Fast and efficient progressive image coding and transmission using wavelet decomposition

Date

1999-05

Journal Title

Journal ISSN

Volume Title

Publisher

Texas Tech University

Abstract

With the recent boom in multimedia and the Iniernel. miage compression and techniques for progressive image transmission have become quite important. This thesis describes the concept and design of a codec for progressixc image transmission highlighted by a new technique SPHIT (Set Partitioning in Hierarchical Trees). This technique works on the principles of partial ordering by magnitude utilizing a sci partitioning sorting algorithms, ordered bit plane transmission, and exploitation of selfsimilarity across different scales of an image wavelet transform. The said principles of SPIHT are no different than what was described in the original EZW by J. P. Shapiro. But the approach for implementation of SPIHT is significantly different. Here the ordering information for image data is not explicitly transmitted. Instead, the fact that the execution path of any algorithm is defined by the results of the comparisons on its branching points is exploited to obtain ordering information at the decoder. The decoder and the encoder not only share the same sorting algorithm, but also the same execution path. Thus, the decoder can recover the ordering information from its execution path, which happens to be identical to that of the encoder. An attempt to highlight the basic differences between the EZW and SPIHT is made by taking an example of 8 x 8 image section.

Description

Citation