Low-rate hybrid Wyner-Ziv coding of Laplace-Markov source using uniform scalar quantization

Hybrid Wyner-Ziv coders which employ a combination of Wyner-Ziv coding and differential pulse code modulation (DPCM) encoding have recently gained popularity for applications such as video coding. In this paper we analyze the low-rate operational rate distortion performance of Wyner-Ziv coding using uniform scalar quantization, in the context of such hybrid coders. Motivated by video we consider the compression of a first-order Laplace-Markov source, and derive approximate analytical rate and distortion expressions which are accurate at low rates. We utilize the derived analytical expressions to address the problem of determining the optimal quantization interval ratio of the Wyner-Ziv and DPCM scalar quantizers, for a range of rates.