Enhancing Two-Stage Multiple Description Scalar Quantization

In this letter we consider enhancing coding performance of two-stage multiple description scalar quantization. An enhancement scheme is proposed to make the product of central and side distortions closer to the rate-distortion bound of multiple description coding under the high-resolution assumption. We show analytically that the second stage refinement information, i.e., the quantized residual errors, can be used to further reduce the side distortions apart from the central distortion, which is substantiated with a memoryless Gaussian source.