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In conventional block-based moving-picture coding, a motion-compensated prediction is generated for each "interframe". Then the prediction is subtracted from the input frame, leaving a residue. Standards like H.26x and MPEG I and II use the Discrete Cosine Transform (DCT) for coding the residue. We have developed an alternative method for residue coding using "pattern zerotrees". Structured spatial patterns are used to map residue pixel values into a quadtree structure, which is then coded in significance order with the SPIHT algorithm. The wavelet coefficient values of standard zerotree coding are replaced by untransformed (but carefully positioned) residue pixel values. The new zerotree pattern coding method compresses as well as zerotree wavelet coding and much better than DCT coding over error-free channels. Over noisy channels, zerotree pattern coding provides build-in error resilience, allowing transmission of residue data without error control overhead. A simple post-processing technique provides additional error concealment.

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