2 * Copyright (c) 2016 Muhammad Faiz <mfcc64@gmail.com>
4 * This file is part of FFmpeg.
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.
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.
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
21 #include "libavutil/opt.h"
22 #include "libavutil/eval.h"
23 #include "libavutil/avassert.h"
24 #include "libavcodec/avfft.h"
29 #define RDFT_BITS_MIN 4
30 #define RDFT_BITS_MAX 16
54 #define NB_GAIN_ENTRY_MAX 4096
55 typedef struct GainEntry {
60 typedef struct OverlapIndex {
65 typedef struct FIREqualizerContext {
68 RDFTContext *analysis_rdft;
69 RDFTContext *analysis_irdft;
73 RDFTContext *cepstrum_rdft;
74 RDFTContext *cepstrum_irdft;
75 int analysis_rdft_len;
81 float *kernel_tmp_buf;
85 OverlapIndex *conv_idx;
89 int frame_nsamples_max;
95 const char *gain_entry;
110 GainEntry gain_entry_tbl[NB_GAIN_ENTRY_MAX];
111 } FIREqualizerContext;
113 #define OFFSET(x) offsetof(FIREqualizerContext, x)
114 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
116 static const AVOption firequalizer_options[] = {
117 { "gain", "set gain curve", OFFSET(gain), AV_OPT_TYPE_STRING, { .str = "gain_interpolate(f)" }, 0, 0, FLAGS },
118 { "gain_entry", "set gain entry", OFFSET(gain_entry), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, FLAGS },
119 { "delay", "set delay", OFFSET(delay), AV_OPT_TYPE_DOUBLE, { .dbl = 0.01 }, 0.0, 1e10, FLAGS },
120 { "accuracy", "set accuracy", OFFSET(accuracy), AV_OPT_TYPE_DOUBLE, { .dbl = 5.0 }, 0.0, 1e10, FLAGS },
121 { "wfunc", "set window function", OFFSET(wfunc), AV_OPT_TYPE_INT, { .i64 = WFUNC_HANN }, 0, NB_WFUNC-1, FLAGS, "wfunc" },
122 { "rectangular", "rectangular window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_RECTANGULAR }, 0, 0, FLAGS, "wfunc" },
123 { "hann", "hann window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_HANN }, 0, 0, FLAGS, "wfunc" },
124 { "hamming", "hamming window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_HAMMING }, 0, 0, FLAGS, "wfunc" },
125 { "blackman", "blackman window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BLACKMAN }, 0, 0, FLAGS, "wfunc" },
126 { "nuttall3", "3-term nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_NUTTALL3 }, 0, 0, FLAGS, "wfunc" },
127 { "mnuttall3", "minimum 3-term nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_MNUTTALL3 }, 0, 0, FLAGS, "wfunc" },
128 { "nuttall", "nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_NUTTALL }, 0, 0, FLAGS, "wfunc" },
129 { "bnuttall", "blackman-nuttall window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BNUTTALL }, 0, 0, FLAGS, "wfunc" },
130 { "bharris", "blackman-harris window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_BHARRIS }, 0, 0, FLAGS, "wfunc" },
131 { "tukey", "tukey window", 0, AV_OPT_TYPE_CONST, { .i64 = WFUNC_TUKEY }, 0, 0, FLAGS, "wfunc" },
132 { "fixed", "set fixed frame samples", OFFSET(fixed), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
133 { "multi", "set multi channels mode", OFFSET(multi), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
134 { "zero_phase", "set zero phase mode", OFFSET(zero_phase), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
135 { "scale", "set gain scale", OFFSET(scale), AV_OPT_TYPE_INT, { .i64 = SCALE_LINLOG }, 0, NB_SCALE-1, FLAGS, "scale" },
136 { "linlin", "linear-freq linear-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LINLIN }, 0, 0, FLAGS, "scale" },
137 { "linlog", "linear-freq logarithmic-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LINLOG }, 0, 0, FLAGS, "scale" },
138 { "loglin", "logarithmic-freq linear-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LOGLIN }, 0, 0, FLAGS, "scale" },
139 { "loglog", "logarithmic-freq logarithmic-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LOGLOG }, 0, 0, FLAGS, "scale" },
140 { "dumpfile", "set dump file", OFFSET(dumpfile), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, FLAGS },
141 { "dumpscale", "set dump scale", OFFSET(dumpscale), AV_OPT_TYPE_INT, { .i64 = SCALE_LINLOG }, 0, NB_SCALE-1, FLAGS, "scale" },
142 { "fft2", "set 2-channels fft", OFFSET(fft2), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
143 { "min_phase", "set minimum phase mode", OFFSET(min_phase), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
147 AVFILTER_DEFINE_CLASS(firequalizer);
149 static void common_uninit(FIREqualizerContext *s)
151 av_rdft_end(s->analysis_rdft);
152 av_rdft_end(s->analysis_irdft);
153 av_rdft_end(s->rdft);
154 av_rdft_end(s->irdft);
155 av_fft_end(s->fft_ctx);
156 av_rdft_end(s->cepstrum_rdft);
157 av_rdft_end(s->cepstrum_irdft);
158 s->analysis_rdft = s->analysis_irdft = s->rdft = s->irdft = NULL;
160 s->cepstrum_rdft = NULL;
161 s->cepstrum_irdft = NULL;
163 av_freep(&s->analysis_buf);
164 av_freep(&s->dump_buf);
165 av_freep(&s->kernel_tmp_buf);
166 av_freep(&s->kernel_buf);
167 av_freep(&s->cepstrum_buf);
168 av_freep(&s->conv_buf);
169 av_freep(&s->conv_idx);
172 static av_cold void uninit(AVFilterContext *ctx)
174 FIREqualizerContext *s = ctx->priv;
177 av_freep(&s->gain_cmd);
178 av_freep(&s->gain_entry_cmd);
181 static int query_formats(AVFilterContext *ctx)
183 AVFilterChannelLayouts *layouts;
184 AVFilterFormats *formats;
185 static const enum AVSampleFormat sample_fmts[] = {
191 layouts = ff_all_channel_counts();
193 return AVERROR(ENOMEM);
194 ret = ff_set_common_channel_layouts(ctx, layouts);
198 formats = ff_make_format_list(sample_fmts);
200 return AVERROR(ENOMEM);
201 ret = ff_set_common_formats(ctx, formats);
205 formats = ff_all_samplerates();
207 return AVERROR(ENOMEM);
208 return ff_set_common_samplerates(ctx, formats);
211 static void fast_convolute(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf, float *av_restrict conv_buf,
212 OverlapIndex *av_restrict idx, float *av_restrict data, int nsamples)
214 if (nsamples <= s->nsamples_max) {
215 float *buf = conv_buf + idx->buf_idx * s->rdft_len;
216 float *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
217 int center = s->fir_len/2;
220 memset(buf, 0, center * sizeof(*data));
221 memcpy(buf + center, data, nsamples * sizeof(*data));
222 memset(buf + center + nsamples, 0, (s->rdft_len - nsamples - center) * sizeof(*data));
223 av_rdft_calc(s->rdft, buf);
225 buf[0] *= kernel_buf[0];
226 buf[1] *= kernel_buf[s->rdft_len/2];
227 for (k = 1; k < s->rdft_len/2; k++) {
228 buf[2*k] *= kernel_buf[k];
229 buf[2*k+1] *= kernel_buf[k];
232 av_rdft_calc(s->irdft, buf);
233 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++)
235 memcpy(data, buf, nsamples * sizeof(*data));
236 idx->buf_idx = !idx->buf_idx;
237 idx->overlap_idx = nsamples;
239 while (nsamples > s->nsamples_max * 2) {
240 fast_convolute(s, kernel_buf, conv_buf, idx, data, s->nsamples_max);
241 data += s->nsamples_max;
242 nsamples -= s->nsamples_max;
244 fast_convolute(s, kernel_buf, conv_buf, idx, data, nsamples/2);
245 fast_convolute(s, kernel_buf, conv_buf, idx, data + nsamples/2, nsamples - nsamples/2);
249 static void fast_convolute_nonlinear(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf,
250 float *av_restrict conv_buf, OverlapIndex *av_restrict idx,
251 float *av_restrict data, int nsamples)
253 if (nsamples <= s->nsamples_max) {
254 float *buf = conv_buf + idx->buf_idx * s->rdft_len;
255 float *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
258 memcpy(buf, data, nsamples * sizeof(*data));
259 memset(buf + nsamples, 0, (s->rdft_len - nsamples) * sizeof(*data));
260 av_rdft_calc(s->rdft, buf);
262 buf[0] *= kernel_buf[0];
263 buf[1] *= kernel_buf[1];
264 for (k = 2; k < s->rdft_len; k += 2) {
266 re = buf[k] * kernel_buf[k] - buf[k+1] * kernel_buf[k+1];
267 im = buf[k] * kernel_buf[k+1] + buf[k+1] * kernel_buf[k];
272 av_rdft_calc(s->irdft, buf);
273 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++)
275 memcpy(data, buf, nsamples * sizeof(*data));
276 idx->buf_idx = !idx->buf_idx;
277 idx->overlap_idx = nsamples;
279 while (nsamples > s->nsamples_max * 2) {
280 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data, s->nsamples_max);
281 data += s->nsamples_max;
282 nsamples -= s->nsamples_max;
284 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data, nsamples/2);
285 fast_convolute_nonlinear(s, kernel_buf, conv_buf, idx, data + nsamples/2, nsamples - nsamples/2);
289 static void fast_convolute2(FIREqualizerContext *av_restrict s, const float *av_restrict kernel_buf, FFTComplex *av_restrict conv_buf,
290 OverlapIndex *av_restrict idx, float *av_restrict data0, float *av_restrict data1, int nsamples)
292 if (nsamples <= s->nsamples_max) {
293 FFTComplex *buf = conv_buf + idx->buf_idx * s->rdft_len;
294 FFTComplex *obuf = conv_buf + !idx->buf_idx * s->rdft_len + idx->overlap_idx;
295 int center = s->fir_len/2;
299 memset(buf, 0, center * sizeof(*buf));
300 for (k = 0; k < nsamples; k++) {
301 buf[center+k].re = data0[k];
302 buf[center+k].im = data1[k];
304 memset(buf + center + nsamples, 0, (s->rdft_len - nsamples - center) * sizeof(*buf));
305 av_fft_permute(s->fft_ctx, buf);
306 av_fft_calc(s->fft_ctx, buf);
308 /* swap re <-> im, do backward fft using forward fft_ctx */
309 /* normalize with 0.5f */
311 buf[0].re = 0.5f * kernel_buf[0] * buf[0].im;
312 buf[0].im = 0.5f * kernel_buf[0] * tmp;
313 for (k = 1; k < s->rdft_len/2; k++) {
314 int m = s->rdft_len - k;
316 buf[k].re = 0.5f * kernel_buf[k] * buf[k].im;
317 buf[k].im = 0.5f * kernel_buf[k] * tmp;
319 buf[m].re = 0.5f * kernel_buf[k] * buf[m].im;
320 buf[m].im = 0.5f * kernel_buf[k] * tmp;
323 buf[k].re = 0.5f * kernel_buf[k] * buf[k].im;
324 buf[k].im = 0.5f * kernel_buf[k] * tmp;
326 av_fft_permute(s->fft_ctx, buf);
327 av_fft_calc(s->fft_ctx, buf);
329 for (k = 0; k < s->rdft_len - idx->overlap_idx; k++) {
330 buf[k].re += obuf[k].re;
331 buf[k].im += obuf[k].im;
334 /* swapped re <-> im */
335 for (k = 0; k < nsamples; k++) {
336 data0[k] = buf[k].im;
337 data1[k] = buf[k].re;
339 idx->buf_idx = !idx->buf_idx;
340 idx->overlap_idx = nsamples;
342 while (nsamples > s->nsamples_max * 2) {
343 fast_convolute2(s, kernel_buf, conv_buf, idx, data0, data1, s->nsamples_max);
344 data0 += s->nsamples_max;
345 data1 += s->nsamples_max;
346 nsamples -= s->nsamples_max;
348 fast_convolute2(s, kernel_buf, conv_buf, idx, data0, data1, nsamples/2);
349 fast_convolute2(s, kernel_buf, conv_buf, idx, data0 + nsamples/2, data1 + nsamples/2, nsamples - nsamples/2);
353 static void dump_fir(AVFilterContext *ctx, FILE *fp, int ch)
355 FIREqualizerContext *s = ctx->priv;
356 int rate = ctx->inputs[0]->sample_rate;
357 int xlog = s->dumpscale == SCALE_LOGLIN || s->dumpscale == SCALE_LOGLOG;
358 int ylog = s->dumpscale == SCALE_LINLOG || s->dumpscale == SCALE_LOGLOG;
360 int center = s->fir_len / 2;
361 double delay = s->zero_phase ? 0.0 : (double) center / rate;
365 s->analysis_buf[0] *= s->rdft_len/2;
366 for (x = 1; x <= center; x++) {
367 s->analysis_buf[x] *= s->rdft_len/2;
368 s->analysis_buf[s->analysis_rdft_len - x] *= s->rdft_len/2;
371 for (x = 0; x < s->fir_len; x++)
372 s->analysis_buf[x] *= s->rdft_len/2;
378 fprintf(fp, "# time[%d] (time amplitude)\n", ch);
381 for (x = center; x > 0; x--)
382 fprintf(fp, "%15.10f %15.10f\n", delay - (double) x / rate, (double) s->analysis_buf[s->analysis_rdft_len - x]);
384 for (x = 0; x <= center; x++)
385 fprintf(fp, "%15.10f %15.10f\n", delay + (double)x / rate , (double) s->analysis_buf[x]);
387 for (x = 0; x < s->fir_len; x++)
388 fprintf(fp, "%15.10f %15.10f\n", (double)x / rate, (double) s->analysis_buf[x]);
391 av_rdft_calc(s->analysis_rdft, s->analysis_buf);
393 fprintf(fp, "\n\n# freq[%d] (frequency desired_gain actual_gain)\n", ch);
395 for (x = 0; x <= s->analysis_rdft_len/2; x++) {
396 int i = (x == s->analysis_rdft_len/2) ? 1 : 2 * x;
397 vx = (double)x * rate / s->analysis_rdft_len;
401 yb = s->min_phase && (i > 1) ? hypotf(s->analysis_buf[i], s->analysis_buf[i+1]) : s->analysis_buf[i];
405 ya = 20.0 * log10(fabs(ya));
406 yb = 20.0 * log10(fabs(yb));
408 fprintf(fp, "%17.10f %17.10f %17.10f\n", vx, ya, yb);
412 static double entry_func(void *p, double freq, double gain)
414 AVFilterContext *ctx = p;
415 FIREqualizerContext *s = ctx->priv;
417 if (s->nb_gain_entry >= NB_GAIN_ENTRY_MAX) {
418 av_log(ctx, AV_LOG_ERROR, "entry table overflow.\n");
419 s->gain_entry_err = AVERROR(EINVAL);
424 av_log(ctx, AV_LOG_ERROR, "nan frequency (%g, %g).\n", freq, gain);
425 s->gain_entry_err = AVERROR(EINVAL);
429 if (s->nb_gain_entry > 0 && freq <= s->gain_entry_tbl[s->nb_gain_entry - 1].freq) {
430 av_log(ctx, AV_LOG_ERROR, "unsorted frequency (%g, %g).\n", freq, gain);
431 s->gain_entry_err = AVERROR(EINVAL);
435 s->gain_entry_tbl[s->nb_gain_entry].freq = freq;
436 s->gain_entry_tbl[s->nb_gain_entry].gain = gain;
441 static int gain_entry_compare(const void *key, const void *memb)
443 const double *freq = key;
444 const GainEntry *entry = memb;
446 if (*freq < entry[0].freq)
448 if (*freq > entry[1].freq)
453 static double gain_interpolate_func(void *p, double freq)
455 AVFilterContext *ctx = p;
456 FIREqualizerContext *s = ctx->priv;
463 if (!s->nb_gain_entry)
466 if (freq <= s->gain_entry_tbl[0].freq)
467 return s->gain_entry_tbl[0].gain;
469 if (freq >= s->gain_entry_tbl[s->nb_gain_entry-1].freq)
470 return s->gain_entry_tbl[s->nb_gain_entry-1].gain;
472 res = bsearch(&freq, &s->gain_entry_tbl, s->nb_gain_entry - 1, sizeof(*res), gain_entry_compare);
475 d = res[1].freq - res[0].freq;
476 d0 = freq - res[0].freq;
477 d1 = res[1].freq - freq;
480 return (d0 * res[1].gain + d1 * res[0].gain) / d;
488 static double cubic_interpolate_func(void *p, double freq)
490 AVFilterContext *ctx = p;
491 FIREqualizerContext *s = ctx->priv;
495 double m0, m1, m2, msum, unit;
497 if (!s->nb_gain_entry)
500 if (freq <= s->gain_entry_tbl[0].freq)
501 return s->gain_entry_tbl[0].gain;
503 if (freq >= s->gain_entry_tbl[s->nb_gain_entry-1].freq)
504 return s->gain_entry_tbl[s->nb_gain_entry-1].gain;
506 res = bsearch(&freq, &s->gain_entry_tbl, s->nb_gain_entry - 1, sizeof(*res), gain_entry_compare);
509 unit = res[1].freq - res[0].freq;
510 m0 = res != s->gain_entry_tbl ?
511 unit * (res[0].gain - res[-1].gain) / (res[0].freq - res[-1].freq) : 0;
512 m1 = res[1].gain - res[0].gain;
513 m2 = res != s->gain_entry_tbl + s->nb_gain_entry - 2 ?
514 unit * (res[2].gain - res[1].gain) / (res[2].freq - res[1].freq) : 0;
516 msum = fabs(m0) + fabs(m1);
517 m0 = msum > 0 ? (fabs(m0) * m1 + fabs(m1) * m0) / msum : 0;
518 msum = fabs(m1) + fabs(m2);
519 m1 = msum > 0 ? (fabs(m1) * m2 + fabs(m2) * m1) / msum : 0;
523 b = 3 * res[1].gain - m1 - 2 * c - 3 * d;
524 a = res[1].gain - b - c - d;
526 x = (freq - res[0].freq) / unit;
530 return a * x3 + b * x2 + c * x + d;
533 static const char *const var_names[] = {
553 static void generate_min_phase_kernel(FIREqualizerContext *s, float *rdft_buf)
555 int k, cepstrum_len = s->cepstrum_len, rdft_len = s->rdft_len;
556 double norm = 2.0 / cepstrum_len;
557 double minval = 1e-7 / rdft_len;
559 memset(s->cepstrum_buf, 0, cepstrum_len * sizeof(*s->cepstrum_buf));
560 memcpy(s->cepstrum_buf, rdft_buf, rdft_len/2 * sizeof(*rdft_buf));
561 memcpy(s->cepstrum_buf + cepstrum_len - rdft_len/2, rdft_buf + rdft_len/2, rdft_len/2 * sizeof(*rdft_buf));
563 av_rdft_calc(s->cepstrum_rdft, s->cepstrum_buf);
565 s->cepstrum_buf[0] = log(FFMAX(s->cepstrum_buf[0], minval));
566 s->cepstrum_buf[1] = log(FFMAX(s->cepstrum_buf[1], minval));
568 for (k = 2; k < cepstrum_len; k += 2) {
569 s->cepstrum_buf[k] = log(FFMAX(s->cepstrum_buf[k], minval));
570 s->cepstrum_buf[k+1] = 0;
573 av_rdft_calc(s->cepstrum_irdft, s->cepstrum_buf);
575 memset(s->cepstrum_buf + cepstrum_len/2 + 1, 0, (cepstrum_len/2 - 1) * sizeof(*s->cepstrum_buf));
576 for (k = 1; k < cepstrum_len/2; k++)
577 s->cepstrum_buf[k] *= 2;
579 av_rdft_calc(s->cepstrum_rdft, s->cepstrum_buf);
581 s->cepstrum_buf[0] = exp(s->cepstrum_buf[0] * norm) * norm;
582 s->cepstrum_buf[1] = exp(s->cepstrum_buf[1] * norm) * norm;
583 for (k = 2; k < cepstrum_len; k += 2) {
584 double mag = exp(s->cepstrum_buf[k] * norm) * norm;
585 double ph = s->cepstrum_buf[k+1] * norm;
586 s->cepstrum_buf[k] = mag * cos(ph);
587 s->cepstrum_buf[k+1] = mag * sin(ph);
590 av_rdft_calc(s->cepstrum_irdft, s->cepstrum_buf);
591 memset(rdft_buf, 0, s->rdft_len * sizeof(*rdft_buf));
592 memcpy(rdft_buf, s->cepstrum_buf, s->fir_len * sizeof(*rdft_buf));
595 memset(s->analysis_buf, 0, s->analysis_rdft_len * sizeof(*s->analysis_buf));
596 memcpy(s->analysis_buf, s->cepstrum_buf, s->fir_len * sizeof(*s->analysis_buf));
601 static int generate_kernel(AVFilterContext *ctx, const char *gain, const char *gain_entry)
603 FIREqualizerContext *s = ctx->priv;
604 AVFilterLink *inlink = ctx->inputs[0];
605 const char *gain_entry_func_names[] = { "entry", NULL };
606 const char *gain_func_names[] = { "gain_interpolate", "cubic_interpolate", NULL };
607 double (*gain_entry_funcs[])(void *, double, double) = { entry_func, NULL };
608 double (*gain_funcs[])(void *, double) = { gain_interpolate_func, cubic_interpolate_func, NULL };
611 int ret, k, center, ch;
612 int xlog = s->scale == SCALE_LOGLIN || s->scale == SCALE_LOGLOG;
613 int ylog = s->scale == SCALE_LINLOG || s->scale == SCALE_LOGLOG;
614 FILE *dump_fp = NULL;
616 s->nb_gain_entry = 0;
617 s->gain_entry_err = 0;
620 ret = av_expr_parse_and_eval(&result, gain_entry, NULL, NULL, NULL, NULL,
621 gain_entry_func_names, gain_entry_funcs, ctx, 0, ctx);
624 if (s->gain_entry_err < 0)
625 return s->gain_entry_err;
628 av_log(ctx, AV_LOG_DEBUG, "nb_gain_entry = %d.\n", s->nb_gain_entry);
630 ret = av_expr_parse(&gain_expr, gain, var_names,
631 gain_func_names, gain_funcs, NULL, NULL, 0, ctx);
635 if (s->dumpfile && (!s->dump_buf || !s->analysis_rdft || !(dump_fp = fopen(s->dumpfile, "w"))))
636 av_log(ctx, AV_LOG_WARNING, "dumping failed.\n");
638 vars[VAR_CHS] = inlink->channels;
639 vars[VAR_CHLAYOUT] = inlink->channel_layout;
640 vars[VAR_SR] = inlink->sample_rate;
641 for (ch = 0; ch < inlink->channels; ch++) {
642 float *rdft_buf = s->kernel_tmp_buf + ch * s->rdft_len;
645 vars[VAR_CHID] = av_channel_layout_extract_channel(inlink->channel_layout, ch);
648 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
649 result = av_expr_eval(gain_expr, vars, ctx);
650 s->analysis_buf[0] = ylog ? pow(10.0, 0.05 * result) : result;
652 vars[VAR_F] = 0.5 * inlink->sample_rate;
654 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
655 result = av_expr_eval(gain_expr, vars, ctx);
656 s->analysis_buf[1] = ylog ? pow(10.0, 0.05 * result) : result;
658 for (k = 1; k < s->analysis_rdft_len/2; k++) {
659 vars[VAR_F] = k * ((double)inlink->sample_rate /(double)s->analysis_rdft_len);
661 vars[VAR_F] = log2(0.05 * vars[VAR_F]);
662 result = av_expr_eval(gain_expr, vars, ctx);
663 s->analysis_buf[2*k] = ylog ? pow(10.0, 0.05 * result) : s->min_phase ? fabs(result) : result;
664 s->analysis_buf[2*k+1] = 0.0;
668 memcpy(s->dump_buf, s->analysis_buf, s->analysis_rdft_len * sizeof(*s->analysis_buf));
670 av_rdft_calc(s->analysis_irdft, s->analysis_buf);
671 center = s->fir_len / 2;
673 for (k = 0; k <= center; k++) {
674 double u = k * (M_PI/center);
677 case WFUNC_RECTANGULAR:
681 win = 0.5 + 0.5 * cos(u);
684 win = 0.53836 + 0.46164 * cos(u);
687 win = 0.42 + 0.5 * cos(u) + 0.08 * cos(2*u);
690 win = 0.40897 + 0.5 * cos(u) + 0.09103 * cos(2*u);
692 case WFUNC_MNUTTALL3:
693 win = 0.4243801 + 0.4973406 * cos(u) + 0.0782793 * cos(2*u);
696 win = 0.355768 + 0.487396 * cos(u) + 0.144232 * cos(2*u) + 0.012604 * cos(3*u);
699 win = 0.3635819 + 0.4891775 * cos(u) + 0.1365995 * cos(2*u) + 0.0106411 * cos(3*u);
702 win = 0.35875 + 0.48829 * cos(u) + 0.14128 * cos(2*u) + 0.01168 * cos(3*u);
705 win = (u <= 0.5 * M_PI) ? 1.0 : (0.5 + 0.5 * cos(2*u - M_PI));
710 s->analysis_buf[k] *= (2.0/s->analysis_rdft_len) * (2.0/s->rdft_len) * win;
712 s->analysis_buf[s->analysis_rdft_len - k] = s->analysis_buf[k];
715 memset(s->analysis_buf + center + 1, 0, (s->analysis_rdft_len - s->fir_len) * sizeof(*s->analysis_buf));
716 memcpy(rdft_buf, s->analysis_buf, s->rdft_len/2 * sizeof(*s->analysis_buf));
717 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 generate_min_phase_kernel(s, rdft_buf);
720 av_rdft_calc(s->rdft, rdft_buf);
722 for (k = 0; k < s->rdft_len; k++) {
723 if (isnan(rdft_buf[k]) || isinf(rdft_buf[k])) {
724 av_log(ctx, AV_LOG_ERROR, "filter kernel contains nan or infinity.\n");
725 av_expr_free(gain_expr);
728 return AVERROR(EINVAL);
733 rdft_buf[s->rdft_len-1] = rdft_buf[1];
734 for (k = 0; k < s->rdft_len/2; k++)
735 rdft_buf[k] = rdft_buf[2*k];
736 rdft_buf[s->rdft_len/2] = rdft_buf[s->rdft_len-1];
740 dump_fir(ctx, dump_fp, ch);
746 memcpy(s->kernel_buf, s->kernel_tmp_buf, (s->multi ? inlink->channels : 1) * s->rdft_len * sizeof(*s->kernel_buf));
747 av_expr_free(gain_expr);
753 #define SELECT_GAIN(s) (s->gain_cmd ? s->gain_cmd : s->gain)
754 #define SELECT_GAIN_ENTRY(s) (s->gain_entry_cmd ? s->gain_entry_cmd : s->gain_entry)
756 static int config_input(AVFilterLink *inlink)
758 AVFilterContext *ctx = inlink->dst;
759 FIREqualizerContext *s = ctx->priv;
765 s->frame_nsamples_max = 0;
767 s->fir_len = FFMAX(2 * (int)(inlink->sample_rate * s->delay) + 1, 3);
768 s->remaining = s->fir_len - 1;
770 for (rdft_bits = RDFT_BITS_MIN; rdft_bits <= RDFT_BITS_MAX; rdft_bits++) {
771 s->rdft_len = 1 << rdft_bits;
772 s->nsamples_max = s->rdft_len - s->fir_len + 1;
773 if (s->nsamples_max * 2 >= s->fir_len)
777 if (rdft_bits > RDFT_BITS_MAX) {
778 av_log(ctx, AV_LOG_ERROR, "too large delay, please decrease it.\n");
779 return AVERROR(EINVAL);
782 if (!(s->rdft = av_rdft_init(rdft_bits, DFT_R2C)) || !(s->irdft = av_rdft_init(rdft_bits, IDFT_C2R)))
783 return AVERROR(ENOMEM);
785 if (s->fft2 && !s->multi && inlink->channels > 1 && !(s->fft_ctx = av_fft_init(rdft_bits, 0)))
786 return AVERROR(ENOMEM);
789 int cepstrum_bits = rdft_bits + 2;
790 if (cepstrum_bits > RDFT_BITS_MAX) {
791 av_log(ctx, AV_LOG_ERROR, "too large delay, please decrease it.\n");
792 return AVERROR(EINVAL);
795 cepstrum_bits = FFMIN(RDFT_BITS_MAX, cepstrum_bits + 1);
796 s->cepstrum_rdft = av_rdft_init(cepstrum_bits, DFT_R2C);
797 s->cepstrum_irdft = av_rdft_init(cepstrum_bits, IDFT_C2R);
798 if (!s->cepstrum_rdft || !s->cepstrum_irdft)
799 return AVERROR(ENOMEM);
801 s->cepstrum_len = 1 << cepstrum_bits;
802 s->cepstrum_buf = av_malloc_array(s->cepstrum_len, sizeof(*s->cepstrum_buf));
803 if (!s->cepstrum_buf)
804 return AVERROR(ENOMEM);
807 for ( ; rdft_bits <= RDFT_BITS_MAX; rdft_bits++) {
808 s->analysis_rdft_len = 1 << rdft_bits;
809 if (inlink->sample_rate <= s->accuracy * s->analysis_rdft_len)
813 if (rdft_bits > RDFT_BITS_MAX) {
814 av_log(ctx, AV_LOG_ERROR, "too small accuracy, please increase it.\n");
815 return AVERROR(EINVAL);
818 if (!(s->analysis_irdft = av_rdft_init(rdft_bits, IDFT_C2R)))
819 return AVERROR(ENOMEM);
822 s->analysis_rdft = av_rdft_init(rdft_bits, DFT_R2C);
823 s->dump_buf = av_malloc_array(s->analysis_rdft_len, sizeof(*s->dump_buf));
826 s->analysis_buf = av_malloc_array(s->analysis_rdft_len, sizeof(*s->analysis_buf));
827 s->kernel_tmp_buf = av_malloc_array(s->rdft_len * (s->multi ? inlink->channels : 1), sizeof(*s->kernel_tmp_buf));
828 s->kernel_buf = av_malloc_array(s->rdft_len * (s->multi ? inlink->channels : 1), sizeof(*s->kernel_buf));
829 s->conv_buf = av_calloc(2 * s->rdft_len * inlink->channels, sizeof(*s->conv_buf));
830 s->conv_idx = av_calloc(inlink->channels, sizeof(*s->conv_idx));
831 if (!s->analysis_buf || !s->kernel_tmp_buf || !s->kernel_buf || !s->conv_buf || !s->conv_idx)
832 return AVERROR(ENOMEM);
834 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",
835 inlink->sample_rate, inlink->channels, s->analysis_rdft_len, s->rdft_len, s->fir_len, s->nsamples_max);
838 inlink->min_samples = inlink->max_samples = inlink->partial_buf_size = s->nsamples_max;
840 return generate_kernel(ctx, SELECT_GAIN(s), SELECT_GAIN_ENTRY(s));
843 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
845 AVFilterContext *ctx = inlink->dst;
846 FIREqualizerContext *s = ctx->priv;
850 for (ch = 0; ch + 1 < inlink->channels && s->fft_ctx; ch += 2) {
851 fast_convolute2(s, s->kernel_buf, (FFTComplex *)(s->conv_buf + 2 * ch * s->rdft_len),
852 s->conv_idx + ch, (float *) frame->extended_data[ch],
853 (float *) frame->extended_data[ch+1], frame->nb_samples);
856 for ( ; ch < inlink->channels; ch++) {
857 fast_convolute(s, s->kernel_buf + (s->multi ? ch * s->rdft_len : 0),
858 s->conv_buf + 2 * ch * s->rdft_len, s->conv_idx + ch,
859 (float *) frame->extended_data[ch], frame->nb_samples);
862 for (ch = 0; ch < inlink->channels; ch++) {
863 fast_convolute_nonlinear(s, s->kernel_buf + (s->multi ? ch * s->rdft_len : 0),
864 s->conv_buf + 2 * ch * s->rdft_len, s->conv_idx + ch,
865 (float *) frame->extended_data[ch], frame->nb_samples);
869 s->next_pts = AV_NOPTS_VALUE;
870 if (frame->pts != AV_NOPTS_VALUE) {
871 s->next_pts = frame->pts + av_rescale_q(frame->nb_samples, av_make_q(1, inlink->sample_rate), inlink->time_base);
872 if (s->zero_phase && !s->min_phase)
873 frame->pts -= av_rescale_q(s->fir_len/2, av_make_q(1, inlink->sample_rate), inlink->time_base);
875 s->frame_nsamples_max = FFMAX(s->frame_nsamples_max, frame->nb_samples);
876 return ff_filter_frame(ctx->outputs[0], frame);
879 static int request_frame(AVFilterLink *outlink)
881 AVFilterContext *ctx = outlink->src;
882 FIREqualizerContext *s= ctx->priv;
885 ret = ff_request_frame(ctx->inputs[0]);
886 if (ret == AVERROR_EOF && s->remaining > 0 && s->frame_nsamples_max > 0) {
887 AVFrame *frame = ff_get_audio_buffer(outlink, FFMIN(s->remaining, s->frame_nsamples_max));
890 return AVERROR(ENOMEM);
892 av_samples_set_silence(frame->extended_data, 0, frame->nb_samples, outlink->channels, frame->format);
893 frame->pts = s->next_pts;
894 s->remaining -= frame->nb_samples;
895 ret = filter_frame(ctx->inputs[0], frame);
901 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
902 char *res, int res_len, int flags)
904 FIREqualizerContext *s = ctx->priv;
905 int ret = AVERROR(ENOSYS);
907 if (!strcmp(cmd, "gain")) {
910 if (SELECT_GAIN(s) && !strcmp(SELECT_GAIN(s), args)) {
911 av_log(ctx, AV_LOG_DEBUG, "equal gain, do not rebuild.\n");
915 gain_cmd = av_strdup(args);
917 return AVERROR(ENOMEM);
919 ret = generate_kernel(ctx, gain_cmd, SELECT_GAIN_ENTRY(s));
921 av_freep(&s->gain_cmd);
922 s->gain_cmd = gain_cmd;
926 } else if (!strcmp(cmd, "gain_entry")) {
927 char *gain_entry_cmd;
929 if (SELECT_GAIN_ENTRY(s) && !strcmp(SELECT_GAIN_ENTRY(s), args)) {
930 av_log(ctx, AV_LOG_DEBUG, "equal gain_entry, do not rebuild.\n");
934 gain_entry_cmd = av_strdup(args);
936 return AVERROR(ENOMEM);
938 ret = generate_kernel(ctx, SELECT_GAIN(s), gain_entry_cmd);
940 av_freep(&s->gain_entry_cmd);
941 s->gain_entry_cmd = gain_entry_cmd;
943 av_freep(&gain_entry_cmd);
950 static const AVFilterPad firequalizer_inputs[] = {
953 .config_props = config_input,
954 .filter_frame = filter_frame,
955 .type = AVMEDIA_TYPE_AUDIO,
961 static const AVFilterPad firequalizer_outputs[] = {
964 .request_frame = request_frame,
965 .type = AVMEDIA_TYPE_AUDIO,
970 AVFilter ff_af_firequalizer = {
971 .name = "firequalizer",
972 .description = NULL_IF_CONFIG_SMALL("Finite Impulse Response Equalizer."),
974 .query_formats = query_formats,
975 .process_command = process_command,
976 .priv_size = sizeof(FIREqualizerContext),
977 .inputs = firequalizer_inputs,
978 .outputs = firequalizer_outputs,
979 .priv_class = &firequalizer_class,