/
signal.clj
1049 lines (857 loc) · 37.5 KB
/
signal.clj
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
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
(ns fastmath.signal
"Signal processing (effect) and generation (oscillators).
Singal is any sequence with double values.
## Signal processing
To process signal use [[apply-effects]] or [[apply-effects-raw]] (operates on `double-array` only) function.
Effect is signal filter, created by [[effect]] multimethod. Effects can be composed with [[compose-effects]]. Effect can be treated as function and can be called for given sample.
Each effect has it's own parametrization which should be passed during creation.
List of all available effects is under [[effects-list]] value.
### Effects parametrization
Each effect has its own parameters.
#### :simple-lowpass, :simple-highpass
* `:rate` - sample rate (default 44100.0)
* `:cutoff` - cutoff frequency (default 2000.0)
#### :biquad-eq
Biquad equalizer
* `:fc` - center frequency
* `:gain` - gain
* `:bw` - bandwidth (default: 1.0)
* `:fs` - sampling rate (defatult: 44100.0)
#### :biquad-hs, :biquad-ls
Biquad highpass and lowpass shelf filters
* `:fc` - center frequency
* `:gain` - gain
* `:slope` - shelf slope (default 1.5)
* `:fs` - sampling rate (default 44100.0)
#### :biquad-lp, :biquad-hp, :biquad-bp
Biquad lowpass, highpass and bandpass filters
* `:fc` - cutoff/center frequency
* `:bw` - bandwidth (default 1.0)
* `:fs` - sampling rate (default 44100.0)
#### :dj-eq
* `:high` - high frequency gain (10000Hz)
* `:mid` - mid frequency gain (1000Hz)
* `:low` - low frequency gain (100Hz)
* `:shelf-slope` - shelf slope for high frequency (default 1.5)
* `:peak-bw` - peak bandwidth for mid and low frequencies (default 1.0)
* `:rate` - sampling rate (default 44100.0)
#### :phaser-allpass
* `:delay` - delay factor (default: 0.5)
#### :divider
* `:denom` (long, default 2.0)
#### :fm
Modulate and demodulate signal using frequency
* `:quant` - quantization value (0.0 - if no quantization, default 10)
* `:omega` - carrier factor (default 0.014)
* `:phase` - deviation factor (default 0.00822)
#### :bandwidth-limit
https://searchcode.com/file/18573523/cmt/src/lofi.cpp#
* `:rate` - sample rate (default 44100.0)
* `:freq` - cutoff frequency (default 1000.0)
#### :distort
* `:factor` - distortion factor (default 1.0)
#### :foverdrive
Fast overdrive
* `:drive` - drive (default 2.0)
#### :decimator
* `:bits` - bit depth (default 2)
* `:fs` - decimator sample rate (default 4410.0)
* `:rate` - input sample rate (default 44100.0)
#### :basstreble
* `:bass` - bass gain (default 1.0)
* `:treble` - treble gain (default 1.0)
* `:gain` - gain (default 0.0)
* `:rate` - sample rate (default 44100.0)
* `:slope` - slope for both (default 0.4)
* `:bass-freq` - bass freq (default 250.0)
* `:treble-freq` - treble freq (default 4000.0)
#### :echo
* `:delay` - delay time in seconds (default 0.5)
* `:decay` - decay (amount echo in signal, default 0.5)
* `:rate` - sample rate (default 44100.0)
_Warning! Echo filter uses mutable array as a internal state, don't use the same filter in paraller processing._
#### :vcf303
* `:rate` - sample rate (default 44100.0)
* `:trigger` - boolean, trigger some action (default `false`), set true when you reset filter every line
* `:cutoff` - cutoff frequency (values 0-1, default 0.8)
* `:resonance` - resonance (values 0-1, default 0.8)
* `:env-mod` - envelope modulation (values 0-1, default 0.5)
* `:decay` - decay (values 0-1, default 1.0)
* `:gain` - gain output signal (default: 1.0)
#### :slew-limit
http://git.drobilla.net/cgit.cgi/omins.lv2.git/tree/src/slew_limiter.c
* `:rate` - sample rate
* `:maxrise` - maximum change for rising signal (in terms of 1/rate steps, default 500)
* `:maxfall` - maximum change for falling singal (default 500)
#### :mda-thru-zero
* `:rate` - sample rate
* `:speed` - effect rate
* `:depth`
* `:mix`
* `:depth-mod`
* `:feedback`
_Warning: internal state is kept in doubles array._
## Oscillators
[[oscillator]] creates function which generates signal value for given time.
To sample generated wave to signal, call [[oscillator->signal]] with following parameters:
* `f` - oscillator
* `samplerate` - sample rate (samples per second)
* `seconds` - duration
To convert signal to oscillator (using interpolation) use [[signal->oscillator]] passing signal and duration.
Add oscillators using [[oscillators-sum]].
## Smoothing filter
Savitzky-Golay smoothing filter [[savgol-filter]].
## File operations
You can [[save-signal]] or [[load-signal]]. Representation is 16 bit signed, big endian. Use Audacity or SoX to convert to/from audio files."
(:require [fastmath.core :as m]
[clojure.java.io :refer [file make-parents output-stream input-stream]]
[fastmath.vector :as v]
[fastmath.random :as r]
[fastmath.interpolation :as i])
(:import [fastmath.vector Vec3]
[clojure.lang IFn]
[org.apache.commons.math3.linear Array2DRowRealMatrix SingularValueDecomposition]
[org.apache.commons.math3.util MathArrays]))
(set! *unchecked-math* :warn-on-boxed)
(m/use-primitive-operators)
;; ## Signal processing
;;
;; Looks like a fastest implementation (reduce and vector types are 8-10 times slower).
(declare single-pass)
(deftype SampleAndState [^double sample state]
Object
(toString [_] (str sample))) ; sample and effect state, StateWithF or vector of StateWithF
;; Type representing list node consisting resulting sample, effect functions, state value and link to next node (or nil if last node)
(deftype EffectsList [effect-name ^double sample effect state next]
Object
(toString [_] (str (if next
(str next " -> " (name effect-name))
(name effect-name)) " (" sample ")"))
IFn
(invoke [_] sample)
(invoke [e n]
(single-pass e n)))
(defn effect-node
"Create `EffectsList` node from effect function and initial state."
[effect-name f]
(EffectsList. effect-name 0.0 f (f) nil))
(defn- compose-two-effects
"Join two effect lists."
[^EffectsList e1 ^EffectsList e2]
(EffectsList. (.effect-name e1) (.sample e1) (.effect e1) (.state e1) (if (.next e1)
(compose-two-effects (.next e1) e2)
e2)))
(defn compose-effects
"Compose effects."
[^EffectsList e & es]
(reduce compose-two-effects e es))
(defn reset-effects
"Resets effects state to initial one."
[^EffectsList e]
(EffectsList. (.effect-name e) 0.0 (.effect e) ((.effect e)) (when (.next e)
(reset-effects (.next e)))))
(defn single-pass
"Process on sample using effects, returns `EffectsList` with result and new effect states."
[^EffectsList e ^double sample]
(if-not (.next e)
(let [^SampleAndState r ((.effect e) sample (.state e))]
(EffectsList. (.effect-name e) (.sample r) (.effect e) (.state r) nil))
(let [^EffectsList prev (single-pass (.next e) sample)
^SampleAndState r ((.effect e) (.sample prev) (.state e))]
(EffectsList. (.effect-name e) (.sample r) (.effect e) (.state r) prev))))
(defn apply-effects-raw
"Apply effects to signal as `double-array`.
If `reset` is positive, reinit state each `reset` number of samples.
Returns new signal as `double-array`."
(^doubles [^doubles in effects ^long reset]
(let [len (alength in)
^doubles out (double-array len)]
(loop [idx (int 0)
effects-and-state effects]
(when (< idx len)
(let [sample (aget in idx)
^EffectsList res (single-pass effects-and-state sample)
idx+ (inc idx)]
(aset out idx ^double (.sample res))
(recur idx+
(if (and (pos? reset) (zero? ^long (mod idx+ reset)))
(reset-effects effects)
res)))))
out))
(^doubles [^doubles in effects] (apply-effects-raw in effects 0)))
(defn apply-effects
"Apply effects to signal as any sequence.
If `reset` is positive, reinit state each `reset` number of samples.
Returns new signal."
([in effects ^long reset] (m/double-array->seq (apply-effects-raw (m/seq->double-array in) effects reset)))
([in effects] (apply-effects in effects 0)))
;; ## Helper functions
(defn db->linear
"DB to Linear"
^double [^double x]
(m/pow 10.0 (/ x 20.0)))
(defn linear->db
"Linear to DB"
^double [x]
(* 20.0 (m/log10 x)))
;; ## Effects / Filters
(defmulti effect
"Create effect for given name (as keyword) and optional parameters.
List of all possible effects is under [[effects-list]].
Effect is a custom type which contains: name, sample (result of last call), effect function and current state.
Effect can be considered as function: call with sample to effect with next state or call without parameter to obtain latest result. Effects are also composable with [[compose-effects]]."
(fn [m & _] m))
;; ### Simple Low/High pass filters
(defn- calc-filter-alpha
"Calculate alpha factor"
^double [^double rate ^double cutoff]
(let [tinterval (/ rate)
tau (/ (* cutoff m/TWO_PI))]
(/ tinterval (+ tau tinterval))))
(defmethod effect :simple-lowpass
([m] (effect m {}))
([m {:keys [rate cutoff]
:or {rate 44100.0 cutoff 2000.0}}]
(let [alpha (calc-filter-alpha rate cutoff)]
(effect-node m (fn
([^double sample ^double prev]
(let [s1 (* sample alpha)
s2 (- prev (* prev alpha))
nprev (+ s1 s2)]
(SampleAndState. nprev nprev)))
([] 0.0))))))
(defmethod effect :simple-highpass
([m] (effect m {}))
([m conf]
(let [lpfilter (effect :simple-lowpass conf)]
(effect-node m (fn
([^double sample lp]
(let [^EffectsList res (single-pass lp sample)]
(SampleAndState. (- sample (.sample res)) res)))
([] lpfilter))))))
;; ### Biquad filters
;; Store biquad effect configuration in `BiquadConf` type
(deftype BiquadConf [^double b0 ^double b1 ^double b2 ^double a1 ^double a2])
(defn- biquad-eq-params
"Calculate configuration for biquad equalizer
fc - center frequency
gain
bw - bandwidth
fs - sample rate"
[^double fc ^double gain ^double bw ^double fs]
(let [w (/ (* m/TWO_PI (m/constrain fc 1.0 (* 0.5 fs))) fs)
cw (m/cos w)
sw (m/sin w)
J (m/pow 10.0 (* gain 0.025))
g (-> bw
(m/constrain 0.0001 4.0)
(* m/LN2_2 w)
(/ sw)
(m/sinh)
(* sw))
a0r (/ (+ 1.0 (/ g J)))
b0 (* a0r (+ 1.0 (* g J)))
b1 (* a0r -2.0 cw)
b2 (* a0r (- 1.0 (* g J)))
a1 (- b1)
a2 (* a0r (- (/ g J) 1.0))]
(BiquadConf. b0 b1 b2 a1 a2)))
(defn- biquad-hs-params
"Calculate configuration for biquad high shelf
fc - center frequency
gain
slope - shelf slope
fs - sample rate"
[^double fc ^double gain ^double slope ^double fs]
(let [w (/ (* m/TWO_PI (m/constrain fc 1.0 (* 0.5 fs))) fs)
cw (m/cos w)
sw (m/sin w)
A (m/pow 10.0 (* gain 0.025))
iA (inc A)
dA (dec A)
b (m/sqrt (- (/ (inc (* A A)) (m/constrain slope 0.0001 1.0)) (* dA dA)))
apc (* cw iA)
amc (* cw dA)
bs (* b sw)
a0r (->> amc
(- iA)
(+ bs)
(/ 1.0))
b0 (* a0r A (+ iA amc bs))
b1 (* a0r A -2.0 (+ dA apc))
b2 (* a0r A (- (+ iA amc) bs))
a1 (* a0r -2.0 (- dA apc))
a2 (* a0r (+ (dec (- A)) amc bs))]
(BiquadConf. b0 b1 b2 a1 a2)))
(defn- biquad-ls-params
"Calculate configuration for biquad low shelf
fc - center frequency
gain
slope - shelf slope
fs - sample rate"
[^double fc ^double gain ^double slope ^double fs]
(let [w (/ (* m/TWO_PI (m/constrain fc 1.0 (* 0.5 fs))) fs)
cw (m/cos w)
sw (m/sin w)
A (m/pow 10.0 (* gain 0.025))
iA (inc A)
dA (dec A)
b (m/sqrt (- (/ (inc (* A A)) (m/constrain slope 0.0001 1.0)) (* dA dA)))
apc (* cw iA)
amc (* cw dA)
bs (* b sw)
a0r (->> amc
(+ iA)
(+ bs)
(/ 1.0))
b0 (* a0r A (- (+ iA bs) amc))
b1 (* a0r A 2.0 (- dA apc))
b2 (* a0r A (- iA amc bs))
a1 (* a0r 2.0 (+ dA apc))
a2 (* a0r (+ bs (- (dec (- A)) amc)))]
(BiquadConf. b0 b1 b2 a1 a2)))
(defn- biquad-lp-params
"Calculate configuration for biquad low pass"
[^double fc ^double bw ^double fs]
(let [omega (* m/TWO_PI (/ fc fs))
sn (m/sin omega)
cs (m/cos omega)
alpha (* sn (m/sinh (* m/LN2_2 bw (/ omega sn))))
a0r (/ (inc alpha))
cs- (- 1.0 cs)
b0 (* a0r 0.5 cs-)
b1 (* a0r cs-)
b2 b0
a1 (* a0r 2.0 cs)
a2 (* a0r (dec alpha))]
(BiquadConf. b0 b1 b2 a1 a2)))
(defn- biquad-hp-params
"Calculate configuration for biquad high pass"
[^double fc ^double bw ^double fs]
(let [omega (* m/TWO_PI (/ fc fs))
sn (m/sin omega)
cs (m/cos omega)
alpha (* sn (m/sinh (* m/LN2_2 bw (/ omega sn))))
a0r (/ (inc alpha))
cs+ (inc cs)
b0 (* a0r 0.5 cs+)
b1 (* a0r (- cs+))
b2 b0
a1 (* a0r 2.0 cs)
a2 (* a0r (dec alpha))]
(BiquadConf. b0 b1 b2 a1 a2)))
(defn- biquad-bp-params
"Calculate configuration for biquad band pass"
[^double fc ^double bw ^double fs]
(let [omega (* m/TWO_PI (/ fc fs))
sn (m/sin omega)
cs (m/cos omega)
alpha (if (zero? sn) 0.0 (* sn (m/sinh (* m/LN2_2 bw (/ omega sn)))))
a0r (/ (inc alpha))
b0 (* a0r alpha)
b1 0.0
b2 (* a0r (- alpha))
a1 (* a0r 2.0 cs)
a2 (* a0r (dec alpha))]
(BiquadConf. b0 b1 b2 a1 a2)))
;; Store state in `StateBiquad` type.
(deftype StateBiquad [^double x2 ^double x1 ^double y2 ^double y1])
(defn- make-biquad-filter
"Create biquad effect based on passed configuration"
[m ^BiquadConf c]
(effect-node m (fn
([^double sample ^StateBiquad state]
(let [y (-> (* (.b0 c) sample)
(+ (* (.b1 c) (.x1 state)))
(+ (* (.b2 c) (.x2 state)))
(+ (* (.a1 c) (.y1 state)))
(+ (* (.a2 c) (.y2 state))))]
(SampleAndState. y (StateBiquad. (.x1 state) sample (.y1 state) y))))
([] (StateBiquad. 0.0 0.0 0.0 0.0)))))
;; ### Biquad equalizer
(defmethod effect :biquad-eq
([m] (effect m {}))
([m {:keys [fc gain bw fs]
:or {fc 1000.0 gain 0.0 bw 1.0 fs 44100.0}}]
(make-biquad-filter m (biquad-eq-params fc gain bw fs))))
;; ### Biquad high/low shelf
(defmethod effect :biquad-hs
([m] (effect m {}))
([m {:keys [fc gain slope fs]
:or {fc 1000.0 gain 0.0 slope 1.5 fs 44100.0}}]
(make-biquad-filter m (biquad-hs-params fc gain slope fs))))
(defmethod effect :biquad-ls
([m] (effect m {}))
([m {:keys [fc gain slope fs]
:or {fc 1000.0 gain 0.0 slope 1.5 fs 44100.0}}]
(make-biquad-filter m (biquad-ls-params fc gain slope fs))))
;; ### Biquad lowpass/highpass/bandpass
(defn- lhb-params
"Create parameters for lp hp and bp biquad filters."
[f {:keys [fc bw fs]
:or {fc 1000.0 bw 1.0 fs 44100.0}}]
(f fc bw fs))
(defmethod effect :biquad-lp ([m] (effect m {})) ([m conf] (make-biquad-filter m (lhb-params biquad-lp-params conf))))
(defmethod effect :biquad-hp ([m] (effect m {})) ([m conf] (make-biquad-filter m (lhb-params biquad-hp-params conf))))
(defmethod effect :biquad-bp ([m] (effect m {})) ([m conf] (make-biquad-filter m (lhb-params biquad-bp-params conf))))
;; ### DJ Equalizer
(defmethod effect :dj-eq
([m] (effect m {}))
([m {:keys [hi mid low shelf-slope peak-bw ^double rate]
:or {hi 0.0 mid 0.0 low 0.0 shelf-slope 1.5 peak-bw 1.0 rate 44100.0}}]
(let [b (compose-effects
(effect :biquad-hs {:fc (* rate (/ 10000.0 44100.0)) :gain hi :slope shelf-slope :fs rate})
(effect :biquad-eq {:fc (* rate (/ 1000.0 44100.0)) :gain mid :bw peak-bw :fs rate})
(effect :biquad-eq {:fc (* rate (/ 100.0 44100.0)) :gain low :bw peak-bw :fs rate}))]
(effect-node m (fn
([sample state]
(let [^EffectsList res (single-pass state sample)]
(SampleAndState. (.sample res) res)))
([] b))))))
;; ### Phaser
(defmethod effect :phaser-allpass
([m] (effect m {}))
([m {:keys [^double delay]
:or {delay 0.5}}]
(let [a1 (/ (- 1.0 delay) (inc delay))]
(effect-node m (fn
([^double sample ^double zm1]
(let [y (+ zm1 (* sample (- a1)))
new-zm1 (+ sample (* y a1))]
(SampleAndState. y new-zm1)))
([] 0.0))))))
;; ### Divider
(deftype StateDivider [^double out ^double amp ^double count ^double lamp ^double last ^int zeroxs])
(defmethod effect :divider
([m] (effect m {}))
([m {:keys [^long denom]
:or {denom 2.0}}]
(effect-node m
(fn
([^double sample ^StateDivider state]
(let [count (inc (.count state))
^StateDivider s1 (if (or (and (> sample 0.0) (<= (.last state) 0.0))
(and (neg? sample) (>= (.last state) 0.0)))
(if (== denom 1)
(StateDivider. (if (pos? (.out state)) -1.0 1.0) 0.0 0.0 (/ (.amp state) count) (.last state) 0)
(StateDivider. (.out state) (.amp state) count (.lamp state) (.last state) (inc (.zeroxs state))))
(StateDivider. (.out state) (.amp state) count (.lamp state) (.last state) (.zeroxs state)))
amp (+ (.amp s1) (m/abs sample))
^StateDivider s2 (if (and (> denom 1)
(== ^long (rem (.zeroxs s1) denom) (dec denom)))
(StateDivider. (if (pos? (.out s1)) -1.0 1.0) 0.0 0 (/ amp (.count s1)) (.last s1) 0)
(StateDivider. (.out s1) amp (.count s1) (.lamp s1) (.last s1) (.zeroxs s1)))]
(SampleAndState. (* (.out s2) (.lamp s2)) (StateDivider. (.out s2) (.amp s2) (.count s2) (.lamp s2) sample (.zeroxs s2)))))
([] (StateDivider. 1.0 0.0 0.0 0.0 0.0 0.0))))))
;; ### FM filter
(deftype StateFm [^double pre ^double integral ^double t lp])
(defmethod effect :fm
([m] (effect m {}))
([m {:keys [^double quant ^double omega ^double phase]
:or {quant 10.0 omega 0.014 phase 0.00822}}]
(let [lp-chain (compose-effects (effect :simple-lowpass {:rate 100000 :cutoff 25000})
(effect :simple-lowpass {:rate 100000 :cutoff 10000})
(effect :simple-lowpass {:rate 100000 :cutoff 1000}))]
(effect-node m
(fn
([^double sample ^StateFm state]
(let [sig (* sample phase)
new-integral (+ (.integral state) sig)
m (m/cos (+ new-integral (* omega (.t state))))
m (if (pos? quant)
(m/norm (unchecked-int (m/norm m -1.0 1.0 0.0 quant)) 0.0 quant -1.0 1.0)
m)
dem (m/abs (- m (.pre state)))
^EffectsList res (single-pass (.lp state) dem)
demf (/ (* 2.0 (- (.sample res) omega)) phase)]
(SampleAndState. (m/constrain demf -1.0 1.0) (StateFm. m new-integral (inc (.t state)) res))))
([] (StateFm. 0.0 0.0 0.0 lp-chain)))))))
;; ### Bandwidth limit
(defmethod effect :bandwidth-limit
([m] (effect m {}))
([m {:keys [^double freq ^double rate]
:or {freq 1000.0 rate 44100.0}}]
(let [dx (/ freq rate)]
(effect-node m (fn
([^double sample ^double state]
(let [res (if (>= sample state)
(min (+ state dx) sample)
(max (- state dx) sample))]
(SampleAndState. res res)))
([] 0.0))))))
;; ### Distortion
(defmethod effect :distort
([m] (effect m {}))
([m {:keys [^double factor]
:or {factor 1.0}}]
(let [nfact (inc factor)]
(effect-node m (fn
([^double sample state]
(let [div (+ factor (m/abs sample))
res (* nfact (/ sample div))]
(SampleAndState. res state)))
([]))))))
;; ### Fast overdrive
(defmethod effect :foverdrive
([m] (effect m {}))
([m {:keys [^double drive]
:or {drive 2.0}}]
(let [drivem1 (dec drive)]
(effect-node m (fn
([^double sample state]
(let [fx (m/abs sample)
res (/ (* sample (+ fx drive)) (inc (+ (* sample sample) (* fx drivem1))))]
(SampleAndState. res state)))
([]))))))
;; ### Decimator
(deftype StateDecimator [^double count ^double last])
(defmethod effect :decimator
([m] (effect m {}))
([m {:keys [^double bits ^double fs ^double rate]
:or {bits 2.0 fs 4410.0 rate 44100.0}}]
(let [step (m/pow 0.5 (- bits 0.9999))
stepr (/ step)
ratio (/ fs rate)]
(effect-node m (fn
([^double sample ^StateDecimator state]
(let [ncount (+ (.count state) ratio)]
(if (>= ncount 1.0)
(let [delta (* step ^double (m/remainder (->> sample
m/sgn
(* step 0.5)
(+ sample)
(* stepr)) 1.0))
last (- sample delta)]
(SampleAndState. last (StateDecimator. (dec ncount) last)))
(SampleAndState. (.last state) (StateDecimator. ncount (.last state))))))
([] (StateDecimator. 0.0 0.0)))))))
;; ### BassTreble
(deftype StateBassTreble [^double xn1Bass ^double xn2Bass ^double yn1Bass ^double yn2Bass
^double xn1Treble ^double xn2Treble ^double yn1Treble ^double yn2Treble])
(defmethod effect :basstreble
([m] (effect m {}))
([m {:keys [^double bass ^double treble ^double gain ^double rate ^double slope ^double bass-freq ^double treble-freq]
:or {bass 1.0 treble 1.0 gain 0.0 rate 44100.0 slope 0.4 bass-freq 250.0 treble-freq 4000.0}}]
(let [data-gain (db->linear gain)
wb (/ (* m/TWO_PI bass-freq) rate)
wt (/ (* m/TWO_PI treble-freq) rate)
cwb (m/cos wb)
cwt (m/cos wt)
ab (m/exp (/ (* 2.302585092994046 bass) 40.0))
ab+ (inc ab)
ab- (dec ab)
at (m/exp (/ (* 2.302585092994046 treble) 40.0))
at+ (inc at)
at- (dec at)
bb (m/sqrt (- (/ (inc (m/sq ab)) slope) (m/sq (dec ab))))
bt (m/sqrt (- (/ (inc (m/sq at)) slope) (m/sq (dec at))))
bswb (* bb (m/sin wb))
bswt (* bt (m/sin wt))
b0b (* ab (+ (- ab+ (* ab- cwb)) bswb))
b1b (* 2.0 ab (- ab- (* ab+ cwb)))
b2b (* ab (- (- ab+ (* ab- cwb)) bswb))
a0b (+ (+ ab+ (* ab- cwb)) bswb)
a1b (* -2.0 (+ ab- (* ab+ cwb)))
a2b (- (+ ab+ (* ab- cwb)) bswb)
b0t (* at (+ (+ at+ (* at- cwt)) bswt))
b1t (* -2.0 at (+ at- (* at+ cwt)))
b2t (* at (- (+ at+ (* at- cwt)) bswt))
a0t (+ (- at+ (* at- cwt)) bswt)
a1t (* 2.0 (- at- (* at+ cwt)))
a2t (- (- at+ (* at- cwt)) bswt)]
(effect-node m (fn
([^double sample ^StateBassTreble state]
(let [outb (/ (-> (* b0b sample)
(+ (* b1b (.xn1Bass state)))
(+ (* b2b (.xn2Bass state)))
(- (* a1b (.yn1Bass state)))
(- (* a2b (.yn2Bass state)))) a0b)
outt (/ (-> (* b0t outb)
(+ (* b1t (.xn1Treble state)))
(+ (* b2t (.xn2Treble state)))
(- (* a1t (.yn1Treble state)))
(- (* a2t (.yn2Treble state)))) a0t)]
(SampleAndState. (* outt data-gain)
(StateBassTreble. sample (.xn1Bass state) outb (.yn1Bass state)
outb (.xn1Treble state) outt (.yn1Treble state)))))
([] (StateBassTreble. 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0)))))))
;; ### Echo (audacity)
(deftype StateEcho [^doubles buffer ^int position])
(defmethod effect :echo
([m] (effect m {}))
([m {:keys [^double delay ^double decay ^double rate]
:or {delay 0.5 decay 0.5 rate 44100.0}}]
(let [buffer-len (int (min 10000000 (* delay rate)))]
(effect-node m (fn
([^double sample ^StateEcho state]
(let [result (+ sample (* decay (aget ^doubles (.buffer state) (.position state))))]
(aset ^doubles (.buffer state) (.position state) result)
(SampleAndState. result (StateEcho. (.buffer state) (rem (inc (.position state)) buffer-len)))))
([]
(StateEcho. (double-array buffer-len 0.0) 0)))))))
;; ### Vcf303
;;
(deftype StateVcf303 [^double d1 ^double d2 ^double c0 ^int env-pos ^Vec3 abc])
(defmethod effect :vcf303
([m] (effect m {}))
([m {:keys [^double rate trigger ^double cutoff ^double resonance ^double env-mod ^double decay ^double gain]
:or {rate 44100.0 trigger false cutoff 0.8 resonance 0.8 env-mod 0.5 decay 1.0 gain 1.0}}]
(let [scale (/ m/PI rate)
e0 (* scale
(m/exp (-> (- 5.613 (* 0.8 env-mod))
(+ (* 2.1553 cutoff))
(- (* 0.7696 (- 1.0 resonance))))))
d (m/pow (->> decay
(* 2.3)
(+ 0.2)
(* rate)
(/ 1.0)
(m/pow 0.1)) 64.0)
r (m/exp (- (* 3.455 resonance) 1.20))
recalc-abc (fn [^double vc0]
(let [whopping (+ e0 vc0)
k (m/exp (/ (- whopping) r))
a (* (+ k k) (m/cos (+ whopping whopping)))
b (* (- k) k)
c (* 0.2 (- (- 1.0 a) b))]
(Vec3. a b c)))
init-c0 (if trigger
(- (* scale
(m/exp (-> (+ 6.109 (* 1.5876 env-mod))
(+ (* 2.1553 cutoff))
(- (* 1.2 (- 1.0 resonance)))))) e0)
0.0)]
(effect-node m (fn
([^double sample ^StateVcf303 state]
(let [^Vec3 abc (.abc state)
result (-> (* (.x abc) (.d1 state))
(+ (* (.y abc) (.d2 state)))
(+ (* (.z abc) sample)))
d2 (.d1 state)
d1 result
env-pos (inc (.env-pos state))]
(if (>= env-pos 64)
(let [c0 (* d (.c0 state))]
(SampleAndState. (* gain result)
(StateVcf303. d1 d2 c0 0 (recalc-abc c0))))
(SampleAndState. (* gain result)
(StateVcf303. d1 d2 (.c0 state) env-pos abc)))))
([] (StateVcf303. 0.0 0.0 init-c0 0 (recalc-abc init-c0))))))))
;; ### Slew limiter
(defmethod effect :slew-limit
([m] (effect m {}))
([m {:keys [^double rate ^double maxrise ^double maxfall]
:or {rate 44100.0 maxrise 500.0 maxfall 500.0}}]
(let [maxinc (/ maxrise rate)
maxdec (- (/ maxfall rate))]
(effect-node m (fn
([^double sample ^double prev]
(let [increment (- sample prev)
nsample (+ prev (m/constrain increment maxdec maxinc))]
(SampleAndState. nsample nsample)))
([] 0.0))))))
;;
(deftype StateMdaThruZero [^doubles buffer ^double ph ^long bp ^double f])
(defmethod effect :mda-thru-zero
([m] (effect m {}))
([m {:keys [^double rate ^double speed ^double depth ^double mix ^double depth-mod ^double feedback]
:or {rate 44100.0 speed 0.3 depth 0.43 mix 0.47 feedback 0.3 depth-mod 1.0}}]
(let [rat (/ (* (m/pow 10.0 (- 2.0 (* 3.0 speed))) 2.0) rate)
dep (* 2000.0 (m/sq depth))
dem (- dep (* dep depth-mod))
dep (- dep dem)
wet mix
dry (- 1.0 wet)
fb (- (* 1.9 feedback) 0.95)]
(effect-node m (fn
([^double sample ^StateMdaThruZero state]
(let [ph (+ (.ph state) rat)
ph (if (> ph 1.0) (- ph 2.0) ph)
bp (bit-and (dec (.bp state)) 0x7ff)]
(aset ^doubles (.buffer state) bp (+ sample (* fb (.f state))))
(let [tmpf (+ dem (* dep (- 1.0 (m/sq ph))))
tmp (unchecked-int tmpf)
tmpf (- tmpf tmp)
tmp (bit-and (+ tmp bp) 0x7ff)
tmpi (bit-and (inc tmp) 0x7ff)
f (aget ^doubles (.buffer state) tmp)
f (+ (* tmpf (- (aget ^doubles (.buffer state) tmpi) f)) f)
result (+ (* sample dry) (* f wet))]
(SampleAndState. result (StateMdaThruZero. (.buffer state) ph bp f)))))
([] (StateMdaThruZero. (double-array 2048) 0.0 0 0.0)))))))
(def ^{:doc "List of effects."}
effects-list (sort (keys (methods effect))))
;; ## File operations
(defn save-signal
"Save signal to file.
Representation is: 16 bit signed, big endian file
You can use Audacity/SOX utilities to convert files to audio."
[sig filename]
(make-parents filename)
(let [^java.io.DataOutputStream out (java.io.DataOutputStream. (output-stream filename))
s (m/seq->double-array sig)]
(try
(dotimes [i (alength s)]
(.writeShort out (short (m/cnorm (aget s i) -1.0 1.0 Short/MIN_VALUE Short/MAX_VALUE))))
(.flush out)
(finally (. out clojure.core/close)))
s))
(defn load-signal
"Read signal from file
Expected representation is 16 bit signed, big endian file."
[filename]
(let [^java.io.File f (file filename)
len (/ (.length f) 2)
^java.io.DataInputStream in (java.io.DataInputStream. (input-stream filename))
^doubles buffer (double-array len)]
(try
(dotimes [i len]
(aset ^doubles buffer (int i) (double (m/cnorm (.readShort in) Short/MIN_VALUE Short/MAX_VALUE -1.0 1.0))))
(finally (. in clojure.core/close)))
buffer))
;; ## Signal generators
;;
;; Here you have defined multimethods to create waves from various oscilators
;;
;; Parameters are:
;;
;; * oscilator name (see `oscillators` variable)
;; * frequency
;; * amplitude
;; * phase (0-1)
;;
;; Multimethod creates oscillator function accepting `double` (time) and resulting `double` from [-1.0 1.0] range.
(defmulti oscillator
"Create oscillator.
Parameters are:
* oscilator name (see `oscillators` variable)
* frequency
* amplitude
* phase (0-1)
Multimethod creates oscillator function accepting `double` (as time) and returns `double` from [-1.0 1.0] range.
To convert `oscillator` to signal, call [[signal-from-oscillator]].
To add oscillators, call [[sum-oscillators]]."
(fn [f _ _ _] f))
(defmethod oscillator :sin [_ ^double f ^double a ^double p]
(fn ^double [^double x]
(* a
(m/sin (+ (* p m/TWO_PI) (* x m/TWO_PI f))))))
(def ^:private snoise (r/fbm-noise {:noise-type :simplex
:octaves 1
:normalize? false}))
(defmethod oscillator :noise [_ ^double f ^double a ^double p]
(fn ^double [^double x]
(* a ^double (snoise (* (+ p x) f) 1.23456789))))
(defmethod oscillator :saw [_ ^double f ^double a ^double p]
(fn ^double [^double x]
(let [rp (* 2.0 a)
p2 (* f (mod (+ (* a p) a x) 1.0))]
(* rp (- p2 (m/floor p2) 0.5)))))
(defmethod oscillator :square [_ ^double f ^double a ^double p]
(fn ^double [^double x]
(if (< (mod (+ p (* x f)) 1.0) 0.5)
a
(- a))))
(defmethod oscillator :triangle [_ ^double f ^double a ^double p]
(let [saw (oscillator :saw f a p)]
(fn ^double [^double x]
(- (* 2.0 (m/abs (saw x))) a))))
(defmethod oscillator :cut-triangle [_ ^double f ^double a ^double p]
(let [tri (oscillator :triangle f a p)]
(fn ^double [^double x]
(let [namp (* 0.5 a)]
(* 2.0 (m/constrain ^double (tri x) (- namp) namp))))))
(defmethod oscillator :constant [_ _ ^double a _] (constantly a))
(def ^{:doc "List of oscillator names used with [[oscillator]]"}
oscillators (sort (keys (methods oscillator))))
(defn oscillators-sum
"Create oscillator which is sum of all oscillators."
[& fs]
(reduce #(fn ^double [^double x] (+ ^double (%1 x) ^double (%2 x))) fs))
(defn oscillator-gain
[fs ^double gain]
(fn ^double [^double x]
(* gain ^double (fs x))))
(defn oscillator->signal
"Create signal from oscillator.
Parameters are:
* f - oscillator
* samplerate - in Hz
* seconds - duration
Returns sampled signal as double array."
[f ^double samplerate ^double seconds]
(let [len (* samplerate seconds)
^doubles buffer (double-array len)]
(dotimes [i len]
(aset ^doubles buffer i (m/constrain ^double (f (m/norm i 0 len 0 seconds)) -1.0 1.0)))
buffer))
(defn signal->oscillator
"Create oscillator from signal.
Parameters:
* sig - signal as sequence
* seconds - duration
* interpolator - interpolation (see [[fastmath.interpolation]]). Default: [[linear-smile]]."
([sig ^double seconds] (signal->oscillator sig seconds i/linear-smile))
([sig ^double seconds interpolator]
(let [c (count sig)
step (/ seconds c)]
(interpolator (for [^long i (range c)]
(* i step)) sig))))
;; signal smoothing
(defn- perform-convolution
[coeffs fc signal]
(->> (MathArrays/convolve (m/seq->double-array signal) coeffs)
(drop fc)
(take (count signal))))
(defn savgol-filter
"Creates Savitzky-Golay smoothing filter.
Arguments:
* length - length of the kernel (default: 5)
* order - polynomial order (default: 2)
* derivative - signal derivative (default: 0)
Returns filtering function which accepts collection of numbers and returns filtered signal."
([] (savgol-filter 5))
([^long length] (savgol-filter length 2))
([^long length ^long order] (savgol-filter length order 0))