2
* Copyright (c) 2013 Paul B Mahol
3
* Copyright (c) 2006-2008 Rob Sykes <robs@users.sourceforge.net>
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* This file is part of FFmpeg.
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
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* version 2.1 of the License, or (at your option) any later version.
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* 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.
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
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* 2-pole filters designed by Robert Bristow-Johnson <rbj@audioimagination.com>
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* see http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt
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* 1-pole filters based on code (c) 2000 Chris Bagwell <cbagwell@sprynet.com>
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* Algorithms: Recursive single pole low/high pass filter
28
* Reference: The Scientist and Engineer's Guide to Digital Signal Processing
30
* low-pass: output[N] = input[N] * A + output[N-1] * B
31
* X = exp(-2.0 * pi * Fc)
34
* Fc = cutoff freq / sample rate
36
* Mimics an RC low-pass filter:
38
* ---/\/\/\/\----------->
46
* high-pass: output[N] = A0 * input[N] + A1 * input[N-1] + B1 * output[N-1]
47
* X = exp(-2.0 * pi * Fc)
51
* Fc = cutoff freq / sample rate
53
* Mimics an RC high-pass filter:
65
#include "libavutil/avassert.h"
66
#include "libavutil/opt.h"
92
typedef struct ChanCache {
100
enum FilterType filter_type;
101
enum WidthType width_type;
114
void (*filter)(const void *ibuf, void *obuf, int len,
115
double *i1, double *i2, double *o1, double *o2,
116
double b0, double b1, double b2, double a1, double a2);
119
static av_cold int init(AVFilterContext *ctx)
121
BiquadsContext *p = ctx->priv;
123
if (p->filter_type != biquad) {
124
if (p->frequency <= 0 || p->width <= 0) {
125
av_log(ctx, AV_LOG_ERROR, "Invalid frequency %f and/or width %f <= 0\n",
126
p->frequency, p->width);
127
return AVERROR(EINVAL);
134
static int query_formats(AVFilterContext *ctx)
136
AVFilterFormats *formats;
137
AVFilterChannelLayouts *layouts;
138
static const enum AVSampleFormat sample_fmts[] = {
146
layouts = ff_all_channel_layouts();
148
return AVERROR(ENOMEM);
149
ff_set_common_channel_layouts(ctx, layouts);
151
formats = ff_make_format_list(sample_fmts);
153
return AVERROR(ENOMEM);
154
ff_set_common_formats(ctx, formats);
156
formats = ff_all_samplerates();
158
return AVERROR(ENOMEM);
159
ff_set_common_samplerates(ctx, formats);
164
#define BIQUAD_FILTER(name, type, min, max, need_clipping) \
165
static void biquad_## name (const void *input, void *output, int len, \
166
double *in1, double *in2, \
167
double *out1, double *out2, \
168
double b0, double b1, double b2, \
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double a1, double a2) \
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const type *ibuf = input; \
172
type *obuf = output; \
181
for (i = 0; i+1 < len; i++) { \
182
o2 = i2 * b2 + i1 * b1 + ibuf[i] * b0 + o2 * a2 + o1 * a1; \
184
if (need_clipping && o2 < min) { \
185
av_log(NULL, AV_LOG_WARNING, "clipping\n"); \
187
} else if (need_clipping && o2 > max) { \
188
av_log(NULL, AV_LOG_WARNING, "clipping\n"); \
194
o1 = i1 * b2 + i2 * b1 + ibuf[i] * b0 + o1 * a2 + o2 * a1; \
196
if (need_clipping && o1 < min) { \
197
av_log(NULL, AV_LOG_WARNING, "clipping\n"); \
199
} else if (need_clipping && o1 > max) { \
200
av_log(NULL, AV_LOG_WARNING, "clipping\n"); \
207
double o0 = ibuf[i] * b0 + i1 * b1 + i2 * b2 + o1 * a1 + o2 * a2; \
212
if (need_clipping && o0 < min) { \
213
av_log(NULL, AV_LOG_WARNING, "clipping\n"); \
215
} else if (need_clipping && o0 > max) { \
216
av_log(NULL, AV_LOG_WARNING, "clipping\n"); \
228
BIQUAD_FILTER(s16, int16_t, INT16_MIN, INT16_MAX, 1)
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BIQUAD_FILTER(s32, int32_t, INT32_MIN, INT32_MAX, 1)
230
BIQUAD_FILTER(flt, float, -1., 1., 0)
231
BIQUAD_FILTER(dbl, double, -1., 1., 0)
233
static int config_output(AVFilterLink *outlink)
235
AVFilterContext *ctx = outlink->src;
236
BiquadsContext *p = ctx->priv;
237
AVFilterLink *inlink = ctx->inputs[0];
238
double A = exp(p->gain / 40 * log(10.));
239
double w0 = 2 * M_PI * p->frequency / inlink->sample_rate;
243
av_log(ctx, AV_LOG_ERROR,
244
"Invalid frequency %f. Frequency must be less than half the sample-rate %d.\n",
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p->frequency, inlink->sample_rate);
246
return AVERROR(EINVAL);
249
switch (p->width_type) {
254
alpha = sin(w0) / (2 * p->frequency / p->width);
257
alpha = sin(w0) * sinh(log(2.) / 2 * p->width * w0 / sin(w0));
260
alpha = sin(w0) / (2 * p->width);
263
alpha = sin(w0) / 2 * sqrt((A + 1 / A) * (1 / p->width - 1) + 2);
269
switch (p->filter_type) {
273
p->a0 = 1 + alpha / A;
274
p->a1 = -2 * cos(w0);
275
p->a2 = 1 - alpha / A;
276
p->b0 = 1 + alpha * A;
277
p->b1 = -2 * cos(w0);
278
p->b2 = 1 - alpha * A;
281
p->a0 = (A + 1) + (A - 1) * cos(w0) + 2 * sqrt(A) * alpha;
282
p->a1 = -2 * ((A - 1) + (A + 1) * cos(w0));
283
p->a2 = (A + 1) + (A - 1) * cos(w0) - 2 * sqrt(A) * alpha;
284
p->b0 = A * ((A + 1) - (A - 1) * cos(w0) + 2 * sqrt(A) * alpha);
285
p->b1 = 2 * A * ((A - 1) - (A + 1) * cos(w0));
286
p->b2 = A * ((A + 1) - (A - 1) * cos(w0) - 2 * sqrt(A) * alpha);
289
p->a0 = (A + 1) - (A - 1) * cos(w0) + 2 * sqrt(A) * alpha;
290
p->a1 = 2 * ((A - 1) - (A + 1) * cos(w0));
291
p->a2 = (A + 1) - (A - 1) * cos(w0) - 2 * sqrt(A) * alpha;
292
p->b0 = A * ((A + 1) + (A - 1) * cos(w0) + 2 * sqrt(A) * alpha);
293
p->b1 =-2 * A * ((A - 1) + (A + 1) * cos(w0));
294
p->b2 = A * ((A + 1) + (A - 1) * cos(w0) - 2 * sqrt(A) * alpha);
299
p->a1 = -2 * cos(w0);
303
p->b2 = -sin(w0) / 2;
306
p->a1 = -2 * cos(w0);
315
p->a1 = -2 * cos(w0);
318
p->b1 = -2 * cos(w0);
331
p->a1 = -2 * cos(w0);
333
p->b0 = (1 - cos(w0)) / 2;
335
p->b2 = (1 - cos(w0)) / 2;
343
p->b0 = (1 - p->a1) / 2;
348
p->a1 = -2 * cos(w0);
350
p->b0 = (1 + cos(w0)) / 2;
351
p->b1 = -(1 + cos(w0));
352
p->b2 = (1 + cos(w0)) / 2;
357
p->a1 = -2 * cos(w0);
360
p->b1 = -2 * cos(w0);
373
p->cache = av_realloc_f(p->cache, sizeof(ChanCache), inlink->channels);
375
return AVERROR(ENOMEM);
376
memset(p->cache, 0, sizeof(ChanCache) * inlink->channels);
378
switch (inlink->format) {
379
case AV_SAMPLE_FMT_S16P: p->filter = biquad_s16; break;
380
case AV_SAMPLE_FMT_S32P: p->filter = biquad_s32; break;
381
case AV_SAMPLE_FMT_FLTP: p->filter = biquad_flt; break;
382
case AV_SAMPLE_FMT_DBLP: p->filter = biquad_dbl; break;
383
default: av_assert0(0);
389
static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
391
BiquadsContext *p = inlink->dst->priv;
392
AVFilterLink *outlink = inlink->dst->outputs[0];
394
int nb_samples = buf->nb_samples;
397
if (av_frame_is_writable(buf)) {
400
out_buf = ff_get_audio_buffer(inlink, nb_samples);
402
return AVERROR(ENOMEM);
403
av_frame_copy_props(out_buf, buf);
406
for (ch = 0; ch < av_frame_get_channels(buf); ch++)
407
p->filter(buf->extended_data[ch],
408
out_buf->extended_data[ch], nb_samples,
409
&p->cache[ch].i1, &p->cache[ch].i2,
410
&p->cache[ch].o1, &p->cache[ch].o2,
411
p->b0, p->b1, p->b2, p->a1, p->a2);
416
return ff_filter_frame(outlink, out_buf);
419
static av_cold void uninit(AVFilterContext *ctx)
421
BiquadsContext *p = ctx->priv;
426
static const AVFilterPad inputs[] = {
429
.type = AVMEDIA_TYPE_AUDIO,
430
.filter_frame = filter_frame,
435
static const AVFilterPad outputs[] = {
438
.type = AVMEDIA_TYPE_AUDIO,
439
.config_props = config_output,
444
#define OFFSET(x) offsetof(BiquadsContext, x)
445
#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
447
#define DEFINE_BIQUAD_FILTER(name_, description_) \
448
AVFILTER_DEFINE_CLASS(name_); \
449
static av_cold int name_##_init(AVFilterContext *ctx) \
451
BiquadsContext *p = ctx->priv; \
452
p->class = &name_##_class; \
453
p->filter_type = name_; \
457
AVFilter ff_af_##name_ = { \
459
.description = NULL_IF_CONFIG_SMALL(description_), \
460
.priv_size = sizeof(BiquadsContext), \
461
.init = name_##_init, \
463
.query_formats = query_formats, \
465
.outputs = outputs, \
466
.priv_class = &name_##_class, \
469
#if CONFIG_EQUALIZER_FILTER
470
static const AVOption equalizer_options[] = {
471
{"frequency", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=0}, 0, 999999, FLAGS},
472
{"f", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=0}, 0, 999999, FLAGS},
473
{"width_type", "set filter-width type", OFFSET(width_type), AV_OPT_TYPE_INT, {.i64=QFACTOR}, HERTZ, SLOPE, FLAGS, "width_type"},
474
{"h", "Hz", 0, AV_OPT_TYPE_CONST, {.i64=HERTZ}, 0, 0, FLAGS, "width_type"},
475
{"q", "Q-Factor", 0, AV_OPT_TYPE_CONST, {.i64=QFACTOR}, 0, 0, FLAGS, "width_type"},
476
{"o", "octave", 0, AV_OPT_TYPE_CONST, {.i64=OCTAVE}, 0, 0, FLAGS, "width_type"},
477
{"s", "slope", 0, AV_OPT_TYPE_CONST, {.i64=SLOPE}, 0, 0, FLAGS, "width_type"},
478
{"width", "set band-width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 999, FLAGS},
479
{"w", "set band-width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 999, FLAGS},
480
{"gain", "set gain", OFFSET(gain), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -900, 900, FLAGS},
481
{"g", "set gain", OFFSET(gain), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -900, 900, FLAGS},
485
DEFINE_BIQUAD_FILTER(equalizer, "Apply two-pole peaking equalization (EQ) filter.");
486
#endif /* CONFIG_EQUALIZER_FILTER */
487
#if CONFIG_BASS_FILTER
488
static const AVOption bass_options[] = {
489
{"frequency", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=100}, 0, 999999, FLAGS},
490
{"f", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=100}, 0, 999999, FLAGS},
491
{"width_type", "set filter-width type", OFFSET(width_type), AV_OPT_TYPE_INT, {.i64=QFACTOR}, HERTZ, SLOPE, FLAGS, "width_type"},
492
{"h", "Hz", 0, AV_OPT_TYPE_CONST, {.i64=HERTZ}, 0, 0, FLAGS, "width_type"},
493
{"q", "Q-Factor", 0, AV_OPT_TYPE_CONST, {.i64=QFACTOR}, 0, 0, FLAGS, "width_type"},
494
{"o", "octave", 0, AV_OPT_TYPE_CONST, {.i64=OCTAVE}, 0, 0, FLAGS, "width_type"},
495
{"s", "slope", 0, AV_OPT_TYPE_CONST, {.i64=SLOPE}, 0, 0, FLAGS, "width_type"},
496
{"width", "set shelf transition steep", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 99999, FLAGS},
497
{"w", "set shelf transition steep", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 99999, FLAGS},
498
{"gain", "set gain", OFFSET(gain), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -900, 900, FLAGS},
499
{"g", "set gain", OFFSET(gain), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -900, 900, FLAGS},
503
DEFINE_BIQUAD_FILTER(bass, "Boost or cut lower frequencies.");
504
#endif /* CONFIG_BASS_FILTER */
505
#if CONFIG_TREBLE_FILTER
506
static const AVOption treble_options[] = {
507
{"frequency", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
508
{"f", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
509
{"width_type", "set filter-width type", OFFSET(width_type), AV_OPT_TYPE_INT, {.i64=QFACTOR}, HERTZ, SLOPE, FLAGS, "width_type"},
510
{"h", "Hz", 0, AV_OPT_TYPE_CONST, {.i64=HERTZ}, 0, 0, FLAGS, "width_type"},
511
{"q", "Q-Factor", 0, AV_OPT_TYPE_CONST, {.i64=QFACTOR}, 0, 0, FLAGS, "width_type"},
512
{"o", "octave", 0, AV_OPT_TYPE_CONST, {.i64=OCTAVE}, 0, 0, FLAGS, "width_type"},
513
{"s", "slope", 0, AV_OPT_TYPE_CONST, {.i64=SLOPE}, 0, 0, FLAGS, "width_type"},
514
{"width", "set shelf transition steep", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 99999, FLAGS},
515
{"w", "set shelf transition steep", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 99999, FLAGS},
516
{"gain", "set gain", OFFSET(gain), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -900, 900, FLAGS},
517
{"g", "set gain", OFFSET(gain), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -900, 900, FLAGS},
521
DEFINE_BIQUAD_FILTER(treble, "Boost or cut upper frequencies.");
522
#endif /* CONFIG_TREBLE_FILTER */
523
#if CONFIG_BANDPASS_FILTER
524
static const AVOption bandpass_options[] = {
525
{"frequency", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
526
{"f", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
527
{"width_type", "set filter-width type", OFFSET(width_type), AV_OPT_TYPE_INT, {.i64=QFACTOR}, HERTZ, SLOPE, FLAGS, "width_type"},
528
{"h", "Hz", 0, AV_OPT_TYPE_CONST, {.i64=HERTZ}, 0, 0, FLAGS, "width_type"},
529
{"q", "Q-Factor", 0, AV_OPT_TYPE_CONST, {.i64=QFACTOR}, 0, 0, FLAGS, "width_type"},
530
{"o", "octave", 0, AV_OPT_TYPE_CONST, {.i64=OCTAVE}, 0, 0, FLAGS, "width_type"},
531
{"s", "slope", 0, AV_OPT_TYPE_CONST, {.i64=SLOPE}, 0, 0, FLAGS, "width_type"},
532
{"width", "set band-width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 999, FLAGS},
533
{"w", "set band-width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 999, FLAGS},
534
{"csg", "use constant skirt gain", OFFSET(csg), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS},
538
DEFINE_BIQUAD_FILTER(bandpass, "Apply a two-pole Butterworth band-pass filter.");
539
#endif /* CONFIG_BANDPASS_FILTER */
540
#if CONFIG_BANDREJECT_FILTER
541
static const AVOption bandreject_options[] = {
542
{"frequency", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
543
{"f", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
544
{"width_type", "set filter-width type", OFFSET(width_type), AV_OPT_TYPE_INT, {.i64=QFACTOR}, HERTZ, SLOPE, FLAGS, "width_type"},
545
{"h", "Hz", 0, AV_OPT_TYPE_CONST, {.i64=HERTZ}, 0, 0, FLAGS, "width_type"},
546
{"q", "Q-Factor", 0, AV_OPT_TYPE_CONST, {.i64=QFACTOR}, 0, 0, FLAGS, "width_type"},
547
{"o", "octave", 0, AV_OPT_TYPE_CONST, {.i64=OCTAVE}, 0, 0, FLAGS, "width_type"},
548
{"s", "slope", 0, AV_OPT_TYPE_CONST, {.i64=SLOPE}, 0, 0, FLAGS, "width_type"},
549
{"width", "set band-width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 999, FLAGS},
550
{"w", "set band-width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0, 999, FLAGS},
554
DEFINE_BIQUAD_FILTER(bandreject, "Apply a two-pole Butterworth band-reject filter.");
555
#endif /* CONFIG_BANDREJECT_FILTER */
556
#if CONFIG_LOWPASS_FILTER
557
static const AVOption lowpass_options[] = {
558
{"frequency", "set frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=500}, 0, 999999, FLAGS},
559
{"f", "set frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=500}, 0, 999999, FLAGS},
560
{"width_type", "set filter-width type", OFFSET(width_type), AV_OPT_TYPE_INT, {.i64=QFACTOR}, HERTZ, SLOPE, FLAGS, "width_type"},
561
{"h", "Hz", 0, AV_OPT_TYPE_CONST, {.i64=HERTZ}, 0, 0, FLAGS, "width_type"},
562
{"q", "Q-Factor", 0, AV_OPT_TYPE_CONST, {.i64=QFACTOR}, 0, 0, FLAGS, "width_type"},
563
{"o", "octave", 0, AV_OPT_TYPE_CONST, {.i64=OCTAVE}, 0, 0, FLAGS, "width_type"},
564
{"s", "slope", 0, AV_OPT_TYPE_CONST, {.i64=SLOPE}, 0, 0, FLAGS, "width_type"},
565
{"width", "set width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.707}, 0, 99999, FLAGS},
566
{"w", "set width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.707}, 0, 99999, FLAGS},
567
{"poles", "set number of poles", OFFSET(poles), AV_OPT_TYPE_INT, {.i64=2}, 1, 2, FLAGS},
568
{"p", "set number of poles", OFFSET(poles), AV_OPT_TYPE_INT, {.i64=2}, 1, 2, FLAGS},
572
DEFINE_BIQUAD_FILTER(lowpass, "Apply a low-pass filter with 3dB point frequency.");
573
#endif /* CONFIG_LOWPASS_FILTER */
574
#if CONFIG_HIGHPASS_FILTER
575
static const AVOption highpass_options[] = {
576
{"frequency", "set frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
577
{"f", "set frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
578
{"width_type", "set filter-width type", OFFSET(width_type), AV_OPT_TYPE_INT, {.i64=QFACTOR}, HERTZ, SLOPE, FLAGS, "width_type"},
579
{"h", "Hz", 0, AV_OPT_TYPE_CONST, {.i64=HERTZ}, 0, 0, FLAGS, "width_type"},
580
{"q", "Q-Factor", 0, AV_OPT_TYPE_CONST, {.i64=QFACTOR}, 0, 0, FLAGS, "width_type"},
581
{"o", "octave", 0, AV_OPT_TYPE_CONST, {.i64=OCTAVE}, 0, 0, FLAGS, "width_type"},
582
{"s", "slope", 0, AV_OPT_TYPE_CONST, {.i64=SLOPE}, 0, 0, FLAGS, "width_type"},
583
{"width", "set width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.707}, 0, 99999, FLAGS},
584
{"w", "set width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=0.707}, 0, 99999, FLAGS},
585
{"poles", "set number of poles", OFFSET(poles), AV_OPT_TYPE_INT, {.i64=2}, 1, 2, FLAGS},
586
{"p", "set number of poles", OFFSET(poles), AV_OPT_TYPE_INT, {.i64=2}, 1, 2, FLAGS},
590
DEFINE_BIQUAD_FILTER(highpass, "Apply a high-pass filter with 3dB point frequency.");
591
#endif /* CONFIG_HIGHPASS_FILTER */
592
#if CONFIG_ALLPASS_FILTER
593
static const AVOption allpass_options[] = {
594
{"frequency", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
595
{"f", "set central frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=3000}, 0, 999999, FLAGS},
596
{"width_type", "set filter-width type", OFFSET(width_type), AV_OPT_TYPE_INT, {.i64=HERTZ}, HERTZ, SLOPE, FLAGS, "width_type"},
597
{"h", "Hz", 0, AV_OPT_TYPE_CONST, {.i64=HERTZ}, 0, 0, FLAGS, "width_type"},
598
{"q", "Q-Factor", 0, AV_OPT_TYPE_CONST, {.i64=QFACTOR}, 0, 0, FLAGS, "width_type"},
599
{"o", "octave", 0, AV_OPT_TYPE_CONST, {.i64=OCTAVE}, 0, 0, FLAGS, "width_type"},
600
{"s", "slope", 0, AV_OPT_TYPE_CONST, {.i64=SLOPE}, 0, 0, FLAGS, "width_type"},
601
{"width", "set filter-width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=707.1}, 0, 99999, FLAGS},
602
{"w", "set filter-width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=707.1}, 0, 99999, FLAGS},
606
DEFINE_BIQUAD_FILTER(allpass, "Apply a two-pole all-pass filter.");
607
#endif /* CONFIG_ALLPASS_FILTER */
608
#if CONFIG_BIQUAD_FILTER
609
static const AVOption biquad_options[] = {
610
{"a0", NULL, OFFSET(a0), AV_OPT_TYPE_DOUBLE, {.dbl=1}, INT16_MIN, INT16_MAX, FLAGS},
611
{"a1", NULL, OFFSET(a1), AV_OPT_TYPE_DOUBLE, {.dbl=1}, INT16_MIN, INT16_MAX, FLAGS},
612
{"a2", NULL, OFFSET(a2), AV_OPT_TYPE_DOUBLE, {.dbl=1}, INT16_MIN, INT16_MAX, FLAGS},
613
{"b0", NULL, OFFSET(b0), AV_OPT_TYPE_DOUBLE, {.dbl=1}, INT16_MIN, INT16_MAX, FLAGS},
614
{"b1", NULL, OFFSET(b1), AV_OPT_TYPE_DOUBLE, {.dbl=1}, INT16_MIN, INT16_MAX, FLAGS},
615
{"b2", NULL, OFFSET(b2), AV_OPT_TYPE_DOUBLE, {.dbl=1}, INT16_MIN, INT16_MAX, FLAGS},
619
DEFINE_BIQUAD_FILTER(biquad, "Apply a biquad IIR filter with the given coefficients.");
620
#endif /* CONFIG_BIQUAD_FILTER */