FFmpeg
asrc_sinc.c
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1 /*
2  * Copyright (c) 2008-2009 Rob Sykes <robs@users.sourceforge.net>
3  * Copyright (c) 2017 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 #include "libavutil/avassert.h"
23 #include "libavutil/channel_layout.h"
24 #include "libavutil/opt.h"
25 #include "libavutil/tx.h"
26 
27 #include "audio.h"
28 #include "avfilter.h"
29 #include "filters.h"
30 #include "formats.h"
31 #include "internal.h"
32 
33 typedef struct SincContext {
34  const AVClass *class;
35 
36  int sample_rate, nb_samples;
37  float att, beta, phase, Fc0, Fc1, tbw0, tbw1;
38  int num_taps[2];
39  int round;
40 
41  int n, rdft_len;
42  float *coeffs;
43  int64_t pts;
44 
45  AVTXContext *tx, *itx;
46  av_tx_fn tx_fn, itx_fn;
47 } SincContext;
48 
49 static int activate(AVFilterContext *ctx)
50 {
51  AVFilterLink *outlink = ctx->outputs[0];
52  SincContext *s = ctx->priv;
53  const float *coeffs = s->coeffs;
54  AVFrame *frame = NULL;
55  int nb_samples;
56 
57  if (!ff_outlink_frame_wanted(outlink))
58  return FFERROR_NOT_READY;
59 
60  nb_samples = FFMIN(s->nb_samples, s->n - s->pts);
61  if (nb_samples <= 0) {
62  ff_outlink_set_status(outlink, AVERROR_EOF, s->pts);
63  return 0;
64  }
65 
66  if (!(frame = ff_get_audio_buffer(outlink, nb_samples)))
67  return AVERROR(ENOMEM);
68 
69  memcpy(frame->data[0], coeffs + s->pts, nb_samples * sizeof(float));
70 
71  frame->pts = s->pts;
72  s->pts += nb_samples;
73 
74  return ff_filter_frame(outlink, frame);
75 }
76 
77 static int query_formats(AVFilterContext *ctx)
78 {
79  SincContext *s = ctx->priv;
80  static const AVChannelLayout chlayouts[] = { AV_CHANNEL_LAYOUT_MONO, { 0 } };
81  int sample_rates[] = { s->sample_rate, -1 };
82  static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_FLT,
83  AV_SAMPLE_FMT_NONE };
84  int ret = ff_set_common_formats_from_list(ctx, sample_fmts);
85  if (ret < 0)
86  return ret;
87 
88  ret = ff_set_common_channel_layouts_from_list(ctx, chlayouts);
89  if (ret < 0)
90  return ret;
91 
92  return ff_set_common_samplerates_from_list(ctx, sample_rates);
93 }
94 
95 static float *make_lpf(int num_taps, float Fc, float beta, float rho,
96  float scale, int dc_norm)
97 {
98  int i, m = num_taps - 1;
99  float *h = av_calloc(num_taps, sizeof(*h)), sum = 0;
100  float mult = scale / av_bessel_i0(beta), mult1 = 1.f / (.5f * m + rho);
101 
102  if (!h)
103  return NULL;
104 
105  av_assert0(Fc >= 0 && Fc <= 1);
106 
107  for (i = 0; i <= m / 2; i++) {
108  float z = i - .5f * m, x = z * M_PI, y = z * mult1;
109  h[i] = x ? sinf(Fc * x) / x : Fc;
110  sum += h[i] *= av_bessel_i0(beta * sqrtf(1.f - y * y)) * mult;
111  if (m - i != i) {
112  h[m - i] = h[i];
113  sum += h[i];
114  }
115  }
116 
117  for (i = 0; dc_norm && i < num_taps; i++)
118  h[i] *= scale / sum;
119 
120  return h;
121 }
122 
123 static float kaiser_beta(float att, float tr_bw)
124 {
125  if (att >= 60.f) {
126  static const float coefs[][4] = {
127  {-6.784957e-10, 1.02856e-05, 0.1087556, -0.8988365 + .001},
128  {-6.897885e-10, 1.027433e-05, 0.10876, -0.8994658 + .002},
129  {-1.000683e-09, 1.030092e-05, 0.1087677, -0.9007898 + .003},
130  {-3.654474e-10, 1.040631e-05, 0.1087085, -0.8977766 + .006},
131  {8.106988e-09, 6.983091e-06, 0.1091387, -0.9172048 + .015},
132  {9.519571e-09, 7.272678e-06, 0.1090068, -0.9140768 + .025},
133  {-5.626821e-09, 1.342186e-05, 0.1083999, -0.9065452 + .05},
134  {-9.965946e-08, 5.073548e-05, 0.1040967, -0.7672778 + .085},
135  {1.604808e-07, -5.856462e-05, 0.1185998, -1.34824 + .1},
136  {-1.511964e-07, 6.363034e-05, 0.1064627, -0.9876665 + .18},
137  };
138  float realm = logf(tr_bw / .0005f) / logf(2.f);
139  float const *c0 = coefs[av_clip((int)realm, 0, FF_ARRAY_ELEMS(coefs) - 1)];
140  float const *c1 = coefs[av_clip(1 + (int)realm, 0, FF_ARRAY_ELEMS(coefs) - 1)];
141  float b0 = ((c0[0] * att + c0[1]) * att + c0[2]) * att + c0[3];
142  float b1 = ((c1[0] * att + c1[1]) * att + c1[2]) * att + c1[3];
143 
144  return b0 + (b1 - b0) * (realm - (int)realm);
145  }
146  if (att > 50.f)
147  return .1102f * (att - 8.7f);
148  if (att > 20.96f)
149  return .58417f * powf(att - 20.96f, .4f) + .07886f * (att - 20.96f);
150  return 0;
151 }
152 
153 static void kaiser_params(float att, float Fc, float tr_bw, float *beta, int *num_taps)
154 {
155  *beta = *beta < 0.f ? kaiser_beta(att, tr_bw * .5f / Fc): *beta;
156  att = att < 60.f ? (att - 7.95f) / (2.285f * M_PI * 2.f) :
157  ((.0007528358f-1.577737e-05 * *beta) * *beta + 0.6248022f) * *beta + .06186902f;
158  *num_taps = !*num_taps ? ceilf(att/tr_bw + 1) : *num_taps;
159 }
160 
161 static float *lpf(float Fn, float Fc, float tbw, int *num_taps, float att, float *beta, int round)
162 {
163  int n = *num_taps;
164 
165  if ((Fc /= Fn) <= 0.f || Fc >= 1.f) {
166  *num_taps = 0;
167  return NULL;
168  }
169 
170  att = att ? att : 120.f;
171 
172  kaiser_params(att, Fc, (tbw ? tbw / Fn : .05f) * .5f, beta, num_taps);
173 
174  if (!n) {
175  n = *num_taps;
176  *num_taps = av_clip(n, 11, 32767);
177  if (round)
178  *num_taps = 1 + 2 * (int)((int)((*num_taps / 2) * Fc + .5f) / Fc + .5f);
179  }
180 
181  return make_lpf(*num_taps |= 1, Fc, *beta, 0.f, 1.f, 0);
182 }
183 
184 static void invert(float *h, int n)
185 {
186  for (int i = 0; i < n; i++)
187  h[i] = -h[i];
188 
189  h[(n - 1) / 2] += 1;
190 }
191 
192 #define SQR(a) ((a) * (a))
193 
194 static float safe_log(float x)
195 {
196  av_assert0(x >= 0);
197  if (x)
198  return logf(x);
199  return -26;
200 }
201 
202 static int fir_to_phase(SincContext *s, float **h, int *len, int *post_len, float phase)
203 {
204  float *pi_wraps, *work, phase1 = (phase > 50.f ? 100.f - phase : phase) / 50.f;
205  int i, work_len, begin, end, imp_peak = 0, peak = 0, ret;
206  float imp_sum = 0, peak_imp_sum = 0, scale = 1.f;
207  float prev_angle2 = 0, cum_2pi = 0, prev_angle1 = 0, cum_1pi = 0;
208 
209  for (i = *len, work_len = 2 * 2 * 8; i > 1; work_len <<= 1, i >>= 1);
210 
211  /* The first part is for work (+2 for (UN)PACK), the latter for pi_wraps. */
212  work = av_calloc((work_len + 2) + (work_len / 2 + 1), sizeof(float));
213  if (!work)
214  return AVERROR(ENOMEM);
215  pi_wraps = &work[work_len + 2];
216 
217  memcpy(work, *h, *len * sizeof(*work));
218 
219  av_tx_uninit(&s->tx);
220  av_tx_uninit(&s->itx);
221  ret = av_tx_init(&s->tx, &s->tx_fn, AV_TX_FLOAT_RDFT, 0, work_len, &scale, AV_TX_INPLACE);
222  if (ret < 0)
223  goto fail;
224  ret = av_tx_init(&s->itx, &s->itx_fn, AV_TX_FLOAT_RDFT, 1, work_len, &scale, AV_TX_INPLACE);
225  if (ret < 0)
226  goto fail;
227 
228  s->tx_fn(s->tx, work, work, sizeof(float)); /* Cepstral: */
229 
230  for (i = 0; i <= work_len; i += 2) {
231  float angle = atan2f(work[i + 1], work[i]);
232  float detect = 2 * M_PI;
233  float delta = angle - prev_angle2;
234  float adjust = detect * ((delta < -detect * .7f) - (delta > detect * .7f));
235 
236  prev_angle2 = angle;
237  cum_2pi += adjust;
238  angle += cum_2pi;
239  detect = M_PI;
240  delta = angle - prev_angle1;
241  adjust = detect * ((delta < -detect * .7f) - (delta > detect * .7f));
242  prev_angle1 = angle;
243  cum_1pi += fabsf(adjust); /* fabs for when 2pi and 1pi have combined */
244  pi_wraps[i >> 1] = cum_1pi;
245 
246  work[i] = safe_log(sqrtf(SQR(work[i]) + SQR(work[i + 1])));
247  work[i + 1] = 0;
248  }
249 
250  s->itx_fn(s->itx, work, work, sizeof(AVComplexFloat));
251 
252  for (i = 0; i < work_len; i++)
253  work[i] *= 2.f / work_len;
254 
255  for (i = 1; i < work_len / 2; i++) { /* Window to reject acausal components */
256  work[i] *= 2;
257  work[i + work_len / 2] = 0;
258  }
259  s->tx_fn(s->tx, work, work, sizeof(float));
260 
261  for (i = 2; i < work_len; i += 2) /* Interpolate between linear & min phase */
262  work[i + 1] = phase1 * i / work_len * pi_wraps[work_len >> 1] + (1 - phase1) * (work[i + 1] + pi_wraps[i >> 1]) - pi_wraps[i >> 1];
263 
264  work[0] = exp(work[0]);
265  work[1] = exp(work[1]);
266  for (i = 2; i < work_len; i += 2) {
267  float x = expf(work[i]);
268 
269  work[i ] = x * cosf(work[i + 1]);
270  work[i + 1] = x * sinf(work[i + 1]);
271  }
272 
273  s->itx_fn(s->itx, work, work, sizeof(AVComplexFloat));
274  for (i = 0; i < work_len; i++)
275  work[i] *= 2.f / work_len;
276 
277  /* Find peak pos. */
278  for (i = 0; i <= (int) (pi_wraps[work_len >> 1] / M_PI + .5f); i++) {
279  imp_sum += work[i];
280  if (fabs(imp_sum) > fabs(peak_imp_sum)) {
281  peak_imp_sum = imp_sum;
282  peak = i;
283  }
284  if (work[i] > work[imp_peak]) /* For debug check only */
285  imp_peak = i;
286  }
287 
288  while (peak && fabsf(work[peak - 1]) > fabsf(work[peak]) && (work[peak - 1] * work[peak] > 0)) {
289  peak--;
290  }
291 
292  if (!phase1) {
293  begin = 0;
294  } else if (phase1 == 1) {
295  begin = peak - *len / 2;
296  } else {
297  begin = (.997f - (2 - phase1) * .22f) * *len + .5f;
298  end = (.997f + (0 - phase1) * .22f) * *len + .5f;
299  begin = peak - (begin & ~3);
300  end = peak + 1 + ((end + 3) & ~3);
301  *len = end - begin;
302  *h = av_realloc_f(*h, *len, sizeof(**h));
303  if (!*h) {
304  av_free(work);
305  return AVERROR(ENOMEM);
306  }
307  }
308 
309  for (i = 0; i < *len; i++) {
310  (*h)[i] = work[(begin + (phase > 50.f ? *len - 1 - i : i) + work_len) & (work_len - 1)];
311  }
312  *post_len = phase > 50 ? peak - begin : begin + *len - (peak + 1);
313 
314  av_log(s, AV_LOG_DEBUG, "%d nPI=%g peak-sum@%i=%g (val@%i=%g); len=%i post=%i (%g%%)\n",
315  work_len, pi_wraps[work_len >> 1] / M_PI, peak, peak_imp_sum, imp_peak,
316  work[imp_peak], *len, *post_len, 100.f - 100.f * *post_len / (*len - 1));
317 
318 fail:
319  av_free(work);
320 
321  return ret;
322 }
323 
324 static int config_output(AVFilterLink *outlink)
325 {
326  AVFilterContext *ctx = outlink->src;
327  SincContext *s = ctx->priv;
328  float Fn = s->sample_rate * .5f;
329  float *h[2];
330  int i, n, post_peak, longer;
331 
332  outlink->sample_rate = s->sample_rate;
333  s->pts = 0;
334 
335  if (s->Fc0 >= Fn || s->Fc1 >= Fn) {
336  av_log(ctx, AV_LOG_ERROR,
337  "filter frequency must be less than %d/2.\n", s->sample_rate);
338  return AVERROR(EINVAL);
339  }
340 
341  h[0] = lpf(Fn, s->Fc0, s->tbw0, &s->num_taps[0], s->att, &s->beta, s->round);
342  h[1] = lpf(Fn, s->Fc1, s->tbw1, &s->num_taps[1], s->att, &s->beta, s->round);
343 
344  if (h[0])
345  invert(h[0], s->num_taps[0]);
346 
347  longer = s->num_taps[1] > s->num_taps[0];
348  n = s->num_taps[longer];
349 
350  if (h[0] && h[1]) {
351  for (i = 0; i < s->num_taps[!longer]; i++)
352  h[longer][i + (n - s->num_taps[!longer]) / 2] += h[!longer][i];
353 
354  if (s->Fc0 < s->Fc1)
355  invert(h[longer], n);
356 
357  av_free(h[!longer]);
358  }
359 
360  if (s->phase != 50.f) {
361  int ret = fir_to_phase(s, &h[longer], &n, &post_peak, s->phase);
362  if (ret < 0)
363  return ret;
364  } else {
365  post_peak = n >> 1;
366  }
367 
368  s->n = 1 << (av_log2(n) + 1);
369  s->rdft_len = 1 << av_log2(n);
370  s->coeffs = av_calloc(s->n, sizeof(*s->coeffs));
371  if (!s->coeffs)
372  return AVERROR(ENOMEM);
373 
374  for (i = 0; i < n; i++)
375  s->coeffs[i] = h[longer][i];
376  av_free(h[longer]);
377 
378  av_tx_uninit(&s->tx);
379  av_tx_uninit(&s->itx);
380 
381  return 0;
382 }
383 
384 static av_cold void uninit(AVFilterContext *ctx)
385 {
386  SincContext *s = ctx->priv;
387 
388  av_freep(&s->coeffs);
389  av_tx_uninit(&s->tx);
390  av_tx_uninit(&s->itx);
391 }
392 
393 static const AVFilterPad sinc_outputs[] = {
394  {
395  .name = "default",
396  .type = AVMEDIA_TYPE_AUDIO,
397  .config_props = config_output,
398  },
399 };
400 
401 #define AF AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
402 #define OFFSET(x) offsetof(SincContext, x)
403 
404 static const AVOption sinc_options[] = {
405  { "sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64=44100}, 1, INT_MAX, AF },
406  { "r", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64=44100}, 1, INT_MAX, AF },
407  { "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, AF },
408  { "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, AF },
409  { "hp", "set high-pass filter frequency", OFFSET(Fc0), AV_OPT_TYPE_FLOAT, {.dbl=0}, 0, INT_MAX, AF },
410  { "lp", "set low-pass filter frequency", OFFSET(Fc1), AV_OPT_TYPE_FLOAT, {.dbl=0}, 0, INT_MAX, AF },
411  { "phase", "set filter phase response", OFFSET(phase), AV_OPT_TYPE_FLOAT, {.dbl=50}, 0, 100, AF },
412  { "beta", "set kaiser window beta", OFFSET(beta), AV_OPT_TYPE_FLOAT, {.dbl=-1}, -1, 256, AF },
413  { "att", "set stop-band attenuation", OFFSET(att), AV_OPT_TYPE_FLOAT, {.dbl=120}, 40, 180, AF },
414  { "round", "enable rounding", OFFSET(round), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, AF },
415  { "hptaps", "set number of taps for high-pass filter", OFFSET(num_taps[0]), AV_OPT_TYPE_INT, {.i64=0}, 0, 32768, AF },
416  { "lptaps", "set number of taps for low-pass filter", OFFSET(num_taps[1]), AV_OPT_TYPE_INT, {.i64=0}, 0, 32768, AF },
417  { NULL }
418 };
419 
420 AVFILTER_DEFINE_CLASS(sinc);
421 
422 const AVFilter ff_asrc_sinc = {
423  .name = "sinc",
424  .description = NULL_IF_CONFIG_SMALL("Generate a sinc kaiser-windowed low-pass, high-pass, band-pass, or band-reject FIR coefficients."),
425  .priv_size = sizeof(SincContext),
426  .priv_class = &sinc_class,
427  .uninit = uninit,
428  .activate = activate,
429  .inputs = NULL,
430  FILTER_OUTPUTS(sinc_outputs),
431  FILTER_QUERY_FUNC(query_formats),
432 };
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_clip
#define av_clip
Definition: common.h:98
SincContext
Definition: asrc_sinc.c:33
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_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:947
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
FFERROR_NOT_READY
return FFERROR_NOT_READY
Definition: filter_design.txt:204
av_bessel_i0
double av_bessel_i0(double x)
0th order modified bessel function of the first kind.
Definition: mathematics.c:257
AVTXContext
Definition: tx_priv.h:235
atan2f
#define atan2f(y, x)
Definition: libm.h:45
int64_t
long long int64_t
Definition: coverity.c:34
ff_set_common_samplerates_from_list
int ff_set_common_samplerates_from_list(AVFilterContext *ctx, const int *samplerates)
Equivalent to ff_set_common_samplerates(ctx, ff_make_format_list(samplerates))
Definition: formats.c:815
SincContext::tx
AVTXContext * tx
Definition: asrc_sinc.c:45
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:344
AVFrame::pts
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:456
kaiser_beta
static float kaiser_beta(float att, float tr_bw)
Definition: asrc_sinc.c:123
SincContext::tx_fn
av_tx_fn tx_fn
Definition: asrc_sinc.c:46
SincContext::itx
AVTXContext * itx
Definition: asrc_sinc.c:45
AVOption
AVOption.
Definition: opt.h:346
FILTER_QUERY_FUNC
#define FILTER_QUERY_FUNC(func)
Definition: internal.h:159
expf
#define expf(x)
Definition: libm.h:283
AF
#define AF
Definition: asrc_sinc.c:401
AVComplexFloat
Definition: tx.h:27
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:170
c1
static const uint64_t c1
Definition: murmur3.c:52
SincContext::sample_rate
int sample_rate
Definition: asrc_sinc.c:36
SincContext::att
float att
Definition: asrc_sinc.c:37
SincContext::nb_samples
int nb_samples
Definition: asrc_sinc.c:36
SincContext::coeffs
float * coeffs
Definition: asrc_sinc.c:42
ceilf
static __device__ float ceilf(float a)
Definition: cuda_runtime.h:175
sample_rate
sample_rate
Definition: ffmpeg_filter.c:409
av_tx_init
av_cold int av_tx_init(AVTXContext **ctx, av_tx_fn *tx, enum AVTXType type, int inv, int len, const void *scale, uint64_t flags)
Initialize a transform context with the given configuration (i)MDCTs with an odd length are currently...
Definition: tx.c:902
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:365
formats.h
lpf
static float * lpf(float Fn, float Fc, float tbw, int *num_taps, float att, float *beta, int round)
Definition: asrc_sinc.c:161
b1
static double b1(void *priv, double x, double y)
Definition: vf_xfade.c:2035
cosf
#define cosf(x)
Definition: libm.h:78
fail
#define fail()
Definition: checkasm.h:179
SincContext::tbw1
float tbw1
Definition: asrc_sinc.c:37
SincContext::Fc1
float Fc1
Definition: asrc_sinc.c:37
SincContext::pts
int64_t pts
Definition: asrc_sinc.c:43
make_lpf
static float * make_lpf(int num_taps, float Fc, float beta, float rho, float scale, int dc_norm)
Definition: asrc_sinc.c:95
fabsf
static __device__ float fabsf(float a)
Definition: cuda_runtime.h:181
OFFSET
#define OFFSET(x)
Definition: asrc_sinc.c:402
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:33
mult
static int16_t mult(Float11 *f1, Float11 *f2)
Definition: g726.c:60
avassert.h
SincContext::rdft_len
int rdft_len
Definition: asrc_sinc.c:41
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
FF_ARRAY_ELEMS
#define FF_ARRAY_ELEMS(a)
Definition: sinewin_tablegen.c:29
av_cold
#define av_cold
Definition: attributes.h:90
av_tx_fn
void(* av_tx_fn)(AVTXContext *s, void *out, void *in, ptrdiff_t stride)
Function pointer to a function to perform the transform.
Definition: tx.h:151
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
s
#define s(width, name)
Definition: cbs_vp9.c:198
adjust
static int adjust(int x, int size)
Definition: mobiclip.c:512
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
SincContext::tbw0
float tbw0
Definition: asrc_sinc.c:37
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:873
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:40
filters.h
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:201
ctx
AVFormatContext * ctx
Definition: movenc.c:48
ff_set_common_channel_layouts_from_list
int ff_set_common_channel_layouts_from_list(AVFilterContext *ctx, const AVChannelLayout *fmts)
Equivalent to ff_set_common_channel_layouts(ctx, ff_make_channel_layout_list(fmts))
Definition: formats.c:797
frame
static AVFrame * frame
Definition: demux_decode.c:54
SincContext::n
int n
Definition: asrc_sinc.c:41
ff_asrc_sinc
const AVFilter ff_asrc_sinc
Definition: asrc_sinc.c:422
SincContext::phase
float phase
Definition: asrc_sinc.c:37
av_realloc_f
#define av_realloc_f(p, o, n)
Definition: tableprint_vlc.h:32
fir_to_phase
static int fir_to_phase(SincContext *s, float **h, int *len, int *post_len, float phase)
Definition: asrc_sinc.c:202
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
sinc_outputs
static const AVFilterPad sinc_outputs[]
Definition: asrc_sinc.c:393
SincContext::round
int round
Definition: asrc_sinc.c:39
AV_TX_INPLACE
@ AV_TX_INPLACE
Allows for in-place transformations, where input == output.
Definition: tx.h:161
work
must be printed separately If there s no standard function for printing the type you the WRITE_1D_FUNC_ARGV macro is a very quick way to create one See libavcodec dv_tablegen c for an example The h file This file should the initialization functions should not do and instead of the variable declarations the generated *_tables h file should be included Since that will be generated in the build the path must be i e not Makefile changes To make the automatic table creation work
Definition: tablegen.txt:66
activate
static int activate(AVFilterContext *ctx)
Definition: asrc_sinc.c:49
sqrtf
static __device__ float sqrtf(float a)
Definition: cuda_runtime.h:184
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: asrc_sinc.c:384
sinf
#define sinf(x)
Definition: libm.h:419
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
exp
int8_t exp
Definition: eval.c:74
kaiser_params
static void kaiser_params(float att, float Fc, float tr_bw, float *beta, int *num_taps)
Definition: asrc_sinc.c:153
SQR
#define SQR(a)
Definition: asrc_sinc.c:192
f
f
Definition: af_crystalizer.c:121
scale
static void scale(int *out, const int *in, const int w, const int h, const int shift)
Definition: vvc_intra.c:291
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:106
powf
#define powf(x, y)
Definition: libm.h:50
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:303
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:56
SincContext::beta
float beta
Definition: asrc_sinc.c:37
M_PI
#define M_PI
Definition: mathematics.h:67
av_tx_uninit
av_cold void av_tx_uninit(AVTXContext **ctx)
Frees a context and sets *ctx to NULL, does nothing when *ctx == NULL.
Definition: tx.c:294
sample_rates
sample_rates
Definition: ffmpeg_filter.c:409
internal.h
AV_OPT_TYPE_FLOAT
@ AV_OPT_TYPE_FLOAT
Definition: opt.h:238
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
round
static av_always_inline av_const double round(double x)
Definition: libm.h:444
invert
static void invert(float *h, int n)
Definition: asrc_sinc.c:184
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
delta
float delta
Definition: vorbis_enc_data.h:430
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
len
int len
Definition: vorbis_enc_data.h:426
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:262
AVFilter
Filter definition.
Definition: avfilter.h:166
ret
ret
Definition: filter_design.txt:187
config_output
static int config_output(AVFilterLink *outlink)
Definition: asrc_sinc.c:324
AV_TX_FLOAT_RDFT
@ AV_TX_FLOAT_RDFT
Real to complex and complex to real DFTs.
Definition: tx.h:90
channel_layout.h
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:235
avfilter.h
SincContext::Fc0
float Fc0
Definition: asrc_sinc.c:37
AVFilterContext
An instance of a filter.
Definition: avfilter.h:407
sinc_options
static const AVOption sinc_options[]
Definition: asrc_sinc.c:404
audio.h
SincContext::num_taps
int num_taps[2]
Definition: asrc_sinc.c:38
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:378
SincContext::itx_fn
av_tx_fn itx_fn
Definition: asrc_sinc.c:46
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:251
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:183
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
safe_log
static float safe_log(float x)
Definition: asrc_sinc.c:194
query_formats
static int query_formats(AVFilterContext *ctx)
Definition: asrc_sinc.c:77
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
b0
static double b0(void *priv, double x, double y)
Definition: vf_xfade.c:2034
h
h
Definition: vp9dsp_template.c:2038
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
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(sinc)
int
int
Definition: ffmpeg_filter.c:409
av_log2
int av_log2(unsigned v)
Definition: intmath.c:26
AV_SAMPLE_FMT_FLT
@ AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:60
tx.h
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