WA Denoise VI
- Updated2024-07-30
- 2 minute(s) read
Performs noise reduction for 1D or 2D signals by using the discrete wavelet transform (DWT) or undecimated wavelet transform (UWT). You must manually select the polymorphic instance to use.
WA Denoise Details
This VI completes the following steps to implement the noise reduction for signals and images using wavelet transforms.
- Applies the wavelet transform to the noisy data and obtains the detail coefficients and the approximation coefficients.
- Applies soft or hard thresholding to the resulting coefficients, thereby suppressing those coefficients smaller than a certain threshold. The thresholding rule and the rescaling method determine the threshold.
- Reconstructs the coefficients after thresholding and transforms them back into the original domain.
To perform denoising on complex signals, use the UWT method.
In general, the DWT is more efficient for decomposing signals, but the UWT provides better denoising performance because it can help reduce artifacts, such as Gibbs oscillation.
Examples
Refer to the following VIs for examples of using the WA Denoise VI:
- Denoise - 1D Complex Signal VI: labview\examples\Wavelet Analysis\WAGettingStarted
- Denoise - 1D Real Signal VI: labview\examples\Wavelet Analysis\WAGettingStarted
- Denoise - Image VI: labview\examples\Wavelet Analysis\WAGettingStarted