Uses multiresolution wavelet analysis to detect peaks or valleys in a signal. Wire data to the signal input to determine the polymorphic instance to use or manually select the instance.


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WA Multiscale Peak Detection Details

This VI executes the following steps to detect peaks by using a wavelet-based method.

  1. Calculates the undecimated wavelet transform (UWT) level based on the width and the UWT level based on the threshold frequency, separately. This VI chooses the greater UWT level from the two results to control the decomposition level.
  2. Performs UWT on the input signal by using the biorthogonal wavelet bior3_1 and the greater UWT level calculated in step 1.
  3. Searches for zero-crossing points in the detail coefficients at all levels.
  4. Selects the zero-crossing points at the largest scale as the coarse estimation of the real peaks.
  5. Searches the finer scale for the corresponding nearest zero-crossing point for each detected point.
  6. Repeats step 5 until this VI reaches the finest scale, which is the first level.

Examples

Refer to the following VIs for examples of using the WA Multiscale Peak Detection VI:

  • Breakdown Point Detection VI: labview\examples\Wavelet Analysis\WAApplications
  • ECG QRS Complex Detection VI: labview\examples\Wavelet Analysis\WAApplications
  • Peak Detection (Wavelet vs. Normal) VI: labview\examples\Wavelet Analysis\WAGettingStarted
  • Peak Detection in a Signal with Baseline Wandering VI: labview\examples\Wavelet Analysis\WAGettingStarted