1 /*
2 * Copyright (c) 2018 Marton Balint
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 "filters.h"
25 #include "internal.h"
26
27 typedef struct CueContext {
28 const AVClass *class;
29 int64_t first_pts;
30 int64_t cue;
31 int64_t preroll;
32 int64_t buffer;
33 int status;
34 } CueContext;
35
activate(AVFilterContext * ctx)36 static int activate(AVFilterContext *ctx)
37 {
38 AVFilterLink *inlink = ctx->inputs[0];
39 AVFilterLink *outlink = ctx->outputs[0];
40 CueContext *s = ctx->priv;
41
42 FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink);
43
44 if (ff_inlink_queued_frames(inlink)) {
45 AVFrame *frame = ff_inlink_peek_frame(inlink, 0);
46 int64_t pts = av_rescale_q(frame->pts, inlink->time_base, AV_TIME_BASE_Q);
47
48 if (!s->status) {
49 s->first_pts = pts;
50 s->status++;
51 }
52 if (s->status == 1) {
53 if (pts - s->first_pts < s->preroll) {
54 int ret = ff_inlink_consume_frame(inlink, &frame);
55 if (ret < 0)
56 return ret;
57 return ff_filter_frame(outlink, frame);
58 }
59 s->first_pts = pts;
60 s->status++;
61 }
62 if (s->status == 2) {
63 frame = ff_inlink_peek_frame(inlink, ff_inlink_queued_frames(inlink) - 1);
64 pts = av_rescale_q(frame->pts, inlink->time_base, AV_TIME_BASE_Q);
65 if (!(pts - s->first_pts < s->buffer && (av_gettime() - s->cue) < 0))
66 s->status++;
67 }
68 if (s->status == 3) {
69 int64_t diff;
70 while ((diff = (av_gettime() - s->cue)) < 0)
71 av_usleep(av_clip(-diff / 2, 100, 1000000));
72 s->status++;
73 }
74 if (s->status == 4) {
75 int ret = ff_inlink_consume_frame(inlink, &frame);
76 if (ret < 0)
77 return ret;
78 return ff_filter_frame(outlink, frame);
79 }
80 }
81
82 FF_FILTER_FORWARD_STATUS(inlink, outlink);
83 FF_FILTER_FORWARD_WANTED(outlink, inlink);
84
85 return FFERROR_NOT_READY;
86 }
87
88 #define OFFSET(x) offsetof(CueContext, x)
89 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
90 static const AVOption options[] = {
91 { "cue", "cue unix timestamp in microseconds", OFFSET(cue), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT64_MAX, FLAGS },
92 { "preroll", "preroll duration in seconds", OFFSET(preroll), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT64_MAX, FLAGS },
93 { "buffer", "buffer duration in seconds", OFFSET(buffer), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT64_MAX, FLAGS },
94 { NULL }
95 };
96
97 #if CONFIG_CUE_FILTER
98 #define cue_options options
99 AVFILTER_DEFINE_CLASS(cue);
100
101 static const AVFilterPad cue_inputs[] = {
102 {
103 .name = "default",
104 .type = AVMEDIA_TYPE_VIDEO,
105 },
106 { NULL }
107 };
108
109 static const AVFilterPad cue_outputs[] = {
110 {
111 .name = "default",
112 .type = AVMEDIA_TYPE_VIDEO,
113 },
114 { NULL }
115 };
116
117 AVFilter ff_vf_cue = {
118 .name = "cue",
119 .description = NULL_IF_CONFIG_SMALL("Delay filtering to match a cue."),
120 .priv_size = sizeof(CueContext),
121 .priv_class = &cue_class,
122 .inputs = cue_inputs,
123 .outputs = cue_outputs,
124 .activate = activate,
125 };
126 #endif /* CONFIG_CUE_FILTER */
127
128 #if CONFIG_ACUE_FILTER
129 #define acue_options options
130 AVFILTER_DEFINE_CLASS(acue);
131
132 static const AVFilterPad acue_inputs[] = {
133 {
134 .name = "default",
135 .type = AVMEDIA_TYPE_AUDIO,
136 },
137 { NULL }
138 };
139
140 static const AVFilterPad acue_outputs[] = {
141 {
142 .name = "default",
143 .type = AVMEDIA_TYPE_AUDIO,
144 },
145 { NULL }
146 };
147
148 AVFilter ff_af_acue = {
149 .name = "acue",
150 .description = NULL_IF_CONFIG_SMALL("Delay filtering to match a cue."),
151 .priv_size = sizeof(CueContext),
152 .priv_class = &acue_class,
153 .inputs = acue_inputs,
154 .outputs = acue_outputs,
155 .activate = activate,
156 };
157 #endif /* CONFIG_ACUE_FILTER */
158