Multiple description image coding based on delta-sigma quantization with rate-distortion optimization.

Recently, Østergaard and Zamir revealed the connection between multiple description coding and delta-sigma quantization (DSQ). The principle has been applied to image coding, with main focus on the framework where each block is processed separately. In this brief, we propose a two-channel multiple description image coding scheme that performs inter-block processing. The source image is first rearranged into a block sequence. Then, vector DSQ is performed with a bank of noise-shaping filters. Their coefficients as well as the quantization steps are chosen by a rate-distortion optimization algorithm. A post-processing algorithm is proposed for side decoding. Experiment results show the improvement achieved by the proposed scheme in terms of both peak signal-to-noise ratio values and subjective quality.