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IIR_CascadeFrqResp.hpp@0:cacfc9e25452, 2019-06-04 (annotated)
- Committer:
- phungductung
- Date:
- Tue Jun 04 21:58:08 2019 +0000
- Revision:
- 0:cacfc9e25452
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Who changed what in which revision?
User | Revision | Line number | New contents of line |
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phungductung | 0:cacfc9e25452 | 1 | //----------------------------------------------------------- |
phungductung | 0:cacfc9e25452 | 2 | // Frequency response for IIR filter of cascade form |
phungductung | 0:cacfc9e25452 | 3 | // |
phungductung | 0:cacfc9e25452 | 4 | // 2016/04/16, Copyright (c) 2016 MIKAMI, Naoki |
phungductung | 0:cacfc9e25452 | 5 | //----------------------------------------------------------- |
phungductung | 0:cacfc9e25452 | 6 | |
phungductung | 0:cacfc9e25452 | 7 | #ifndef IIR_CASCADE_FREQUENCY_RESPONSE_HPP |
phungductung | 0:cacfc9e25452 | 8 | #define IIR_CASCADE_FREQUENCY_RESPONSE_HPP |
phungductung | 0:cacfc9e25452 | 9 | |
phungductung | 0:cacfc9e25452 | 10 | #include "FrequancyResponseBase.hpp" |
phungductung | 0:cacfc9e25452 | 11 | #include "Biquad.hpp" |
phungductung | 0:cacfc9e25452 | 12 | |
phungductung | 0:cacfc9e25452 | 13 | namespace Mikami |
phungductung | 0:cacfc9e25452 | 14 | { |
phungductung | 0:cacfc9e25452 | 15 | class IIR_CascadeFrqResp : public FrequencyResponse |
phungductung | 0:cacfc9e25452 | 16 | { |
phungductung | 0:cacfc9e25452 | 17 | public: |
phungductung | 0:cacfc9e25452 | 18 | IIR_CascadeFrqResp() {} |
phungductung | 0:cacfc9e25452 | 19 | |
phungductung | 0:cacfc9e25452 | 20 | // 次数とフィルタの係数設定 |
phungductung | 0:cacfc9e25452 | 21 | void SetParams(int order, float g0, Biquad::Coefs ck[]) |
phungductung | 0:cacfc9e25452 | 22 | { |
phungductung | 0:cacfc9e25452 | 23 | order_ = order; |
phungductung | 0:cacfc9e25452 | 24 | g0_ = g0; |
phungductung | 0:cacfc9e25452 | 25 | ck_ = ck; |
phungductung | 0:cacfc9e25452 | 26 | } |
phungductung | 0:cacfc9e25452 | 27 | |
phungductung | 0:cacfc9e25452 | 28 | // 周波数応答の絶対値を返す関数, 引数: z^(-1) |
phungductung | 0:cacfc9e25452 | 29 | virtual float AbsH_z(Complex u) |
phungductung | 0:cacfc9e25452 | 30 | { |
phungductung | 0:cacfc9e25452 | 31 | Complex h = g0_; |
phungductung | 0:cacfc9e25452 | 32 | for (int k=0; k<order_/2; k++) |
phungductung | 0:cacfc9e25452 | 33 | h = h*(1.0f + (ck_[k].b1 + ck_[k].b2*u)*u) |
phungductung | 0:cacfc9e25452 | 34 | /((1.0f - (ck_[k].a1 + ck_[k].a2*u)*u)); |
phungductung | 0:cacfc9e25452 | 35 | return abs(h); |
phungductung | 0:cacfc9e25452 | 36 | } |
phungductung | 0:cacfc9e25452 | 37 | |
phungductung | 0:cacfc9e25452 | 38 | private: |
phungductung | 0:cacfc9e25452 | 39 | int order_; |
phungductung | 0:cacfc9e25452 | 40 | float g0_; |
phungductung | 0:cacfc9e25452 | 41 | Biquad::Coefs *ck_; |
phungductung | 0:cacfc9e25452 | 42 | |
phungductung | 0:cacfc9e25452 | 43 | // disallow copy constructor and assignment operator |
phungductung | 0:cacfc9e25452 | 44 | IIR_CascadeFrqResp(const IIR_CascadeFrqResp&); |
phungductung | 0:cacfc9e25452 | 45 | IIR_CascadeFrqResp& operator=(const IIR_CascadeFrqResp&); |
phungductung | 0:cacfc9e25452 | 46 | }; |
phungductung | 0:cacfc9e25452 | 47 | } |
phungductung | 0:cacfc9e25452 | 48 | #endif // IIR_CASCADE_FREQUENCY_RESPONSE_HPP |