Improv E M E N Ts on Seismic Data Compression and Migration Using Compressed Data with the Exible Segmentation Sc Hemefor Local Cosine Transform

Best basis searc hing algorithm based on binary in general M ary segmentation was constructed by Coifman and Wickerhauser and widely used for signal processing How ever there are several problems with the binary scheme First the binary segmentation is in exible in group ing signals along the axis Secondly the binary based segmentation method is very sensitiv e to time space shifts of the original signal such that the resulted best basis will change a great deal if the signal is shifted by some samples Thirdly the reconstruction distortion after compression is rela tively strong Wu and Wang have designed a new exible segmentation algorithm with ar bitrary time space segmentation which addresses the above mentioned problems caused by the bi nary segmentation scheme In that paper the adv an tages of the new exible segmen tation tech nique over the binary scheme are demonstrated by sho wing the removal of the constraint of dyadic segmentation reduction of time space shift sensi tivity and reconstruction distortions and superior performance in seismic data compression We ap ply our exible segmentation scheme to real D seismic data compression and study the e ects of data compression by the new method on imag ing F romthe comparison with the con ventional binary scheme we see that the decompressed data has less distortion and the migrated image using the decompressed data has better quality