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thresholds settings specifies the settings for the thresholding approximation coefficients and detail coefficients from the wavelet decomposition.
 |
thresholding rule specifies the threshold selection rules. If you specify a value for user defined thresholds, the VI ignores the settings in thresholding rule.
| 0 | SURE (default)—Uses the principle of Stein's Unbiased Risk Estimate (SURE) to estimate the threshold. | | 1 | Hybrid—Finds a compromise between the SURE method and the Universal method. When the signal-to-noise ratio of the noisy signal is very low, the VI uses the Universal method to estimate the threshold. | | 2 | Universal—Sets the threshold to sqrt(2×log(Ls)), where Ls is the signal length. | | 3 | Minimax—Uses the minimax principle to estimate the threshold. |
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rescaling method specifies the method to use to estimate the noise variance at each level. The default is single level. The VI uses the noise variance to rescale the threshold. Therefore, you can update the thresholds with the noise variance. If you specify a value for user defined thresholds, the VI ignores the settings in rescaling method.
| 0 | one—Specifies that the noise is white with unit variance. | | 1 | single level—Specifies that the noise is white. The VI estimates the noise standard deviation from the wavelet coefficients at the first level. | | 2 | multiple levels—Specifies that the noise does not have to be white. The VI estimates the noise standard deviation at each level independently. |
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soft threshold? specifies to use the soft thresholding method. The default is TRUE, which indicates that the VI uses the soft thresholding method. If soft threshold? is FALSE, the VI uses the hard thresholding method.
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option for approx coef specifies the operation for the approximation coefficients from the wavelet decomposition. The default is none. If you specify a value for user defined thresholds, the VI ignores the settings in option for approx coef.
| 0 | none—Does not change the approximation coefficients. | | 1 | threshold—Applies the same thresholding operation to the approximation coefficients. | | 2 | detrend—Sets the approximation coefficients to 0. |
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signal specifies the input signal.
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levels specifies the number of levels in the discrete wavelet analysis. levels must be a positive integer no greater than log2(Ls), where Ls is the length of the 1D signal or the minimum dimensional size of the 2D signal. The default is –1, which indicates that the VI sets levels as the largest integer no greater than log2(Ls).
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wavelet specifies the wavelet type to use for the discrete wavelet analysis. The default is db02. The options include two types: orthogonal (Haar, Daubechies (dbxx), Coiflets (coifx), Symmlets (symx)) and biorthogonal (FBI, Biorthogonal (biorx_x)), where x indicates the order of the wavelet.
The higher the order, the smoother the wavelet. The orthogonal wavelets are not redundant and are suitable for signal or image denoising and compression. The biorthogonal wavelets usually have the linear phase property and are suitable for signal or image feature extraction. If you want to use other types of wavelets, do not wire this input. Instead, use the Wavelet Design Express VI to design the wavelet you want, bundle the resulting analysis and synthesis filters, and then wire them to the filter banks input.
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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.
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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.
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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.
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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.
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filter banks specifies the analysis filter banks and the synthesis filter banks for the wavelet you specify. If you specify a value for filter banks, 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.
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analysis filters specifies the coefficients of the lowpass analysis filters and the highpass analysis filters for the wavelet you specify.
 |
lowpass specifies the coefficients of the lowpass analysis filter, which the VI uses to compute the approximation coefficients.
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highpass specifies the coefficients of the highpass analysis filter, which the VI uses to compute the detail coefficients.
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synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters for the wavelet you specify.
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lowpass specifies the coefficients of the lowpass synthesis filter, which the VI uses to filter the interpolated approximation coefficients in the wavelet reconstruction.
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highpass specifies the coefficients of the highpass synthesis filter, which the VI uses to filter the interpolated detail coefficients in the wavelet reconstruction.
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user defined thresholds specifies thresholds you define to rescale the wavelet coefficients. The length of user defined thresholds must equal levels. The first element of user defined thresholds contains the threshold for the detail coefficients at the largest level, and the last element of user defined thresholds contains the threshold for the detail coefficients at the first level. If you specify a value for user defined thresholds, the VI keeps the approximation coefficients unchanged and ignores the settings in thresholding rule, rescaling method, and option for approx coef.
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denoised signal contains the signal after denoising.
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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.
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status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
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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.
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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.
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thresholds settings specifies the settings for the thresholding approximation coefficients and detail coefficients from the wavelet decomposition.
|
thresholding rule specifies the threshold selection rules. If you specify a value for user defined thresholds, the VI ignores the settings in thresholding rule.
| 0 | SURE (default)—Uses the principle of Stein's Unbiased Risk Estimate (SURE) to estimate the threshold. | | 1 | Hybrid—Finds a compromise between the SURE method and the Universal method. When the signal-to-noise ratio of the noisy signal is very low, the VI uses the Universal method to estimate the threshold. | | 2 | Universal—Sets the threshold to sqrt(2×log(Ls)), where Ls is the signal length. | | 3 | Minimax—Uses the minimax principle to estimate the threshold. |
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rescaling method specifies the method to use to estimate the noise variance at each level. The default is single level. The VI uses the noise variance to rescale the threshold. Therefore, you can update the thresholds with the noise variance. If you specify a value for user defined thresholds, the VI ignores the settings in rescaling method.
| 0 | one—Specifies that the noise is white with unit variance. | | 1 | single level—Specifies that the noise is white. The VI estimates the noise standard deviation from the wavelet coefficients at the first level. | | 2 | multiple levels—Specifies that the noise does not have to be white. The VI estimates the noise standard deviation at each level independently. |
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soft threshold? specifies to use the soft thresholding method. The default is TRUE, which indicates that the VI uses the soft thresholding method. If soft threshold? is FALSE, the VI uses the hard thresholding method.
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option for approx coef specifies the operation for the approximation coefficients from the wavelet decomposition. The default is none. If you specify a value for user defined thresholds, the VI ignores the settings in option for approx coef.
| 0 | none—Does not change the approximation coefficients. | | 1 | threshold—Applies the same thresholding operation to the approximation coefficients. | | 2 | detrend—Sets the approximation coefficients to 0. |
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signal specifies the input signal.
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levels specifies the number of levels in the discrete wavelet analysis. levels must be a positive integer no greater than log2(Ls), where Ls is the length of the 1D signal or the minimum dimensional size of the 2D signal. The default is –1, which indicates that the VI sets levels as the largest integer no greater than log2(Ls).
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wavelet specifies the wavelet type to use for the discrete wavelet analysis. The default is db02. The options include two types: orthogonal (Haar, Daubechies (dbxx), Coiflets (coifx), Symmlets (symx)) and biorthogonal (FBI, Biorthogonal (biorx_x)), where x indicates the order of the wavelet.
The higher the order, the smoother the wavelet. The orthogonal wavelets are not redundant and are suitable for signal or image denoising and compression. The biorthogonal wavelets usually have the linear phase property and are suitable for signal or image feature extraction. If you want to use other types of wavelets, do not wire this input. Instead, use the Wavelet Design Express VI to design the wavelet you want, bundle the resulting analysis and synthesis filters, and then wire them to the filter banks input.
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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.
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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.
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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.
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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.
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filter banks specifies the analysis filter banks and the synthesis filter banks for the wavelet you specify. If you specify a value for filter banks, 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.
|
analysis filters specifies the coefficients of the lowpass analysis filters and the highpass analysis filters for the wavelet you specify.
|
lowpass specifies the coefficients of the lowpass analysis filter, which the VI uses to compute the approximation coefficients.
|
|
highpass specifies the coefficients of the highpass analysis filter, which the VI uses to compute the detail coefficients.
|
|
|
synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters for the wavelet you specify.
|
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.
|
|
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user defined thresholds specifies thresholds you define to rescale the wavelet coefficients. The length of user defined thresholds must equal levels. The first element of user defined thresholds contains the threshold for the detail coefficients at the largest level, and the last element of user defined thresholds contains the threshold for the detail coefficients at the first level. If you specify a value for user defined thresholds, the VI keeps the approximation coefficients unchanged and ignores the settings in thresholding rule, rescaling method, and option for approx coef.
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denoised signal contains the signal after denoising.
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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.
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status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
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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.
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|
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.
|
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|
thresholds settings specifies the settings for the thresholding approximation coefficients and detail coefficients from the wavelet decomposition.
|
thresholding rule specifies the threshold selection rules. If you specify a value for user defined thresholds, the VI ignores the settings in thresholding rule.
| 0 | SURE (default)—Uses the principle of Stein's Unbiased Risk Estimate (SURE) to estimate the threshold. | | 1 | Hybrid—Finds a compromise between the SURE method and the Universal method. When the signal-to-noise ratio of the noisy signal is very low, the VI uses the Universal method to estimate the threshold. | | 2 | Universal—Sets the threshold to sqrt(2×log(Ls)), where Ls is the signal length. | | 3 | Minimax—Uses the minimax principle to estimate the threshold. |
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rescaling method specifies the method to use to estimate the noise variance at each level. The default is single level. The VI uses the noise variance to rescale the threshold. Therefore, you can update the thresholds with the noise variance. If you specify a value for user defined thresholds, the VI ignores the settings in rescaling method.
| 0 | one—Specifies that the noise is white with unit variance. | | 1 | single level—Specifies that the noise is white. The VI estimates the noise standard deviation from the wavelet coefficients at the first level. | | 2 | multiple levels—Specifies that the noise does not have to be white. The VI estimates the noise standard deviation at each level independently. |
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soft threshold? specifies to use the soft thresholding method. The default is TRUE, which indicates that the VI uses the soft thresholding method. If soft threshold? is FALSE, the VI uses the hard thresholding method.
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option for approx coef specifies the operation for the approximation coefficients from the wavelet decomposition. The default is none. If you specify a value for user defined thresholds, the VI ignores the settings in option for approx coef.
| 0 | none—Does not change the approximation coefficients. | | 1 | threshold—Applies the same thresholding operation to the approximation coefficients. | | 2 | detrend—Sets the approximation coefficients to 0. |
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signal specifies the input signal.
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levels specifies the number of levels in the discrete wavelet analysis. levels must be a positive integer no greater than log2(Ls), where Ls is the length of the 1D signal or the minimum dimensional size of the 2D signal. The default is –1, which indicates that the VI sets levels as the largest integer no greater than log2(Ls).
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wavelet specifies the wavelet type to use for the discrete wavelet analysis. The default is db02. The options include two types: orthogonal (Haar, Daubechies (dbxx), Coiflets (coifx), Symmlets (symx)) and biorthogonal (FBI, Biorthogonal (biorx_x)), where x indicates the order of the wavelet.
The higher the order, the smoother the wavelet. The orthogonal wavelets are not redundant and are suitable for signal or image denoising and compression. The biorthogonal wavelets usually have the linear phase property and are suitable for signal or image feature extraction. If you want to use other types of wavelets, do not wire this input. Instead, use the Wavelet Design Express VI to design the wavelet you want, bundle the resulting analysis and synthesis filters, and then wire them to the filter banks input.
|
|
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.
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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.
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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.
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|
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.
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|
filter banks specifies the analysis filter banks and the synthesis filter banks for the wavelet you specify. If you specify a value for filter banks, 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.
|
analysis filters specifies the coefficients of the lowpass analysis filters and the highpass analysis filters for the wavelet you specify.
|
lowpass specifies the coefficients of the lowpass analysis filter, which the VI uses to compute the approximation coefficients.
|
|
highpass specifies the coefficients of the highpass analysis filter, which the VI uses to compute the detail coefficients.
|
|
|
synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters for the wavelet you specify.
|
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.
|
|
|
|
user defined thresholds specifies thresholds you define to rescale the wavelet coefficients. The length of user defined thresholds must equal levels. The first element of user defined thresholds contains the threshold for the detail coefficients at the largest level, and the last element of user defined thresholds contains the threshold for the detail coefficients at the first level. If you specify a value for user defined thresholds, the VI keeps the approximation coefficients unchanged and ignores the settings in thresholding rule, rescaling method, and option for approx coef.
|
|
denoised signal contains the signal after denoising.
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|
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.
|
|
|
thresholds settings specifies the settings for the thresholding approximation coefficients and detail coefficients from the wavelet decomposition.
|
thresholding rule specifies the threshold selection rules. If you specify a value for user defined thresholds, the VI ignores the settings in thresholding rule.
| 0 | SURE (default)—Uses the principle of Stein's Unbiased Risk Estimate (SURE) to estimate the threshold. | | 1 | Hybrid—Finds a compromise between the SURE method and the Universal method. When the signal-to-noise ratio of the noisy signal is very low, the VI uses the Universal method to estimate the threshold. | | 2 | Universal—Sets the threshold to sqrt(2×log(Ls)), where Ls is the signal length. | | 3 | Minimax—Uses the minimax principle to estimate the threshold. |
|
|
rescaling method specifies the method to use to estimate the noise variance at each level. The default is single level. The VI uses the noise variance to rescale the threshold. Therefore, you can update the thresholds with the noise variance. If you specify a value for user defined thresholds, the VI ignores the settings in rescaling method.
| 0 | one—Specifies that the noise is white with unit variance. | | 1 | single level—Specifies that the noise is white. The VI estimates the noise standard deviation from the wavelet coefficients at the first level. | | 2 | multiple levels—Specifies that the noise does not have to be white. The VI estimates the noise standard deviation at each level independently. |
|
|
soft threshold? specifies to use the soft thresholding method. The default is TRUE, which indicates that the VI uses the soft thresholding method. If soft threshold? is FALSE, the VI uses the hard thresholding method.
|
|
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option for approx coef specifies the operation for the approximation coefficients from the wavelet decomposition. The default is none. If you specify a value for user defined thresholds, the VI ignores the settings in option for approx coef.
| 0 | none—Does not change the approximation coefficients. | | 1 | threshold—Applies the same thresholding operation to the approximation coefficients. | | 2 | detrend—Sets the approximation coefficients to 0. |
|
|
signal specifies the input signal.
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|
levels specifies the number of levels in the discrete wavelet analysis. levels must be a positive integer no greater than log2(Ls), where Ls is the length of the 1D signal or the minimum dimensional size of the 2D signal. The default is –1, which indicates that the VI sets levels as the largest integer no greater than log2(Ls).
|
|
wavelet specifies the wavelet type to use for the discrete wavelet analysis. The default is db02. The options include two types: orthogonal (Haar, Daubechies (dbxx), Coiflets (coifx), Symmlets (symx)) and biorthogonal (FBI, Biorthogonal (biorx_x)), where x indicates the order of the wavelet.
The higher the order, the smoother the wavelet. The orthogonal wavelets are not redundant and are suitable for signal or image denoising and compression. The biorthogonal wavelets usually have the linear phase property and are suitable for signal or image feature extraction. If you want to use other types of wavelets, do not wire this input. Instead, use the Wavelet Design Express VI to design the wavelet you want, bundle the resulting analysis and synthesis filters, and then wire them to the filter banks input.
|
|
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.
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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.
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|
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.
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|
|
filter banks specifies the analysis filter banks and the synthesis filter banks for the wavelet you specify. If you specify a value for filter banks, 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.
|
analysis filters specifies the coefficients of the lowpass analysis filters and the highpass analysis filters for the wavelet you specify.
|
lowpass specifies the coefficients of the lowpass analysis filter, which the VI uses to compute the approximation coefficients.
|
|
highpass specifies the coefficients of the highpass analysis filter, which the VI uses to compute the detail coefficients.
|
|
|
synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters for the wavelet you specify.
|
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.
|
|
|
|
user defined thresholds specifies thresholds you define to rescale the wavelet coefficients. The length of user defined thresholds must equal levels. The first element of user defined thresholds contains the threshold for the detail coefficients at the largest level, and the last element of user defined thresholds contains the threshold for the detail coefficients at the first level. If you specify a value for user defined thresholds, the VI keeps the approximation coefficients unchanged and ignores the settings in thresholding rule, rescaling method, and option for approx coef.
|
|
denoised signal contains the signal after denoising.
|
|
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.
|
|
|
thresholds settings specifies the settings for the thresholding approximation coefficients and detail coefficients from the wavelet decomposition.
|
thresholding rule specifies the threshold selection rules. If you specify a value for user defined thresholds, the VI ignores the settings in thresholding rule.
| 0 | SURE (default)—Uses the principle of Stein's Unbiased Risk Estimate (SURE) to estimate the threshold. | | 1 | Hybrid—Finds a compromise between the SURE method and the Universal method. When the signal-to-noise ratio of the noisy signal is very low, the VI uses the Universal method to estimate the threshold. | | 2 | Universal—Sets the threshold to sqrt(2×log(Ls)), where Ls is the signal length. | | 3 | Minimax—Uses the minimax principle to estimate the threshold. |
|
|
rescaling method specifies the method to use to estimate the noise variance at each level. The default is single level. The VI uses the noise variance to rescale the threshold. Therefore, you can update the thresholds with the noise variance. If you specify a value for user defined thresholds, the VI ignores the settings in rescaling method.
| 0 | one—Specifies that the noise is white with unit variance. | | 1 | single level—Specifies that the noise is white. The VI estimates the noise standard deviation from the wavelet coefficients at the first level. | | 2 | multiple levels—Specifies that the noise does not have to be white. The VI estimates the noise standard deviation at each level independently. |
|
|
soft threshold? specifies to use the soft thresholding method. The default is TRUE, which indicates that the VI uses the soft thresholding method. If soft threshold? is FALSE, the VI uses the hard thresholding method.
|
|
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option for approx coef specifies the operation for the approximation coefficients from the wavelet decomposition. The default is none. If you specify a value for user defined thresholds, the VI ignores the settings in option for approx coef.
| 0 | none—Does not change the approximation coefficients. | | 1 | threshold—Applies the same thresholding operation to the approximation coefficients. | | 2 | detrend—Sets the approximation coefficients to 0. |
|
 |
signal is the input signal.
|
|
levels specifies the number of levels in the discrete wavelet analysis. levels must be a positive integer no greater than log2(Ls), where Ls is the length of the 1D signal or the minimum dimensional size of the 2D signal. The default is –1, which indicates that the VI sets levels as the largest integer no greater than log2(Ls).
|
|
wavelet specifies the wavelet type to use for the discrete wavelet analysis. The default is db02. The options include two types: orthogonal (Haar, Daubechies (dbxx), Coiflets (coifx), Symmlets (symx)) and biorthogonal (FBI, Biorthogonal (biorx_x)), where x indicates the order of the wavelet.
The higher the order, the smoother the wavelet. The orthogonal wavelets are not redundant and are suitable for signal or image denoising and compression. The biorthogonal wavelets usually have the linear phase property and are suitable for signal or image feature extraction. If you want to use other types of wavelets, do not wire this input. Instead, use the Wavelet Design Express VI to design the wavelet you want, bundle the resulting analysis and synthesis filters, and then wire them to the filter banks input.
|
|
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.
|
|
|
filter banks specifies the analysis filter banks and the synthesis filter banks for the wavelet you specify. If you specify a value for filter banks, 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.
|
analysis filters specifies the coefficients of the lowpass analysis filters and the highpass analysis filters for the wavelet you specify.
|
lowpass specifies the coefficients of the lowpass analysis filter, which the VI uses to compute the approximation coefficients.
|
|
highpass specifies the coefficients of the highpass analysis filter, which the VI uses to compute the detail coefficients.
|
|
|
synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters for the wavelet you specify.
|
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.
|
|
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user defined thresholds specifies thresholds you define to rescale the wavelet coefficients. The length of user defined thresholds must equal levels. The first element of user defined thresholds contains the threshold for the detail coefficients at the largest level, and the last element of user defined thresholds contains the threshold for the detail coefficients at the first level. If you specify a value for user defined thresholds, the VI keeps the approximation coefficients unchanged and ignores the settings in thresholding rule, rescaling method, and option for approx coef.
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denoised signal contains the signal after denoising.
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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.
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status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
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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.
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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.
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thresholds settings specifies the settings for the thresholding approximation coefficients and detail coefficients from the wavelet decomposition.
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thresholding rule specifies the threshold selection rules. If you specify a value for user defined thresholds, the VI ignores the settings in thresholding rule.
| 0 | SURE (default)—Uses the principle of Stein's Unbiased Risk Estimate (SURE) to estimate the threshold. | | 1 | Hybrid—Finds a compromise between the SURE method and the Universal method. When the signal-to-noise ratio of the noisy signal is very low, the VI uses the Universal method to estimate the threshold. | | 2 | Universal—Sets the threshold to sqrt(2×log(Ls)), where Ls is the signal length. | | 3 | Minimax—Uses the minimax principle to estimate the threshold. |
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rescaling method specifies the method to use to estimate the noise variance at each level. The default is single level. The VI uses the noise variance to rescale the threshold. Therefore, you can update the thresholds with the noise variance. If you specify a value for user defined thresholds, the VI ignores the settings in rescaling method.
| 0 | one—Specifies that the noise is white with unit variance. | | 1 | single level—Specifies that the noise is white. The VI estimates the noise standard deviation from the wavelet coefficients at the first level. | | 2 | multiple levels—Specifies that the noise does not have to be white. The VI estimates the noise standard deviation at each level independently. |
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soft threshold? specifies to use the soft thresholding method. The default is TRUE, which indicates that the VI uses the soft thresholding method. If soft threshold? is FALSE, the VI uses the hard thresholding method.
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signal is the 2D input signal.
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levels specifies the number of levels in the discrete wavelet analysis. levels must be a positive integer no greater than log2(Ls), where Ls is the length of the 1D signal or the minimum dimensional size of the 2D signal. The default is –1, which indicates that the VI sets levels as the largest integer no greater than log2(Ls).
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wavelet specifies the wavelet type to use for the discrete wavelet analysis. The default is db02. The options include two types: orthogonal (Haar, Daubechies (dbxx), Coiflets (coifx), Symmlets (symx)) and biorthogonal (FBI, Biorthogonal (biorx_x)), where x indicates the order of the wavelet.
The higher the order, the smoother the wavelet. The orthogonal wavelets are not redundant and are suitable for signal or image denoising and compression. The biorthogonal wavelets usually have the linear phase property and are suitable for signal or image feature extraction. If you want to use other types of wavelets, do not wire this input. Instead, use the Wavelet Design Express VI to design the wavelet you want, bundle the resulting analysis and synthesis filters, and then wire them to the filter banks input.
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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.
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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.
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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.
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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.
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filter banks specifies the analysis filter banks and the synthesis filter banks for the wavelet you specify. If you specify a value for filter banks, 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.
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analysis filters specifies the coefficients of the lowpass analysis filters and the highpass analysis filters for the wavelet you specify.
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lowpass specifies the coefficients of the lowpass analysis filter, which the VI uses to compute the approximation coefficients.
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highpass specifies the coefficients of the highpass analysis filter, which the VI uses to compute the detail coefficients.
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synthesis filters specifies the coefficients of the lowpass synthesis filters and the highpass synthesis filters for the wavelet you specify.
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lowpass specifies the coefficients of the lowpass synthesis filter, which the VI uses to filter the interpolated approximation coefficients in the wavelet reconstruction.
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highpass specifies the coefficients of the highpass synthesis filter, which the VI uses to filter the interpolated detail coefficients in the wavelet reconstruction.
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user defined thresholds specifies thresholds you define to rescale the wavelet coefficients. The length of user defined thresholds must equal levels. The first element of user defined thresholds contains the threshold for the detail coefficients at the largest level, and the last element of user defined thresholds contains the threshold for the detail coefficients at the first level. If you specify a value for user defined thresholds, the VI keeps the approximation coefficients unchanged and ignores the settings in thresholding rule and rescaling method.
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denoised signal contains the signal after denoising.
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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.
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status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
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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.
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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.
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The VI completes the following steps to implement the noise reduction for signals and images using wavelet transforms.
To perform complex signal denoising, use the UWT method.
For the decomposition method, the DWT method is more efficient, but the UWT method provides better denoising performance because it can help reduce artifacts, such as Gibbs oscillation.
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