OVERVIEW
Here is a view of the GUI after a seismogram has been read and the CWT computed:

Functionality

- The purpose of the GUI is to allow experimentation with various block thresholding schemes on single trace seismic data to gain intuition on designing appropriate noise reduction workflows.
- A seismic data trace in SAC (Seismic Analysis Code) format is read into the GUI, a continuous wavelet transform (CWT) computed, and then processed using a variety of block thresholding tools.
- Operations are performed by choosing various menu functions and using the color buttons on the GUI.
- Once a flow has been determined, the MatLab function "BCseis_process" can be used to process a suite of seismograms.

Menu Functions

- File: Read and write SAC files, polygon files, and CWT files
- Plot: Plot the current CWT and Seismogram on a separate plot. Plot CWT of a chosen template on a separate plot.
- Parameters: Choose the wavelet type and resolution. Parameters will be displayed in the box to the upper right on the GUI.
- Calc: Refresh to original data and CWT, Undo last action, Compute CWT, Estimate Noise, Hard Threshold Noise, Soft Threshold Noise, Hard Threshold Signal, Soft Threshold Signal, Correlate template, SNR Detector.
- Help: Access the help webpages

Interactive Band Pass or Block

- Choose a band in scale and remove or reduce its amplitude. Amplitude outside of the band will be preserved.
- Choose a band in scale and keep or reduce its amplitude. Amplitude outside of the band will be zeroed out.
- The simple calculator at the bottom can be used with the MatLab data tip to determine a bandpass directly from the CWT scalogram.

Interactive Block Choice with Mouse

- Pick a region on the CWT plane to either keep and exclude all other CWT coefficients ("Include Block") or remove ("Exclude Block")

Choose Noise Time Bounds

- Enter the begin and end times of the region of the seismogram that will be used to estimate the noise.

Parameters for Noise Reduction Functions

- "Sigma Factor" is used in hard and soft thresholding of the signal using the chosen noise region.
- If "Donoho's Threshold Criterion" radiobutton is pushed, then sigma factor is calculated from the noise estimate.
- If ECDF radiobutton is pushed, then the ECDF method is used for denoising. (recommended)
- "N lower bound" is used in the SNR Detector function

Simple Calculator

- Enter numbers in either box and the calculator will convert to log10 from linear or linear to log10 after hitting the return button on the keyboard.

Choose the Display Time Window

- begin and end time for the seismogram and CWT plots. Press the "TLIM" button to replot.

Change the color saturation of the CWT plot

- Use the slider to increase the color saturation of the CWT plot. This usually allows better viewing of the CWT plot in interpreting what is signal and noise.

Standard MatLab tools for examining each plot

- Magnify and demagnify tools allow details of either plot to be informally examined. You may have to press the "TLIM" button to refresh to the correct time window display.
  The datatip can be used to estimate times, amplitudes, and scales.

The Canonical Seismogram

- Images on these help pages were taken from screen shots of processing an explosion recorded by the IRIS Wavefields Community Experiment that was deployed in June-November 2016 (Network YW in IRIS parlance). The data waveform can be found in /data as 5014.YW.0.sp0011.DPZ.

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