BAND PASS/BLOCK
Band pass/blocking is basically the construction of a band pass or reject filter where wavelet coefficients are modified over a scale bandpass. For example, in the above figure showing the Bandpass Blocking box of the GUI, a scale band is chosen between 1 and 1000 seconds. In addition, a threshold of 0% is chosen. The CWT coefficients in this band will be multiplied by 0. If 5% had been chosen, then the coefficients would be multiplied by 0.05. After multiplication, the inverse CWT is computed to display the filtered seismogram.
Here is the result using the canonical seismogram:
Here is an example for band pass filtering with the CWT. A scale range of 0.3 to 1s is chosen for the band pass.
giving the result

Note that the scale unit is seconds. The CWT Scalogram is plotted in log10(scale) vs time. In experimenting with Bandpass Blocking it is helpful to use the MatLab datatip
to choose scale points on the Scalogram. The numerical values will be in log10. The Scale Numeric Calculator at the bottom of the GUI
is provided to covert these log10 data values to actual values that can be input in the Bandpass Blocking edit boxes.
To use the calculator, input a value in a box and press the keyboard <return> key. The conversion goes both ways.

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