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


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Inputs/Outputs

  • cbool.png initialize? (F) —

    initialize? specifies whether to initialize the internal state of the block of data to zero. The default is FALSE.

  • cu16.png peaks/valleys —

    peaks/valleys specifies whether this VI looks for peaks or valleys in the signal. The default is peaks.

  • cmsdt.png signal —

    signal specifies the input signal.

  • cdbl.png threshold —

    threshold specifies the threshold this VI uses to reject peaks or valleys of a particular size. If this VI looks for peaks, this VI ignores peaks with a peak amplitude less than threshold. If this VI looks for valleys, this VI ignores valleys with a valley amplitude greater than threshold.

  • ci32.png width —

    width specifies the width, in number of samples, of the peaks or valleys. This VI coerces the value to a power of 2.

  • cerrcodeclst.png error in (no error) —

    error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

  • ccclst.png detrend settings —

    detrend settings specifies the settings this VI uses to remove the trend from the signal.

  • cbool.png detrend? (F) —

    detrend? specifies whether this VI removes the trend from the signal. The default is FALSE, which means this VI does not remove the trend.

  • cdbl.png threshold frequency —

    threshold frequency specifies the upper frequency limit, in hertz, of the trend that this VI removes from the signal. The threshold frequency determines the wavelet transform level. The wavelet transform level specifies the number of levels in the discrete wavelet analysis, where more levels result in a longer delay when you run this VI. The wavelet transform level is floor(log2[sampling rate/(2*threshold frequency)]). The floor function rounds a value to the nearest integer towards negative infinity. The default is -1, which means this VI sets the threshold frequency as sampling rate/4.

  • i1ddbl.png location —

    location returns the locations of the peaks or valleys this VI detects.

  • i1ddbl.png amplitude —

    amplitude returns the amplitudes of the peaks or valleys this VI detects.

  • i1dcclst.png peak plot —

    peak plot returns the signal and the peaks or valleys this VI detects. If detrend? is TRUE, peak plot also returns the trend of the input signal. You can plot this information on an XY graph.

  • ierrcodeclst.png error out —

    error out contains error information. This output provides standard error out functionality.

    • WA Online Multiscale Peak Detection Details

    This VI executes steps similar to the WA Multiscale Peak Detection VI to detect peaks by using a wavelet-based method. Refer to the Details section of the WA Multiscale Peak Detection VI for more information about how this VI detects peaks.

    Examples

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

    • ECG Heart Rate Monitor (Online) VI: labview\examples\Wavelet Analysis\WAApplications
    • Online Peak Detection and Display in Strip Mode VI: labview\examples\Wavelet Analysis\WAGettingStarted
    • ECG QRS Complex Detection VI: labview\examples\Wavelet Analysis\WAApplications