1 /*
2 * Copyright (c) 2015 Nicolas George
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 License
8 * 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
14 * GNU Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public License
17 * along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include "libavutil/opt.h"
22 #include "libavutil/time.h"
23 #include "avfilter.h"
24 #include "internal.h"
25 #include <float.h>
26
27 typedef struct RealtimeContext {
28 const AVClass *class;
29 int64_t delta;
30 int64_t limit;
31 double speed;
32 unsigned inited;
33 } RealtimeContext;
34
filter_frame(AVFilterLink * inlink,AVFrame * frame)35 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
36 {
37 AVFilterContext *ctx = inlink->dst;
38 RealtimeContext *s = ctx->priv;
39
40 if (frame->pts != AV_NOPTS_VALUE) {
41 int64_t pts = av_rescale_q(frame->pts, inlink->time_base, AV_TIME_BASE_Q) / s->speed;
42 int64_t now = av_gettime_relative();
43 int64_t sleep = pts - now + s->delta;
44 if (!s->inited) {
45 s->inited = 1;
46 sleep = 0;
47 s->delta = now - pts;
48 }
49 if (FFABS(sleep) > s->limit / s->speed) {
50 av_log(ctx, AV_LOG_WARNING,
51 "time discontinuity detected: %"PRIi64" us, resetting\n",
52 sleep);
53 sleep = 0;
54 s->delta = now - pts;
55 }
56 if (sleep > 0) {
57 av_log(ctx, AV_LOG_DEBUG, "sleeping %"PRIi64" us\n", sleep);
58 for (; sleep > 600000000; sleep -= 600000000)
59 av_usleep(600000000);
60 av_usleep(sleep);
61 }
62 }
63 return ff_filter_frame(inlink->dst->outputs[0], frame);
64 }
65
66 #define OFFSET(x) offsetof(RealtimeContext, x)
67 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
68 static const AVOption options[] = {
69 { "limit", "sleep time limit", OFFSET(limit), AV_OPT_TYPE_DURATION, { .i64 = 2000000 }, 0, INT64_MAX, FLAGS },
70 { "speed", "speed factor", OFFSET(speed), AV_OPT_TYPE_DOUBLE, { .dbl = 1.0 }, DBL_MIN, DBL_MAX, FLAGS },
71 { NULL }
72 };
73
74 #if CONFIG_REALTIME_FILTER
75 #define realtime_options options
76 AVFILTER_DEFINE_CLASS(realtime);
77
78 static const AVFilterPad avfilter_vf_realtime_inputs[] = {
79 {
80 .name = "default",
81 .type = AVMEDIA_TYPE_VIDEO,
82 .filter_frame = filter_frame,
83 },
84 { NULL }
85 };
86
87 static const AVFilterPad avfilter_vf_realtime_outputs[] = {
88 {
89 .name = "default",
90 .type = AVMEDIA_TYPE_VIDEO,
91 },
92 { NULL }
93 };
94
95 AVFilter ff_vf_realtime = {
96 .name = "realtime",
97 .description = NULL_IF_CONFIG_SMALL("Slow down filtering to match realtime."),
98 .priv_size = sizeof(RealtimeContext),
99 .priv_class = &realtime_class,
100 .inputs = avfilter_vf_realtime_inputs,
101 .outputs = avfilter_vf_realtime_outputs,
102 };
103 #endif /* CONFIG_REALTIME_FILTER */
104
105 #if CONFIG_AREALTIME_FILTER
106
107 #define arealtime_options options
108 AVFILTER_DEFINE_CLASS(arealtime);
109
110 static const AVFilterPad arealtime_inputs[] = {
111 {
112 .name = "default",
113 .type = AVMEDIA_TYPE_AUDIO,
114 .filter_frame = filter_frame,
115 },
116 { NULL }
117 };
118
119 static const AVFilterPad arealtime_outputs[] = {
120 {
121 .name = "default",
122 .type = AVMEDIA_TYPE_AUDIO,
123 },
124 { NULL }
125 };
126
127 AVFilter ff_af_arealtime = {
128 .name = "arealtime",
129 .description = NULL_IF_CONFIG_SMALL("Slow down filtering to match realtime."),
130 .priv_size = sizeof(RealtimeContext),
131 .priv_class = &arealtime_class,
132 .inputs = arealtime_inputs,
133 .outputs = arealtime_outputs,
134 };
135 #endif /* CONFIG_AREALTIME_FILTER */
136