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Owning Palette: Discrete Wavelet VIs

Installed With: Advanced Signal Processing Toolkit

Computes the multi-level inverse discrete wavelet transform (DWT) and returns the reconstructed signal from the approximation coefficients and the detail coefficients. An interpolator with a factor 2 and the lowpass synthesis filters and the highpass synthesis filters implement the inverse discrete wavelet transform at each level. Wire data to 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 Inverse 1D Discrete Wavelet Transform (waveform)WA Inverse 1D Discrete Wavelet Transform (array)WA Inverse 2D Discrete Wavelet Transform

WA Inverse 1D Discrete Wavelet Transform (waveform)

	DWT coef specifies the approximation coefficients and the detail coefficients for the multi-level inverse discrete wavelet transform. You must organize the coefficients into a waveform starting with the approximation coefficients at the largest level followed by the detail coefficients at all levels in descending order.
	length specifies the length of the approximation coefficients, the detail coefficients, and the signal. You must organize length into a 1D array starting with the length of the approximation coefficients at the largest level, the length of the detail coefficients at all levels in descending order, and the length of the signal.
	wavelet specifies the wavelet type of the discrete wavelet analysis. The default is db02. wavelet must be the same type as the wavelet type you selected in the WA Discrete Wavelet Transform VI to compute DWT coef. If you used the analysis filters input of the WA Discrete Wavelet Transform VI to specify wavelet, ignore this input and use the synthesis filters input of this VI to specify the synthesis filters of the wavelet.
	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 for the wavelet you specify. If you specify a value for synthesis filters, the VI ignores the settings in the wavelet input. 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.
	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 Inverse 1D Discrete Wavelet Transform (array)

	DWT coef specifies the approximation coefficients and the detail coefficients for the multi-level inverse discrete wavelet decomposition. You must organize the coefficients into a 1D real array starting with the approximation coefficients at the largest level followed by the detail coefficients at all levels in descending order.
	length specifies the length of the approximation coefficients, the detail coefficients, and the signal. You must organize length into a 1D array starting with the length of the approximation coefficients at the largest level, the length of the detail coefficients at all levels in descending order, and the length of the signal.
	wavelet specifies the wavelet type of the discrete wavelet analysis. The default is db02. wavelet must be the same type as the wavelet type you selected in the WA Discrete Wavelet Transform VI to compute DWT coef. If you used the analysis filters input of the WA Discrete Wavelet Transform VI to specify wavelet, ignore this input and use the synthesis filters input of this VI to specify the synthesis filters of the wavelet.
	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 for the wavelet you specify. If you specify a value for synthesis filters, the VI ignores the settings in the wavelet input. 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.
	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 Inverse 2D Discrete Wavelet Transform

	size specifies the size of the reconstructed 2D signal as the number of rows followed by the number of columns.
	DWT coef specifies the approximation coefficients and the detail coefficients for the multi-level inverse discrete wavelet transform. Each element of the array contains the 2D DWT results of one level. The ith element stores the approximation coefficients and the detail coefficients at level i+1. 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.
	wavelet specifies the wavelet type of the discrete wavelet analysis. The default is db02. wavelet must be the same type as the wavelet type you selected in the WA Discrete Wavelet Transform VI to compute DWT coef. If you used the analysis filters input of the WA Discrete Wavelet Transform VI to specify wavelet, ignore this input and use the synthesis filters input of this VI to specify the synthesis filters of the wavelet.
	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 for the wavelet you specify. If you specify a value for synthesis filters, the VI ignores the settings in the wavelet input. 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.
	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 Inverse Discrete Wavelet Transform VI:

• ECG Compression VI: labview\examples\Wavelet Analysis\WAApplications.llb
• Image Compression VI: labview\examples\Wavelet Analysis\WAApplications.llb
• Get and Set Single Level Detail Coefficients VI: labview\examples\Wavelet Analysis\WAGettingStarted.llb
• Wavelet Transform and Reconstruction with Image VI: labview\examples\Wavelet Analysis\WAGettingStarted.llb
• Piece Polynomial Function Approx and Comp VI: labview\examples\Wavelet Analysis\WAGettingStarted.llb