High-rate quantization and transform coding with side information at the decoder
Signal Processing - Special section: Distributed source coding
Optimization of system performance for DVC applications with energy constraints over ad hoc networks
MMM'07 Proceedings of the 13th International conference on Multimedia Modeling - Volume Part II
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We extend the rate-distortion function for Wyner-Ziv coding of noisy sources with quadratic distortion, in the jointly Gaussian case, to more general statistics. It suffices that the noisy observation Z be the sum of a function of the side information Y and independent Gaussian noise, while the source data X must be the sum of a function of Y, a linear function of Z, and a random variable N such that the conditional expectation of N given Y and Z is zero, almost surely. Furthermore, the side information Y may be arbitrarily distributed in any alphabet, discrete or continuous. Under these general conditions, we prove that no rate loss is incurred due to the unavailability of the side information at the encoder. In the noiseless Wyner-Ziv case, i.e., when the source data is directly observed, the assumptions are still less restrictive than those recently established in the literature. We confirm, theoretically and experimentally, the consistency of this analysis with some of the main results on high-rate Wyner-Ziv quantization of noisy sources.