|
andrewm@0
|
1 //
|
|
andrewm@0
|
2 // Biquad.h
|
|
andrewm@0
|
3 //
|
|
andrewm@0
|
4 // Created by Nigel Redmon on 11/24/12
|
|
andrewm@0
|
5 // EarLevel Engineering: earlevel.com
|
|
andrewm@0
|
6 // Copyright 2012 Nigel Redmon
|
|
andrewm@0
|
7 //
|
|
andrewm@0
|
8 // For a complete explanation of the Biquad code:
|
|
andrewm@0
|
9 // http://www.earlevel.com/main/2012/11/25/biquad-c-source-code/
|
|
andrewm@0
|
10 //
|
|
andrewm@0
|
11 // License:
|
|
andrewm@0
|
12 //
|
|
andrewm@0
|
13 // This source code is provided as is, without warranty.
|
|
andrewm@0
|
14 // You may copy and distribute verbatim copies of this document.
|
|
andrewm@0
|
15 // You may modify and use this source code to create binary code
|
|
andrewm@0
|
16 // for your own purposes, free or commercial.
|
|
andrewm@0
|
17 //
|
|
andrewm@0
|
18
|
|
andrewm@0
|
19 #ifndef Biquad_h
|
|
andrewm@0
|
20 #define Biquad_h
|
|
andrewm@0
|
21
|
|
andrewm@0
|
22 enum {
|
|
andrewm@0
|
23 bq_type_lowpass = 0,
|
|
andrewm@0
|
24 bq_type_highpass,
|
|
andrewm@0
|
25 bq_type_bandpass,
|
|
andrewm@0
|
26 bq_type_notch,
|
|
andrewm@0
|
27 bq_type_peak,
|
|
andrewm@0
|
28 bq_type_lowshelf,
|
|
andrewm@0
|
29 bq_type_highshelf
|
|
andrewm@0
|
30 };
|
|
andrewm@0
|
31
|
|
andrewm@0
|
32 class Biquad {
|
|
andrewm@0
|
33 public:
|
|
andrewm@0
|
34 Biquad();
|
|
andrewm@0
|
35 Biquad(int type, double Fc, double Q, double peakGainDB);
|
|
andrewm@0
|
36 ~Biquad();
|
|
andrewm@0
|
37 void setType(int type);
|
|
andrewm@0
|
38 void setQ(double Q);
|
|
andrewm@0
|
39 void setFc(double Fc);
|
|
andrewm@0
|
40 void setPeakGain(double peakGainDB);
|
|
andrewm@0
|
41 void setBiquad(int type, double Fc, double Q, double peakGain);
|
|
andrewm@0
|
42 float process(float in);
|
|
andrewm@0
|
43
|
|
andrewm@0
|
44 double getQ();
|
|
andrewm@0
|
45 double getFc();
|
|
andrewm@0
|
46 double getPeakGain();
|
|
andrewm@0
|
47
|
|
andrewm@0
|
48 double getStartingQ();
|
|
andrewm@0
|
49 double getStartingFc();
|
|
andrewm@0
|
50 double getStartingPeakGain();
|
|
andrewm@0
|
51
|
|
andrewm@0
|
52 protected:
|
|
andrewm@0
|
53 void calcBiquad(void);
|
|
andrewm@0
|
54
|
|
andrewm@0
|
55 int type;
|
|
andrewm@0
|
56 double a0, a1, a2, b1, b2;
|
|
andrewm@0
|
57 double Fc, Q, peakGain;
|
|
andrewm@0
|
58 double startFc, startQ, startPeakGain;
|
|
andrewm@0
|
59 double z1, z2;
|
|
andrewm@0
|
60 };
|
|
andrewm@0
|
61
|
|
andrewm@0
|
62 inline double Biquad::getQ()
|
|
andrewm@0
|
63 {
|
|
andrewm@0
|
64 return Q;
|
|
andrewm@0
|
65 }
|
|
andrewm@0
|
66
|
|
andrewm@0
|
67 inline double Biquad::getFc()
|
|
andrewm@0
|
68 {
|
|
andrewm@0
|
69 return Fc;
|
|
andrewm@0
|
70 }
|
|
andrewm@0
|
71
|
|
andrewm@0
|
72 inline double Biquad::getPeakGain()
|
|
andrewm@0
|
73 {
|
|
andrewm@0
|
74 return peakGain;
|
|
andrewm@0
|
75 }
|
|
andrewm@0
|
76
|
|
andrewm@0
|
77 inline double Biquad::getStartingQ()
|
|
andrewm@0
|
78 {
|
|
andrewm@0
|
79 return startQ;
|
|
andrewm@0
|
80 }
|
|
andrewm@0
|
81
|
|
andrewm@0
|
82 inline double Biquad::getStartingFc()
|
|
andrewm@0
|
83 {
|
|
andrewm@0
|
84 return startFc;
|
|
andrewm@0
|
85 }
|
|
andrewm@0
|
86
|
|
andrewm@0
|
87 inline double Biquad::getStartingPeakGain()
|
|
andrewm@0
|
88 {
|
|
andrewm@0
|
89 return startPeakGain;
|
|
andrewm@0
|
90 }
|
|
andrewm@0
|
91
|
|
andrewm@0
|
92 inline float Biquad::process(float in) {
|
|
andrewm@0
|
93 double out = in * a0 + z1;
|
|
andrewm@0
|
94 z1 = in * a1 + z2 - b1 * out;
|
|
andrewm@0
|
95 z2 = in * a2 - b2 * out;
|
|
andrewm@0
|
96 return out;
|
|
andrewm@0
|
97 }
|
|
andrewm@0
|
98
|
|
andrewm@0
|
99 #endif // Biquad_h
|
