不韋 呂 / Mbed 2 deprecated F746_SD_WavPlayer

Output the audio signal with filtering by IIR filter in the *.wav file on the SD card using onboard CODEC. SD カードの *.wav ファイルのオーディオ信号を遮断周波数可変の IIR フィルタを通して，ボードに搭載されているCODEC で出力する．

Dependencies:   BSP_DISCO_F746NG F746_GUI LCD_DISCO_F746NG SDFileSystem_Warning_Fixed TS_DISCO_F746NG mbed FrequencyResponseDrawer F746_SAI_IO Array_Matrix

MyClasses_Functions/IIR_CascadeFrqResp.hpp@11:769d986c10fa, 2016-07-04 (annotated)

Committer:
MikamiUitOpen
Date:
Mon Jul 04 05:59:44 2016 +0000
Revision:
11:769d986c10fa
Parent:
0:04b43b777fae 
12

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:04b43b777fae 1 //-----------------------------------------------------------
MikamiUitOpen 0:04b43b777fae 2 // Frequency response for IIR filter of cascade form
MikamiUitOpen 0:04b43b777fae 3 //
MikamiUitOpen 0:04b43b777fae 4 // 2016/04/16, Copyright (c) 2016 MIKAMI, Naoki
MikamiUitOpen 0:04b43b777fae 5 //-----------------------------------------------------------
MikamiUitOpen 0:04b43b777fae 6
MikamiUitOpen 0:04b43b777fae 7 #ifndef IIR_CASCADE_FREQUENCY_RESPONSE_HPP
MikamiUitOpen 0:04b43b777fae 8 #define IIR_CASCADE_FREQUENCY_RESPONSE_HPP
MikamiUitOpen 0:04b43b777fae 9
MikamiUitOpen 0:04b43b777fae 10 #include "FrequancyResponseBase.hpp"
MikamiUitOpen 0:04b43b777fae 11 #include "Biquad.hpp"
MikamiUitOpen 0:04b43b777fae 12
MikamiUitOpen 0:04b43b777fae 13 namespace Mikami
MikamiUitOpen 0:04b43b777fae 14 {
MikamiUitOpen 0:04b43b777fae 15 class IIR_CascadeFrqResp : public FrequencyResponse
MikamiUitOpen 0:04b43b777fae 16 {
MikamiUitOpen 0:04b43b777fae 17 public:
MikamiUitOpen 0:04b43b777fae 18 IIR_CascadeFrqResp() {}
MikamiUitOpen 0:04b43b777fae 19
MikamiUitOpen 0:04b43b777fae 20 // 次数とフィルタの係数設定
MikamiUitOpen 0:04b43b777fae 21 void SetParams(int order, float g0, Biquad::Coefs ck[])
MikamiUitOpen 0:04b43b777fae 22 {
MikamiUitOpen 0:04b43b777fae 23 order_ = order;
MikamiUitOpen 0:04b43b777fae 24 g0_ = g0;
MikamiUitOpen 0:04b43b777fae 25 ck_ = ck;
MikamiUitOpen 0:04b43b777fae 26 }
MikamiUitOpen 0:04b43b777fae 27
MikamiUitOpen 0:04b43b777fae 28 // 周波数応答の絶対値を返す関数, 引数: z^(-1)
MikamiUitOpen 0:04b43b777fae 29 virtual float AbsH_z(Complex u)
MikamiUitOpen 0:04b43b777fae 30 {
MikamiUitOpen 0:04b43b777fae 31 Complex h = g0_;
MikamiUitOpen 0:04b43b777fae 32 for (int k=0; k<order_/2; k++)
MikamiUitOpen 0:04b43b777fae 33 h = h*(1.0f + (ck_[k].b1 + ck_[k].b2*u)*u)
MikamiUitOpen 0:04b43b777fae 34 /((1.0f - (ck_[k].a1 + ck_[k].a2*u)*u));
MikamiUitOpen 0:04b43b777fae 35 return abs(h);
MikamiUitOpen 0:04b43b777fae 36 }
MikamiUitOpen 0:04b43b777fae 37
MikamiUitOpen 0:04b43b777fae 38 private:
MikamiUitOpen 0:04b43b777fae 39 int order_;
MikamiUitOpen 0:04b43b777fae 40 float g0_;
MikamiUitOpen 0:04b43b777fae 41 Biquad::Coefs *ck_;
MikamiUitOpen 0:04b43b777fae 42
MikamiUitOpen 0:04b43b777fae 43 // disallow copy constructor and assignment operator
MikamiUitOpen 0:04b43b777fae 44 IIR_CascadeFrqResp(const IIR_CascadeFrqResp&);
MikamiUitOpen 0:04b43b777fae 45 IIR_CascadeFrqResp& operator=(const IIR_CascadeFrqResp&);
MikamiUitOpen 0:04b43b777fae 46 };
MikamiUitOpen 0:04b43b777fae 47 }
MikamiUitOpen 0:04b43b777fae 48 #endif // IIR_CASCADE_FREQUENCY_RESPONSE_HPP