Overview
Sample-by-sample polynomial nonlinearity
Discussion
Polynomial nonlinearity, computed on a sample by sample basis. The module implements the following equation:
$y[n]=x[n]^{N-1}c[0]+x[n]^{N-2}c[1]+...+x[n]c[N-2] + c[N-1]$
where y is the output, x is the input, and c is the array of polynomial coefficients.
Type Definition
typedef struct _ModulePolynomialFract32
{
ModuleInstanceDescriptor instance; // Common Audio Weaver module instance structure
INT32 numCoeffs; // Number of coefficients in the polynomial
INT32 postShift; // Number of bits to shift
FLOAT32* coeffs; // Coefficient array in descending order. X^(N-1)*C[0] + X^(N-2)*C[1]+ ...
fract32* coeffsFract32; // Coefficient array in descending order. X^(N-1)*C[0] + X^(N-2)*C[1]+ ...
} ModulePolynomialFract32Class;
Variables
Properties
Name | Type | Usage | isHidden | Default value | Range | Units |
numCoeffs | int | const | 0 | 3 | Unrestricted | |
postShift | int | derived | 1 | 1 | Unrestricted | |
coeffs | float* | parameter | 0 | [3 x 1] | Unrestricted | |
coeffsFract32 | fract32* | derived | 0 | [3 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: polynomial_fract32_module.m
M=polynomial_fract32_module(NAME, NUMCOEFFS)
Creates a sample-by-sample polynomial nonlinearity for us in the Audio
Weaver environment. The module has a single multi-channel input pin.
Arguments:
NAME - name of the module.
NUMCOEFFS - number of coefficients in the polynomial.
The order of the polynomial (the highest power of x) is NUMCOEFFS-1.
The polynomial coefficients use the same ordering as the MATLAB
polyval function.