Patent ID: 6611625
Filing Date: 2003-08-26
Classification: G06T,H04N

Abstract:
A generalized scan interleaving-based encoding method using context values of neighboring pixels, for encoding pixels which were not sampled during down-sampling, after down-sampling pixels of a current layer in the sampling ratio of m/n in the vertical direction and mâ€²/nâ€² in the horizontal direction when input shape information are pixels of the current layer, wherein m, n and mâ€², nâ€² are arbitrary integers (zero is forbidden), and m<=n and mâ€²<=nâ€², the scan interleaving-based method comprising the steps of:(a) forming a bit stream of a base layer by encoding, through a predetermined encoding method, the base layer pixels which were down-sampled from the current layer pixels through 2K down-sampling and residual down-sampling in the vertical direction and the horizontal direction, respectively, wherein the exponent K satisfies K=0, 1, 2, . . . ; (b) dividing the current layer pixels into units of a predetermined block; (c) forming bit streams for all blocks of the current layer, by sequentially carrying out forming steps for pixels forming each block of the current layer, the forming steps comprising the steps of: (c1) encoding pixels, which were not sampled when vertical-direction 2L down-sampling was L-times recursively carried out in the step (a), using context values of neighboring pixels, wherein L is the largest integer less than or equal to log2(n/m); (c2) encoding pixels, which were not sampled during residual down-sampling in the ratio of [(m22)/n] in the vertical direction, using context values of neighboring pixels; (c3) encoding pixels, which were not sampled when horizontal-direction 2K down-sampling was K-times recursively carried out in the step (a), using context values of neighboring pixels, wherein K is the largest integer less than or equal to log2(nâ€²/mâ€²); (c4) encoding pixels, which were not sampled during residual down-sampling in the ratio of [(mâ€²2K)/nâ€²] in the horizontal direction in the step (a), using context values of neighboring pixels; and (c5) forming blocks of encoded bit streams by the block by arraying the bit streams encoded in the steps (c1), (c2), (c3), and (c4) in the order of steps (c4), (c3), (c2) and (c1); and (D) forming scalable bit streams by arraying bit streams of the current layer after the bit streams of the base layer.