Codecell Contiguity in Optimal Fixed-Rate and Entropy-Constrained Network Scalar Quantizers
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چکیده
We consider the properties of optimal xed-rate and entropy-constrained scalar quantizers for nite alphabet sources. In particular, w econsider conditions under which the optimal scalar quantizer with contiguous codecells achieves performance no worse than the optimal scalar quantizer without the constraint of codecell contiguit y.In addition to traditional scalar quantizers, w econsider multi-resolution scalar quantizers and multiple description scalar quantizers and also look brie y at codes with decoder side information (WynerZiv codes). While the conditions under which codecell contiguit y is consistent with optimality in xed-rate and entropy-constrained scalar quantization are quite broad, even with the squared error distortion measure, codecell contiguity in xed-rate and entropy-constrained multi-resolution, multiple description, and Wyner-Ziv scalar quantization can preclude optimality for some sources.
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تاریخ انتشار 2002