MULTI-LEVEL WAVELET BASED IMAGE CODING OVER LIFTING SCHEME FOR EMBEDDED WIRELESS DEVICES

摘要

This paper provides a concise synopsis in the application of Lifting Scheme (LS) in wavelet image coding. Lifting theorem was applied via LS 5/3 wavelet transform to develop a design wherein multipliers are replaced with shifters, thus lowering the volume of operations entailed in the process of computing a DWT to approximately one-half of the requisite volumes of a convolution approach. Consequently, the computations required for image coding are reduced and less intricate. In addition, the lifting scheme can be modified to meet the demands of in-place computation, for DWT to be implemented in low memory systems, which presents a unique solution to the issues associated with existing time consuming software algorithms. This LS filter consists of integer adder units and binary shifter instead of multiplier and divider units found in convolution based filters; thus it has been modified to provide energy efficient hardware performance. The low power 5/3 LS based wavelet transform involves solutions developed to resolve the energy and bandwidth communication problems related to image data transmission. These solutions entail constructing 2D-DWT image codec architecture to save the computational and communication energy erstwhile dissipated in existing architectures.