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Owning Palette: Filter Banks VIs

Installed With: Advanced Signal Processing Toolkit

Computes the single-level inverse discrete wavelet transform using a two-channel synthesis filter bank. This VI reconstructs the original signal with the low-frequency subband (approx coef) and the high-frequency subband (detail coef). Wire data to the approx coef or the DWT coef input to determine the polymorphic instance to use or manually select the instance.

Examples

Use the pull-down menu to select an instance of this VI.

Select an instance WA 1D Synthesis Filter Bank (waveform)WA 1D Synthesis Filter Bank (array)WA 2D Synthesis Filter Bank

WA 1D Synthesis Filter Bank (waveform)

	approx coef specifies the approximation coefficients.
	detail coef specifies the detail coefficients.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters. You can use the WA Wavelet Filter VI to obtain the filters of commonly used wavelets. You can use the Wavelet Design Express VI to design the analysis filters and the corresponding synthesis filters. lowpass specifies the coefficients of the lowpass synthesis filter, which the VI uses to filter the interpolated approximation coefficients in the wavelet reconstruction. highpass specifies the coefficients of the highpass synthesis filter, which the VI uses to filter the interpolated detail coefficients in the wavelet reconstruction.
	shift specifies how many zeroes to pad at the beginning of the approximation coefficients and the detail coefficients before interpolation filtering. shift must be the same value as the value you used in the WA Analysis Filter Bank VI to compute approx coef and detail coef or DWT coef.
	signal contains the reconstructed signal.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

WA 1D Synthesis Filter Bank (array)

	approx coef specifies the approximation coefficients.
	detail coef specifies the detail coefficients.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters. You can use the WA Wavelet Filter VI to obtain the filters of commonly used wavelets. You can use the Wavelet Design Express VI to design the analysis filters and the corresponding synthesis filters. lowpass specifies the coefficients of the lowpass synthesis filter, which the VI uses to filter the interpolated approximation coefficients in the wavelet reconstruction. highpass specifies the coefficients of the highpass synthesis filter, which the VI uses to filter the interpolated detail coefficients in the wavelet reconstruction.
	shift specifies how many zeroes to pad at the beginning of the approximation coefficients and the detail coefficients before interpolation filtering. shift must be the same value as the value you used in the WA Analysis Filter Bank VI to compute approx coef and detail coef or DWT coef.
	signal contains the reconstructed signal.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

WA 2D Synthesis Filter Bank

	size specifies the dimensional size of the reconstructed 2D signal. The first and second elements of size contain the number of rows and the number of columns of the reconstructed 2D signal.
	DWT coef specifies the approximation coefficients and the detail coefficients for the 2D single-level inverse discrete wavelet transform. low_low specifies the approximation coefficients from the lowpass analysis filtering on each row and each column. The low_low coefficients are a low-resolution approximation of the original 2D signal. low_high specifies the detail coefficients from the lowpass analysis filtering on each row and the highpass analysis filtering on each column. The high-frequency signal along the column direction influences the low_high coefficients. high_low specifies the detail coefficients from the highpass analysis filtering on each row and the lowpass analysis filtering on each column. The high-frequency signal along the row direction influences the high_low coefficients. high_high specifies the detail coefficients from the highpass analysis filtering on each row and each column. The high-frequency signal along the diagonal direction influences the high_high coefficients.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters. You can use the WA Wavelet Filter VI to obtain the filters of commonly used wavelets. You can use the Wavelet Design Express VI to design the analysis filters and the corresponding synthesis filters. lowpass specifies the coefficients of the lowpass synthesis filter, which the VI uses to filter the interpolated approximation coefficients in the wavelet reconstruction. highpass specifies the coefficients of the highpass synthesis filter, which the VI uses to filter the interpolated detail coefficients in the wavelet reconstruction.
	shift specifies how many zeroes to pad at the beginning of the approximation coefficients and the detail coefficients before interpolation filtering. shift must be the same value as the value you used in the WA Analysis Filter Bank VI to compute approx coef and detail coef or DWT coef.
	signal contains the reconstructed signal.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

Examples

Refer to the following VIs for examples of using the WA Synthesis Filter Bank VI:

• Filter Banks - 1D VI: labview\examples\Wavelet Analysis\WAGettingStarted.llb
• Filter Banks - 2D VI: labview\examples\Wavelet Analysis\WAGettingStarted.llb