1 /*
2 * Copyright (c) 2016 Muhammad Faiz <mfcc64@gmail.com>
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include "libavutil/opt.h"
22 #include "libavutil/eval.h"
23 #include "libavutil/avassert.h"
24 #include "libavcodec/avfft.h"
25 #include "avfilter.h"
26 #include "internal.h"
27 #include "audio.h"
28
29 #define RDFT_BITS_MIN 4
30 #define RDFT_BITS_MAX 16
31
32 enum WindowFunc {
33 WFUNC_RECTANGULAR,
34 WFUNC_HANN,
35 WFUNC_HAMMING,
36 WFUNC_BLACKMAN,
37 WFUNC_NUTTALL3,
38 WFUNC_MNUTTALL3,
39 WFUNC_NUTTALL,
40 WFUNC_BNUTTALL,
41 WFUNC_BHARRIS,
42 WFUNC_TUKEY,
43 NB_WFUNC
44 };
45
46 enum Scale {
47 SCALE_LINLIN,
48 SCALE_LINLOG,
49 SCALE_LOGLIN,
50 SCALE_LOGLOG,
51 NB_SCALE
52 };
53
54 #define NB_GAIN_ENTRY_MAX 4096
55 typedef struct GainEntry {
56 double freq;
57 double gain;
58 } GainEntry;
59
60 typedef struct OverlapIndex {
61 int buf_idx;
62 int overlap_idx;
63 } OverlapIndex;
64
65 typedef struct FIREqualizerContext {
66 const AVClass *class;
67
68 RDFTContext *analysis_rdft;
69 RDFTContext *analysis_irdft;
70 RDFTContext *rdft;
71 RDFTContext *irdft;
72 FFTContext *fft_ctx;
73 RDFTContext *cepstrum_rdft;
74 RDFTContext *cepstrum_irdft;
75 int analysis_rdft_len;
76 int rdft_len;
77 int cepstrum_len;
78
79 float *analysis_buf;
80 float *dump_buf;
81 float *kernel_tmp_buf;
82 float *kernel_buf;
83 float *cepstrum_buf;
84 float *conv_buf;
85 OverlapIndex *conv_idx;
86 int fir_len;
87 int nsamples_max;
88 int64_t next_pts;
89 int frame_nsamples_max;
90 int remaining;
91
92 char *gain_cmd;
93 char *gain_entry_cmd;
94 const char *gain;
95 const char *gain_entry;
96 double delay;
97 double accuracy;
98 int wfunc;
99 int fixed;
100 int multi;
101 int zero_phase;
102 int scale;
103 char *dumpfile;
104 int dumpscale;
105 int fft2;
106 int min_phase;
107
108 int nb_gain_entry;
109 int gain_entry_err;
110 GainEntry gain_entry_tbl[NB_GAIN_ENTRY_MAX];
111 } FIREqualizerContext;
112
113 #define OFFSET(x) offsetof(FIREqualizerContext, x)
114 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
115 #define TFLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
116
117 static const AVOption firequalizer_options[] = {
118 { "gain", "set gain curve", OFFSET(gain), AV_OPT_TYPE_STRING, { .str = "gain_interpolate(f)" }, 0, 0, TFLAGS },
119 { "gain_entry", "set gain entry", OFFSET(gain_entry), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, TFLAGS },
120 { "delay", "set delay", OFFSET(delay), AV_OPT_TYPE_DOUBLE, { .dbl = 0.01 }, 0.0, 1e10, FLAGS },
121 { "accuracy", "set accuracy", OFFSET(accuracy), AV_OPT_TYPE_DOUBLE, { .dbl = 5.0 }, 0.0, 1e10, FLAGS },
122 { "wfunc", "set window function", OFFSET(wfunc), AV_OPT_TYPE_INT, { .i64 = WFUNC_HANN }, 0, NB_WFUNC-1, FLAGS, "wfunc" },
123 { "rectangular", "rectangular window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_RECTANGULAR }, 0, 0, FLAGS, "wfunc" },
124 { "hann", "hann window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_HANN }, 0, 0, FLAGS, "wfunc" },
125 { "hamming", "hamming window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_HAMMING }, 0, 0, FLAGS, "wfunc" },
126 { "blackman", "blackman window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BLACKMAN }, 0, 0, FLAGS, "wfunc" },
127 { "nuttall3", "3-term nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_NUTTALL3 }, 0, 0, FLAGS, "wfunc" },
128 { "mnuttall3", "minimum 3-term nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_MNUTTALL3 }, 0, 0, FLAGS, "wfunc" },
129 { "nuttall", "nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_NUTTALL }, 0, 0, FLAGS, "wfunc" },
130 { "bnuttall", "blackman-nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BNUTTALL }, 0, 0, FLAGS, "wfunc" },
131 { "bharris", "blackman-harris window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BHARRIS }, 0, 0, FLAGS, "wfunc" },
132 { "tukey", "tukey window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_TUKEY }, 0, 0, FLAGS, "wfunc" },
133 { "fixed", "set fixed frame samples", OFFSET(fixed), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
134 { "multi", "set multi channels mode", OFFSET(multi), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
135 { "zero_phase", "set zero phase mode", OFFSET(zero_phase), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
136 { "scale", "set gain scale", OFFSET(scale), AV_OPT_TYPE_INT, { .i64 = SCALE_LINLOG }, 0, NB_SCALE-1, FLAGS, "scale" },
137 { "linlin", "linear-freq linear-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LINLIN }, 0, 0, FLAGS, "scale" },
138 { "linlog", "linear-freq logarithmic-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LINLOG }, 0, 0, FLAGS, "scale" },
139 { "loglin", "logarithmic-freq linear-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LOGLIN }, 0, 0, FLAGS, "scale" },
140 { "loglog", "logarithmic-freq logarithmic-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LOGLOG }, 0, 0, FLAGS, "scale" },
141 { "dumpfile", "set dump file", OFFSET(dumpfile), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, FLAGS },
142 { "dumpscale", "set dump scale", OFFSET(dumpscale), AV_OPT_TYPE_INT, { .i64 = SCALE_LINLOG }, 0, NB_SCALE-1, FLAGS, "scale" },
143 { "fft2", "set 2-channels fft", OFFSET(fft2), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
144 { "min_phase", "set minimum phase mode", OFFSET(min_phase), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
145 { NULL }
146 };
147
148 AVFILTER_DEFINE_CLASS(firequalizer);
149
common_uninit(FIREqualizerContext * s)150 static void common_uninit(FIREqualizerContext *s)
151 {
152 av_rdft_end(s->analysis_rdft);
153 av_rdft_end(s->analysis_irdft);
154 av_rdft_end(s->rdft);
155 av_rdft_end(s->irdft);
156 av_fft_end(s->fft_ctx);
157 av_rdft_end(s->cepstrum_rdft);
158 av_rdft_end(s->cepstrum_irdft);
159 s->analysis_rdft = s->analysis_irdft = s->rdft = s->irdft = NULL;
160 s->fft_ctx = NULL;
161 s->cepstrum_rdft = NULL;
162 s->cepstrum_irdft = NULL;
163
164 av_freep(&s->analysis_buf);
165 av_freep(&s->dump_buf);
166 av_freep(&s->kernel_tmp_buf);
167 av_freep(&s->kernel_buf);
168 av_freep(&s->cepstrum_buf);
169 av_freep(&s->conv_buf);
170 av_freep(&s->conv_idx);
171 }
172
uninit(AVFilterContext * ctx)173 static av_cold void uninit(AVFilterContext *ctx)
174 {
175 FIREqualizerContext *s = ctx->priv;
176
177 common_uninit(s);
178 av_freep(&s->gain_cmd);
179 av_freep(&s->gain_entry_cmd);
180 }
181
query_formats(AVFilterContext * ctx)182 static int query_formats(AVFilterContext *ctx)
183 {
184 AVFilterChannelLayouts *layouts;
185 AVFilterFormats *formats;
186 static const enum AVSampleFormat sample_fmts[] = {
187 AV_SAMPLE_FMT_FLTP,
188 AV_SAMPLE_FMT_NONE
189 };
190 int ret;
191
192 layouts = ff_all_channel_counts();
193 if (!layouts)
194 return AVERROR(ENOMEM);
195 ret = ff_set_common_channel_layouts(ctx, layouts);
196 if (ret < 0)
197 return ret;
198
199 formats = ff_make_format_list(sample_fmts);
200 if (!formats)
201 return AVERROR(ENOMEM);
202 ret = ff_set_common_formats(ctx, formats);
203 if (ret < 0)
204 return ret;
205
206 formats = ff_all_samplerates();
207 if (!formats)
208 return AVERROR(ENOMEM);
209 return ff_set_common_samplerates(ctx, formats);
210 }
211
fast_convolute(FIREqualizerContext * av_restrict s,const float * av_restrict kernel_buf,float * av_restrict conv_buf,OverlapIndex * av_restrict idx,float * av_restrict data,int nsamples)212 static void fast_convolute(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf, float *av_restrict conv_buf,
213 OverlapIndex *av_restrict idx, float *av_restrict data, int nsamples)
214 {
215 if (nsamples <= s->nsamples_max) {
216 float *buf = conv_buf + idx->buf_idx * s->rdft_len;
217 float *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
218 int center = s->fir_len/2;
219 int k;
220
221 memset(buf, 0, center * sizeof(*data));
222 memcpy(buf + center, data, nsamples * sizeof(*data));
223 memset(buf + center + nsamples, 0, (s->rdft_len - nsamples - center) * sizeof(*data));
224 av_rdft_calc(s->rdft, buf);
225
226 buf[0] *= kernel_buf[0];
227 buf[1] *= kernel_buf[s->rdft_len/2];
228 for (k = 1; k < s->rdft_len/2; k++) {
229 buf[2*k] *= kernel_buf[k];
230 buf[2*k+1] *= kernel_buf[k];
231 }
232
233 av_rdft_calc(s->irdft, buf);
234 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++)
235 buf[k] += obuf[k];
236 memcpy(data, buf, nsamples * sizeof(*data));
237 idx->buf_idx = !idx->buf_idx;
238 idx->overlap_idx = nsamples;
239 } else {
240 while (nsamples > s->nsamples_max * 2) {
241 fast_convolute(s, kernel_buf, conv_buf, idx, data, s->nsamples_max);
242 data += s->nsamples_max;
243 nsamples -= s->nsamples_max;
244 }
245 fast_convolute(s, kernel_buf, conv_buf, idx, data, nsamples/2);
246 fast_convolute(s, kernel_buf, conv_buf, idx, data + nsamples/2, nsamples - nsamples/2);
247 }
248 }
249
fast_convolute_nonlinear(FIREqualizerContext * av_restrict s,const float * av_restrict kernel_buf,float * av_restrict conv_buf,OverlapIndex * av_restrict idx,float * av_restrict data,int nsamples)250 static void fast_convolute_nonlinear(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf,
251 float *av_restrict conv_buf, OverlapIndex *av_restrict idx,
252 float *av_restrict data, int nsamples)
253 {
254 if (nsamples <= s->nsamples_max) {
255 float *buf = conv_buf + idx->buf_idx * s->rdft_len;
256 float *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
257 int k;
258
259 memcpy(buf, data, nsamples * sizeof(*data));
260 memset(buf + nsamples, 0, (s->rdft_len - nsamples) * sizeof(*data));
261 av_rdft_calc(s->rdft, buf);
262
263 buf[0] *= kernel_buf[0];
264 buf[1] *= kernel_buf[1];
265 for (k = 2; k < s->rdft_len; k += 2) {
266 float re, im;
267 re = buf[k] * kernel_buf[k] - buf[k+1] * kernel_buf[k+1];
268 im = buf[k] * kernel_buf[k+1] + buf[k+1] * kernel_buf[k];
269 buf[k] = re;
270 buf[k+1] = im;
271 }
272
273 av_rdft_calc(s->irdft, buf);
274 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++)
275 buf[k] += obuf[k];
276 memcpy(data, buf, nsamples * sizeof(*data));
277 idx->buf_idx = !idx->buf_idx;
278 idx->overlap_idx = nsamples;
279 } else {
280 while (nsamples > s->nsamples_max * 2) {
281 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data, s->nsamples_max);
282 data += s->nsamples_max;
283 nsamples -= s->nsamples_max;
284 }
285 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data, nsamples/2);
286 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data + nsamples/2, nsamples - nsamples/2);
287 }
288 }
289
fast_convolute2(FIREqualizerContext * av_restrict s,const float * av_restrict kernel_buf,FFTComplex * av_restrict conv_buf,OverlapIndex * av_restrict idx,float * av_restrict data0,float * av_restrict data1,int nsamples)290 static void fast_convolute2(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf, FFTComplex *av_restrict conv_buf,
291 OverlapIndex *av_restrict idx, float *av_restrict data0, float *av_restrict data1, int nsamples)
292 {
293 if (nsamples <= s->nsamples_max) {
294 FFTComplex *buf = conv_buf + idx->buf_idx * s->rdft_len;
295 FFTComplex *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
296 int center = s->fir_len/2;
297 int k;
298 float tmp;
299
300 memset(buf, 0, center * sizeof(*buf));
301 for (k = 0; k < nsamples; k++) {
302 buf[center+k].re = data0[k];
303 buf[center+k].im = data1[k];
304 }
305 memset(buf + center + nsamples, 0, (s->rdft_len - nsamples - center) * sizeof(*buf));
306 av_fft_permute(s->fft_ctx, buf);
307 av_fft_calc(s->fft_ctx, buf);
308
309 /* swap re <-> im, do backward fft using forward fft_ctx */
310 /* normalize with 0.5f */
311 tmp = buf[0].re;
312 buf[0].re = 0.5f * kernel_buf[0] * buf[0].im;
313 buf[0].im = 0.5f * kernel_buf[0] * tmp;
314 for (k = 1; k < s->rdft_len/2; k++) {
315 int m = s->rdft_len - k;
316 tmp = buf[k].re;
317 buf[k].re = 0.5f * kernel_buf[k] * buf[k].im;
318 buf[k].im = 0.5f * kernel_buf[k] * tmp;
319 tmp = buf[m].re;
320 buf[m].re = 0.5f * kernel_buf[k] * buf[m].im;
321 buf[m].im = 0.5f * kernel_buf[k] * tmp;
322 }
323 tmp = buf[k].re;
324 buf[k].re = 0.5f * kernel_buf[k] * buf[k].im;
325 buf[k].im = 0.5f * kernel_buf[k] * tmp;
326
327 av_fft_permute(s->fft_ctx, buf);
328 av_fft_calc(s->fft_ctx, buf);
329
330 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++) {
331 buf[k].re += obuf[k].re;
332 buf[k].im += obuf[k].im;
333 }
334
335 /* swapped re <-> im */
336 for (k = 0; k < nsamples; k++) {
337 data0[k] = buf[k].im;
338 data1[k] = buf[k].re;
339 }
340 idx->buf_idx = !idx->buf_idx;
341 idx->overlap_idx = nsamples;
342 } else {
343 while (nsamples > s->nsamples_max * 2) {
344 fast_convolute2(s, kernel_buf, conv_buf, idx, data0, data1, s->nsamples_max);
345 data0 += s->nsamples_max;
346 data1 += s->nsamples_max;
347 nsamples -= s->nsamples_max;
348 }
349 fast_convolute2(s, kernel_buf, conv_buf, idx, data0, data1, nsamples/2);
350 fast_convolute2(s, kernel_buf, conv_buf, idx, data0 + nsamples/2, data1 + nsamples/2, nsamples - nsamples/2);
351 }
352 }
353
dump_fir(AVFilterContext * ctx,FILE * fp,int ch)354 static void dump_fir(AVFilterContext *ctx, FILE *fp, int ch)
355 {
356 FIREqualizerContext *s = ctx->priv;
357 int rate = ctx->inputs[0]->sample_rate;
358 int xlog = s->dumpscale == SCALE_LOGLIN || s->dumpscale == SCALE_LOGLOG;
359 int ylog = s->dumpscale == SCALE_LINLOG || s->dumpscale == SCALE_LOGLOG;
360 int x;
361 int center = s->fir_len / 2;
362 double delay = s->zero_phase ? 0.0 : (double) center / rate;
363 double vx, ya, yb;
364
365 if (!s->min_phase) {
366 s->analysis_buf[0] *= s->rdft_len/2;
367 for (x = 1; x <= center; x++) {
368 s->analysis_buf[x] *= s->rdft_len/2;
369 s->analysis_buf[s->analysis_rdft_len - x] *= s->rdft_len/2;
370 }
371 } else {
372 for (x = 0; x < s->fir_len; x++)
373 s->analysis_buf[x] *= s->rdft_len/2;
374 }
375
376 if (ch)
377 fprintf(fp, "\n\n");
378
379 fprintf(fp, "# time[%d] (time amplitude)\n", ch);
380
381 if (!s->min_phase) {
382 for (x = center; x > 0; x--)
383 fprintf(fp, "%15.10f %15.10f\n", delay - (double) x / rate, (double) s->analysis_buf[s->analysis_rdft_len - x]);
384
385 for (x = 0; x <= center; x++)
386 fprintf(fp, "%15.10f %15.10f\n", delay + (double)x / rate , (double) s->analysis_buf[x]);
387 } else {
388 for (x = 0; x < s->fir_len; x++)
389 fprintf(fp, "%15.10f %15.10f\n", (double)x / rate, (double) s->analysis_buf[x]);
390 }
391
392 av_rdft_calc(s->analysis_rdft, s->analysis_buf);
393
394 fprintf(fp, "\n\n# freq[%d] (frequency desired_gain actual_gain)\n", ch);
395
396 for (x = 0; x <= s->analysis_rdft_len/2; x++) {
397 int i = (x == s->analysis_rdft_len/2) ? 1 : 2 * x;
398 vx = (double)x * rate / s->analysis_rdft_len;
399 if (xlog)
400 vx = log2(0.05*vx);
401 ya = s->dump_buf[i];
402 yb = s->min_phase && (i > 1) ? hypotf(s->analysis_buf[i], s->analysis_buf[i+1]) : s->analysis_buf[i];
403 if (s->min_phase)
404 yb = fabs(yb);
405 if (ylog) {
406 ya = 20.0 * log10(fabs(ya));
407 yb = 20.0 * log10(fabs(yb));
408 }
409 fprintf(fp, "%17.10f %17.10f %17.10f\n", vx, ya, yb);
410 }
411 }
412
entry_func(void * p,double freq,double gain)413 static double entry_func(void *p, double freq, double gain)
414 {
415 AVFilterContext *ctx = p;
416 FIREqualizerContext *s = ctx->priv;
417
418 if (s->nb_gain_entry >= NB_GAIN_ENTRY_MAX) {
419 av_log(ctx, AV_LOG_ERROR, "entry table overflow.\n");
420 s->gain_entry_err = AVERROR(EINVAL);
421 return 0;
422 }
423
424 if (isnan(freq)) {
425 av_log(ctx, AV_LOG_ERROR, "nan frequency (%g, %g).\n", freq, gain);
426 s->gain_entry_err = AVERROR(EINVAL);
427 return 0;
428 }
429
430 if (s->nb_gain_entry > 0 && freq <= s->gain_entry_tbl[s->nb_gain_entry - 1].freq) {
431 av_log(ctx, AV_LOG_ERROR, "unsorted frequency (%g, %g).\n", freq, gain);
432 s->gain_entry_err = AVERROR(EINVAL);
433 return 0;
434 }
435
436 s->gain_entry_tbl[s->nb_gain_entry].freq = freq;
437 s->gain_entry_tbl[s->nb_gain_entry].gain = gain;
438 s->nb_gain_entry++;
439 return 0;
440 }
441
gain_entry_compare(const void * key,const void * memb)442 static int gain_entry_compare(const void *key, const void *memb)
443 {
444 const double *freq = key;
445 const GainEntry *entry = memb;
446
447 if (*freq < entry[0].freq)
448 return -1;
449 if (*freq > entry[1].freq)
450 return 1;
451 return 0;
452 }
453
gain_interpolate_func(void * p,double freq)454 static double gain_interpolate_func(void *p, double freq)
455 {
456 AVFilterContext *ctx = p;
457 FIREqualizerContext *s = ctx->priv;
458 GainEntry *res;
459 double d0, d1, d;
460
461 if (isnan(freq))
462 return freq;
463
464 if (!s->nb_gain_entry)
465 return 0;
466
467 if (freq <= s->gain_entry_tbl[0].freq)
468 return s->gain_entry_tbl[0].gain;
469
470 if (freq >= s->gain_entry_tbl[s->nb_gain_entry-1].freq)
471 return s->gain_entry_tbl[s->nb_gain_entry-1].gain;
472
473 res = bsearch(&freq, &s->gain_entry_tbl, s->nb_gain_entry - 1, sizeof(*res), gain_entry_compare);
474 av_assert0(res);
475
476 d = res[1].freq - res[0].freq;
477 d0 = freq - res[0].freq;
478 d1 = res[1].freq - freq;
479
480 if (d0 && d1)
481 return (d0 * res[1].gain + d1 * res[0].gain) / d;
482
483 if (d0)
484 return res[1].gain;
485
486 return res[0].gain;
487 }
488
cubic_interpolate_func(void * p,double freq)489 static double cubic_interpolate_func(void *p, double freq)
490 {
491 AVFilterContext *ctx = p;
492 FIREqualizerContext *s = ctx->priv;
493 GainEntry *res;
494 double x, x2, x3;
495 double a, b, c, d;
496 double m0, m1, m2, msum, unit;
497
498 if (!s->nb_gain_entry)
499 return 0;
500
501 if (freq <= s->gain_entry_tbl[0].freq)
502 return s->gain_entry_tbl[0].gain;
503
504 if (freq >= s->gain_entry_tbl[s->nb_gain_entry-1].freq)
505 return s->gain_entry_tbl[s->nb_gain_entry-1].gain;
506
507 res = bsearch(&freq, &s->gain_entry_tbl, s->nb_gain_entry - 1, sizeof(*res), gain_entry_compare);
508 av_assert0(res);
509
510 unit = res[1].freq - res[0].freq;
511 m0 = res != s->gain_entry_tbl ?
512 unit * (res[0].gain - res[-1].gain) / (res[0].freq - res[-1].freq) : 0;
513 m1 = res[1].gain - res[0].gain;
514 m2 = res != s->gain_entry_tbl + s->nb_gain_entry - 2 ?
515 unit * (res[2].gain - res[1].gain) / (res[2].freq - res[1].freq) : 0;
516
517 msum = fabs(m0) + fabs(m1);
518 m0 = msum > 0 ? (fabs(m0) * m1 + fabs(m1) * m0) / msum : 0;
519 msum = fabs(m1) + fabs(m2);
520 m1 = msum > 0 ? (fabs(m1) * m2 + fabs(m2) * m1) / msum : 0;
521
522 d = res[0].gain;
523 c = m0;
524 b = 3 * res[1].gain - m1 - 2 * c - 3 * d;
525 a = res[1].gain - b - c - d;
526
527 x = (freq - res[0].freq) / unit;
528 x2 = x * x;
529 x3 = x2 * x;
530
531 return a * x3 + b * x2 + c * x + d;
532 }
533
534 static const char *const var_names[] = {
535 "f",
536 "sr",
537 "ch",
538 "chid",
539 "chs",
540 "chlayout",
541 NULL
542 };
543
544 enum VarOffset {
545 VAR_F,
546 VAR_SR,
547 VAR_CH,
548 VAR_CHID,
549 VAR_CHS,
550 VAR_CHLAYOUT,
551 VAR_NB
552 };
553
generate_min_phase_kernel(FIREqualizerContext * s,float * rdft_buf)554 static void generate_min_phase_kernel(FIREqualizerContext *s, float *rdft_buf)
555 {
556 int k, cepstrum_len = s->cepstrum_len, rdft_len = s->rdft_len;
557 double norm = 2.0 / cepstrum_len;
558 double minval = 1e-7 / rdft_len;
559
560 memset(s->cepstrum_buf, 0, cepstrum_len * sizeof(*s->cepstrum_buf));
561 memcpy(s->cepstrum_buf, rdft_buf, rdft_len/2 * sizeof(*rdft_buf));
562 memcpy(s->cepstrum_buf + cepstrum_len - rdft_len/2, rdft_buf + rdft_len/2, rdft_len/2 * sizeof(*rdft_buf));
563
564 av_rdft_calc(s->cepstrum_rdft, s->cepstrum_buf);
565
566 s->cepstrum_buf[0] = log(FFMAX(s->cepstrum_buf[0], minval));
567 s->cepstrum_buf[1] = log(FFMAX(s->cepstrum_buf[1], minval));
568
569 for (k = 2; k < cepstrum_len; k += 2) {
570 s->cepstrum_buf[k] = log(FFMAX(s->cepstrum_buf[k], minval));
571 s->cepstrum_buf[k+1] = 0;
572 }
573
574 av_rdft_calc(s->cepstrum_irdft, s->cepstrum_buf);
575
576 memset(s->cepstrum_buf + cepstrum_len/2 + 1, 0, (cepstrum_len/2 - 1) * sizeof(*s->cepstrum_buf));
577 for (k = 1; k < cepstrum_len/2; k++)
578 s->cepstrum_buf[k] *= 2;
579
580 av_rdft_calc(s->cepstrum_rdft, s->cepstrum_buf);
581
582 s->cepstrum_buf[0] = exp(s->cepstrum_buf[0] * norm) * norm;
583 s->cepstrum_buf[1] = exp(s->cepstrum_buf[1] * norm) * norm;
584 for (k = 2; k < cepstrum_len; k += 2) {
585 double mag = exp(s->cepstrum_buf[k] * norm) * norm;
586 double ph = s->cepstrum_buf[k+1] * norm;
587 s->cepstrum_buf[k] = mag * cos(ph);
588 s->cepstrum_buf[k+1] = mag * sin(ph);
589 }
590
591 av_rdft_calc(s->cepstrum_irdft, s->cepstrum_buf);
592 memset(rdft_buf, 0, s->rdft_len * sizeof(*rdft_buf));
593 memcpy(rdft_buf, s->cepstrum_buf, s->fir_len * sizeof(*rdft_buf));
594
595 if (s->dumpfile) {
596 memset(s->analysis_buf, 0, s->analysis_rdft_len * sizeof(*s->analysis_buf));
597 memcpy(s->analysis_buf, s->cepstrum_buf, s->fir_len * sizeof(*s->analysis_buf));
598 }
599
600 }
601
generate_kernel(AVFilterContext * ctx,const char * gain,const char * gain_entry)602 static int generate_kernel(AVFilterContext *ctx, const char *gain, const char *gain_entry)
603 {
604 FIREqualizerContext *s = ctx->priv;
605 AVFilterLink *inlink = ctx->inputs[0];
606 const char *gain_entry_func_names[] = { "entry", NULL };
607 const char *gain_func_names[] = { "gain_interpolate", "cubic_interpolate", NULL };
608 double (*gain_entry_funcs[])(void *, double, double) = { entry_func, NULL };
609 double (*gain_funcs[])(void *, double) = { gain_interpolate_func, cubic_interpolate_func, NULL };
610 double vars[VAR_NB];
611 AVExpr *gain_expr;
612 int ret, k, center, ch;
613 int xlog = s->scale == SCALE_LOGLIN || s->scale == SCALE_LOGLOG;
614 int ylog = s->scale == SCALE_LINLOG || s->scale == SCALE_LOGLOG;
615 FILE *dump_fp = NULL;
616
617 s->nb_gain_entry = 0;
618 s->gain_entry_err = 0;
619 if (gain_entry) {
620 double result = 0.0;
621 ret = av_expr_parse_and_eval(&result, gain_entry, NULL, NULL, NULL, NULL,
622 gain_entry_func_names, gain_entry_funcs, ctx, 0, ctx);
623 if (ret < 0)
624 return ret;
625 if (s->gain_entry_err < 0)
626 return s->gain_entry_err;
627 }
628
629 av_log(ctx, AV_LOG_DEBUG, "nb_gain_entry = %d.\n", s->nb_gain_entry);
630
631 ret = av_expr_parse(&gain_expr, gain, var_names,
632 gain_func_names, gain_funcs, NULL, NULL, 0, ctx);
633 if (ret < 0)
634 return ret;
635
636 if (s->dumpfile && (!s->dump_buf || !s->analysis_rdft || !(dump_fp = fopen(s->dumpfile, "w"))))
637 av_log(ctx, AV_LOG_WARNING, "dumping failed.\n");
638
639 vars[VAR_CHS] = inlink->channels;
640 vars[VAR_CHLAYOUT] = inlink->channel_layout;
641 vars[VAR_SR] = inlink->sample_rate;
642 for (ch = 0; ch < inlink->channels; ch++) {
643 float *rdft_buf = s->kernel_tmp_buf + ch * s->rdft_len;
644 double result;
645 vars[VAR_CH] = ch;
646 vars[VAR_CHID] = av_channel_layout_extract_channel(inlink->channel_layout, ch);
647 vars[VAR_F] = 0.0;
648 if (xlog)
649 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
650 result = av_expr_eval(gain_expr, vars, ctx);
651 s->analysis_buf[0] = ylog ? pow(10.0, 0.05 * result) : result;
652
653 vars[VAR_F] = 0.5 * inlink->sample_rate;
654 if (xlog)
655 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
656 result = av_expr_eval(gain_expr, vars, ctx);
657 s->analysis_buf[1] = ylog ? pow(10.0, 0.05 * result) : result;
658
659 for (k = 1; k < s->analysis_rdft_len/2; k++) {
660 vars[VAR_F] = k * ((double)inlink->sample_rate /(double)s->analysis_rdft_len);
661 if (xlog)
662 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
663 result = av_expr_eval(gain_expr, vars, ctx);
664 s->analysis_buf[2*k] = ylog ? pow(10.0, 0.05 * result) : s->min_phase ? fabs(result) : result;
665 s->analysis_buf[2*k+1] = 0.0;
666 }
667
668 if (s->dump_buf)
669 memcpy(s->dump_buf, s->analysis_buf, s->analysis_rdft_len * sizeof(*s->analysis_buf));
670
671 av_rdft_calc(s->analysis_irdft, s->analysis_buf);
672 center = s->fir_len / 2;
673
674 for (k = 0; k <= center; k++) {
675 double u = k * (M_PI/center);
676 double win;
677 switch (s->wfunc) {
678 case WFUNC_RECTANGULAR:
679 win = 1.0;
680 break;
681 case WFUNC_HANN:
682 win = 0.5 + 0.5 * cos(u);
683 break;
684 case WFUNC_HAMMING:
685 win = 0.53836 + 0.46164 * cos(u);
686 break;
687 case WFUNC_BLACKMAN:
688 win = 0.42 + 0.5 * cos(u) + 0.08 * cos(2*u);
689 break;
690 case WFUNC_NUTTALL3:
691 win = 0.40897 + 0.5 * cos(u) + 0.09103 * cos(2*u);
692 break;
693 case WFUNC_MNUTTALL3:
694 win = 0.4243801 + 0.4973406 * cos(u) + 0.0782793 * cos(2*u);
695 break;
696 case WFUNC_NUTTALL:
697 win = 0.355768 + 0.487396 * cos(u) + 0.144232 * cos(2*u) + 0.012604 * cos(3*u);
698 break;
699 case WFUNC_BNUTTALL:
700 win = 0.3635819 + 0.4891775 * cos(u) + 0.1365995 * cos(2*u) + 0.0106411 * cos(3*u);
701 break;
702 case WFUNC_BHARRIS:
703 win = 0.35875 + 0.48829 * cos(u) + 0.14128 * cos(2*u) + 0.01168 * cos(3*u);
704 break;
705 case WFUNC_TUKEY:
706 win = (u <= 0.5 * M_PI) ? 1.0 : (0.5 + 0.5 * cos(2*u - M_PI));
707 break;
708 default:
709 av_assert0(0);
710 }
711 s->analysis_buf[k] *= (2.0/s->analysis_rdft_len) * (2.0/s->rdft_len) * win;
712 if (k)
713 s->analysis_buf[s->analysis_rdft_len - k] = s->analysis_buf[k];
714 }
715
716 memset(s->analysis_buf + center + 1, 0, (s->analysis_rdft_len - s->fir_len) * sizeof(*s->analysis_buf));
717 memcpy(rdft_buf, s->analysis_buf, s->rdft_len/2 * sizeof(*s->analysis_buf));
718 memcpy(rdft_buf + s->rdft_len/2, s->analysis_buf + s->analysis_rdft_len - s->rdft_len/2, s->rdft_len/2 * sizeof(*s->analysis_buf));
719 if (s->min_phase)
720 generate_min_phase_kernel(s, rdft_buf);
721 av_rdft_calc(s->rdft, rdft_buf);
722
723 for (k = 0; k < s->rdft_len; k++) {
724 if (isnan(rdft_buf[k]) || isinf(rdft_buf[k])) {
725 av_log(ctx, AV_LOG_ERROR, "filter kernel contains nan or infinity.\n");
726 av_expr_free(gain_expr);
727 if (dump_fp)
728 fclose(dump_fp);
729 return AVERROR(EINVAL);
730 }
731 }
732
733 if (!s->min_phase) {
734 rdft_buf[s->rdft_len-1] = rdft_buf[1];
735 for (k = 0; k < s->rdft_len/2; k++)
736 rdft_buf[k] = rdft_buf[2*k];
737 rdft_buf[s->rdft_len/2] = rdft_buf[s->rdft_len-1];
738 }
739
740 if (dump_fp)
741 dump_fir(ctx, dump_fp, ch);
742
743 if (!s->multi)
744 break;
745 }
746
747 memcpy(s->kernel_buf, s->kernel_tmp_buf, (s->multi ? inlink->channels : 1) * s->rdft_len * sizeof(*s->kernel_buf));
748 av_expr_free(gain_expr);
749 if (dump_fp)
750 fclose(dump_fp);
751 return 0;
752 }
753
754 #define SELECT_GAIN(s) (s->gain_cmd ? s->gain_cmd : s->gain)
755 #define SELECT_GAIN_ENTRY(s) (s->gain_entry_cmd ? s->gain_entry_cmd : s->gain_entry)
756
config_input(AVFilterLink * inlink)757 static int config_input(AVFilterLink *inlink)
758 {
759 AVFilterContext *ctx = inlink->dst;
760 FIREqualizerContext *s = ctx->priv;
761 int rdft_bits;
762
763 common_uninit(s);
764
765 s->next_pts = 0;
766 s->frame_nsamples_max = 0;
767
768 s->fir_len = FFMAX(2 * (int)(inlink->sample_rate * s->delay) + 1, 3);
769 s->remaining = s->fir_len - 1;
770
771 for (rdft_bits = RDFT_BITS_MIN; rdft_bits <= RDFT_BITS_MAX; rdft_bits++) {
772 s->rdft_len = 1 << rdft_bits;
773 s->nsamples_max = s->rdft_len - s->fir_len + 1;
774 if (s->nsamples_max * 2 >= s->fir_len)
775 break;
776 }
777
778 if (rdft_bits > RDFT_BITS_MAX) {
779 av_log(ctx, AV_LOG_ERROR, "too large delay, please decrease it.\n");
780 return AVERROR(EINVAL);
781 }
782
783 if (!(s->rdft = av_rdft_init(rdft_bits, DFT_R2C)) || !(s->irdft = av_rdft_init(rdft_bits, IDFT_C2R)))
784 return AVERROR(ENOMEM);
785
786 if (s->fft2 && !s->multi && inlink->channels > 1 && !(s->fft_ctx = av_fft_init(rdft_bits, 0)))
787 return AVERROR(ENOMEM);
788
789 if (s->min_phase) {
790 int cepstrum_bits = rdft_bits + 2;
791 if (cepstrum_bits > RDFT_BITS_MAX) {
792 av_log(ctx, AV_LOG_ERROR, "too large delay, please decrease it.\n");
793 return AVERROR(EINVAL);
794 }
795
796 cepstrum_bits = FFMIN(RDFT_BITS_MAX, cepstrum_bits + 1);
797 s->cepstrum_rdft = av_rdft_init(cepstrum_bits, DFT_R2C);
798 s->cepstrum_irdft = av_rdft_init(cepstrum_bits, IDFT_C2R);
799 if (!s->cepstrum_rdft || !s->cepstrum_irdft)
800 return AVERROR(ENOMEM);
801
802 s->cepstrum_len = 1 << cepstrum_bits;
803 s->cepstrum_buf = av_malloc_array(s->cepstrum_len, sizeof(*s->cepstrum_buf));
804 if (!s->cepstrum_buf)
805 return AVERROR(ENOMEM);
806 }
807
808 for ( ; rdft_bits <= RDFT_BITS_MAX; rdft_bits++) {
809 s->analysis_rdft_len = 1 << rdft_bits;
810 if (inlink->sample_rate <= s->accuracy * s->analysis_rdft_len)
811 break;
812 }
813
814 if (rdft_bits > RDFT_BITS_MAX) {
815 av_log(ctx, AV_LOG_ERROR, "too small accuracy, please increase it.\n");
816 return AVERROR(EINVAL);
817 }
818
819 if (!(s->analysis_irdft = av_rdft_init(rdft_bits, IDFT_C2R)))
820 return AVERROR(ENOMEM);
821
822 if (s->dumpfile) {
823 s->analysis_rdft = av_rdft_init(rdft_bits, DFT_R2C);
824 s->dump_buf = av_malloc_array(s->analysis_rdft_len, sizeof(*s->dump_buf));
825 }
826
827 s->analysis_buf = av_malloc_array(s->analysis_rdft_len, sizeof(*s->analysis_buf));
828 s->kernel_tmp_buf = av_malloc_array(s->rdft_len * (s->multi ? inlink->channels : 1), sizeof(*s->kernel_tmp_buf));
829 s->kernel_buf = av_malloc_array(s->rdft_len * (s->multi ? inlink->channels : 1), sizeof(*s->kernel_buf));
830 s->conv_buf = av_calloc(2 * s->rdft_len * inlink->channels, sizeof(*s->conv_buf));
831 s->conv_idx = av_calloc(inlink->channels, sizeof(*s->conv_idx));
832 if (!s->analysis_buf || !s->kernel_tmp_buf || !s->kernel_buf || !s->conv_buf || !s->conv_idx)
833 return AVERROR(ENOMEM);
834
835 av_log(ctx, AV_LOG_DEBUG, "sample_rate = %d, channels = %d, analysis_rdft_len = %d, rdft_len = %d, fir_len = %d, nsamples_max = %d.\n",
836 inlink->sample_rate, inlink->channels, s->analysis_rdft_len, s->rdft_len, s->fir_len, s->nsamples_max);
837
838 if (s->fixed)
839 inlink->min_samples = inlink->max_samples = inlink->partial_buf_size = s->nsamples_max;
840
841 return generate_kernel(ctx, SELECT_GAIN(s), SELECT_GAIN_ENTRY(s));
842 }
843
filter_frame(AVFilterLink * inlink,AVFrame * frame)844 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
845 {
846 AVFilterContext *ctx = inlink->dst;
847 FIREqualizerContext *s = ctx->priv;
848 int ch;
849
850 if (!s->min_phase) {
851 for (ch = 0; ch + 1 < inlink->channels && s->fft_ctx; ch += 2) {
852 fast_convolute2(s, s->kernel_buf, (FFTComplex *)(s->conv_buf + 2 * ch * s->rdft_len),
853 s->conv_idx + ch, (float *) frame->extended_data[ch],
854 (float *) frame->extended_data[ch+1], frame->nb_samples);
855 }
856
857 for ( ; ch < inlink->channels; ch++) {
858 fast_convolute(s, s->kernel_buf + (s->multi ? ch * s->rdft_len : 0),
859 s->conv_buf + 2 * ch * s->rdft_len, s->conv_idx + ch,
860 (float *) frame->extended_data[ch], frame->nb_samples);
861 }
862 } else {
863 for (ch = 0; ch < inlink->channels; ch++) {
864 fast_convolute_nonlinear(s, s->kernel_buf + (s->multi ? ch * s->rdft_len : 0),
865 s->conv_buf + 2 * ch * s->rdft_len, s->conv_idx + ch,
866 (float *) frame->extended_data[ch], frame->nb_samples);
867 }
868 }
869
870 s->next_pts = AV_NOPTS_VALUE;
871 if (frame->pts != AV_NOPTS_VALUE) {
872 s->next_pts = frame->pts + av_rescale_q(frame->nb_samples, av_make_q(1, inlink->sample_rate), inlink->time_base);
873 if (s->zero_phase && !s->min_phase)
874 frame->pts -= av_rescale_q(s->fir_len/2, av_make_q(1, inlink->sample_rate), inlink->time_base);
875 }
876 s->frame_nsamples_max = FFMAX(s->frame_nsamples_max, frame->nb_samples);
877 return ff_filter_frame(ctx->outputs[0], frame);
878 }
879
request_frame(AVFilterLink * outlink)880 static int request_frame(AVFilterLink *outlink)
881 {
882 AVFilterContext *ctx = outlink->src;
883 FIREqualizerContext *s= ctx->priv;
884 int ret;
885
886 ret = ff_request_frame(ctx->inputs[0]);
887 if (ret == AVERROR_EOF && s->remaining > 0 && s->frame_nsamples_max > 0) {
888 AVFrame *frame = ff_get_audio_buffer(outlink, FFMIN(s->remaining, s->frame_nsamples_max));
889
890 if (!frame)
891 return AVERROR(ENOMEM);
892
893 av_samples_set_silence(frame->extended_data, 0, frame->nb_samples, outlink->channels, frame->format);
894 frame->pts = s->next_pts;
895 s->remaining -= frame->nb_samples;
896 ret = filter_frame(ctx->inputs[0], frame);
897 }
898
899 return ret;
900 }
901
process_command(AVFilterContext * ctx,const char * cmd,const char * args,char * res,int res_len,int flags)902 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
903 char *res, int res_len, int flags)
904 {
905 FIREqualizerContext *s = ctx->priv;
906 int ret = AVERROR(ENOSYS);
907
908 if (!strcmp(cmd, "gain")) {
909 char *gain_cmd;
910
911 if (SELECT_GAIN(s) && !strcmp(SELECT_GAIN(s), args)) {
912 av_log(ctx, AV_LOG_DEBUG, "equal gain, do not rebuild.\n");
913 return 0;
914 }
915
916 gain_cmd = av_strdup(args);
917 if (!gain_cmd)
918 return AVERROR(ENOMEM);
919
920 ret = generate_kernel(ctx, gain_cmd, SELECT_GAIN_ENTRY(s));
921 if (ret >= 0) {
922 av_freep(&s->gain_cmd);
923 s->gain_cmd = gain_cmd;
924 } else {
925 av_freep(&gain_cmd);
926 }
927 } else if (!strcmp(cmd, "gain_entry")) {
928 char *gain_entry_cmd;
929
930 if (SELECT_GAIN_ENTRY(s) && !strcmp(SELECT_GAIN_ENTRY(s), args)) {
931 av_log(ctx, AV_LOG_DEBUG, "equal gain_entry, do not rebuild.\n");
932 return 0;
933 }
934
935 gain_entry_cmd = av_strdup(args);
936 if (!gain_entry_cmd)
937 return AVERROR(ENOMEM);
938
939 ret = generate_kernel(ctx, SELECT_GAIN(s), gain_entry_cmd);
940 if (ret >= 0) {
941 av_freep(&s->gain_entry_cmd);
942 s->gain_entry_cmd = gain_entry_cmd;
943 } else {
944 av_freep(&gain_entry_cmd);
945 }
946 }
947
948 return ret;
949 }
950
951 static const AVFilterPad firequalizer_inputs[] = {
952 {
953 .name = "default",
954 .config_props = config_input,
955 .filter_frame = filter_frame,
956 .type = AVMEDIA_TYPE_AUDIO,
957 .needs_writable = 1,
958 },
959 { NULL }
960 };
961
962 static const AVFilterPad firequalizer_outputs[] = {
963 {
964 .name = "default",
965 .request_frame = request_frame,
966 .type = AVMEDIA_TYPE_AUDIO,
967 },
968 { NULL }
969 };
970
971 AVFilter ff_af_firequalizer = {
972 .name = "firequalizer",
973 .description = NULL_IF_CONFIG_SMALL("Finite Impulse Response Equalizer."),
974 .uninit = uninit,
975 .query_formats = query_formats,
976 .process_command = process_command,
977 .priv_size = sizeof(FIREqualizerContext),
978 .inputs = firequalizer_inputs,
979 .outputs = firequalizer_outputs,
980 .priv_class = &firequalizer_class,
981 };
982