Image Compression Technology Study Based On Region Of Interest

This thesis introduces the theory of image compression coding and the basic concepts of region of interest (ROI) coding, and explains the wavelet transform theory. Some kernel techniques in coding are especially introcuced, such as lifting scheme, building mask,.Maxshift and set partition in hierarchical tree. A new region segmentation method based on the analysis of the point and boundary feature is proposed. On the basis of this ,we further bring forward a blue print of ROI coding system based on TMS320C6201 EVM board, which shows high performance in test.In image compression processing, compression ratio and rebuilding image quality conficts each other. ROI coding is a solution of the problem by processing image regions with different compression ratios, with which we can acquire both high compression ratio and splendid image rebuilding quality. Wavelet tansform is a perfect mathematical tool of signal processing theory, and it has some very good features, such as multi-resolution analysis, and so on. It is the base theory of ROI coding. Lifting scheme is a fast realization of the pyramidal algorithm, and this scheme can decrease the time and space complexity of wavelet transform greatly.EZW and SPIHT are a milestone of wavelet image coding, being the most excellent wavelet coding algorithm. Both point and boundary are the most features of a image . It is proved to be a available method in matching target region that point and boundary are combined and compared each other.TMS320C6201 DSP chip possess powerful computing ability, parallelism and flexibility. Therefore we choose C6201 EVM board to realize ROI coding system.This dissertation introduces the principles of wavelet, and realize image ROI coding system on EVM board.