WA Mother Wavelet and Scaling Function VI

Owning Palette: Filter Banks VIs

Requires: Advanced Signal Processing Toolkit

Computes the mother wavelet function and the scaling function from a filter bank.

Details  Example

	filters specifies the coefficients of the lowpass filters and the highpass filters to compute the mother wavelet and scaling functions. lowpass specifies the lowpass filter coefficients. highpass specifies the highpass filter coefficients.
	refinements specifies how many levels of lowpass filters to use to calculate the mother wavelet and scaling functions. refinements must be greater than or equal to 1.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	scaling function info returns the scaling function information this VI computes from the filter bank. t0 returns the offset to use when plotting the mother wavelet or scaling function. dt returns the multiplier, in samples, to use when plotting the mother wavelet or scaling function. scaling function returns the scaling function this VI computes from the filter bank.
	mother wavelet function info returns the mother wavelet function information this VI computes from the filter bank. t0 returns the offset to use when plotting the mother wavelet or scaling function. dt returns the multiplier, in samples, to use when plotting the mother wavelet or scaling function. wavelet function returns the mother wavelet function this VI computes from the filter bank.
	error out contains error information. This output provides standard error out functionality.

WA Mother Wavelet and Scaling Function Details

You can relate the mother wavelet function and the scaling function to the filter banks with the following equations:

where is the Fourier transform of the scaling function , is the Fourier transform of the mother wavelet function , is the corresponding lowpass filter, is the corresponding highpass filter, and h is refinements.

You can recover a precise approximation of and when refinements is large enough. Refer to A Wavelet Tour of Signal Processing for more information about the mother wavelet function and the scaling function.

Example

Refer to the Mother Wavelet and Scaling Function VI in the labview\examples\Wavelet Analysis\WAGettingStarted directory for an example of using the WA Mother Wavelet and Scaling Function VI.