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/channel_layout.h"
22 #include "libavutil/opt.h"
23 #include "libavutil/eval.h"
24 #include "libavutil/avassert.h"
25 #include "libavcodec/avfft.h"
26 #include "avfilter.h"
27 #include "internal.h"
28 #include "audio.h"
29
30 #define RDFT_BITS_MIN 4
31 #define RDFT_BITS_MAX 16
32
33 enum WindowFunc {
34 WFUNC_RECTANGULAR,
35 WFUNC_HANN,
36 WFUNC_HAMMING,
37 WFUNC_BLACKMAN,
38 WFUNC_NUTTALL3,
39 WFUNC_MNUTTALL3,
40 WFUNC_NUTTALL,
41 WFUNC_BNUTTALL,
42 WFUNC_BHARRIS,
43 WFUNC_TUKEY,
44 NB_WFUNC
45 };
46
47 enum Scale {
48 SCALE_LINLIN,
49 SCALE_LINLOG,
50 SCALE_LOGLIN,
51 SCALE_LOGLOG,
52 NB_SCALE
53 };
54
55 #define NB_GAIN_ENTRY_MAX 4096
56 typedef struct GainEntry {
57 double freq;
58 double gain;
59 } GainEntry;
60
61 typedef struct OverlapIndex {
62 int buf_idx;
63 int overlap_idx;
64 } OverlapIndex;
65
66 typedef struct FIREqualizerContext {
67 const AVClass *class;
68
69 RDFTContext *analysis_rdft;
70 RDFTContext *analysis_irdft;
71 RDFTContext *rdft;
72 RDFTContext *irdft;
73 FFTContext *fft_ctx;
74 RDFTContext *cepstrum_rdft;
75 RDFTContext *cepstrum_irdft;
76 int analysis_rdft_len;
77 int rdft_len;
78 int cepstrum_len;
79
80 float *analysis_buf;
81 float *dump_buf;
82 float *kernel_tmp_buf;
83 float *kernel_buf;
84 float *cepstrum_buf;
85 float *conv_buf;
86 OverlapIndex *conv_idx;
87 int fir_len;
88 int nsamples_max;
89 int64_t next_pts;
90 int frame_nsamples_max;
91 int remaining;
92
93 char *gain_cmd;
94 char *gain_entry_cmd;
95 const char *gain;
96 const char *gain_entry;
97 double delay;
98 double accuracy;
99 int wfunc;
100 int fixed;
101 int multi;
102 int zero_phase;
103 int scale;
104 char *dumpfile;
105 int dumpscale;
106 int fft2;
107 int min_phase;
108
109 int nb_gain_entry;
110 int gain_entry_err;
111 GainEntry gain_entry_tbl[NB_GAIN_ENTRY_MAX];
112 } FIREqualizerContext;
113
114 #define OFFSET(x) offsetof(FIREqualizerContext, x)
115 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
116 #define TFLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
117
118 static const AVOption firequalizer_options[] = {
119 { "gain", "set gain curve", OFFSET(gain), AV_OPT_TYPE_STRING, { .str = "gain_interpolate(f)" }, 0, 0, TFLAGS },
120 { "gain_entry", "set gain entry", OFFSET(gain_entry), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, TFLAGS },
121 { "delay", "set delay", OFFSET(delay), AV_OPT_TYPE_DOUBLE, { .dbl = 0.01 }, 0.0, 1e10, FLAGS },
122 { "accuracy", "set accuracy", OFFSET(accuracy), AV_OPT_TYPE_DOUBLE, { .dbl = 5.0 }, 0.0, 1e10, FLAGS },
123 { "wfunc", "set window function", OFFSET(wfunc), AV_OPT_TYPE_INT, { .i64 = WFUNC_HANN }, 0, NB_WFUNC-1, FLAGS, "wfunc" },
124 { "rectangular", "rectangular window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_RECTANGULAR }, 0, 0, FLAGS, "wfunc" },
125 { "hann", "hann window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_HANN }, 0, 0, FLAGS, "wfunc" },
126 { "hamming", "hamming window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_HAMMING }, 0, 0, FLAGS, "wfunc" },
127 { "blackman", "blackman window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BLACKMAN }, 0, 0, FLAGS, "wfunc" },
128 { "nuttall3", "3-term nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_NUTTALL3 }, 0, 0, FLAGS, "wfunc" },
129 { "mnuttall3", "minimum 3-term nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_MNUTTALL3 }, 0, 0, FLAGS, "wfunc" },
130 { "nuttall", "nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_NUTTALL }, 0, 0, FLAGS, "wfunc" },
131 { "bnuttall", "blackman-nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BNUTTALL }, 0, 0, FLAGS, "wfunc" },
132 { "bharris", "blackman-harris window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BHARRIS }, 0, 0, FLAGS, "wfunc" },
133 { "tukey", "tukey window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_TUKEY }, 0, 0, FLAGS, "wfunc" },
134 { "fixed", "set fixed frame samples", OFFSET(fixed), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
135 { "multi", "set multi channels mode", OFFSET(multi), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
136 { "zero_phase", "set zero phase mode", OFFSET(zero_phase), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
137 { "scale", "set gain scale", OFFSET(scale), AV_OPT_TYPE_INT, { .i64 = SCALE_LINLOG }, 0, NB_SCALE-1, FLAGS, "scale" },
138 { "linlin", "linear-freq linear-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LINLIN }, 0, 0, FLAGS, "scale" },
139 { "linlog", "linear-freq logarithmic-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LINLOG }, 0, 0, FLAGS, "scale" },
140 { "loglin", "logarithmic-freq linear-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LOGLIN }, 0, 0, FLAGS, "scale" },
141 { "loglog", "logarithmic-freq logarithmic-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LOGLOG }, 0, 0, FLAGS, "scale" },
142 { "dumpfile", "set dump file", OFFSET(dumpfile), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, FLAGS },
143 { "dumpscale", "set dump scale", OFFSET(dumpscale), AV_OPT_TYPE_INT, { .i64 = SCALE_LINLOG }, 0, NB_SCALE-1, FLAGS, "scale" },
144 { "fft2", "set 2-channels fft", OFFSET(fft2), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
145 { "min_phase", "set minimum phase mode", OFFSET(min_phase), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
146 { NULL }
147 };
148
149 AVFILTER_DEFINE_CLASS(firequalizer);
150
common_uninit(FIREqualizerContext *s)151 static void common_uninit(FIREqualizerContext *s)
152 {
153 av_rdft_end(s->analysis_rdft);
154 av_rdft_end(s->analysis_irdft);
155 av_rdft_end(s->rdft);
156 av_rdft_end(s->irdft);
157 av_fft_end(s->fft_ctx);
158 av_rdft_end(s->cepstrum_rdft);
159 av_rdft_end(s->cepstrum_irdft);
160 s->analysis_rdft = s->analysis_irdft = s->rdft = s->irdft = NULL;
161 s->fft_ctx = NULL;
162 s->cepstrum_rdft = NULL;
163 s->cepstrum_irdft = NULL;
164
165 av_freep(&s->analysis_buf);
166 av_freep(&s->dump_buf);
167 av_freep(&s->kernel_tmp_buf);
168 av_freep(&s->kernel_buf);
169 av_freep(&s->cepstrum_buf);
170 av_freep(&s->conv_buf);
171 av_freep(&s->conv_idx);
172 }
173
uninit(AVFilterContext *ctx)174 static av_cold void uninit(AVFilterContext *ctx)
175 {
176 FIREqualizerContext *s = ctx->priv;
177
178 common_uninit(s);
179 av_freep(&s->gain_cmd);
180 av_freep(&s->gain_entry_cmd);
181 }
182
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)183 static void fast_convolute(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf, float *av_restrict conv_buf,
184 OverlapIndex *av_restrict idx, float *av_restrict data, int nsamples)
185 {
186 if (nsamples <= s->nsamples_max) {
187 float *buf = conv_buf + idx->buf_idx * s->rdft_len;
188 float *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
189 int center = s->fir_len/2;
190 int k;
191
192 memset(buf, 0, center * sizeof(*data));
193 memcpy(buf + center, data, nsamples * sizeof(*data));
194 memset(buf + center + nsamples, 0, (s->rdft_len - nsamples - center) * sizeof(*data));
195 av_rdft_calc(s->rdft, buf);
196
197 buf[0] *= kernel_buf[0];
198 buf[1] *= kernel_buf[s->rdft_len/2];
199 for (k = 1; k < s->rdft_len/2; k++) {
200 buf[2*k] *= kernel_buf[k];
201 buf[2*k+1] *= kernel_buf[k];
202 }
203
204 av_rdft_calc(s->irdft, buf);
205 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++)
206 buf[k] += obuf[k];
207 memcpy(data, buf, nsamples * sizeof(*data));
208 idx->buf_idx = !idx->buf_idx;
209 idx->overlap_idx = nsamples;
210 } else {
211 while (nsamples > s->nsamples_max * 2) {
212 fast_convolute(s, kernel_buf, conv_buf, idx, data, s->nsamples_max);
213 data += s->nsamples_max;
214 nsamples -= s->nsamples_max;
215 }
216 fast_convolute(s, kernel_buf, conv_buf, idx, data, nsamples/2);
217 fast_convolute(s, kernel_buf, conv_buf, idx, data + nsamples/2, nsamples - nsamples/2);
218 }
219 }
220
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)221 static void fast_convolute_nonlinear(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf,
222 float *av_restrict conv_buf, OverlapIndex *av_restrict idx,
223 float *av_restrict data, int nsamples)
224 {
225 if (nsamples <= s->nsamples_max) {
226 float *buf = conv_buf + idx->buf_idx * s->rdft_len;
227 float *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
228 int k;
229
230 memcpy(buf, data, nsamples * sizeof(*data));
231 memset(buf + nsamples, 0, (s->rdft_len - nsamples) * sizeof(*data));
232 av_rdft_calc(s->rdft, buf);
233
234 buf[0] *= kernel_buf[0];
235 buf[1] *= kernel_buf[1];
236 for (k = 2; k < s->rdft_len; k += 2) {
237 float re, im;
238 re = buf[k] * kernel_buf[k] - buf[k+1] * kernel_buf[k+1];
239 im = buf[k] * kernel_buf[k+1] + buf[k+1] * kernel_buf[k];
240 buf[k] = re;
241 buf[k+1] = im;
242 }
243
244 av_rdft_calc(s->irdft, buf);
245 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++)
246 buf[k] += obuf[k];
247 memcpy(data, buf, nsamples * sizeof(*data));
248 idx->buf_idx = !idx->buf_idx;
249 idx->overlap_idx = nsamples;
250 } else {
251 while (nsamples > s->nsamples_max * 2) {
252 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data, s->nsamples_max);
253 data += s->nsamples_max;
254 nsamples -= s->nsamples_max;
255 }
256 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data, nsamples/2);
257 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data + nsamples/2, nsamples - nsamples/2);
258 }
259 }
260
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)261 static void fast_convolute2(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf, FFTComplex *av_restrict conv_buf,
262 OverlapIndex *av_restrict idx, float *av_restrict data0, float *av_restrict data1, int nsamples)
263 {
264 if (nsamples <= s->nsamples_max) {
265 FFTComplex *buf = conv_buf + idx->buf_idx * s->rdft_len;
266 FFTComplex *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
267 int center = s->fir_len/2;
268 int k;
269 float tmp;
270
271 memset(buf, 0, center * sizeof(*buf));
272 for (k = 0; k < nsamples; k++) {
273 buf[center+k].re = data0[k];
274 buf[center+k].im = data1[k];
275 }
276 memset(buf + center + nsamples, 0, (s->rdft_len - nsamples - center) * sizeof(*buf));
277 av_fft_permute(s->fft_ctx, buf);
278 av_fft_calc(s->fft_ctx, buf);
279
280 /* swap re <-> im, do backward fft using forward fft_ctx */
281 /* normalize with 0.5f */
282 tmp = buf[0].re;
283 buf[0].re = 0.5f * kernel_buf[0] * buf[0].im;
284 buf[0].im = 0.5f * kernel_buf[0] * tmp;
285 for (k = 1; k < s->rdft_len/2; k++) {
286 int m = s->rdft_len - k;
287 tmp = buf[k].re;
288 buf[k].re = 0.5f * kernel_buf[k] * buf[k].im;
289 buf[k].im = 0.5f * kernel_buf[k] * tmp;
290 tmp = buf[m].re;
291 buf[m].re = 0.5f * kernel_buf[k] * buf[m].im;
292 buf[m].im = 0.5f * kernel_buf[k] * tmp;
293 }
294 tmp = buf[k].re;
295 buf[k].re = 0.5f * kernel_buf[k] * buf[k].im;
296 buf[k].im = 0.5f * kernel_buf[k] * tmp;
297
298 av_fft_permute(s->fft_ctx, buf);
299 av_fft_calc(s->fft_ctx, buf);
300
301 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++) {
302 buf[k].re += obuf[k].re;
303 buf[k].im += obuf[k].im;
304 }
305
306 /* swapped re <-> im */
307 for (k = 0; k < nsamples; k++) {
308 data0[k] = buf[k].im;
309 data1[k] = buf[k].re;
310 }
311 idx->buf_idx = !idx->buf_idx;
312 idx->overlap_idx = nsamples;
313 } else {
314 while (nsamples > s->nsamples_max * 2) {
315 fast_convolute2(s, kernel_buf, conv_buf, idx, data0, data1, s->nsamples_max);
316 data0 += s->nsamples_max;
317 data1 += s->nsamples_max;
318 nsamples -= s->nsamples_max;
319 }
320 fast_convolute2(s, kernel_buf, conv_buf, idx, data0, data1, nsamples/2);
321 fast_convolute2(s, kernel_buf, conv_buf, idx, data0 + nsamples/2, data1 + nsamples/2, nsamples - nsamples/2);
322 }
323 }
324
dump_fir(AVFilterContext *ctx, FILE *fp, int ch)325 static void dump_fir(AVFilterContext *ctx, FILE *fp, int ch)
326 {
327 FIREqualizerContext *s = ctx->priv;
328 int rate = ctx->inputs[0]->sample_rate;
329 int xlog = s->dumpscale == SCALE_LOGLIN || s->dumpscale == SCALE_LOGLOG;
330 int ylog = s->dumpscale == SCALE_LINLOG || s->dumpscale == SCALE_LOGLOG;
331 int x;
332 int center = s->fir_len / 2;
333 double delay = s->zero_phase ? 0.0 : (double) center / rate;
334 double vx, ya, yb;
335
336 if (!s->min_phase) {
337 s->analysis_buf[0] *= s->rdft_len/2;
338 for (x = 1; x <= center; x++) {
339 s->analysis_buf[x] *= s->rdft_len/2;
340 s->analysis_buf[s->analysis_rdft_len - x] *= s->rdft_len/2;
341 }
342 } else {
343 for (x = 0; x < s->fir_len; x++)
344 s->analysis_buf[x] *= s->rdft_len/2;
345 }
346
347 if (ch)
348 fprintf(fp, "\n\n");
349
350 fprintf(fp, "# time[%d] (time amplitude)\n", ch);
351
352 if (!s->min_phase) {
353 for (x = center; x > 0; x--)
354 fprintf(fp, "%15.10f %15.10f\n", delay - (double) x / rate, (double) s->analysis_buf[s->analysis_rdft_len - x]);
355
356 for (x = 0; x <= center; x++)
357 fprintf(fp, "%15.10f %15.10f\n", delay + (double)x / rate , (double) s->analysis_buf[x]);
358 } else {
359 for (x = 0; x < s->fir_len; x++)
360 fprintf(fp, "%15.10f %15.10f\n", (double)x / rate, (double) s->analysis_buf[x]);
361 }
362
363 av_rdft_calc(s->analysis_rdft, s->analysis_buf);
364
365 fprintf(fp, "\n\n# freq[%d] (frequency desired_gain actual_gain)\n", ch);
366
367 for (x = 0; x <= s->analysis_rdft_len/2; x++) {
368 int i = (x == s->analysis_rdft_len/2) ? 1 : 2 * x;
369 vx = (double)x * rate / s->analysis_rdft_len;
370 if (xlog)
371 vx = log2(0.05*vx);
372 ya = s->dump_buf[i];
373 yb = s->min_phase && (i > 1) ? hypotf(s->analysis_buf[i], s->analysis_buf[i+1]) : s->analysis_buf[i];
374 if (s->min_phase)
375 yb = fabs(yb);
376 if (ylog) {
377 ya = 20.0 * log10(fabs(ya));
378 yb = 20.0 * log10(fabs(yb));
379 }
380 fprintf(fp, "%17.10f %17.10f %17.10f\n", vx, ya, yb);
381 }
382 }
383
entry_func(void *p, double freq, double gain)384 static double entry_func(void *p, double freq, double gain)
385 {
386 AVFilterContext *ctx = p;
387 FIREqualizerContext *s = ctx->priv;
388
389 if (s->nb_gain_entry >= NB_GAIN_ENTRY_MAX) {
390 av_log(ctx, AV_LOG_ERROR, "entry table overflow.\n");
391 s->gain_entry_err = AVERROR(EINVAL);
392 return 0;
393 }
394
395 if (isnan(freq)) {
396 av_log(ctx, AV_LOG_ERROR, "nan frequency (%g, %g).\n", freq, gain);
397 s->gain_entry_err = AVERROR(EINVAL);
398 return 0;
399 }
400
401 if (s->nb_gain_entry > 0 && freq <= s->gain_entry_tbl[s->nb_gain_entry - 1].freq) {
402 av_log(ctx, AV_LOG_ERROR, "unsorted frequency (%g, %g).\n", freq, gain);
403 s->gain_entry_err = AVERROR(EINVAL);
404 return 0;
405 }
406
407 s->gain_entry_tbl[s->nb_gain_entry].freq = freq;
408 s->gain_entry_tbl[s->nb_gain_entry].gain = gain;
409 s->nb_gain_entry++;
410 return 0;
411 }
412
gain_entry_compare(const void *key, const void *memb)413 static int gain_entry_compare(const void *key, const void *memb)
414 {
415 const double *freq = key;
416 const GainEntry *entry = memb;
417
418 if (*freq < entry[0].freq)
419 return -1;
420 if (*freq > entry[1].freq)
421 return 1;
422 return 0;
423 }
424
gain_interpolate_func(void *p, double freq)425 static double gain_interpolate_func(void *p, double freq)
426 {
427 AVFilterContext *ctx = p;
428 FIREqualizerContext *s = ctx->priv;
429 GainEntry *res;
430 double d0, d1, d;
431
432 if (isnan(freq))
433 return freq;
434
435 if (!s->nb_gain_entry)
436 return 0;
437
438 if (freq <= s->gain_entry_tbl[0].freq)
439 return s->gain_entry_tbl[0].gain;
440
441 if (freq >= s->gain_entry_tbl[s->nb_gain_entry-1].freq)
442 return s->gain_entry_tbl[s->nb_gain_entry-1].gain;
443
444 res = bsearch(&freq, &s->gain_entry_tbl, s->nb_gain_entry - 1, sizeof(*res), gain_entry_compare);
445 av_assert0(res);
446
447 d = res[1].freq - res[0].freq;
448 d0 = freq - res[0].freq;
449 d1 = res[1].freq - freq;
450
451 if (d0 && d1)
452 return (d0 * res[1].gain + d1 * res[0].gain) / d;
453
454 if (d0)
455 return res[1].gain;
456
457 return res[0].gain;
458 }
459
cubic_interpolate_func(void *p, double freq)460 static double cubic_interpolate_func(void *p, double freq)
461 {
462 AVFilterContext *ctx = p;
463 FIREqualizerContext *s = ctx->priv;
464 GainEntry *res;
465 double x, x2, x3;
466 double a, b, c, d;
467 double m0, m1, m2, msum, unit;
468
469 if (!s->nb_gain_entry)
470 return 0;
471
472 if (freq <= s->gain_entry_tbl[0].freq)
473 return s->gain_entry_tbl[0].gain;
474
475 if (freq >= s->gain_entry_tbl[s->nb_gain_entry-1].freq)
476 return s->gain_entry_tbl[s->nb_gain_entry-1].gain;
477
478 res = bsearch(&freq, &s->gain_entry_tbl, s->nb_gain_entry - 1, sizeof(*res), gain_entry_compare);
479 av_assert0(res);
480
481 unit = res[1].freq - res[0].freq;
482 m0 = res != s->gain_entry_tbl ?
483 unit * (res[0].gain - res[-1].gain) / (res[0].freq - res[-1].freq) : 0;
484 m1 = res[1].gain - res[0].gain;
485 m2 = res != s->gain_entry_tbl + s->nb_gain_entry - 2 ?
486 unit * (res[2].gain - res[1].gain) / (res[2].freq - res[1].freq) : 0;
487
488 msum = fabs(m0) + fabs(m1);
489 m0 = msum > 0 ? (fabs(m0) * m1 + fabs(m1) * m0) / msum : 0;
490 msum = fabs(m1) + fabs(m2);
491 m1 = msum > 0 ? (fabs(m1) * m2 + fabs(m2) * m1) / msum : 0;
492
493 d = res[0].gain;
494 c = m0;
495 b = 3 * res[1].gain - m1 - 2 * c - 3 * d;
496 a = res[1].gain - b - c - d;
497
498 x = (freq - res[0].freq) / unit;
499 x2 = x * x;
500 x3 = x2 * x;
501
502 return a * x3 + b * x2 + c * x + d;
503 }
504
505 static const char *const var_names[] = {
506 "f",
507 "sr",
508 "ch",
509 "chid",
510 "chs",
511 "chlayout",
512 NULL
513 };
514
515 enum VarOffset {
516 VAR_F,
517 VAR_SR,
518 VAR_CH,
519 VAR_CHID,
520 VAR_CHS,
521 VAR_CHLAYOUT,
522 VAR_NB
523 };
524
generate_min_phase_kernel(FIREqualizerContext *s, float *rdft_buf)525 static void generate_min_phase_kernel(FIREqualizerContext *s, float *rdft_buf)
526 {
527 int k, cepstrum_len = s->cepstrum_len, rdft_len = s->rdft_len;
528 double norm = 2.0 / cepstrum_len;
529 double minval = 1e-7 / rdft_len;
530
531 memset(s->cepstrum_buf, 0, cepstrum_len * sizeof(*s->cepstrum_buf));
532 memcpy(s->cepstrum_buf, rdft_buf, rdft_len/2 * sizeof(*rdft_buf));
533 memcpy(s->cepstrum_buf + cepstrum_len - rdft_len/2, rdft_buf + rdft_len/2, rdft_len/2 * sizeof(*rdft_buf));
534
535 av_rdft_calc(s->cepstrum_rdft, s->cepstrum_buf);
536
537 s->cepstrum_buf[0] = log(FFMAX(s->cepstrum_buf[0], minval));
538 s->cepstrum_buf[1] = log(FFMAX(s->cepstrum_buf[1], minval));
539
540 for (k = 2; k < cepstrum_len; k += 2) {
541 s->cepstrum_buf[k] = log(FFMAX(s->cepstrum_buf[k], minval));
542 s->cepstrum_buf[k+1] = 0;
543 }
544
545 av_rdft_calc(s->cepstrum_irdft, s->cepstrum_buf);
546
547 memset(s->cepstrum_buf + cepstrum_len/2 + 1, 0, (cepstrum_len/2 - 1) * sizeof(*s->cepstrum_buf));
548 for (k = 1; k < cepstrum_len/2; k++)
549 s->cepstrum_buf[k] *= 2;
550
551 av_rdft_calc(s->cepstrum_rdft, s->cepstrum_buf);
552
553 s->cepstrum_buf[0] = exp(s->cepstrum_buf[0] * norm) * norm;
554 s->cepstrum_buf[1] = exp(s->cepstrum_buf[1] * norm) * norm;
555 for (k = 2; k < cepstrum_len; k += 2) {
556 double mag = exp(s->cepstrum_buf[k] * norm) * norm;
557 double ph = s->cepstrum_buf[k+1] * norm;
558 s->cepstrum_buf[k] = mag * cos(ph);
559 s->cepstrum_buf[k+1] = mag * sin(ph);
560 }
561
562 av_rdft_calc(s->cepstrum_irdft, s->cepstrum_buf);
563 memset(rdft_buf, 0, s->rdft_len * sizeof(*rdft_buf));
564 memcpy(rdft_buf, s->cepstrum_buf, s->fir_len * sizeof(*rdft_buf));
565
566 if (s->dumpfile) {
567 memset(s->analysis_buf, 0, s->analysis_rdft_len * sizeof(*s->analysis_buf));
568 memcpy(s->analysis_buf, s->cepstrum_buf, s->fir_len * sizeof(*s->analysis_buf));
569 }
570
571 }
572
generate_kernel(AVFilterContext *ctx, const char *gain, const char *gain_entry)573 static int generate_kernel(AVFilterContext *ctx, const char *gain, const char *gain_entry)
574 {
575 FIREqualizerContext *s = ctx->priv;
576 AVFilterLink *inlink = ctx->inputs[0];
577 const char *gain_entry_func_names[] = { "entry", NULL };
578 const char *gain_func_names[] = { "gain_interpolate", "cubic_interpolate", NULL };
579 double (*gain_entry_funcs[])(void *, double, double) = { entry_func, NULL };
580 double (*gain_funcs[])(void *, double) = { gain_interpolate_func, cubic_interpolate_func, NULL };
581 double vars[VAR_NB];
582 AVExpr *gain_expr;
583 int ret, k, center, ch;
584 int xlog = s->scale == SCALE_LOGLIN || s->scale == SCALE_LOGLOG;
585 int ylog = s->scale == SCALE_LINLOG || s->scale == SCALE_LOGLOG;
586 FILE *dump_fp = NULL;
587
588 s->nb_gain_entry = 0;
589 s->gain_entry_err = 0;
590 if (gain_entry) {
591 double result = 0.0;
592 ret = av_expr_parse_and_eval(&result, gain_entry, NULL, NULL, NULL, NULL,
593 gain_entry_func_names, gain_entry_funcs, ctx, 0, ctx);
594 if (ret < 0)
595 return ret;
596 if (s->gain_entry_err < 0)
597 return s->gain_entry_err;
598 }
599
600 av_log(ctx, AV_LOG_DEBUG, "nb_gain_entry = %d.\n", s->nb_gain_entry);
601
602 ret = av_expr_parse(&gain_expr, gain, var_names,
603 gain_func_names, gain_funcs, NULL, NULL, 0, ctx);
604 if (ret < 0)
605 return ret;
606
607 if (s->dumpfile && (!s->dump_buf || !s->analysis_rdft || !(dump_fp = avpriv_fopen_utf8(s->dumpfile, "w"))))
608 av_log(ctx, AV_LOG_WARNING, "dumping failed.\n");
609
610 vars[VAR_CHS] = inlink->ch_layout.nb_channels;
611 vars[VAR_CHLAYOUT] = inlink->ch_layout.order == AV_CHANNEL_ORDER_NATIVE ?
612 inlink->ch_layout.u.mask : 0;
613 vars[VAR_SR] = inlink->sample_rate;
614 for (ch = 0; ch < inlink->ch_layout.nb_channels; ch++) {
615 float *rdft_buf = s->kernel_tmp_buf + ch * s->rdft_len;
616 double result;
617 vars[VAR_CH] = ch;
618 vars[VAR_CHID] = av_channel_layout_channel_from_index(&inlink->ch_layout, ch);
619 vars[VAR_F] = 0.0;
620 if (xlog)
621 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
622 result = av_expr_eval(gain_expr, vars, ctx);
623 s->analysis_buf[0] = ylog ? pow(10.0, 0.05 * result) : result;
624
625 vars[VAR_F] = 0.5 * inlink->sample_rate;
626 if (xlog)
627 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
628 result = av_expr_eval(gain_expr, vars, ctx);
629 s->analysis_buf[1] = ylog ? pow(10.0, 0.05 * result) : result;
630
631 for (k = 1; k < s->analysis_rdft_len/2; k++) {
632 vars[VAR_F] = k * ((double)inlink->sample_rate /(double)s->analysis_rdft_len);
633 if (xlog)
634 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
635 result = av_expr_eval(gain_expr, vars, ctx);
636 s->analysis_buf[2*k] = ylog ? pow(10.0, 0.05 * result) : s->min_phase ? fabs(result) : result;
637 s->analysis_buf[2*k+1] = 0.0;
638 }
639
640 if (s->dump_buf)
641 memcpy(s->dump_buf, s->analysis_buf, s->analysis_rdft_len * sizeof(*s->analysis_buf));
642
643 av_rdft_calc(s->analysis_irdft, s->analysis_buf);
644 center = s->fir_len / 2;
645
646 for (k = 0; k <= center; k++) {
647 double u = k * (M_PI/center);
648 double win;
649 switch (s->wfunc) {
650 case WFUNC_RECTANGULAR:
651 win = 1.0;
652 break;
653 case WFUNC_HANN:
654 win = 0.5 + 0.5 * cos(u);
655 break;
656 case WFUNC_HAMMING:
657 win = 0.53836 + 0.46164 * cos(u);
658 break;
659 case WFUNC_BLACKMAN:
660 win = 0.42 + 0.5 * cos(u) + 0.08 * cos(2*u);
661 break;
662 case WFUNC_NUTTALL3:
663 win = 0.40897 + 0.5 * cos(u) + 0.09103 * cos(2*u);
664 break;
665 case WFUNC_MNUTTALL3:
666 win = 0.4243801 + 0.4973406 * cos(u) + 0.0782793 * cos(2*u);
667 break;
668 case WFUNC_NUTTALL:
669 win = 0.355768 + 0.487396 * cos(u) + 0.144232 * cos(2*u) + 0.012604 * cos(3*u);
670 break;
671 case WFUNC_BNUTTALL:
672 win = 0.3635819 + 0.4891775 * cos(u) + 0.1365995 * cos(2*u) + 0.0106411 * cos(3*u);
673 break;
674 case WFUNC_BHARRIS:
675 win = 0.35875 + 0.48829 * cos(u) + 0.14128 * cos(2*u) + 0.01168 * cos(3*u);
676 break;
677 case WFUNC_TUKEY:
678 win = (u <= 0.5 * M_PI) ? 1.0 : (0.5 + 0.5 * cos(2*u - M_PI));
679 break;
680 default:
681 av_assert0(0);
682 }
683 s->analysis_buf[k] *= (2.0/s->analysis_rdft_len) * (2.0/s->rdft_len) * win;
684 if (k)
685 s->analysis_buf[s->analysis_rdft_len - k] = s->analysis_buf[k];
686 }
687
688 memset(s->analysis_buf + center + 1, 0, (s->analysis_rdft_len - s->fir_len) * sizeof(*s->analysis_buf));
689 memcpy(rdft_buf, s->analysis_buf, s->rdft_len/2 * sizeof(*s->analysis_buf));
690 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));
691 if (s->min_phase)
692 generate_min_phase_kernel(s, rdft_buf);
693 av_rdft_calc(s->rdft, rdft_buf);
694
695 for (k = 0; k < s->rdft_len; k++) {
696 if (isnan(rdft_buf[k]) || isinf(rdft_buf[k])) {
697 av_log(ctx, AV_LOG_ERROR, "filter kernel contains nan or infinity.\n");
698 av_expr_free(gain_expr);
699 if (dump_fp)
700 fclose(dump_fp);
701 return AVERROR(EINVAL);
702 }
703 }
704
705 if (!s->min_phase) {
706 rdft_buf[s->rdft_len-1] = rdft_buf[1];
707 for (k = 0; k < s->rdft_len/2; k++)
708 rdft_buf[k] = rdft_buf[2*k];
709 rdft_buf[s->rdft_len/2] = rdft_buf[s->rdft_len-1];
710 }
711
712 if (dump_fp)
713 dump_fir(ctx, dump_fp, ch);
714
715 if (!s->multi)
716 break;
717 }
718
719 memcpy(s->kernel_buf, s->kernel_tmp_buf, (s->multi ? inlink->ch_layout.nb_channels : 1) * s->rdft_len * sizeof(*s->kernel_buf));
720 av_expr_free(gain_expr);
721 if (dump_fp)
722 fclose(dump_fp);
723 return 0;
724 }
725
726 #define SELECT_GAIN(s) (s->gain_cmd ? s->gain_cmd : s->gain)
727 #define SELECT_GAIN_ENTRY(s) (s->gain_entry_cmd ? s->gain_entry_cmd : s->gain_entry)
728
config_input(AVFilterLink *inlink)729 static int config_input(AVFilterLink *inlink)
730 {
731 AVFilterContext *ctx = inlink->dst;
732 FIREqualizerContext *s = ctx->priv;
733 int rdft_bits;
734
735 common_uninit(s);
736
737 s->next_pts = 0;
738 s->frame_nsamples_max = 0;
739
740 s->fir_len = FFMAX(2 * (int)(inlink->sample_rate * s->delay) + 1, 3);
741 s->remaining = s->fir_len - 1;
742
743 for (rdft_bits = RDFT_BITS_MIN; rdft_bits <= RDFT_BITS_MAX; rdft_bits++) {
744 s->rdft_len = 1 << rdft_bits;
745 s->nsamples_max = s->rdft_len - s->fir_len + 1;
746 if (s->nsamples_max * 2 >= s->fir_len)
747 break;
748 }
749
750 if (rdft_bits > RDFT_BITS_MAX) {
751 av_log(ctx, AV_LOG_ERROR, "too large delay, please decrease it.\n");
752 return AVERROR(EINVAL);
753 }
754
755 if (!(s->rdft = av_rdft_init(rdft_bits, DFT_R2C)) || !(s->irdft = av_rdft_init(rdft_bits, IDFT_C2R)))
756 return AVERROR(ENOMEM);
757
758 if (s->fft2 && !s->multi && inlink->ch_layout.nb_channels > 1 && !(s->fft_ctx = av_fft_init(rdft_bits, 0)))
759 return AVERROR(ENOMEM);
760
761 if (s->min_phase) {
762 int cepstrum_bits = rdft_bits + 2;
763 if (cepstrum_bits > RDFT_BITS_MAX) {
764 av_log(ctx, AV_LOG_ERROR, "too large delay, please decrease it.\n");
765 return AVERROR(EINVAL);
766 }
767
768 cepstrum_bits = FFMIN(RDFT_BITS_MAX, cepstrum_bits + 1);
769 s->cepstrum_rdft = av_rdft_init(cepstrum_bits, DFT_R2C);
770 s->cepstrum_irdft = av_rdft_init(cepstrum_bits, IDFT_C2R);
771 if (!s->cepstrum_rdft || !s->cepstrum_irdft)
772 return AVERROR(ENOMEM);
773
774 s->cepstrum_len = 1 << cepstrum_bits;
775 s->cepstrum_buf = av_malloc_array(s->cepstrum_len, sizeof(*s->cepstrum_buf));
776 if (!s->cepstrum_buf)
777 return AVERROR(ENOMEM);
778 }
779
780 for ( ; rdft_bits <= RDFT_BITS_MAX; rdft_bits++) {
781 s->analysis_rdft_len = 1 << rdft_bits;
782 if (inlink->sample_rate <= s->accuracy * s->analysis_rdft_len)
783 break;
784 }
785
786 if (rdft_bits > RDFT_BITS_MAX) {
787 av_log(ctx, AV_LOG_ERROR, "too small accuracy, please increase it.\n");
788 return AVERROR(EINVAL);
789 }
790
791 if (!(s->analysis_irdft = av_rdft_init(rdft_bits, IDFT_C2R)))
792 return AVERROR(ENOMEM);
793
794 if (s->dumpfile) {
795 s->analysis_rdft = av_rdft_init(rdft_bits, DFT_R2C);
796 s->dump_buf = av_malloc_array(s->analysis_rdft_len, sizeof(*s->dump_buf));
797 }
798
799 s->analysis_buf = av_malloc_array(s->analysis_rdft_len, sizeof(*s->analysis_buf));
800 s->kernel_tmp_buf = av_malloc_array(s->rdft_len * (s->multi ? inlink->ch_layout.nb_channels : 1), sizeof(*s->kernel_tmp_buf));
801 s->kernel_buf = av_malloc_array(s->rdft_len * (s->multi ? inlink->ch_layout.nb_channels : 1), sizeof(*s->kernel_buf));
802 s->conv_buf = av_calloc(2 * s->rdft_len * inlink->ch_layout.nb_channels, sizeof(*s->conv_buf));
803 s->conv_idx = av_calloc(inlink->ch_layout.nb_channels, sizeof(*s->conv_idx));
804 if (!s->analysis_buf || !s->kernel_tmp_buf || !s->kernel_buf || !s->conv_buf || !s->conv_idx)
805 return AVERROR(ENOMEM);
806
807 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",
808 inlink->sample_rate, inlink->ch_layout.nb_channels, s->analysis_rdft_len, s->rdft_len, s->fir_len, s->nsamples_max);
809
810 if (s->fixed)
811 inlink->min_samples = inlink->max_samples = s->nsamples_max;
812
813 return generate_kernel(ctx, SELECT_GAIN(s), SELECT_GAIN_ENTRY(s));
814 }
815
filter_frame(AVFilterLink *inlink, AVFrame *frame)816 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
817 {
818 AVFilterContext *ctx = inlink->dst;
819 FIREqualizerContext *s = ctx->priv;
820 int ch;
821
822 if (!s->min_phase) {
823 for (ch = 0; ch + 1 < inlink->ch_layout.nb_channels && s->fft_ctx; ch += 2) {
824 fast_convolute2(s, s->kernel_buf, (FFTComplex *)(s->conv_buf + 2 * ch * s->rdft_len),
825 s->conv_idx + ch, (float *) frame->extended_data[ch],
826 (float *) frame->extended_data[ch+1], frame->nb_samples);
827 }
828
829 for ( ; ch < inlink->ch_layout.nb_channels; ch++) {
830 fast_convolute(s, s->kernel_buf + (s->multi ? ch * s->rdft_len : 0),
831 s->conv_buf + 2 * ch * s->rdft_len, s->conv_idx + ch,
832 (float *) frame->extended_data[ch], frame->nb_samples);
833 }
834 } else {
835 for (ch = 0; ch < inlink->ch_layout.nb_channels; ch++) {
836 fast_convolute_nonlinear(s, s->kernel_buf + (s->multi ? ch * s->rdft_len : 0),
837 s->conv_buf + 2 * ch * s->rdft_len, s->conv_idx + ch,
838 (float *) frame->extended_data[ch], frame->nb_samples);
839 }
840 }
841
842 s->next_pts = AV_NOPTS_VALUE;
843 if (frame->pts != AV_NOPTS_VALUE) {
844 s->next_pts = frame->pts + av_rescale_q(frame->nb_samples, av_make_q(1, inlink->sample_rate), inlink->time_base);
845 if (s->zero_phase && !s->min_phase)
846 frame->pts -= av_rescale_q(s->fir_len/2, av_make_q(1, inlink->sample_rate), inlink->time_base);
847 }
848 s->frame_nsamples_max = FFMAX(s->frame_nsamples_max, frame->nb_samples);
849 return ff_filter_frame(ctx->outputs[0], frame);
850 }
851
request_frame(AVFilterLink *outlink)852 static int request_frame(AVFilterLink *outlink)
853 {
854 AVFilterContext *ctx = outlink->src;
855 FIREqualizerContext *s= ctx->priv;
856 int ret;
857
858 ret = ff_request_frame(ctx->inputs[0]);
859 if (ret == AVERROR_EOF && s->remaining > 0 && s->frame_nsamples_max > 0) {
860 AVFrame *frame = ff_get_audio_buffer(outlink, FFMIN(s->remaining, s->frame_nsamples_max));
861
862 if (!frame)
863 return AVERROR(ENOMEM);
864
865 av_samples_set_silence(frame->extended_data, 0, frame->nb_samples, outlink->ch_layout.nb_channels, frame->format);
866 frame->pts = s->next_pts;
867 s->remaining -= frame->nb_samples;
868 ret = filter_frame(ctx->inputs[0], frame);
869 }
870
871 return ret;
872 }
873
process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)874 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
875 char *res, int res_len, int flags)
876 {
877 FIREqualizerContext *s = ctx->priv;
878 int ret = AVERROR(ENOSYS);
879
880 if (!strcmp(cmd, "gain")) {
881 char *gain_cmd;
882
883 if (SELECT_GAIN(s) && !strcmp(SELECT_GAIN(s), args)) {
884 av_log(ctx, AV_LOG_DEBUG, "equal gain, do not rebuild.\n");
885 return 0;
886 }
887
888 gain_cmd = av_strdup(args);
889 if (!gain_cmd)
890 return AVERROR(ENOMEM);
891
892 ret = generate_kernel(ctx, gain_cmd, SELECT_GAIN_ENTRY(s));
893 if (ret >= 0) {
894 av_freep(&s->gain_cmd);
895 s->gain_cmd = gain_cmd;
896 } else {
897 av_freep(&gain_cmd);
898 }
899 } else if (!strcmp(cmd, "gain_entry")) {
900 char *gain_entry_cmd;
901
902 if (SELECT_GAIN_ENTRY(s) && !strcmp(SELECT_GAIN_ENTRY(s), args)) {
903 av_log(ctx, AV_LOG_DEBUG, "equal gain_entry, do not rebuild.\n");
904 return 0;
905 }
906
907 gain_entry_cmd = av_strdup(args);
908 if (!gain_entry_cmd)
909 return AVERROR(ENOMEM);
910
911 ret = generate_kernel(ctx, SELECT_GAIN(s), gain_entry_cmd);
912 if (ret >= 0) {
913 av_freep(&s->gain_entry_cmd);
914 s->gain_entry_cmd = gain_entry_cmd;
915 } else {
916 av_freep(&gain_entry_cmd);
917 }
918 }
919
920 return ret;
921 }
922
923 static const AVFilterPad firequalizer_inputs[] = {
924 {
925 .name = "default",
926 .flags = AVFILTERPAD_FLAG_NEEDS_WRITABLE,
927 .config_props = config_input,
928 .filter_frame = filter_frame,
929 .type = AVMEDIA_TYPE_AUDIO,
930 },
931 };
932
933 static const AVFilterPad firequalizer_outputs[] = {
934 {
935 .name = "default",
936 .request_frame = request_frame,
937 .type = AVMEDIA_TYPE_AUDIO,
938 },
939 };
940
941 const AVFilter ff_af_firequalizer = {
942 .name = "firequalizer",
943 .description = NULL_IF_CONFIG_SMALL("Finite Impulse Response Equalizer."),
944 .uninit = uninit,
945 .process_command = process_command,
946 .priv_size = sizeof(FIREqualizerContext),
947 FILTER_INPUTS(firequalizer_inputs),
948 FILTER_OUTPUTS(firequalizer_outputs),
949 FILTER_SINGLE_SAMPLEFMT(AV_SAMPLE_FMT_FLTP),
950 .priv_class = &firequalizer_class,
951 };
952