A Note on Quantization of Image Sub-Bands

Abstract

Sub-band image coding is Considered to be a promising technique for high fidelity compression of high resolution images, in the traditional sub-band image coding algorithm where a scalor quantizer is used, however high frequency sub-band signals are usually discarded. Which Incurs rather noticeable degradation of reconstruction quality. To solve the above problem, the work herein introduces improved Permutation codes, recently developed by the authors extending the concept of prototypal permutation codes, into sub-band image coding, and applies improved permutation codes to quantization of high frequency sub-band signals. The simulation results demonstrate that improved permutation codes are more useful than an entropy-constrained scalor quantizer as a means for quantizing high frequency sub-band signals, Moreover, the work herein develops an adaptive quantization technique combining improved permutation codes and entropy-constrained scalor quantizers, and demonstrates the usefulness by computer simulations.