Low density codes achieve the rate-distortion bound

Emin Martinian; Martin J. Wainwright

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arXiv · cs/0601123

Low density codes achieve the rate-distortion bound

Emin Martinian·Martin J. Wainwright

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Abstract

We propose a new construction for low-density source codes with multiple parameters that can be tuned to optimize the performance of the code. In addition, we introduce a set of analysis techniques for deriving upper bounds for the expected distortion of our construction, as well as more general low-density constructions. We show that (with an optimal encoding algorithm) our codes achieve the rate-distortion bound for a binary symmetric source and Hamming distortion. Our methods also provide rigorous upper bounds on the minimum distortion achievable by previously proposed low-density constructions.

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Emin Martinian, Martin J. Wainwright. 2006-01-30. Low density codes achieve the rate-distortion bound. https://arxiv.org/abs/cs/0601123

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