Block adaptive subband VPIC

SBC is combined with VPIC to eliminate the blockiness and reduce the jagged edge artifact. A totally new set of 2/spl times/2 patterns is designed to code the highly compacted subband signals. The results on two bit allocation schemes are evaluated. Compare to the full band VPIC, the performance of the new technique is so good that we only need to retain the lowest frequency band while the other high frequency ones can be discarded.<
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