Quantization with an adjustable codeword length penalty

Quantizers are generally designed either for fixed-rate coding or variable-rate coding. Under common conditions, variable-rate quantization leads to the same mean distortion for all quantization cells whereas fixed-rate is associated with a fixed bit allocation for each quantization operation. We show that both are special cases of the solution of a more general constraint that facilitates a practical trade-off between mean rate and rate outliers and mean distortion and outliers in distortion. The proposed constraint weights the codeword lengths exponentially. The resulting quantizers are suitable for commonly occurring scenarios such as those where a limited variability in rate can be tolerated by the network, those where the signal model may not be accurate, and those where source redundancy is used to counter channel errors.

• Type: Journal
• Year: 2011
• Where: ICASSP
• Authors: W. Bastiaan Kleijn, Moo Young Kim
• Keywords: ICASSP 2011, Mean Distortion, Quantization Cells, Signal Processing, fixed Bit Allocation