Lossy Source Compression of Non-Uniform Binary Sources Using GQ-LDGM Codes

Lorenzo Cappellari

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arXiv · 1004.2628

Lossy Source Compression of Non-Uniform Binary Sources Using GQ-LDGM Codes

Lorenzo Cappellari

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Abstract

In this paper, we study the use of GF(q)-quantized LDGM codes for binary source coding. By employing quantization, it is possible to obtain binary codewords with a non-uniform distribution. The obtained statistics is hence suitable for optimal, direct quantization of non-uniform Bernoulli sources. We employ a message-passing algorithm combined with a decimation procedure in order to perform compression. The experimental results based on GF(q)-LDGM codes with regular degree distributions yield performances quite close to the theoretical rate-distortion bounds.

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Lorenzo Cappellari. 2010-07-08. Lossy Source Compression of Non-Uniform Binary Sources Using GQ-LDGM Codes. https://arxiv.org/abs/1004.2628

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