A high-rate analysis of multiple description quantizers is presented for rth-power distortions and general source densities. Both, fixed-length and variable-length encoding of the quantizer indices are considered. Optimal companding functions are shown to be the same as for single-channel quantizers. As compared to the bound of Ozarow (1980), a gap of 8.69 dB and 3.07 dB exists between the entropy-constrained and level-constrained cases, respectively, for a memoryless Gaussian source and r=2.

The multiple description transform coder is introduced for sources with memory and an asymptotic analysis is presented for the squared error distortion. For stationary Gaussian sources, the optimal transform and the optimal bit allocation for the multiple description coder are identical to those for the single description coder.