Lossy Compression with Near-uniform Encoder Outputs

Badri N Vellambi; Joerg Kliewer; Matthieu Bloch

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arXiv · 1602.06902

Lossy Compression with Near-uniform Encoder Outputs

Badri N Vellambi·Joerg Kliewer·Matthieu Bloch

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Abstract

It is well known that lossless compression of a discrete memoryless source with near-uniform encoder output is possible at a rate above its entropy if and only if the encoder is randomized. This work focuses on deriving conditions for near-uniform encoder output(s) in the Wyner-Ziv and the distributed lossy compression problems. We show that in the Wyner-Ziv problem, near-uniform encoder output and operation close to the WZ-rate limit is simultaneously possible, whereas in the distributed lossy compression problem, jointly near-uniform outputs is achievable in the interior of the distributed lossy compression rate region if the sources share non-trivial G\'{a}cs-K\"{o}rner common information.

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Badri N Vellambi, Joerg Kliewer, Matthieu Bloch. 2016-02-22. Lossy Compression with Near-uniform Encoder Outputs. https://arxiv.org/abs/1602.06902

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