Detects ridges by extracting peaks of each row of a signal.


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Inputs/Outputs

  • cbool.png local threshold? (F) —

    local threshold? specifies the method to use to choose the threshold. If local threshold? is TRUE, this VI sets the threshold for each row of the signal. If local threshold? is FALSE, this VI uses the global threshold. The default is FALSE.

  • c2ddbl.png signal —

    signal specifies the 2D input signal.

  • cdbl.png threshold ratio —

    threshold ratio specifies the threshold to reject small peaks. The threshold equals (Max-Min)xthreshold ratio+Min, where Max and Min are the maximum and minimum value of the signal, respectively. threshold ratio must be between 0 and 1.

  • ci32.png width —

    width specifies the width, in samples, of the peaks of each row of signal. 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.

  • i2du8.png ridge —

    ridge returns the ridges this VI detects. ridge has the same dimensions as signal. The values in ridge are 0 or 1, where 1 indicates that a peak exists at the location along the row direction. Use an intensity graph to display the ridges.

  • ierrcodeclst.png error out —

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

    • WA Multiscale Ridge Detection Details

    You usually can characterize the ridges of the 2D input signal by the peaks in each row. Therefore, this VI carries out the robust peak detection using the wavelet-based method on each row. All detected peaks form the ridges. For signals with ridges parallel to the row direction, you can detect the ridges from the transposed 2D signals.

    Examples

    Refer to the Spectrogram Ridge Detection VI in the labview\examples\Wavelet Analysis\WAGettingStarted directory for an example of using the WA Multiscale Ridge Detection VI.