A New Image Compression Method Based On Wavelet Transform And Human Visual System

The paper focuses on the image compression and coding scheme based on wavelettransform and human visual system(HVS)and its realization by programming．The contents of the paper covers as follows: First,the paper introduces the research background of the subj ect and the relevantthings of image compression,including the basic theories and methods in common use of image compression．By analyzing and comparing,the image coding scheme based ontwo—dimension(2一D)discrete wavelet transform(DWT)was chose which was used much more and could lead to better results,then the contents of research was determined as the image compression and coding based on wavelet transform combined with human visual system． Then it clarified the reasons why DWT was chose as the image compression scheme and why edge detection was made,and reasoned the feasibility of the image scheme．Because of its time—frequency localized properties,wavelet transform catches people'S eyes and makes its contribution in the field of image compression．Starting with the time—frequency localized properties of wavelet transform and its coherence with human visual system,the paper aims at researching an image compression scheme with universality based on wavelet transform． During the image compression based on wavelet transform,according to thetime—frequency localized properties and concentricity of energy distribution of wavelet．transform,we chose wavelet bases adapt to image compression,and determined thelevels that image should be transformed,and determined the threshold for quantification and schemes of quantification and regrouping coefficients．In addition,considering that sub-images of high frequency contains much information of edges and human visual system is sensitive to the edges,SO we detect edges with the wavelet method to reserve useful information of image and enhance the quality of the reconstructed image． The paper takes the theoretic base of wavelet transform which was highly praised as"mathematic microscope",and make full use of statistical properties of image and human visual system,implements the image compression,finally good experimental results were achieved,such as high quality of image,low complexities of computation,small quantity of computation,short time of coding and decoding and provided with universality． In the end,it discusses the developmental tendency of image compression andsome existing problems of the methods of image compression and the wavelettransform,which would establish strong bases for the future work．...