FFmpeg
f_loop.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2016 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 "config_components.h"
22 
23 #include "libavutil/audio_fifo.h"
24 #include "libavutil/internal.h"
25 #include "libavutil/mem.h"
26 #include "libavutil/opt.h"
27 #include "avfilter.h"
28 #include "audio.h"
29 #include "filters.h"
30 #include "internal.h"
31 #include "video.h"
32 
33 typedef struct LoopContext {
34  const AVClass *class;
35 
39  int nb_frames;
41  int64_t time_pts;
42  int64_t duration;
43  int64_t current_sample;
44  int64_t nb_samples;
45  int64_t ignored_samples;
46 
47  int loop;
48  int eof;
49  int64_t size;
50  int64_t start;
51  int64_t time;
52  int64_t pts;
53  int64_t pts_offset;
54  int64_t eof_pts;
55 } LoopContext;
56 
57 #define AFLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
58 #define VFLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
59 #define OFFSET(x) offsetof(LoopContext, x)
60 
62 {
63  LoopContext *s = ctx->priv;
64 
65  if (!s->size)
66  av_log(ctx, AV_LOG_WARNING, "Number of %s to loop is not set!\n",
67  ctx->input_pads[0].type == AVMEDIA_TYPE_VIDEO ? "frames" : "samples");
68 }
69 
71 {
72  LoopContext *s = ctx->priv;
73 
74  if (s->time != INT64_MAX) {
75  int64_t time_pts = av_rescale_q(s->time, AV_TIME_BASE_Q, tb);
76  if (s->time_pts == AV_NOPTS_VALUE || time_pts < s->time_pts)
77  s->time_pts = time_pts;
78  }
79 }
80 
81 #if CONFIG_ALOOP_FILTER
82 
83 static int aconfig_input(AVFilterLink *inlink)
84 {
85  AVFilterContext *ctx = inlink->dst;
86  LoopContext *s = ctx->priv;
87 
88  s->time_pts = AV_NOPTS_VALUE;
89 
90  s->fifo = av_audio_fifo_alloc(inlink->format, inlink->ch_layout.nb_channels, 8192);
91  s->left = av_audio_fifo_alloc(inlink->format, inlink->ch_layout.nb_channels, 8192);
92  if (!s->fifo || !s->left)
93  return AVERROR(ENOMEM);
94 
95  check_size(ctx);
96 
97  return 0;
98 }
99 
100 static av_cold void auninit(AVFilterContext *ctx)
101 {
102  LoopContext *s = ctx->priv;
103 
104  av_audio_fifo_free(s->fifo);
105  av_audio_fifo_free(s->left);
106 }
107 
108 static int push_samples(AVFilterContext *ctx, int nb_samples)
109 {
110  AVFilterLink *outlink = ctx->outputs[0];
111  LoopContext *s = ctx->priv;
112  AVFrame *out;
113  int ret = 0, i = 0;
114 
115  while (s->loop != 0 && i < nb_samples) {
116  out = ff_get_audio_buffer(outlink, FFMIN(nb_samples, s->nb_samples - s->current_sample));
117  if (!out)
118  return AVERROR(ENOMEM);
119  ret = av_audio_fifo_peek_at(s->fifo, (void **)out->extended_data, out->nb_samples, s->current_sample);
120  if (ret < 0) {
121  av_frame_free(&out);
122  return ret;
123  }
124  out->pts = s->pts;
125  out->nb_samples = ret;
126  s->pts += av_rescale_q(out->nb_samples, (AVRational){1, outlink->sample_rate}, outlink->time_base);
127  i += out->nb_samples;
128  s->current_sample += out->nb_samples;
129 
130  ret = ff_filter_frame(outlink, out);
131  if (ret < 0)
132  return ret;
133 
134  if (s->current_sample >= s->nb_samples) {
135  s->current_sample = 0;
136 
137  if (s->loop > 0)
138  s->loop--;
139  }
140  }
141 
142  return ret;
143 }
144 
145 static int afilter_frame(AVFilterLink *inlink, AVFrame *frame)
146 {
147  AVFilterContext *ctx = inlink->dst;
148  AVFilterLink *outlink = ctx->outputs[0];
149  LoopContext *s = ctx->priv;
150  int ret = 0;
151 
152  if (((s->start >= 0 && s->ignored_samples + frame->nb_samples > s->start) ||
153  (s->time_pts != AV_NOPTS_VALUE &&
154  frame->pts >= s->time_pts)) &&
155  s->size > 0 && s->loop != 0) {
156  if (s->nb_samples < s->size) {
157  int written = FFMIN(frame->nb_samples, s->size - s->nb_samples);
158  int drain = 0;
159 
160  if (s->start < 0)
161  s->start = inlink->sample_count_out - written;
162 
163  ret = av_audio_fifo_write(s->fifo, (void **)frame->extended_data, written);
164  if (ret < 0)
165  return ret;
166  if (!s->nb_samples) {
167  drain = FFMAX(0, s->start - s->ignored_samples);
168  s->pts = frame->pts;
169  av_audio_fifo_drain(s->fifo, drain);
170  s->pts += av_rescale_q(s->start - s->ignored_samples, (AVRational){1, outlink->sample_rate}, outlink->time_base);
171  }
172  s->nb_samples += ret - drain;
173  drain = frame->nb_samples - written;
174  if (s->nb_samples == s->size && drain > 0) {
175  int ret2;
176 
177  ret2 = av_audio_fifo_write(s->left, (void **)frame->extended_data, frame->nb_samples);
178  if (ret2 < 0)
179  return ret2;
180  av_audio_fifo_drain(s->left, drain);
181  }
182  frame->nb_samples = ret;
183  s->pts += av_rescale_q(ret, (AVRational){1, outlink->sample_rate}, outlink->time_base);
184  ret = ff_filter_frame(outlink, frame);
185  } else {
186  int nb_samples = frame->nb_samples;
187 
189  ret = push_samples(ctx, nb_samples);
190  }
191  } else {
192  s->ignored_samples += frame->nb_samples;
193  frame->pts = s->pts;
194  s->pts += av_rescale_q(frame->nb_samples, (AVRational){1, outlink->sample_rate}, outlink->time_base);
195  ret = ff_filter_frame(outlink, frame);
196  }
197 
198  return ret;
199 }
200 
201 static int arequest_frame(AVFilterLink *outlink)
202 {
203  AVFilterContext *ctx = outlink->src;
204  LoopContext *s = ctx->priv;
205  int ret = 0;
206 
207  if ((!s->size) ||
208  (s->nb_samples < s->size) ||
209  (s->nb_samples >= s->size && s->loop == 0)) {
210  int nb_samples = av_audio_fifo_size(s->left);
211 
212  if (s->loop == 0 && nb_samples > 0) {
213  AVFrame *out;
214 
215  out = ff_get_audio_buffer(outlink, nb_samples);
216  if (!out)
217  return AVERROR(ENOMEM);
218  av_audio_fifo_read(s->left, (void **)out->extended_data, nb_samples);
219  out->pts = s->pts;
220  s->pts += av_rescale_q(nb_samples, (AVRational){1, outlink->sample_rate}, outlink->time_base);
221  ret = ff_filter_frame(outlink, out);
222  if (ret < 0)
223  return ret;
224  }
225  ret = ff_request_frame(ctx->inputs[0]);
226  } else {
227  ret = push_samples(ctx, 1024);
228  }
229 
230  if (s->eof && s->nb_samples > 0 && s->loop != 0) {
231  ret = push_samples(ctx, 1024);
232  }
233 
234  return ret;
235 }
236 
237 static int aactivate(AVFilterContext *ctx)
238 {
239  AVFilterLink *inlink = ctx->inputs[0];
240  AVFilterLink *outlink = ctx->outputs[0];
241  LoopContext *s = ctx->priv;
242  AVFrame *frame = NULL;
243  int ret, status;
244 
246 
247  update_time(ctx, inlink->time_base);
248 
249  if (!s->eof && (s->nb_samples < s->size || !s->loop || !s->size)) {
250  const int in_nb_samples = FFMIN(1024, s->size - s->nb_samples);
251  if (in_nb_samples == 0)
253  else
254  ret = ff_inlink_consume_samples(inlink, in_nb_samples, in_nb_samples, &frame);
255  if (ret < 0)
256  return ret;
257  if (ret > 0)
258  return afilter_frame(inlink, frame);
259  }
260 
261  if (!s->eof && ff_inlink_acknowledge_status(inlink, &status, &s->eof_pts)) {
262  if (status == AVERROR_EOF) {
263  s->size = s->nb_samples;
264  s->eof = 1;
265  }
266  }
267 
268  if (s->eof && (!s->loop || !s->size)) {
269  ff_outlink_set_status(outlink, AVERROR_EOF, s->eof_pts + s->pts_offset);
270  return 0;
271  }
272 
273  if (!s->eof && (!s->size ||
274  (s->nb_samples < s->size) ||
275  (s->nb_samples >= s->size && s->loop == 0))) {
277  } else if (s->loop && s->nb_samples == s->size) {
278  return arequest_frame(outlink);
279  }
280 
281  return FFERROR_NOT_READY;
282 }
283 
284 static const AVOption aloop_options[] = {
285  { "loop", "number of loops", OFFSET(loop), AV_OPT_TYPE_INT, {.i64 = 0 }, -1, INT_MAX, AFLAGS },
286  { "size", "max number of samples to loop", OFFSET(size), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT32_MAX, AFLAGS },
287  { "start", "set the loop start sample", OFFSET(start), AV_OPT_TYPE_INT64, {.i64 = 0 }, -1, INT64_MAX, AFLAGS },
288  { "time", "set the loop start time", OFFSET(time), AV_OPT_TYPE_DURATION, {.i64=INT64_MAX}, INT64_MIN, INT64_MAX, AFLAGS },
289  { NULL }
290 };
291 
292 AVFILTER_DEFINE_CLASS(aloop);
293 
294 static const AVFilterPad ainputs[] = {
295  {
296  .name = "default",
297  .type = AVMEDIA_TYPE_AUDIO,
298  .config_props = aconfig_input,
299  },
300 };
301 
302 const AVFilter ff_af_aloop = {
303  .name = "aloop",
304  .description = NULL_IF_CONFIG_SMALL("Loop audio samples."),
305  .priv_size = sizeof(LoopContext),
306  .priv_class = &aloop_class,
307  .activate = aactivate,
308  .uninit = auninit,
309  FILTER_INPUTS(ainputs),
311 };
312 #endif /* CONFIG_ALOOP_FILTER */
313 
314 #if CONFIG_LOOP_FILTER
315 
316 static av_cold int init(AVFilterContext *ctx)
317 {
318  LoopContext *s = ctx->priv;
319 
320  s->time_pts = AV_NOPTS_VALUE;
321 
322  s->frames = av_calloc(s->size, sizeof(*s->frames));
323  if (!s->frames)
324  return AVERROR(ENOMEM);
325 
326  check_size(ctx);
327 
328  return 0;
329 }
330 
331 static void free_frames(AVFilterContext *ctx)
332 {
333  LoopContext *s = ctx->priv;
334 
335  for (int i = 0; i < s->nb_frames; i++)
336  av_frame_free(&s->frames[i]);
337 }
338 
339 static av_cold void uninit(AVFilterContext *ctx)
340 {
341  LoopContext *s = ctx->priv;
342 
343  free_frames(ctx);
344  av_freep(&s->frames);
345  s->nb_frames = 0;
346 }
347 
348 static int push_frame(AVFilterContext *ctx)
349 {
350  AVFilterLink *outlink = ctx->outputs[0];
351  LoopContext *s = ctx->priv;
352  AVFrame *out;
353  int ret;
354 
355  out = av_frame_clone(s->frames[s->current_frame]);
356  if (!out)
357  return AVERROR(ENOMEM);
358  out->pts += s->pts_offset;
359  ret = ff_filter_frame(outlink, out);
360  s->current_frame++;
361 
362  if (s->current_frame >= s->nb_frames) {
363  s->current_frame = 0;
364 
365  s->pts_offset += s->duration;
366  if (s->loop > 0)
367  s->loop--;
368  if (s->loop == 0)
369  free_frames(ctx);
370  }
371 
372  return ret;
373 }
374 
376 {
377  AVFilterContext *ctx = inlink->dst;
378  AVFilterLink *outlink = ctx->outputs[0];
379  LoopContext *s = ctx->priv;
380  int64_t duration;
381  int ret = 0;
382 
383  if (((s->start >= 0 && inlink->frame_count_out >= s->start) ||
384  (s->time_pts != AV_NOPTS_VALUE &&
385  frame->pts >= s->time_pts)) &&
386  s->size > 0 && s->loop != 0) {
387  if (s->nb_frames < s->size) {
388  s->frames[s->nb_frames] = av_frame_clone(frame);
389  if (!s->frames[s->nb_frames]) {
391  return AVERROR(ENOMEM);
392  }
393  s->nb_frames++;
394  if (frame->duration)
395  duration = frame->duration;
396  else
397  duration = av_rescale_q(1, av_inv_q(outlink->frame_rate), outlink->time_base);
398  s->duration += duration;
399  s->pts_offset = s->duration;
400  ret = ff_filter_frame(outlink, frame);
401  } else {
403  ret = push_frame(ctx);
404  }
405  } else {
406  frame->pts += s->pts_offset - s->duration;
407  ret = ff_filter_frame(outlink, frame);
408  }
409 
410  return ret;
411 }
412 
413 static int activate(AVFilterContext *ctx)
414 {
415  AVFilterLink *inlink = ctx->inputs[0];
416  AVFilterLink *outlink = ctx->outputs[0];
417  LoopContext *s = ctx->priv;
418  AVFrame *frame = NULL;
419  int ret, status;
420 
421  ret = ff_outlink_get_status(outlink);
422  if (ret) {
424  free_frames(ctx);
425  return 0;
426  }
427 
428  update_time(ctx, inlink->time_base);
429 
430  if (!s->eof && (s->nb_frames < s->size || !s->loop || !s->size)) {
432  if (ret < 0)
433  return ret;
434  if (ret > 0)
435  return filter_frame(inlink, frame);
436  }
437 
438  if (!s->eof && ff_inlink_acknowledge_status(inlink, &status, &s->eof_pts)) {
439  if (status == AVERROR_EOF) {
440  s->size = s->nb_frames;
441  s->eof = 1;
442  }
443  }
444 
445  if (s->eof && (!s->loop || !s->size)) {
446  ff_outlink_set_status(outlink, AVERROR_EOF, s->eof_pts + s->pts_offset);
447  free_frames(ctx);
448  return 0;
449  }
450 
451  if (!s->eof && (!s->size ||
452  (s->nb_frames < s->size) ||
453  (s->nb_frames >= s->size && s->loop == 0))) {
455  } else if (s->loop && s->nb_frames == s->size) {
456  return push_frame(ctx);
457  }
458 
459  return FFERROR_NOT_READY;
460 }
461 
462 static const AVOption loop_options[] = {
463  { "loop", "number of loops", OFFSET(loop), AV_OPT_TYPE_INT, {.i64 = 0 }, -1, INT_MAX, VFLAGS },
464  { "size", "max number of frames to loop", OFFSET(size), AV_OPT_TYPE_INT64, {.i64 = 0 }, 0, INT16_MAX, VFLAGS },
465  { "start", "set the loop start frame", OFFSET(start), AV_OPT_TYPE_INT64, {.i64 = 0 }, -1, INT64_MAX, VFLAGS },
466  { "time", "set the loop start time", OFFSET(time), AV_OPT_TYPE_DURATION, {.i64=INT64_MAX}, INT64_MIN, INT64_MAX, VFLAGS },
467  { NULL }
468 };
469 
471 
472 const AVFilter ff_vf_loop = {
473  .name = "loop",
474  .description = NULL_IF_CONFIG_SMALL("Loop video frames."),
475  .priv_size = sizeof(LoopContext),
476  .priv_class = &loop_class,
477  .init = init,
478  .uninit = uninit,
479  .activate = activate,
482 };
483 #endif /* CONFIG_LOOP_FILTER */
av_audio_fifo_free
void av_audio_fifo_free(AVAudioFifo *af)
Free an AVAudioFifo.
Definition: audio_fifo.c:48
ff_get_audio_buffer
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:97
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
out
FILE * out
Definition: movenc.c:55
push_samples
static int push_samples(ATempoContext *atempo, AVFilterLink *outlink, int n_out)
Definition: af_atempo.c:1027
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1015
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
check_size
static void check_size(AVFilterContext *ctx)
Definition: f_loop.c:61
FFERROR_NOT_READY
return FFERROR_NOT_READY
Definition: filter_design.txt:204
av_audio_fifo_write
int av_audio_fifo_write(AVAudioFifo *af, void *const *data, int nb_samples)
Write data to an AVAudioFifo.
Definition: audio_fifo.c:119
AV_TIME_BASE_Q
#define AV_TIME_BASE_Q
Internal time base represented as fractional value.
Definition: avutil.h:264
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
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:160
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
AVOption
AVOption.
Definition: opt.h:357
AV_OPT_TYPE_DURATION
@ AV_OPT_TYPE_DURATION
Definition: opt.h:259
ff_request_frame
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:463
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:170
video.h
LoopContext::nb_frames
int nb_frames
Definition: f_loop.c:39
LoopContext
Definition: f_loop.c:33
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
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:1442
AVAudioFifo
Context for an Audio FIFO Buffer.
Definition: audio_fifo.c:37
LoopContext::nb_samples
int64_t nb_samples
Definition: f_loop.c:44
av_audio_fifo_drain
int av_audio_fifo_drain(AVAudioFifo *af, int nb_samples)
Drain data from an AVAudioFifo.
Definition: audio_fifo.c:195
LoopContext::pts
int64_t pts
Definition: f_loop.c:52
loop
static int loop
Definition: ffplay.c:335
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:33
push_frame
static int push_frame(AVFilterLink *outlink)
Definition: af_apad.c:92
av_cold
#define av_cold
Definition: attributes.h:90
LoopContext::pts_offset
int64_t pts_offset
Definition: f_loop.c:53
ff_video_default_filterpad
const AVFilterPad ff_video_default_filterpad[1]
An AVFilterPad array whose only entry has name "default" and is of type AVMEDIA_TYPE_VIDEO.
Definition: video.c:37
duration
int64_t duration
Definition: movenc.c:65
ff_outlink_set_status
static void ff_outlink_set_status(AVFilterLink *link, int status, int64_t pts)
Set the status field of a link from the source filter.
Definition: filters.h:189
LoopContext::size
int64_t size
Definition: f_loop.c:49
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
LoopContext::duration
int64_t duration
Definition: f_loop.c:42
AV_OPT_TYPE_INT64
@ AV_OPT_TYPE_INT64
Definition: opt.h:246
filters.h
ctx
AVFormatContext * ctx
Definition: movenc.c:49
av_frame_clone
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:593
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
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:182
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
ff_inlink_consume_samples
int ff_inlink_consume_samples(AVFilterLink *link, unsigned min, unsigned max, AVFrame **rframe)
Take samples from the link's FIFO and update the link's stats.
Definition: avfilter.c:1462
NULL
#define NULL
Definition: coverity.c:32
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
av_audio_fifo_alloc
AVAudioFifo * av_audio_fifo_alloc(enum AVSampleFormat sample_fmt, int channels, int nb_samples)
Allocate an AVAudioFifo.
Definition: audio_fifo.c:62
activate
filter_frame For filters that do not use the activate() callback
LoopContext::loop
int loop
Definition: f_loop.c:47
ff_audio_default_filterpad
const AVFilterPad ff_audio_default_filterpad[1]
An AVFilterPad array whose only entry has name "default" and is of type AVMEDIA_TYPE_AUDIO.
Definition: audio.c:33
AFLAGS
#define AFLAGS
Definition: f_loop.c:57
filter_frame
static int filter_frame(DBEDecodeContext *s, AVFrame *frame)
Definition: dolby_e.c:1059
ff_inlink_acknowledge_status
int ff_inlink_acknowledge_status(AVFilterLink *link, int *rstatus, int64_t *rpts)
Test and acknowledge the change of status on the link.
Definition: avfilter.c:1389
LoopContext::time
int64_t time
Definition: f_loop.c:51
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:366
ff_inlink_set_status
void ff_inlink_set_status(AVFilterLink *link, int status)
Set the status on an input link.
Definition: avfilter.c:1577
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:94
av_audio_fifo_read
int av_audio_fifo_read(AVAudioFifo *af, void *const *data, int nb_samples)
Read data from an AVAudioFifo.
Definition: audio_fifo.c:175
size
int size
Definition: twinvq_data.h:10344
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
LoopContext::current_frame
int current_frame
Definition: f_loop.c:40
FF_FILTER_FORWARD_WANTED
FF_FILTER_FORWARD_WANTED(outlink, inlink)
av_audio_fifo_size
int av_audio_fifo_size(AVAudioFifo *af)
Get the current number of samples in the AVAudioFifo available for reading.
Definition: audio_fifo.c:222
internal.h
AVFILTER_DEFINE_CLASS
#define AVFILTER_DEFINE_CLASS(fname)
Definition: internal.h:323
ff_af_aloop
const AVFilter ff_af_aloop
uninit
static void uninit(AVBSFContext *ctx)
Definition: pcm_rechunk.c:68
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
internal.h
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
audio_fifo.h
av_inv_q
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:39
av_calloc
void * av_calloc(size_t nmemb, size_t size)
Definition: mem.c:264
LoopContext::ignored_samples
int64_t ignored_samples
Definition: f_loop.c:45
AVFilter
Filter definition.
Definition: avfilter.h:166
LoopContext::frames
AVFrame ** frames
Definition: f_loop.c:38
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
LoopContext::eof_pts
int64_t eof_pts
Definition: f_loop.c:54
LoopContext::current_sample
int64_t current_sample
Definition: f_loop.c:43
free_frames
static void free_frames(int nb_inputs, AVFrame **input_frames)
Definition: af_amerge.c:211
LoopContext::eof
int eof
Definition: f_loop.c:48
status
ov_status_e status
Definition: dnn_backend_openvino.c:101
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:245
avfilter.h
OFFSET
#define OFFSET(x)
Definition: f_loop.c:59
LoopContext::left
AVAudioFifo * left
Definition: f_loop.c:37
update_time
static void update_time(AVFilterContext *ctx, AVRational tb)
Definition: f_loop.c:70
LoopContext::fifo
AVAudioFifo * fifo
Definition: f_loop.c:36
ff_outlink_get_status
int ff_outlink_get_status(AVFilterLink *link)
Get the status on an output link.
Definition: avfilter.c:1593
AVFilterContext
An instance of a filter.
Definition: avfilter.h:407
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
mem.h
audio.h
ff_vf_loop
const AVFilter ff_vf_loop
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:183
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
LoopContext::start
int64_t start
Definition: f_loop.c:50
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
LoopContext::time_pts
int64_t time_pts
Definition: f_loop.c:41
VFLAGS
#define VFLAGS
Definition: f_loop.c:58
av_audio_fifo_peek_at
int av_audio_fifo_peek_at(const AVAudioFifo *af, void *const *data, int nb_samples, int offset)
Peek data from an AVAudioFifo.
Definition: audio_fifo.c:150