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(8.D.2.4) FIRFract32

Overview

FIR fract32 filter

Discussion

The FIR Fract32 Module implements a direct convolution N-order Finite Impulse Response filter. The module operates on multiple channels with all channels sharing the same set of filter coefficients. coeffs holds the filter coefficients and is of size numTaps x 1. The coefficients are stored in coeffs in normal order. The state variable array is of size numTaps*numChannels.

Type Definition

typedef struct _ModuleFIRFract32 { ModuleInstanceDescriptor instance; // Common Audio Weaver module instance structure INT32 numTaps; // Length of the filter INT32 stateIndex; // Index of the oldest state variable in the array of state variables INT32 postShift; // Number of bits to shift FLOAT32* coeffs; // Coefficient array fract32* coeffsfract32; // Coefficient array fract32* state; // State variable array } ModuleFIRFract32Class;

Variables

Properties

Name

Type

Usage

isHidden

Default value

Range

Units

numTaps

int

const

0

31

1:1:5000

samples

stateIndex

int

state

1

0

Unrestricted

 

postShift

int

derived

1

1

Unrestricted

 

coeffs

float*

parameter

0

[31 x 1]

Unrestricted

 

coeffsfract32

fract32*

derived

0

[32 x 1]

Unrestricted

 

state

fract32*

state

1

[68 x 1]

Unrestricted

 

Pins

Input Pins

Name: in

Description: audio input

Data type: fract32

Channel range: Unrestricted

Block size range: Unrestricted

Sample rate range: Unrestricted

Complex support: Real

Output Pins

Name: out

Description: audio output

Data type: fract32

MATLAB Usage

File Name: fir_fract32_module.m

M=fir_fract32_module(NAME, L) Creates an FIR filter object for use in the Audio Weaver environment. The module has a single multi-channel input pin. Arguments: NAME - name of the module. L - length of the filter (number of taps).

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