Research On Medical Image Compression Method Based On Wavelet Analysis

With the development and combination of long-distance communication technology and modern medical information technology,a new type of medical service method which called telemedicine emerges.With the comprehensive popularization of informatization,telemedicine technology is widely used because of its convenient and efficient features that can realize remote diagnosis and treatment.However,due to the limitation of communication bandwidth and storage space in the telemedicine system,it cannot satisfy the ever-increasing storage and transmission of medical data.Therefore,it is an inevitable trend to compress medical images.Wavelet transform has become a research hotspot in the field of image compression by virtue of its excellent time-frequency localization performance and the characteristics of multi-resolution characterization of images.This thesis mainly focuses on the medical image compression based on wavelet analysis.It realizes the simulation and analysis of the algorithm through MATLAB platform and has achieved certain research results.Firstly,the background meaning of the subject research and the development history of image compression coding technology at home and abroad are explained.Then the relevant knowledge of medical image compression is explained,including the basic principles of medical image compression,the classification of compression methods and the commonly used image compression methods.It briefly describes the evaluation standards of medical image compression quality and the international standards of image compression.Secondly,a brief overview of the relevant theories of wavelet analysis is explained,including the basic concepts of wavelet transform as well as its inverse transformation requirements,the idea of multi-resolution analysis and the principle of Mallat’s decomposition and reconstruction.Then the theory of wavelet transform is applied to actual images in compression,and the characteristics of wavelet coefficients,the number of wavelet decomposition stages and the way of signal extension are discussed.In-depth study of image compression coding ideas based on wavelet transform,and in-depth analysis and discussion with the EZW algorithm and SPIHT algorithm based on wavelet transform as the key research content,detailed introduction of the coding principle and implementation process of the two,and analysis of the two In the coding process,the problem of excessive threshold value in the EZW algorithm and the problem of repetitive scanning in the SPIHT algorithm are proposed respectively to improve the coding efficiency.Finally,the compression coding of medical images is realized through MATLAB.Experiments have proved that the improved algorithm improves the PSNR value of the reconstructed image to a certain extent and has better image restoration quality than the original algorithm.