Increasing Correlation using a Few Bits for Multiple Description Coding

In this paper we investigated methods that increase correlation between two values using one or two bits of extra information. For methods that use one bit, we investigated '1-bit quantization,' 'sign correction' and 'difference quantization' methods. For those that use two bits, we investigated '2-bit quantization,' 'sign correction+difference quantization' and '2-bit difference quantization' methods. From theoretical analysis and numerical experiments, it has been found that the quantization-based method is best when correlation of the original data is weak, while 'difference quantization' or combination of sign correction is better when the original data have strong correlation. Then we applied the methods to multiple description coding of speech signals.