FFmpeg
af_afreqshift.c
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1 /*
2  * Copyright (c) Paul B Mahol
3  * Copyright (c) Laurent de Soras, 2005
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 
23 #include "libavutil/ffmath.h"
24 #include "libavutil/opt.h"
25 #include "avfilter.h"
26 #include "audio.h"
27 #include "formats.h"
28 
29 #define NB_COEFS 16
30 
31 typedef struct AFreqShift {
32  const AVClass *class;
33 
34  double shift;
35  double level;
36 
37  double cd[NB_COEFS];
38  float cf[NB_COEFS];
39 
40  int64_t in_samples;
41 
44 
46  int channel,
47  AVFrame *in, AVFrame *out);
48 } AFreqShift;
49 
51 {
54  static const enum AVSampleFormat sample_fmts[] = {
58  };
59  int ret;
60 
62  if (!formats)
63  return AVERROR(ENOMEM);
65  if (ret < 0)
66  return ret;
67 
69  if (!layouts)
70  return AVERROR(ENOMEM);
71 
73  if (ret < 0)
74  return ret;
75 
78 }
79 
80 #define PFILTER(name, type, sin, cos, cc) \
81 static void pfilter_channel_## name(AVFilterContext *ctx, \
82  int ch, \
83  AVFrame *in, AVFrame *out) \
84 { \
85  AFreqShift *s = ctx->priv; \
86  const int nb_samples = in->nb_samples; \
87  const type *src = (const type *)in->extended_data[ch]; \
88  type *dst = (type *)out->extended_data[ch]; \
89  type *i1 = (type *)s->i1->extended_data[ch]; \
90  type *o1 = (type *)s->o1->extended_data[ch]; \
91  type *i2 = (type *)s->i2->extended_data[ch]; \
92  type *o2 = (type *)s->o2->extended_data[ch]; \
93  const type *c = s->cc; \
94  const type level = s->level; \
95  type shift = s->shift * M_PI; \
96  type cos_theta = cos(shift); \
97  type sin_theta = sin(shift); \
98  \
99  for (int n = 0; n < nb_samples; n++) { \
100  type xn1 = src[n], xn2 = src[n]; \
101  type I, Q; \
102  \
103  for (int j = 0; j < NB_COEFS / 2; j++) { \
104  I = c[j] * (xn1 + o2[j]) - i2[j]; \
105  i2[j] = i1[j]; \
106  i1[j] = xn1; \
107  o2[j] = o1[j]; \
108  o1[j] = I; \
109  xn1 = I; \
110  } \
111  \
112  for (int j = NB_COEFS / 2; j < NB_COEFS; j++) { \
113  Q = c[j] * (xn2 + o2[j]) - i2[j]; \
114  i2[j] = i1[j]; \
115  i1[j] = xn2; \
116  o2[j] = o1[j]; \
117  o1[j] = Q; \
118  xn2 = Q; \
119  } \
120  Q = o2[NB_COEFS - 1]; \
121  \
122  dst[n] = (I * cos_theta - Q * sin_theta) * level; \
123  } \
124 }
125 
126 PFILTER(flt, float, sin, cos, cf)
127 PFILTER(dbl, double, sin, cos, cd)
128 
129 #define FFILTER(name, type, sin, cos, fmod, cc) \
130 static void ffilter_channel_## name(AVFilterContext *ctx, \
131  int ch, \
132  AVFrame *in, AVFrame *out) \
133 { \
134  AFreqShift *s = ctx->priv; \
135  const int nb_samples = in->nb_samples; \
136  const type *src = (const type *)in->extended_data[ch]; \
137  type *dst = (type *)out->extended_data[ch]; \
138  type *i1 = (type *)s->i1->extended_data[ch]; \
139  type *o1 = (type *)s->o1->extended_data[ch]; \
140  type *i2 = (type *)s->i2->extended_data[ch]; \
141  type *o2 = (type *)s->o2->extended_data[ch]; \
142  const type *c = s->cc; \
143  const type level = s->level; \
144  type ts = 1. / in->sample_rate; \
145  type shift = s->shift; \
146  int64_t N = s->in_samples; \
147  \
148  for (int n = 0; n < nb_samples; n++) { \
149  type xn1 = src[n], xn2 = src[n]; \
150  type I, Q, theta; \
151  \
152  for (int j = 0; j < NB_COEFS / 2; j++) { \
153  I = c[j] * (xn1 + o2[j]) - i2[j]; \
154  i2[j] = i1[j]; \
155  i1[j] = xn1; \
156  o2[j] = o1[j]; \
157  o1[j] = I; \
158  xn1 = I; \
159  } \
160  \
161  for (int j = NB_COEFS / 2; j < NB_COEFS; j++) { \
162  Q = c[j] * (xn2 + o2[j]) - i2[j]; \
163  i2[j] = i1[j]; \
164  i1[j] = xn2; \
165  o2[j] = o1[j]; \
166  o1[j] = Q; \
167  xn2 = Q; \
168  } \
169  Q = o2[NB_COEFS - 1]; \
170  \
171  theta = 2. * M_PI * fmod(shift * (N + n) * ts, 1.); \
172  dst[n] = (I * cos(theta) - Q * sin(theta)) * level; \
173  } \
174 }
175 
176 FFILTER(flt, float, sinf, cosf, fmodf, cf)
177 FFILTER(dbl, double, sin, cos, fmod, cd)
178 
179 static void compute_transition_param(double *K, double *Q, double transition)
180 {
181  double kksqrt, e, e2, e4, k, q;
182 
183  k = tan((1. - transition * 2.) * M_PI / 4.);
184  k *= k;
185  kksqrt = pow(1 - k * k, 0.25);
186  e = 0.5 * (1. - kksqrt) / (1. + kksqrt);
187  e2 = e * e;
188  e4 = e2 * e2;
189  q = e * (1. + e4 * (2. + e4 * (15. + 150. * e4)));
190 
191  *Q = q;
192  *K = k;
193 }
194 
195 static double ipowp(double x, int64_t n)
196 {
197  double z = 1.;
198 
199  while (n != 0) {
200  if (n & 1)
201  z *= x;
202  n >>= 1;
203  x *= x;
204  }
205 
206  return z;
207 }
208 
209 static double compute_acc_num(double q, int order, int c)
210 {
211  int64_t i = 0;
212  int j = 1;
213  double acc = 0.;
214  double q_ii1;
215 
216  do {
217  q_ii1 = ipowp(q, i * (i + 1));
218  q_ii1 *= sin((i * 2 + 1) * c * M_PI / order) * j;
219  acc += q_ii1;
220 
221  j = -j;
222  i++;
223  } while (fabs(q_ii1) > 1e-100);
224 
225  return acc;
226 }
227 
228 static double compute_acc_den(double q, int order, int c)
229 {
230  int64_t i = 1;
231  int j = -1;
232  double acc = 0.;
233  double q_i2;
234 
235  do {
236  q_i2 = ipowp(q, i * i);
237  q_i2 *= cos(i * 2 * c * M_PI / order) * j;
238  acc += q_i2;
239 
240  j = -j;
241  i++;
242  } while (fabs(q_i2) > 1e-100);
243 
244  return acc;
245 }
246 
247 static double compute_coef(int index, double k, double q, int order)
248 {
249  const int c = index + 1;
250  const double num = compute_acc_num(q, order, c) * pow(q, 0.25);
251  const double den = compute_acc_den(q, order, c) + 0.5;
252  const double ww = num / den;
253  const double wwsq = ww * ww;
254 
255  const double x = sqrt((1 - wwsq * k) * (1 - wwsq / k)) / (1 + wwsq);
256  const double coef = (1 - x) / (1 + x);
257 
258  return coef;
259 }
260 
261 static void compute_coefs(double *coef_arrd, float *coef_arrf, int nbr_coefs, double transition)
262 {
263  const int order = nbr_coefs * 2 + 1;
264  double k, q;
265 
266  compute_transition_param(&k, &q, transition);
267 
268  for (int n = 0; n < nbr_coefs; n++) {
269  const int idx = (n / 2) + (n & 1) * nbr_coefs / 2;
270 
271  coef_arrd[idx] = compute_coef(n, k, q, order);
272  coef_arrf[idx] = coef_arrd[idx];
273  }
274 }
275 
277 {
278  AVFilterContext *ctx = inlink->dst;
279  AFreqShift *s = ctx->priv;
280 
281  compute_coefs(s->cd, s->cf, NB_COEFS, 2. * 20. / inlink->sample_rate);
282 
287  if (!s->i1 || !s->o1 || !s->i2 || !s->o2)
288  return AVERROR(ENOMEM);
289 
290  if (inlink->format == AV_SAMPLE_FMT_DBLP) {
291  if (!strcmp(ctx->filter->name, "afreqshift"))
292  s->filter_channel = ffilter_channel_dbl;
293  else
294  s->filter_channel = pfilter_channel_dbl;
295  } else {
296  if (!strcmp(ctx->filter->name, "afreqshift"))
297  s->filter_channel = ffilter_channel_flt;
298  else
299  s->filter_channel = pfilter_channel_flt;
300  }
301 
302  return 0;
303 }
304 
305 typedef struct ThreadData {
306  AVFrame *in, *out;
307 } ThreadData;
308 
309 static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
310 {
311  AFreqShift *s = ctx->priv;
312  ThreadData *td = arg;
313  AVFrame *out = td->out;
314  AVFrame *in = td->in;
315  const int start = (in->channels * jobnr) / nb_jobs;
316  const int end = (in->channels * (jobnr+1)) / nb_jobs;
317 
318  for (int ch = start; ch < end; ch++)
319  s->filter_channel(ctx, ch, in, out);
320 
321  return 0;
322 }
323 
325 {
326  AVFilterContext *ctx = inlink->dst;
327  AVFilterLink *outlink = ctx->outputs[0];
328  AFreqShift *s = ctx->priv;
329  AVFrame *out;
330  ThreadData td;
331 
332  if (av_frame_is_writable(in)) {
333  out = in;
334  } else {
335  out = ff_get_audio_buffer(outlink, in->nb_samples);
336  if (!out) {
337  av_frame_free(&in);
338  return AVERROR(ENOMEM);
339  }
341  }
342 
343  td.in = in; td.out = out;
344  ctx->internal->execute(ctx, filter_channels, &td, NULL, FFMIN(inlink->channels,
346 
347  s->in_samples += in->nb_samples;
348 
349  if (out != in)
350  av_frame_free(&in);
351  return ff_filter_frame(outlink, out);
352 }
353 
355 {
356  AFreqShift *s = ctx->priv;
357 
358  av_frame_free(&s->i1);
359  av_frame_free(&s->o1);
360  av_frame_free(&s->i2);
361  av_frame_free(&s->o2);
362 }
363 
364 #define OFFSET(x) offsetof(AFreqShift, x)
365 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
366 
367 static const AVOption afreqshift_options[] = {
368  { "shift", "set frequency shift", OFFSET(shift), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -INT_MAX, INT_MAX, FLAGS },
369  { "level", "set output level", OFFSET(level), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, 1.0, FLAGS },
370  { NULL }
371 };
372 
373 AVFILTER_DEFINE_CLASS(afreqshift);
374 
375 static const AVFilterPad inputs[] = {
376  {
377  .name = "default",
378  .type = AVMEDIA_TYPE_AUDIO,
379  .filter_frame = filter_frame,
380  .config_props = config_input,
381  },
382  { NULL }
383 };
384 
385 static const AVFilterPad outputs[] = {
386  {
387  .name = "default",
388  .type = AVMEDIA_TYPE_AUDIO,
389  },
390  { NULL }
391 };
392 
394  .name = "afreqshift",
395  .description = NULL_IF_CONFIG_SMALL("Apply frequency shifting to input audio."),
396  .query_formats = query_formats,
397  .priv_size = sizeof(AFreqShift),
398  .priv_class = &afreqshift_class,
399  .uninit = uninit,
400  .inputs = inputs,
401  .outputs = outputs,
405 };
406 
407 static const AVOption aphaseshift_options[] = {
408  { "shift", "set phase shift", OFFSET(shift), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1.0, 1.0, FLAGS },
409  { "level", "set output level",OFFSET(level), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, 1.0, FLAGS },
410  { NULL }
411 };
412 
413 AVFILTER_DEFINE_CLASS(aphaseshift);
414 
416  .name = "aphaseshift",
417  .description = NULL_IF_CONFIG_SMALL("Apply phase shifting to input audio."),
418  .query_formats = query_formats,
419  .priv_size = sizeof(AFreqShift),
420  .priv_class = &aphaseshift_class,
421  .uninit = uninit,
422  .inputs = inputs,
423  .outputs = outputs,
427 };
formats
formats
Definition: signature.h: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:86
AV_SAMPLE_FMT_FLTP
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:69
AVFilterChannelLayouts
A list of supported channel layouts.
Definition: formats.h:86
td
#define td
Definition: regdef.h:70
level
uint8_t level
Definition: svq3.c:204
acc
int acc
Definition: yuv2rgb.c:555
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
ff_make_format_list
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:286
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:978
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:953
layouts
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
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
filter_channels
static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: af_afreqshift.c:309
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:111
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:429
inputs
static const AVFilterPad inputs[]
Definition: af_afreqshift.c:375
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
index
fg index
Definition: ffmpeg_filter.c:168
AVOption
AVOption.
Definition: opt.h:248
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:149
ThreadData::out
AVFrame * out
Definition: af_adeclick.c:502
AVFormatContext::internal
AVFormatInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1555
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:65
formats.h
cosf
#define cosf(x)
Definition: libm.h:78
aphaseshift_options
static const AVOption aphaseshift_options[]
Definition: af_afreqshift.c:407
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_afreqshift.c:324
ff_af_aphaseshift
const AVFilter ff_af_aphaseshift
Definition: af_afreqshift.c:415
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:54
av_cold
#define av_cold
Definition: attributes.h:90
ff_set_common_formats
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:580
compute_acc_den
static double compute_acc_den(double q, int order, int c)
Definition: af_afreqshift.c:228
PFILTER
#define PFILTER(name, type, sin, cos, cc)
Definition: af_afreqshift.c:80
s
#define s(width, name)
Definition: cbs_vp9.c:257
AFreqShift
Definition: af_afreqshift.c:31
AVFrame::channels
int channels
number of audio channels, only used for audio.
Definition: frame.h:592
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:227
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ctx
AVFormatContext * ctx
Definition: movenc.c:48
arg
const char * arg
Definition: jacosubdec.c:67
compute_transition_param
static void compute_transition_param(double *K, double *Q, double transition)
Definition: af_afreqshift.c:179
AFreqShift::cf
float cf[NB_COEFS]
Definition: af_afreqshift.c:38
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
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:536
ipowp
static double ipowp(double x, int64_t n)
Definition: af_afreqshift.c:195
OFFSET
#define OFFSET(x)
Definition: af_afreqshift.c:364
AFreqShift::shift
double shift
Definition: af_afreqshift.c:34
sinf
#define sinf(x)
Definition: libm.h:419
AFreqShift::i2
AVFrame * i2
Definition: af_afreqshift.c:43
AFreqShift::level
double level
Definition: af_afreqshift.c:35
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
FFILTER
#define FFILTER(name, type, sin, cos, fmod, cc)
Definition: af_afreqshift.c:129
compute_acc_num
static double compute_acc_num(double q, int order, int c)
Definition: af_afreqshift.c:209
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
process_command
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
Definition: af_acrusher.c:336
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
av_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:472
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_afreqshift.c:276
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:842
FFMIN
#define FFMIN(a, b)
Definition: common.h:105
M_PI
#define M_PI
Definition: mathematics.h:52
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_afreqshift.c:354
AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:126
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:369
i
int i
Definition: input.c:407
AFreqShift::o1
AVFrame * o1
Definition: af_afreqshift.c:42
ff_filter_get_nb_threads
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
Definition: avfilter.c:762
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
ThreadData
Used for passing data between threads.
Definition: dsddec.c:67
AFreqShift::in_samples
int64_t in_samples
Definition: af_afreqshift.c:40
ff_af_afreqshift
const AVFilter ff_af_afreqshift
Definition: af_afreqshift.c:393
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:60
NB_COEFS
#define NB_COEFS
Definition: af_afreqshift.c:29
compute_coefs
static void compute_coefs(double *coef_arrd, float *coef_arrf, int nbr_coefs, double transition)
Definition: af_afreqshift.c:261
AVFilter
Filter definition.
Definition: avfilter.h:145
afreqshift_options
static const AVOption afreqshift_options[]
Definition: af_afreqshift.c:367
ret
ret
Definition: filter_design.txt:187
AFreqShift::filter_channel
void(* filter_channel)(AVFilterContext *ctx, int channel, AVFrame *in, AVFrame *out)
Definition: af_afreqshift.c:45
AFreqShift::o2
AVFrame * o2
Definition: af_afreqshift.c:43
ff_all_samplerates
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:414
outputs
static const AVFilterPad outputs[]
Definition: af_afreqshift.c:385
channel_layout.h
avfilter.h
AV_SAMPLE_FMT_DBLP
@ AV_SAMPLE_FMT_DBLP
double, planar
Definition: samplefmt.h:70
ffmath.h
AVFilterContext
An instance of a filter.
Definition: avfilter.h:333
shift
static int shift(int a, int b)
Definition: sonic.c:83
AVFILTER_FLAG_SLICE_THREADS
#define AVFILTER_FLAG_SLICE_THREADS
The filter supports multithreading by splitting frames into multiple parts and processing them concur...
Definition: avfilter.h:117
audio.h
FLAGS
#define FLAGS
Definition: af_afreqshift.c:365
ThreadData::in
AVFrame * in
Definition: af_adenorm.c:223
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
ff_set_common_samplerates
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:568
query_formats
static int query_formats(AVFilterContext *ctx)
Definition: af_afreqshift.c:50
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(afreqshift)
compute_coef
static double compute_coef(int index, double k, double q, int order)
Definition: af_afreqshift.c:247
channel
channel
Definition: ebur128.h:39
ff_set_common_channel_layouts
int ff_set_common_channel_layouts(AVFilterContext *ctx, AVFilterChannelLayouts *channel_layouts)
A helper for query_formats() which sets all links to the same list of channel layouts/sample rates.
Definition: formats.c:561
AFreqShift::cd
double cd[NB_COEFS]
Definition: af_afreqshift.c:37
AFreqShift::i1
AVFrame * i1
Definition: af_afreqshift.c:42