FFmpeg
af_sidechaincompress.c
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1 /*
2  * Copyright (C) 2001-2010 Krzysztof Foltman, Markus Schmidt, Thor Harald Johansen and others
3  * Copyright (c) 2015 Paul B Mahol
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Audio (Sidechain) Compressor filter
25  */
26 
27 #include "libavutil/audio_fifo.h"
29 #include "libavutil/common.h"
30 #include "libavutil/opt.h"
31 
32 #include "audio.h"
33 #include "avfilter.h"
34 #include "filters.h"
35 #include "formats.h"
36 #include "hermite.h"
37 #include "internal.h"
38 
39 typedef struct SidechainCompressContext {
40  const AVClass *class;
41 
42  double level_in;
43  double level_sc;
46  double lin_slope;
47  double ratio;
48  double threshold;
49  double makeup;
50  double mix;
51  double thres;
52  double knee;
53  double knee_start;
54  double knee_stop;
56  double lin_knee_stop;
58  double adj_knee_stop;
61  int link;
62  int detection;
63  int mode;
64 
66  int64_t pts;
68 
69 #define OFFSET(x) offsetof(SidechainCompressContext, x)
70 #define A AV_OPT_FLAG_AUDIO_PARAM
71 #define F AV_OPT_FLAG_FILTERING_PARAM
72 #define R AV_OPT_FLAG_RUNTIME_PARAM
73 
74 static const AVOption options[] = {
75  { "level_in", "set input gain", OFFSET(level_in), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.015625, 64, A|F|R },
76  { "mode", "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, A|F|R, "mode" },
77  { "downward",0, 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, A|F|R, "mode" },
78  { "upward", 0, 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, A|F|R, "mode" },
79  { "threshold", "set threshold", OFFSET(threshold), AV_OPT_TYPE_DOUBLE, {.dbl=0.125}, 0.000976563, 1, A|F|R },
80  { "ratio", "set ratio", OFFSET(ratio), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 1, 20, A|F|R },
81  { "attack", "set attack", OFFSET(attack), AV_OPT_TYPE_DOUBLE, {.dbl=20}, 0.01, 2000, A|F|R },
82  { "release", "set release", OFFSET(release), AV_OPT_TYPE_DOUBLE, {.dbl=250}, 0.01, 9000, A|F|R },
83  { "makeup", "set make up gain", OFFSET(makeup), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 1, 64, A|F|R },
84  { "knee", "set knee", OFFSET(knee), AV_OPT_TYPE_DOUBLE, {.dbl=2.82843}, 1, 8, A|F|R },
85  { "link", "set link type", OFFSET(link), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, A|F|R, "link" },
86  { "average", 0, 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, A|F|R, "link" },
87  { "maximum", 0, 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, A|F|R, "link" },
88  { "detection", "set detection", OFFSET(detection), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, A|F|R, "detection" },
89  { "peak", 0, 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, A|F|R, "detection" },
90  { "rms", 0, 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, A|F|R, "detection" },
91  { "level_sc", "set sidechain gain", OFFSET(level_sc), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.015625, 64, A|F|R },
92  { "mix", "set mix", OFFSET(mix), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, A|F|R },
93  { NULL }
94 };
95 
96 AVFILTER_DEFINE_CLASS_EXT(sidechaincompress_acompressor,
97  "acompressor/sidechaincompress",
98  options);
99 
100 // A fake infinity value (because real infinity may break some hosts)
101 #define FAKE_INFINITY (65536.0 * 65536.0)
102 
103 // Check for infinity (with appropriate-ish tolerance)
104 #define IS_FAKE_INFINITY(value) (fabs(value-FAKE_INFINITY) < 1.0)
105 
106 static double output_gain(double lin_slope, double ratio, double thres,
107  double knee, double knee_start, double knee_stop,
108  double compressed_knee_start,
109  double compressed_knee_stop,
110  int detection, int mode)
111 {
112  double slope = log(lin_slope);
113  double gain = 0.0;
114  double delta = 0.0;
115 
116  if (detection)
117  slope *= 0.5;
118 
119  if (IS_FAKE_INFINITY(ratio)) {
120  gain = thres;
121  delta = 0.0;
122  } else {
123  gain = (slope - thres) / ratio + thres;
124  delta = 1.0 / ratio;
125  }
126 
127  if (mode) {
128  if (knee > 1.0 && slope > knee_start)
129  gain = hermite_interpolation(slope, knee_stop, knee_start,
130  knee_stop, compressed_knee_start,
131  1.0, delta);
132  } else {
133  if (knee > 1.0 && slope < knee_stop)
134  gain = hermite_interpolation(slope, knee_start, knee_stop,
135  knee_start, compressed_knee_stop,
136  1.0, delta);
137  }
138 
139  return exp(gain - slope);
140 }
141 
143 {
144  AVFilterContext *ctx = outlink->src;
145  SidechainCompressContext *s = ctx->priv;
146 
147  s->thres = log(s->threshold);
148  s->lin_knee_start = s->threshold / sqrt(s->knee);
149  s->lin_knee_stop = s->threshold * sqrt(s->knee);
150  s->adj_knee_start = s->lin_knee_start * s->lin_knee_start;
151  s->adj_knee_stop = s->lin_knee_stop * s->lin_knee_stop;
152  s->knee_start = log(s->lin_knee_start);
153  s->knee_stop = log(s->lin_knee_stop);
154  s->compressed_knee_start = (s->knee_start - s->thres) / s->ratio + s->thres;
155  s->compressed_knee_stop = (s->knee_stop - s->thres) / s->ratio + s->thres;
156 
157  s->attack_coeff = FFMIN(1., 1. / (s->attack * outlink->sample_rate / 4000.));
158  s->release_coeff = FFMIN(1., 1. / (s->release * outlink->sample_rate / 4000.));
159 
160  return 0;
161 }
162 
164  const double *src, double *dst, const double *scsrc, int nb_samples,
165  double level_in, double level_sc,
166  AVFilterLink *inlink, AVFilterLink *sclink)
167 {
168  const double makeup = s->makeup;
169  const double mix = s->mix;
170  int i, c;
171 
172  for (i = 0; i < nb_samples; i++) {
173  double abs_sample, gain = 1.0;
174  double detector;
175  int detected;
176 
177  abs_sample = fabs(scsrc[0] * level_sc);
178 
179  if (s->link == 1) {
180  for (c = 1; c < sclink->channels; c++)
181  abs_sample = FFMAX(fabs(scsrc[c] * level_sc), abs_sample);
182  } else {
183  for (c = 1; c < sclink->channels; c++)
184  abs_sample += fabs(scsrc[c] * level_sc);
185 
186  abs_sample /= sclink->channels;
187  }
188 
189  if (s->detection)
190  abs_sample *= abs_sample;
191 
192  s->lin_slope += (abs_sample - s->lin_slope) * (abs_sample > s->lin_slope ? s->attack_coeff : s->release_coeff);
193 
194  if (s->mode) {
195  detector = (s->detection ? s->adj_knee_stop : s->lin_knee_stop);
196  detected = s->lin_slope < detector;
197  } else {
198  detector = (s->detection ? s->adj_knee_start : s->lin_knee_start);
199  detected = s->lin_slope > detector;
200  }
201 
202  if (s->lin_slope > 0.0 && detected)
203  gain = output_gain(s->lin_slope, s->ratio, s->thres, s->knee,
204  s->knee_start, s->knee_stop,
205  s->compressed_knee_start,
206  s->compressed_knee_stop,
207  s->detection, s->mode);
208 
209  for (c = 0; c < inlink->channels; c++)
210  dst[c] = src[c] * level_in * (gain * makeup * mix + (1. - mix));
211 
212  src += inlink->channels;
213  dst += inlink->channels;
214  scsrc += sclink->channels;
215  }
216 }
217 
218 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
219  char *res, int res_len, int flags)
220 {
221  int ret;
222 
223  ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);
224  if (ret < 0)
225  return ret;
226 
227  compressor_config_output(ctx->outputs[0]);
228 
229  return 0;
230 }
231 
232 #if CONFIG_SIDECHAINCOMPRESS_FILTER
233 static int activate(AVFilterContext *ctx)
234 {
235  SidechainCompressContext *s = ctx->priv;
236  AVFrame *out = NULL, *in[2] = { NULL };
237  int ret, i, nb_samples;
238  double *dst;
239 
241  if ((ret = ff_inlink_consume_frame(ctx->inputs[0], &in[0])) > 0) {
242  av_audio_fifo_write(s->fifo[0], (void **)in[0]->extended_data,
243  in[0]->nb_samples);
244  av_frame_free(&in[0]);
245  }
246  if (ret < 0)
247  return ret;
248  if ((ret = ff_inlink_consume_frame(ctx->inputs[1], &in[1])) > 0) {
249  av_audio_fifo_write(s->fifo[1], (void **)in[1]->extended_data,
250  in[1]->nb_samples);
251  av_frame_free(&in[1]);
252  }
253  if (ret < 0)
254  return ret;
255 
256  nb_samples = FFMIN(av_audio_fifo_size(s->fifo[0]), av_audio_fifo_size(s->fifo[1]));
257  if (nb_samples) {
258  out = ff_get_audio_buffer(ctx->outputs[0], nb_samples);
259  if (!out)
260  return AVERROR(ENOMEM);
261  for (i = 0; i < 2; i++) {
262  in[i] = ff_get_audio_buffer(ctx->inputs[i], nb_samples);
263  if (!in[i]) {
264  av_frame_free(&in[0]);
265  av_frame_free(&in[1]);
266  av_frame_free(&out);
267  return AVERROR(ENOMEM);
268  }
269  av_audio_fifo_read(s->fifo[i], (void **)in[i]->data, nb_samples);
270  }
271 
272  dst = (double *)out->data[0];
273  out->pts = s->pts;
274  s->pts += av_rescale_q(nb_samples, (AVRational){1, ctx->outputs[0]->sample_rate}, ctx->outputs[0]->time_base);
275 
276  compressor(s, (double *)in[0]->data[0], dst,
277  (double *)in[1]->data[0], nb_samples,
278  s->level_in, s->level_sc,
279  ctx->inputs[0], ctx->inputs[1]);
280 
281  av_frame_free(&in[0]);
282  av_frame_free(&in[1]);
283 
284  ret = ff_filter_frame(ctx->outputs[0], out);
285  if (ret < 0)
286  return ret;
287  }
288  FF_FILTER_FORWARD_STATUS(ctx->inputs[0], ctx->outputs[0]);
289  FF_FILTER_FORWARD_STATUS(ctx->inputs[1], ctx->outputs[0]);
290  if (ff_outlink_frame_wanted(ctx->outputs[0])) {
291  if (!av_audio_fifo_size(s->fifo[0]))
292  ff_inlink_request_frame(ctx->inputs[0]);
293  if (!av_audio_fifo_size(s->fifo[1]))
294  ff_inlink_request_frame(ctx->inputs[1]);
295  }
296  return 0;
297 }
298 
299 static int query_formats(AVFilterContext *ctx)
300 {
301  static const enum AVSampleFormat sample_fmts[] = {
304  };
306  &ctx->inputs[1]->outcfg.channel_layouts);
307  if (ret < 0)
308  return ret;
309 
310  /* This will link the channel properties of the main input and the output;
311  * it won't touch the second input as its channel_layouts is already set. */
313  return ret;
314 
316  return ret;
317 
319 }
320 
321 static int config_output(AVFilterLink *outlink)
322 {
323  AVFilterContext *ctx = outlink->src;
324  SidechainCompressContext *s = ctx->priv;
325 
326  outlink->time_base = ctx->inputs[0]->time_base;
327 
328  s->fifo[0] = av_audio_fifo_alloc(ctx->inputs[0]->format, ctx->inputs[0]->channels, 1024);
329  s->fifo[1] = av_audio_fifo_alloc(ctx->inputs[1]->format, ctx->inputs[1]->channels, 1024);
330  if (!s->fifo[0] || !s->fifo[1])
331  return AVERROR(ENOMEM);
332 
333  compressor_config_output(outlink);
334 
335  return 0;
336 }
337 
338 static av_cold void uninit(AVFilterContext *ctx)
339 {
340  SidechainCompressContext *s = ctx->priv;
341 
342  av_audio_fifo_free(s->fifo[0]);
343  av_audio_fifo_free(s->fifo[1]);
344 }
345 
346 static const AVFilterPad sidechaincompress_inputs[] = {
347  {
348  .name = "main",
349  .type = AVMEDIA_TYPE_AUDIO,
350  },{
351  .name = "sidechain",
352  .type = AVMEDIA_TYPE_AUDIO,
353  },
354 };
355 
356 static const AVFilterPad sidechaincompress_outputs[] = {
357  {
358  .name = "default",
359  .type = AVMEDIA_TYPE_AUDIO,
360  .config_props = config_output,
361  },
362 };
363 
365  .name = "sidechaincompress",
366  .description = NULL_IF_CONFIG_SMALL("Sidechain compressor."),
367  .priv_class = &sidechaincompress_acompressor_class,
368  .priv_size = sizeof(SidechainCompressContext),
369  .activate = activate,
370  .uninit = uninit,
371  FILTER_INPUTS(sidechaincompress_inputs),
372  FILTER_OUTPUTS(sidechaincompress_outputs),
374  .process_command = process_command,
375 };
376 #endif /* CONFIG_SIDECHAINCOMPRESS_FILTER */
377 
378 #if CONFIG_ACOMPRESSOR_FILTER
379 static int acompressor_filter_frame(AVFilterLink *inlink, AVFrame *in)
380 {
381  const double *src = (const double *)in->data[0];
382  AVFilterContext *ctx = inlink->dst;
383  SidechainCompressContext *s = ctx->priv;
384  AVFilterLink *outlink = ctx->outputs[0];
385  AVFrame *out;
386  double *dst;
387 
388  if (av_frame_is_writable(in)) {
389  out = in;
390  } else {
391  out = ff_get_audio_buffer(outlink, in->nb_samples);
392  if (!out) {
393  av_frame_free(&in);
394  return AVERROR(ENOMEM);
395  }
397  }
398  dst = (double *)out->data[0];
399 
400  compressor(s, src, dst, src, in->nb_samples,
401  s->level_in, s->level_in,
402  inlink, inlink);
403 
404  if (out != in)
405  av_frame_free(&in);
406  return ff_filter_frame(outlink, out);
407 }
408 
409 static const AVFilterPad acompressor_inputs[] = {
410  {
411  .name = "default",
412  .type = AVMEDIA_TYPE_AUDIO,
413  .filter_frame = acompressor_filter_frame,
414  },
415 };
416 
417 static const AVFilterPad acompressor_outputs[] = {
418  {
419  .name = "default",
420  .type = AVMEDIA_TYPE_AUDIO,
421  .config_props = compressor_config_output,
422  },
423 };
424 
425 const AVFilter ff_af_acompressor = {
426  .name = "acompressor",
427  .description = NULL_IF_CONFIG_SMALL("Audio compressor."),
428  .priv_class = &sidechaincompress_acompressor_class,
429  .priv_size = sizeof(SidechainCompressContext),
430  FILTER_INPUTS(acompressor_inputs),
431  FILTER_OUTPUTS(acompressor_outputs),
433  .process_command = process_command,
434 };
435 #endif /* CONFIG_ACOMPRESSOR_FILTER */
av_audio_fifo_free
void av_audio_fifo_free(AVAudioFifo *af)
Free an AVAudioFifo.
Definition: audio_fifo.c:45
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:88
ff_af_sidechaincompress
const AVFilter ff_af_sidechaincompress
mix
static int mix(int c0, int c1)
Definition: 4xm.c:716
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:54
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1018
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:948
ff_channel_layouts_ref
int ff_channel_layouts_ref(AVFilterChannelLayouts *f, AVFilterChannelLayouts **ref)
Add *ref as a new reference to f.
Definition: formats.c:550
FILTER_SINGLE_SAMPLEFMT
#define FILTER_SINGLE_SAMPLEFMT(sample_fmt_)
Definition: internal.h:184
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:112
ff_all_channel_counts
AVFilterChannelLayouts * ff_all_channel_counts(void)
Construct an AVFilterChannelLayouts coding for any channel layout, with known or unknown disposition.
Definition: formats.c:525
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:310
SidechainCompressContext::adj_knee_stop
double adj_knee_stop
Definition: af_sidechaincompress.c:58
AVOption
AVOption.
Definition: opt.h:247
FILTER_QUERY_FUNC
#define FILTER_QUERY_FUNC(func)
Definition: internal.h:168
data
const char data[16]
Definition: mxf.c:143
ff_set_common_all_samplerates
int ff_set_common_all_samplerates(AVFilterContext *ctx)
Equivalent to ff_set_common_samplerates(ctx, ff_all_samplerates())
Definition: formats.c:689
output_gain
static double output_gain(double lin_slope, double ratio, double thres, double knee, double knee_start, double knee_stop, double compressed_knee_start, double compressed_knee_stop, int detection, int mode)
Definition: af_sidechaincompress.c:106
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:329
formats.h
A
#define A
Definition: af_sidechaincompress.c:70
SidechainCompressContext::lin_knee_stop
double lin_knee_stop
Definition: af_sidechaincompress.c:56
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:1417
FF_FILTER_FORWARD_STATUS_BACK_ALL
#define FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, filter)
Forward the status on an output link to all input links.
Definition: filters.h:212
AVAudioFifo
Context for an Audio FIFO Buffer.
Definition: audio_fifo.c:34
SidechainCompressContext::adj_knee_start
double adj_knee_start
Definition: af_sidechaincompress.c:57
SidechainCompressContext::ratio
double ratio
Definition: af_sidechaincompress.c:47
SidechainCompressContext::release
double release
Definition: af_sidechaincompress.c:45
SidechainCompressContext::pts
int64_t pts
Definition: af_sidechaincompress.c:66
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
options
static const AVOption options[]
Definition: af_sidechaincompress.c:74
compressor
static void compressor(SidechainCompressContext *s, const double *src, double *dst, const double *scsrc, int nb_samples, double level_in, double level_sc, AVFilterLink *inlink, AVFilterLink *sclink)
Definition: af_sidechaincompress.c:163
config_output
static int config_output(AVFilterLink *outlink)
Definition: af_adenorm.c:156
av_cold
#define av_cold
Definition: attributes.h:90
SidechainCompressContext::level_in
double level_in
Definition: af_sidechaincompress.c:42
ff_inlink_request_frame
void ff_inlink_request_frame(AVFilterLink *link)
Mark that a frame is wanted on the link.
Definition: avfilter.c:1534
s
#define s(width, name)
Definition: cbs_vp9.c:257
hermite_interpolation
static double hermite_interpolation(double x, double x0, double x1, double p0, double p1, double m0, double m1)
Definition: hermite.h:22
av_audio_fifo_write
int av_audio_fifo_write(AVAudioFifo *af, void **data, int nb_samples)
Write data to an AVAudioFifo.
Definition: audio_fifo.c:112
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:226
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
SidechainCompressContext::knee_start
double knee_start
Definition: af_sidechaincompress.c:53
ff_set_common_formats_from_list
int ff_set_common_formats_from_list(AVFilterContext *ctx, const int *fmts)
Equivalent to ff_set_common_formats(ctx, ff_make_format_list(fmts))
Definition: formats.c:705
ff_af_acompressor
const AVFilter ff_af_acompressor
filters.h
SidechainCompressContext::mix
double mix
Definition: af_sidechaincompress.c:50
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:141
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:191
link
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 link
Definition: filter_design.txt:23
if
if(ret)
Definition: filter_design.txt:179
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
fabs
static __device__ float fabs(float a)
Definition: cuda_runtime.h:182
NULL
#define NULL
Definition: coverity.c:32
av_frame_copy_props
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:537
SidechainCompressContext::thres
double thres
Definition: af_sidechaincompress.c:51
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:59
activate
filter_frame For filters that do not use the activate() callback
SidechainCompressContext::makeup
double makeup
Definition: af_sidechaincompress.c:49
src
#define src
Definition: vp8dsp.c:255
SidechainCompressContext::compressed_knee_stop
double compressed_knee_stop
Definition: af_sidechaincompress.c:60
ff_set_common_all_channel_counts
int ff_set_common_all_channel_counts(AVFilterContext *ctx)
Equivalent to ff_set_common_channel_layouts(ctx, ff_all_channel_counts())
Definition: formats.c:671
exp
int8_t exp
Definition: eval.c:72
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
OFFSET
#define OFFSET(x)
Definition: af_sidechaincompress.c:69
SidechainCompressContext::link
int link
Definition: af_sidechaincompress.c:61
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:117
hermite.h
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
SidechainCompressContext::mode
int mode
Definition: af_sidechaincompress.c:63
av_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:473
ff_filter_process_command
int ff_filter_process_command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Generic processing of user supplied commands that are set in the same way as the filter options.
Definition: avfilter.c:882
SidechainCompressContext::knee
double knee
Definition: af_sidechaincompress.c:52
SidechainCompressContext::compressed_knee_start
double compressed_knee_start
Definition: af_sidechaincompress.c:59
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:228
internal.h
SidechainCompressContext::detection
int detection
Definition: af_sidechaincompress.c:62
av_audio_fifo_read
int av_audio_fifo_read(AVAudioFifo *af, void **data, int nb_samples)
Read data from an AVAudioFifo.
Definition: audio_fifo.c:181
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:388
R
#define R
Definition: af_sidechaincompress.c:72
compressor_config_output
static int compressor_config_output(AVFilterLink *outlink)
Definition: af_sidechaincompress.c:142
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
common.h
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
SidechainCompressContext::attack_coeff
double attack_coeff
Definition: af_sidechaincompress.c:44
delta
float delta
Definition: vorbis_enc_data.h:430
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
SidechainCompressContext::level_sc
double level_sc
Definition: af_sidechaincompress.c:43
audio_fifo.h
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
SidechainCompressContext::lin_slope
double lin_slope
Definition: af_sidechaincompress.c:46
AVFilter
Filter definition.
Definition: avfilter.h:149
SidechainCompressContext::fifo
AVAudioFifo * fifo[2]
Definition: af_sidechaincompress.c:65
ret
ret
Definition: filter_design.txt:187
SidechainCompressContext
Definition: af_sidechaincompress.c:39
SidechainCompressContext::threshold
double threshold
Definition: af_sidechaincompress.c:48
process_command
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
Definition: af_sidechaincompress.c:218
F
#define F
Definition: af_sidechaincompress.c:71
channel_layout.h
mode
mode
Definition: ebur128.h:83
SidechainCompressContext::knee_stop
double knee_stop
Definition: af_sidechaincompress.c:54
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:224
avfilter.h
AVFilterContext
An instance of a filter.
Definition: avfilter.h:386
AVFILTER_DEFINE_CLASS_EXT
AVFILTER_DEFINE_CLASS_EXT(sidechaincompress_acompressor, "acompressor/sidechaincompress", options)
audio.h
SidechainCompressContext::lin_knee_start
double lin_knee_start
Definition: af_sidechaincompress.c:55
FF_FILTER_FORWARD_STATUS
FF_FILTER_FORWARD_STATUS(inlink, outlink)
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:192
IS_FAKE_INFINITY
#define IS_FAKE_INFINITY(value)
Definition: af_sidechaincompress.c:104
query_formats
static int query_formats(AVFilterContext *ctx)
Definition: aeval.c:243
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
uninit
static av_cold int uninit(AVCodecContext *avctx)
Definition: crystalhd.c:282
ff_outlink_frame_wanted
the definition of that something depends on the semantic of the filter The callback must examine the status of the filter s links and proceed accordingly The status of output links is stored in the status_in and status_out fields and tested by the ff_outlink_frame_wanted() function. If this function returns true
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:64
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:233
SidechainCompressContext::attack
double attack
Definition: af_sidechaincompress.c:44
SidechainCompressContext::release_coeff
double release_coeff
Definition: af_sidechaincompress.c:45