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| A 1-D time-varying median filter for seismic random, spike-like noise elimination | |
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A simple definition of the SNR was introduced by Liu and Li (1997). Window , a part
of the seismic record, can be chosen for SNR analysis:
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(2) |
Further assumptions are: waveform, amplitude, and phase of seismic
wavelet in window keep stable in respect to distance ``''; noise is
``zero mean'' randomly distributed, along with survey-line direction being independent
(decorrelated) of the signal, so that
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(3) |
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(4) |
where is amplitude of signal, and is amplitude of noise. These
assumptions generally imply a limitation to this method, but they
can be satisfied if the local window is chosen in the stable signal region of the
seismic section. So if the signal energy in the window is
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(5) |
the noise energy can be calculated by
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(6) |
Finally, a decibel expression of the SNR is estimated as
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(7) |
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| A 1-D time-varying median filter for seismic random, spike-like noise elimination | |
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Next: 1-D time-varying median filter
Up: Theoretical basis
Previous: 1-D stationary median filter
2013-07-26