Output the audio signal (*.bin) with filtering by IIR filter in the SD card using onboard CODEC. For *.wav file, F746_SD_WavPlayer and F746_SD_GraphicEqualiser are published on mbed. SD カードのオーディオ信号 (*.bin) 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.*.wav 形式のファイル用には,F746_SD_WavPlayer と F746_SD_GraphicEqualiser を mbed で公開している.
Dependencies: BSP_DISCO_F746NG_patch_fixed F746_GUI LCD_DISCO_F746NG SDFileSystem_Warning_Fixed TS_DISCO_F746NG mbed
MyClasses_Functions/BilinearDesignLH.hpp@5:4a99dabc9180, 2016-04-17 (annotated)
- Committer:
- MikamiUitOpen
- Date:
- Sun Apr 17 08:44:43 2016 +0000
- Revision:
- 5:4a99dabc9180
- Parent:
- 0:6748e3332e85
6
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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MikamiUitOpen | 0:6748e3332e85 | 1 | //------------------------------------------------------------------------------ |
MikamiUitOpen | 0:6748e3332e85 | 2 | // Design of Butterworth LPF and HPF using bilinear transform -- Header |
MikamiUitOpen | 0:6748e3332e85 | 3 | // |
MikamiUitOpen | 0:6748e3332e85 | 4 | // 2016/03/31, Copyright (c) 2016 MIKAMI, Naoki |
MikamiUitOpen | 0:6748e3332e85 | 5 | //------------------------------------------------------------------------------ |
MikamiUitOpen | 0:6748e3332e85 | 6 | |
MikamiUitOpen | 0:6748e3332e85 | 7 | #ifndef BILINEAR_BUTTERWORTH_HPP |
MikamiUitOpen | 0:6748e3332e85 | 8 | #define BILINEAR_BUTTERWORTH_HPP |
MikamiUitOpen | 0:6748e3332e85 | 9 | |
MikamiUitOpen | 0:6748e3332e85 | 10 | #include "mbed.h" |
MikamiUitOpen | 0:6748e3332e85 | 11 | #include <complex> // requisite |
MikamiUitOpen | 0:6748e3332e85 | 12 | |
MikamiUitOpen | 0:6748e3332e85 | 13 | namespace Mikami |
MikamiUitOpen | 0:6748e3332e85 | 14 | { |
MikamiUitOpen | 0:6748e3332e85 | 15 | typedef complex<float> Complex; // define "Complex" |
MikamiUitOpen | 0:6748e3332e85 | 16 | |
MikamiUitOpen | 0:6748e3332e85 | 17 | class BilinearDesign |
MikamiUitOpen | 0:6748e3332e85 | 18 | { |
MikamiUitOpen | 0:6748e3332e85 | 19 | public: |
MikamiUitOpen | 0:6748e3332e85 | 20 | struct Coefs { float a1, a2, b1, b2; }; |
MikamiUitOpen | 0:6748e3332e85 | 21 | enum Type { LPF, HPF }; |
MikamiUitOpen | 0:6748e3332e85 | 22 | |
MikamiUitOpen | 0:6748e3332e85 | 23 | // Constructor |
MikamiUitOpen | 0:6748e3332e85 | 24 | BilinearDesign(int order, float fs) |
MikamiUitOpen | 0:6748e3332e85 | 25 | : PI_FS_(PI_/fs), ORDER_(order) |
MikamiUitOpen | 0:6748e3332e85 | 26 | { |
MikamiUitOpen | 0:6748e3332e85 | 27 | sP_ = new Complex[order/2]; |
MikamiUitOpen | 0:6748e3332e85 | 28 | zP_ = new Complex[order/2]; |
MikamiUitOpen | 0:6748e3332e85 | 29 | ck_ = new Coefs[order/2]; |
MikamiUitOpen | 0:6748e3332e85 | 30 | } |
MikamiUitOpen | 0:6748e3332e85 | 31 | |
MikamiUitOpen | 0:6748e3332e85 | 32 | // Destractor |
MikamiUitOpen | 0:6748e3332e85 | 33 | ~BilinearDesign() |
MikamiUitOpen | 0:6748e3332e85 | 34 | { |
MikamiUitOpen | 0:6748e3332e85 | 35 | delete[] sP_; |
MikamiUitOpen | 0:6748e3332e85 | 36 | delete[] zP_; |
MikamiUitOpen | 0:6748e3332e85 | 37 | delete[] ck_; |
MikamiUitOpen | 0:6748e3332e85 | 38 | } |
MikamiUitOpen | 0:6748e3332e85 | 39 | |
MikamiUitOpen | 0:6748e3332e85 | 40 | // Execution of design |
MikamiUitOpen | 0:6748e3332e85 | 41 | void Execute(float fc, Type pb, Coefs c[], float& g); |
MikamiUitOpen | 0:6748e3332e85 | 42 | |
MikamiUitOpen | 0:6748e3332e85 | 43 | private: |
MikamiUitOpen | 0:6748e3332e85 | 44 | static const float PI_ = 3.1415926536f; |
MikamiUitOpen | 0:6748e3332e85 | 45 | const float PI_FS_; |
MikamiUitOpen | 0:6748e3332e85 | 46 | const int ORDER_; |
MikamiUitOpen | 0:6748e3332e85 | 47 | |
MikamiUitOpen | 0:6748e3332e85 | 48 | Complex* sP_; // Poles on s-plane |
MikamiUitOpen | 0:6748e3332e85 | 49 | Complex* zP_; // Poles on z-plane |
MikamiUitOpen | 0:6748e3332e85 | 50 | Coefs* ck_; // Coefficients of transfer function for cascade form |
MikamiUitOpen | 0:6748e3332e85 | 51 | float gain_; // Gain factor for cascade form |
MikamiUitOpen | 0:6748e3332e85 | 52 | |
MikamiUitOpen | 0:6748e3332e85 | 53 | void Butterworth(); |
MikamiUitOpen | 0:6748e3332e85 | 54 | void Bilinear(float fc); |
MikamiUitOpen | 0:6748e3332e85 | 55 | void ToCascade(Type pb); |
MikamiUitOpen | 0:6748e3332e85 | 56 | void GetGain(Type pb); |
MikamiUitOpen | 0:6748e3332e85 | 57 | void GetCoefs(Coefs c[], float& gain); |
MikamiUitOpen | 0:6748e3332e85 | 58 | }; |
MikamiUitOpen | 0:6748e3332e85 | 59 | } |
MikamiUitOpen | 0:6748e3332e85 | 60 | #endif // BILINEAR_BUTTERWORTH_HPP |