The Research Of X-ray Image Compression Algorithm On Wavelet Transform

Telemedicine is a common method for the special medical services of the remote areas, but the data of the medical image is very large, it brings great inconvenience to the transmission and effective and timely diagnosis of doctors. In order to achieve economic storage and fast transfer of the images, medical image should be compressed before it transmitted, The traditional image compression method is used mainly from the Angle of information theory, unconsidering visual characteristics, it can not satisfy the requirement of people on the compression rate and subjective quality. This paper mainly study the wavelet transform and how to realize the grade coding and transmission of wavelet coefficients, using the image wavelet coefficient of correlation, thus realize image asymptotic transmission technique.The paper first discusses the prospect of medical image compression and the development stage of the wavelet transform, image compression method and technique, image evaluation criteria, focuses on the wavelet transformation. Wavelet efficient were coding, EZW coding, SPIHT coding, SPECK coding. Finally making a few compressions on the traditional medical image, based on 9-7 filter integral wavelet transform, after that, the high frequency part uses SPIHT coding, while the low frequency part adopts DPCM prediction coding.An experimental platform by Matlab 7.0, X-ray image by digital radiographic was simulated. Compare with the traditional algorithm. Experimental result shows that the improved algorithm in image peak value signal-to-noise ratio and coding or decoding time is superior to the traditional medicine compression algorithm.