readgssi.filtering

readgssi.filtering.bgr(ar, header, win=0, verbose=False)

Horizontal background removal (BGR). Subtracts off row averages for full-width or window-length slices. For usage see Getting rid of horizontal noise.

Parameters

  • ar (numpy.ndarray) – The radar array

  • header (dict) – The file header dictionary

  • win (int) – The window length to process. 0 resolves to full-width, whereas positive integers dictate the window size in post-stack traces.

Return type

numpy.ndarray

readgssi.filtering.bp(ar, header, freqmin, freqmax, zerophase=True, verbose=False)

Vertical butterworth bandpass. This filter is not as effective as triangular() and thus is not available through the command line interface or through readgssi.readgssi.readgssi().

Filter design and implementation are dictated by obspy.signal.filter.bandpass().

Parameters

  • ar (np.ndarray) – The radar array

  • header (dict) – The file header dictionary

  • freqmin (int) – The lower corner of the bandpass

  • freqmax (int) – The upper corner of the bandpass

  • zerophase (bool) – Whether to run the filter forwards and backwards in order to counteract the phase shift

  • verbose (bool) – Verbose, defaults to False

Return type

numpy.ndarray

readgssi.filtering.dewow(ar, verbose=False)

Polynomial dewow filter. Written by fxsimon.

Warning

This filter is still experimental.

Parameters

  • ar (numpy.ndarray) – The radar array

  • verbose (bool) – Verbose, default is False

Return type

numpy.ndarray

readgssi.filtering.triangular(ar, header, freqmin, freqmax, zerophase=True, verbose=False)

Vertical triangular FIR bandpass. This filter is designed to closely emulate that of RADAN.

Filter design is implemented by scipy.signal.firwin() with numtaps=25 and implemented with scipy.signal.lfilter().

Note

This function is not compatible with scipy versions prior to 1.3.0.

Parameters

  • ar (np.ndarray) – The radar array

  • header (dict) – The file header dictionary

  • freqmin (int) – The lower corner of the bandpass

  • freqmax (int) – The upper corner of the bandpass

  • zerophase (bool) – Whether to run the filter forwards and backwards in order to counteract the phase shift

  • verbose (bool) – Verbose, defaults to False

Return type

numpy.ndarray