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Synthetic shot gather

The synthetic shot gather consists of three hyperbolas. The dataset has been contaminated by random noise. For this 2-D dataset, n1=512 and n2=128. Figure 3, 4, 5, and 6 are the t-x domain and f-k domain results.

 
compcsg
compcsg
Figure 3
Synthetic shot gather in the t-x domain (scale = 0.715). In this case, the compression ratio is 50 and SNR is 7.69dB. The two figures are plotted on the same scale.
a: Original dataset.
b: Compressed/decompressed dataset.
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compcsgdiff
compcsgdiff
Figure 4
Difference of the two results in last figure. There is little remnant of the three hyperbolas in the figure.
a: Difference shown on the absolute scale.
b: Difference shown on the relative scale.
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ftcompcsg
ftcompcsg
Figure 5
Synthetic shot gather in the f-k domain.
a: Original dataset.
b: Compressed/decompressed dataset.
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ftcompcsgdiff
ftcompcsgdiff
Figure 6
Difference of the two results in last figure. High frequency noise is the main component of this figure.
a: Difference shown on the absolute scale.
b: Difference shown on the relative scale.
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After one compress/decompress cycle, random noise is removed from the input dataset. It means that this technique attains high compression ratios by filtering uncoherent component. We conduct a series of tests using different scale values. As shown in Figure 7 and Figure 8, with the increase of scale value, the compression ratio increases more and more sharply and SNR decreases more and more slowly.

 
csgcr
csgcr
Figure 7
Compression ratio increases from 6 to 76, when scale value increases from 0.05 to 0.9.
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csgsnr
csgsnr
Figure 8
SNR decreases from 32.88dB to 7.11dB, when scale value increases from 0.05 to 0.9.
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previous up next print clean
Next: Synthetic 3-D data Up: APPLICATION OF WAVELET-BASED COMPRESSION Previous: APPLICATION OF WAVELET-BASED COMPRESSION
Stanford Exploration Project
11/12/1997