
79
80 extract_field(second, s->nb_planes, second->top_field_first);
81
82 if (second->pts != AV_NOPTS_VALUE &&
83 inpicref->pts != AV_NOPTS_VALUE)
84 second->pts += inpicref->pts;
85 else
86 second->pts = AV_NOPTS_VALUE;
87
88 ret = ff_filter_frame(outlink, second);
89 if (ret < 0)
90 return ret;
91 clone:
92 s->second = av_frame_clone(inpicref);
93 if (!s->second)
94 return AVERROR(ENOMEM);
95 }
96
97 extract_field(inpicref, s->nb_planes, !inpicref->top_field_first);
98
99 if (inpicref->pts != AV_NOPTS_VALUE)
100 inpicref->pts *= 2;
101
102 return ff_filter_frame(outlink, inpicref);
103 }
104
flush_frame(AVFilterLink * outlink,int64_t pts,int64_t * out_pts)105 static int flush_frame(AVFilterLink *outlink, int64_t pts, int64_t *out_pts)
106 {
107 AVFilterContext *ctx = outlink->src;
108 SeparateFieldsContext *s = ctx->priv;
109 int ret = 0;
110
111 if (s->second) {
112 *out_pts = s->second->pts += pts;
113 extract_field(s->second, s->nb_planes, s->second->top_field_first);
114 ret = ff_filter_frame(outlink, s->second);
115 s->second = NULL;
116 }
117
118 return ret;
119 }
120
activate(AVFilterContext * ctx)121 static int activate(AVFilterContext *ctx)
122 {
123 AVFilterLink *inlink = ctx->inputs[0];
124 AVFilterLink *outlink = ctx->outputs[0];
125 AVFrame *in;
126 int64_t pts;
127 int ret, status;
128
129 FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink);
130
131 ret = ff_inlink_consume_frame(inlink, &in);
132 if (ret < 0)
133 return ret;
134 if (ret > 0)
135 return filter_frame(inlink, in);
136
137 if (ff_inlink_acknowledge_status(inlink, &status, &pts)) {
138 if (status == AVERROR_EOF) {
139 int64_t out_pts = pts;
140
141 ret = flush_frame(outlink, pts, &out_pts);
142 ff_outlink_set_status(outlink, status, out_pts);
143 return ret;
144 }
145 }
146
147 FF_FILTER_FORWARD_WANTED(outlink, inlink);
148
149 return FFERROR_NOT_READY;
150 }
151
uninit(AVFilterContext * ctx)152 static av_cold void uninit(AVFilterContext *ctx)
153 {
154 SeparateFieldsContext *s = ctx->priv;
155
156 av_frame_free(&s->second);
157 }
158
159 static const AVFilterPad separatefields_inputs[] = {
160 {
161 .name = "default",
162 .type = AVMEDIA_TYPE_VIDEO,
163 },
164 { NULL }
165 };
166
167 static const AVFilterPad separatefields_outputs[] = {
168 {
169 .name = "default",
170 .type = AVMEDIA_TYPE_VIDEO,
171 .config_props = config_props_output,
172 },
173 { NULL }
174 };
175
176 AVFilter ff_vf_separatefields = {
177 .name = "separatefields",
178 .description = NULL_IF_CONFIG_SMALL("Split input video frames into fields."),
179 .priv_size = sizeof(SeparateFieldsContext),
180 .activate = activate,
181 .uninit = uninit,
182 .inputs = separatefields_inputs,
183 .outputs = separatefields_outputs,
184 };
185