Processing Options

Detrending

Remove unwanted trends from the raw signal:

• linear: Remove a best-fit line
• demean: Subtract the mean
• polynomial: Fit and subtract a polynomial (e.g., degree 3)
• spline: Subtract a smooth spline fit

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Tapering

Apply a window to reduce spectral leakage near signal edges.

• Parameter: max_percentage (e.g., 0.05 for 5%)
• Supported Windows: cosine, hann, hamming, blackman, kaiser, flattop, slepian, and many more...

Analysis:
  process_1:
    name: 'rmean'
    method: 'linear'
  process_2:
    name: 'taper'
    method: 'cosine'
    max_percentage: 0.05

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Normalize

Rescale amplitude:

• 0: Normalize by maximum
• Custom value: Divide signal by provided constant

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Filtering

Apply filters to isolate specific frequency content.

• Parameters: freqmin, freqmax, zerophase, corners (poles)
• Filter Types:
• bandpass, lowpass, highpass, bandstop
• Parametric options: cheby1, cheby2, elliptic, bessel

ℹ️ Ensure freqmin < freqmax for band filters.

Analysis:
  process_1:
    name: 'rmean'
    method: 'linear'
  process_2:
    name: 'taper'
    method: 'cosine'
    max_percentage: 0.05
  process_3:
    name: 'normalize'
    norm: True
  process_4:
    name: 'filter'
    type: 'bandpass'
    fmin: 0.5
    fmax: 8.5
    corners: 4
    zerophase: True

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Denoising

Wiener Filter

• Parameters: time_window (seconds), noise_power
• Tip: If noise_power=0, it’s estimated from local variance.

Analysis:
  process_1:
    name: 'rmean'
    method: 'linear'
  process_2:
    name: 'taper'
    method: 'cosine'
    max_percentage: 0.05
  process_3:
    name: 'filter'
    type: 'bandpass'
    fmin: 0.5
    fmax: 8.5
    corners: 4
    zerophase: True
  process_4:
    name: "wiener_filter"
    time_window: 1.0
    noise_power: 0

Wavelet Denoise

• Parameters: wavelet_family (e.g., sym8), threshold (e.g., 0.05)

Analysis:
  process_1:
    name: 'rmean'
    method: 'linear'
  process_2:
    name: 'taper'
    method: 'cosine'
    max_percentage: 0.05
  process_3:
    name: 'filter'
    type: 'bandpass'
    fmin: 0.5
    fmax: 8.5
    corners: 4
    zerophase: True
  process_4:
    name: 'wavelet_denoise'
    dwt: 'sym8'
    threshold: 0.1

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Resampling

Adjust the sampling rate (e.g., for standardization):

• Parameters: new_sampling_rate, pre_filter (recommended: True)

Analysis:
  process_1:
    name: 'resample'
    sampling_rate: 20
    pre_filter: True

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Quick Resampling

This strategy makes a very fast resampling specially designg to speed up the plot of seismograms. Warning this resampling not prevents from aliasing effects.

• Parameters: factor, integers (recommended: True)

Analysis:
  process_1:
    name: 'raw'
    factor: 20
    integers: True

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Fill Gaps

• Methods: interpolate, latest (repeat last value)

Analysis:
  process_1:
    name: 'fill_gaps'
    method: 'latest'

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Differentiate

Estimate the signal’s derivative:

• Methods: gradient

Analysis:
  process_9:
    name: 'differentiate'
    method: 'spectral'

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Integrate

Reconstruct displacement or velocity:

• Methods: cumtrapz, spline

Analysis:
  process_1:
    name: 'integrate'
    method: 'spectral'

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Time Shifting

Shift traces forward or backward in time.

• Parameter: List of time shifts in seconds

Analysis:
  process_1:
    name: 'shift'
    time_shifts: [-5, 2] # list of shift seconds of the starttime. 
    phase: P #  if pick is vailable. 
    phase_theo: P #  if your trace header has event information.

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Remove Instrument Response

Convert raw counts to physical units (e.g., velocity or displacement):

• Parameters: pre_filt (list), water_level, units, inventory

  process_1:
    name: 'remove_response'
    water_level: 90
    units: 'VEL' # [ACC Wood Anderson]
    pre_filt: [0.005,0.008,45,48] # Hz, incremental frequencies defining the pre-filt

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Add Noise

White Noise:

• Parameter: SNR_dB relative to original trace

Colored Noise (optional, not in base config):

• Use exponent for control: 0 (white), 1 (pink), 2 (brown), -1 (blue), etc.

Analysis:
  process_1:
    name: 'add_noise'
    noise_type: 'white'
    SNR_dB: 1

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Spectral Whitening

Flattens signal spectrum while preserving phase:

• Parameters: freq_width (Hz), taper_edge (True/False)

Analysis:
  process_11:
    name: 'whitening'
    freq_width: 0.02
    taper_edge: True

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Time Normalization

Standardize temporal energy distribution:

• Methods: time-normalization, 1bit, clipping
• Parameters: norm_win, iterations

Analysis:
  process_1:
    name: 'time_normalization'
    method: 'time normalization'
    norm_win: 10

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Smoothing

Reduce high-frequency noise or jitter:

• Parameters: time_window, fwhm
• Methods: mean, gaussian, tkeo

Analysis:
  process_1:
    name: 'smoothing'
    method: 'gaussian'
    time_window: 5
    FWHM: 0.05

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Spike Removal

Removes isolated outliers using hampel algorithm:

• Parameters: window_size, threshold (in standard deviations)

  process_11:
    name: 'remove_spikes'
    window_size: 10
    n: 4

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