File: Reverb.cc

package info (click to toggle)
caps 0.9.26-1
  • links: PTS, VCS
  • area: main
  • in suites: buster, sid
  • size: 924 kB
  • sloc: cpp: 10,867; ansic: 1,324; makefile: 78; python: 38
file content (416 lines) | stat: -rw-r--r-- 9,634 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
/*
	Reverb.cc
	
	Copyright 2002-16 Tim Goetze <tim@quitte.de>
	
	http://quitte.de/dsp/

	Three reverb units: JVRev, Plate and PlateX2.
	
	The former is a rewrite of STK's JVRev, a traditional design.
	
	Original comment:
	
		This is based on some of the famous    
		Stanford CCRMA reverbs (NRev, KipRev)  
		all based on the Chowning/Moorer/      
		Schroeder reverberators, which use     
		networks of simple allpass and comb    
		delay filters.  

	The algorithm is mostly unchanged in this implementation; the delay
	line lengths have been fiddled with to make the stereo field more
	evenly weighted, denormal protection and a bandwidth control have been 
	added as well.

	The latter two are based on the circuit discussed in Jon Dattorro's 
	September 1997 JAES paper on effect design (part 1: reverb & filters).
*/
/*
	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License
	as published by the Free Software Foundation; either version 3
	of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
	02111-1307, USA or point your web browser to http://www.gnu.org.
*/

#include "basics.h"

#include "Reverb.h"
#include "Descriptor.h"

int JVRev_length[9] = { 4199, 4999, 5399, 5801, 1051, 337, 113, 573, 487 };

void
JVRev::init()
{
	double s = fs/44100.;

	for(int i = 0; i < 9; ++i)
	{
		int v = (int) (s * JVRev_length[i]);
		v |= 1;
		while(!DSP::isprime(v))
			v += 2;
		length[i] = v;
	}
	
	for(int i = 0; i < 4; ++i)
		comb[i].init(length[i]);

	for(int i = 0; i < 3; ++i)
		allpass[i].init(length[i+4]);

	left.init(length[7]);
	right.init(length[8]);

	/* such a simple number, yet I couldn't find a better one. */
	apc = .7;
}

void
JVRev::set_t60 (sample_t t)
{
	t60 = t;

	t = max(.00001, t);
	t = -3/(t*fs);

	for(int i=0; i<4; ++i)
		comb[i].c = pow(10, t*length[i]);
}

void
JVRev::activate()
{
	bandwidth.reset();
	tone.reset();

	for(int i=0; i<3; ++i)
		allpass[i].reset();
	
	for(int i=0; i<4; ++i)
		comb[i].reset();

	left.reset();
	right.reset();

	set_t60(getport(1));
	tone.set_f(1800*over_fs);
}

void
JVRev::cycle(uint frames)
{
	sample_t bw = .005 + .994*getport(0);
	bandwidth.set(exp(-M_PI*(1. - bw)));

	if(t60 != *ports[1])
		set_t60(getport(1));

	double wet = getport(2);
	wet = .38*wet*wet;
	double dry = 1 - wet;
	
	sample_t * s = ports[3];

	sample_t * dl = ports[4];
	sample_t * dr = ports[5];

	for(uint i = 0; i < frames; ++i)
	{
		sample_t x = s[i], a = x + normal;

		a = bandwidth.process(a);
		x *= dry;

		/* diffusors */
		a = allpass[0].process(a,-apc);
		a = allpass[1].process(a,-apc);
		a = allpass[2].process(a,-apc);

		/* tank */
		sample_t t = 0;
		a -= normal;

		for(int j=0; j<4; ++j)
			t += comb[j].process(a);

		t = tone.process(t);

		dl[i] = x + wet*left.putget(t);
		dr[i] = x + wet*right.putget(t);
	}
}

/* //////////////////////////////////////////////////////////////////////// */

PortInfo
JVRev::port_info [] =
{
	{ "bandwidth", INPUT | CONTROL, {DEFAULT_MID, 0, 1} }, 
	{ "t60 (s)", INPUT | CONTROL | GROUP, {DEFAULT_MID, 0, 5.6} }, 
	{ "blend", INPUT | CONTROL, {DEFAULT_LOW, 0, 1} }, 

	{ "in", INPUT | AUDIO }, 
	{ "out.l", OUTPUT | AUDIO }, 
	{ "out.r", OUTPUT | AUDIO }
};

template <> void
Descriptor<JVRev>::setup()
{
	Label = "JVRev";
	Name = CAPS "JVRev - Stanford-style reverb from STK";
	autogen();
}

/* //////////////////////////////////////////////////////////////////////// */

void
PlateStub::init()
{
	f_lfo = -1; 
	
#	define L(i) ((int) (l[i] * fs))
	static float l[] = {
		0.004771345048889486, 0.0035953092974026408, 
		0.01273478713752898, 0.0093074829474816042, 
		0.022579886428547427, 0.030509727495715868, 
		0.14962534861059779, 0.060481838647894894, 0.12499579987231611, 
		0.14169550754342933, 0.089244313027116023, 0.10628003091293972
	};

	/* lh */
	input.lattice[0].init(L(0));
	input.lattice[1].init(L(1));
	
	/* rh */
	input.lattice[2].init(L(2));
	input.lattice[3].init(L(3));

	/* modulated, width about 12 samples @ 44.1 */
	tank.mlattice[0].init(L(4), (int) (0.000403221 * fs));
	tank.mlattice[1].init(L(5), (int) (0.000403221 * fs));

	/* lh */
	tank.delay[0].init(L(6));
	tank.lattice[0].init(L(7));
	tank.delay[1].init(L(8));

	/* rh */
	tank.delay[2].init(L(9));
	tank.lattice[1].init(L(10));
	tank.delay[3].init(L(11));
#	undef L

#	define T(i) ((int) (t[i] * fs))
	static float t[] = {
		0.0089378717113000241, 0.099929437854910791, 0.064278754074123853, 
		0.067067638856221232, 0.066866032727394914, 0.006283391015086859, 
		0.01186116057928161, 0.12187090487550822, 0.041262054366452743, 
		0.089815530392123921, 0.070931756325392295, 0.011256342192802662
	};

	for(int i = 0; i < 12; ++i)
		tank.taps[i] = T(i);
#	undef T
	
	/* tuned for soft attack, ambience */
	indiff1 = .742;
	indiff2 = .712;

	dediff1 = .723;
	dediff2 = .729;
}

inline void
PlateStub::process(sample_t x, sample_t decay, sample_t * _xl, sample_t * _xr)
{
	x = input.bandwidth.process(x);
	
	/* lh */
	x = input.lattice[0].process(x, indiff1);
	x = input.lattice[1].process(x, indiff1);
	
	/* rh */
	x = input.lattice[2].process(x, indiff2);
	x = input.lattice[3].process(x, indiff2);

	/* summation point */
	register double xl = x + decay*tank.delay[3].get();
	register double xr = x + decay*tank.delay[1].get();

	/* lh */
	xl = tank.mlattice[0].process(xl, dediff1);
	xl = tank.delay[0].putget(xl);
	xl = tank.damping[0].process(xl);
	xl *= decay;
	xl = tank.lattice[0].process(xl, dediff2);
	tank.delay[1].put(xl);

	/* rh */
	xr = tank.mlattice[1].process(xr, dediff1);
	xr = tank.delay[2].putget(xr);
	xr = tank.damping[1].process(xr);
	xr *= decay;
	xr = tank.lattice[1].process(xr, dediff2);
	tank.delay[3].put(xr);

	/* gather output */
	xl  = .6 * tank.delay[2] [tank.taps[0]];
	xl += .6 * tank.delay[2] [tank.taps[1]];
	xl -= .6 * tank.lattice[1] [tank.taps[2]];
	xl += .6 * tank.delay[3] [tank.taps[3]];
	xl -= .6 * tank.delay[0] [tank.taps[4]];
	xl += .6 * tank.lattice[0] [tank.taps[5]];

	xr  = .6 * tank.delay[0] [tank.taps[6]];
	xr += .6 * tank.delay[0] [tank.taps[7]];
	xr -= .6 * tank.lattice[0] [tank.taps[8]];
	xr += .6 * tank.delay[1] [tank.taps[9]];
	xr -= .6 * tank.delay[2] [tank.taps[10]];
	xr += .6 * tank.lattice[1] [tank.taps[11]];

	*_xl = xl;
	*_xr = xr;
}

/* //////////////////////////////////////////////////////////////////////// */

void
Plate::cycle(uint frames)
{
	sample_t bw = .005 + .994*getport(0);
	input.bandwidth.set(exp (-M_PI * (1. - bw)));

	sample_t decay = .749*getport(1);

	double damp = exp(-M_PI * (.0005+.9995*getport(2)));
	tank.damping[0].set(damp);
	tank.damping[1].set(damp);

	sample_t blend = getport(3);
	blend = pow(blend, 1.6); /* linear is not a good choice for this pot */
	sample_t dry = 1 - blend;

	sample_t * s = ports[4];

	sample_t * dl = ports[5];
	sample_t * dr = ports[6];

	/* modulated lattice interpolation needs float truncation */
	DSP::FPTruncateMode _truncate;

	for(uint i = 0; i < frames; ++i)
	{
		normal = -normal;
		sample_t x = s[i] + normal;

		sample_t xl, xr;

		PlateStub::process(x, decay, &xl, &xr);

		x = dry * s[i];

		dl[i] = x + blend*xl;
		dr[i] = x + blend*xr;
	}
}

/* //////////////////////////////////////////////////////////////////////// */

PortInfo
Plate::port_info [] =
{
	{"bandwidth", INPUT | CONTROL, {DEFAULT_MID, 0, 1} }, 
	{"tail", INPUT | CONTROL | GROUP, {DEFAULT_HIGH, 0, 1} }, 
	{"damping", INPUT | CONTROL, {DEFAULT_MID, 0, 1} }, 
	{"blend", INPUT | CONTROL | GROUP, {DEFAULT_LOW, 0, 1} }, 

	{"in", INPUT | AUDIO},
	{"out.l", OUTPUT | AUDIO}, 
	{"out.r",	OUTPUT | AUDIO}
};

template <> void
Descriptor<Plate>::setup()
{
	Label = "Plate";
	Name = CAPS "Plate - Versatile plate reverb";
	autogen();
}

/* //////////////////////////////////////////////////////////////////////// */

void
PlateX2::cycle(uint frames)
{
	sample_t bw = .005 + .994*getport(0);
	input.bandwidth.set(exp (-M_PI * (1. - bw)));

	sample_t decay = .749*getport(1);

	double damp = exp(-M_PI * (.0005+.9995*getport(2)));
	tank.damping[0].set(damp);
	tank.damping[1].set(damp);

	sample_t blend = getport(3);
	blend = pow(blend, 1.53); 
	sample_t dry = 1 - blend;

	sample_t * sl = ports[4];
	sample_t * sr = ports[5];
	sample_t * dl = ports[6];
	sample_t * dr = ports[7];

	/* the modulated lattices interpolate, which needs truncated float */
	DSP::FPTruncateMode _truncate;

	for(uint i = 0; i < frames; ++i)
	{
		normal = -normal;
		sample_t x = (sl[i] + sr[i] + normal) * .5;

		sample_t xl, xr;
		PlateStub::process(x, decay, &xl, &xr);

		dl[i] = blend*xl + dry*sl[i];
		dr[i] = blend*xr + dry*sr[i];
	}
}

/* //////////////////////////////////////////////////////////////////////// */

PortInfo
PlateX2::port_info [] =
{
	{"bandwidth", INPUT | CONTROL, {DEFAULT_MID, 0, 1} /* .9995 */ }, 
	{"tail", INPUT | CONTROL | GROUP, {DEFAULT_MID, 0, 1} /* .5 */ }, 
	{"damping", INPUT | CONTROL, {DEFAULT_HIGH, 0, 1} /* .0005 */ }, 
	{"blend", INPUT | CONTROL | GROUP, {DEFAULT_LOW, 0, 1} }, 

	{"in.l", INPUT | AUDIO},
	{"in.r", INPUT | AUDIO},
	{"out.l", OUTPUT | AUDIO}, 
	{"out.r",	OUTPUT | AUDIO}
};

template <> void
Descriptor<PlateX2>::setup()
{
	Label = "PlateX2";
	Name = CAPS "PlateX2 - Versatile plate reverb, stereo inputs";
	autogen();
}