FFmpeg
f_cue.c
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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 
37 {
38  AVFilterLink *inlink = ctx->inputs[0];
39  AVFilterLink *outlink = ctx->outputs[0];
40  CueContext *s = ctx->priv;
41 
43 
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) {
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) {
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) {
76  if (ret < 0)
77  return ret;
78  return ff_filter_frame(outlink, frame);
79  }
80  }
81 
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
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 
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
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 
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 */
ff_vf_cue
AVFilter ff_vf_cue
opt.h
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
FFERROR_NOT_READY
return FFERROR_NOT_READY
Definition: filter_design.txt:204
AV_TIME_BASE_Q
#define AV_TIME_BASE_Q
Internal time base represented as fractional value.
Definition: avutil.h:260
CueContext::cue
int64_t cue
Definition: f_cue.c:30
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
FLAGS
#define FLAGS
Definition: f_cue.c:89
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption
AVOption.
Definition: opt.h:246
AV_OPT_TYPE_DURATION
@ AV_OPT_TYPE_DURATION
Definition: opt.h:237
CueContext::buffer
int64_t buffer
Definition: f_cue.c:32
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:148
FF_FILTER_FORWARD_STATUS_BACK
#define FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink)
Forward the status on an output link to an input link.
Definition: filters.h:199
activate
static int activate(AVFilterContext *ctx)
Definition: f_cue.c:36
ff_inlink_consume_frame
int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe)
Take a frame from the link's FIFO and update the link's stats.
Definition: avfilter.c:1481
CueContext::first_pts
int64_t first_pts
Definition: f_cue.c:29
CueContext
Definition: f_cue.c:27
CueContext::preroll
int64_t preroll
Definition: f_cue.c:31
options
static const AVOption options[]
Definition: f_cue.c:90
pts
static int64_t pts
Definition: transcode_aac.c:647
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:54
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_OPT_TYPE_INT64
@ AV_OPT_TYPE_INT64
Definition: opt.h:224
outputs
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
filters.h
ctx
AVFormatContext * ctx
Definition: movenc.c:48
av_rescale_q
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
av_usleep
int av_usleep(unsigned usec)
Sleep for a period of time.
Definition: time.c:84
ff_inlink_peek_frame
AVFrame * ff_inlink_peek_frame(AVFilterLink *link, size_t idx)
Access a frame in the link fifo without consuming it.
Definition: avfilter.c:1520
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
NULL
#define NULL
Definition: coverity.c:32
time.h
inputs
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
Definition: filter_design.txt:243
ff_inlink_queued_frames
size_t ff_inlink_queued_frames(AVFilterLink *link)
Get the number of frames available on the link.
Definition: avfilter.c:1451
CueContext::status
int status
Definition: f_cue.c:33
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:188
FF_FILTER_FORWARD_WANTED
FF_FILTER_FORWARD_WANTED(outlink, inlink)
internal.h
AVFILTER_DEFINE_CLASS
#define AVFILTER_DEFINE_CLASS(fname)
Definition: internal.h:334
OFFSET
#define OFFSET(x)
Definition: f_cue.c:88
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:60
AVFilter
Filter definition.
Definition: avfilter.h:144
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
buffer
the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer
Definition: filter_design.txt:49
avfilter.h
AVFilterContext
An instance of a filter.
Definition: avfilter.h:338
av_gettime
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
diff
static av_always_inline int diff(const uint32_t a, const uint32_t b)
Definition: vf_palettegen.c:136
FF_FILTER_FORWARD_STATUS
FF_FILTER_FORWARD_STATUS(inlink, outlink)
ff_af_acue
AVFilter ff_af_acue