(8.D.2.1) 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 | Â |
postShift | int | derived | 1 | 1 | Unrestricted | Â |
coeffs | float* | parameter | 0 | [31 x 1] | Unrestricted | Â |
coeffsfract32 | fract32* | derived | 0 | [32 x 1] | Unrestricted | Â |
state | fract32* | state | 1 | [68 x 1] | Unrestricted | Â |
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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