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TutorialBiquad - Tutorial

Overview

Multichannel Biquad filter

Discussion

Standard 5 coefficient Biquad filter that operates on multichannel data. The module uses a Transposed Direct Form 2 implementation using the difference equation:

wN = a1*wNm1 + a2*wNm2 + x[n] y[n] = b0*wN + b1*wNm1 + b2*wNm2 wNm2 = wNm1 wNm1 = wN

This module is an example to be used with the documentation.

Type Definition

typedef struct _ModuleTutorialBiquad

{

    ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure

    FLOAT32 b0;                                   // First numerator coefficient

    FLOAT32 b1;                                   // Second numerator coefficient

    FLOAT32 b2;                                   // Third numerator coefficient

    FLOAT32 a1;                                   // Second denominator coefficient

    FLOAT32 a2;                                   // Third denominator coefficient

    FLOAT32* state;                               // State variables. 2 per channel.

} ModuleTutorialBiquadClass;

Variables

Properties

Name

Type

Usage

isHidden

Default value

Range

Units

b0

float

parameter

0

1

Unrestricted

b1

float

parameter

0

0

Unrestricted

b2

float

parameter

0

0

Unrestricted

a1

float

parameter

0

0

Unrestricted

a2

float

parameter

0

0

Unrestricted

state

float*

state

1

[2 x 1]

Unrestricted

Pins

Input Pins

                Name: in

         Description: Input signal

           Data type: float

       Channel range: Unrestricted

    Block size range: Unrestricted

   Sample rate range: Unrestricted

     Complex support: Real

Output Pins

                Name: out

         Description: Output signal

           Data type: float

MATLAB Usage

File Name: tutorial_biquad_module.m

 M = tutorial_biquad_module(NAME)

 Example showing how to implement a multichannel Biquad filter in Audio Weaver.

 Arguments:

    NAME - name of the module.

Return to tutorial_module

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