| As the rapid development of Internet technology, the trend of application of Geographic Information System (GIS) is network .It involve a lot of image documents in the application of GIS whose feature is mass data and complication of data structure. So the storage and transmission of information has become the bottle neck of informational share. It is key of application of GIS network to research and work out an efficient technology of data compression. In this paper, aimed at the feature of GIS remote sensing image and based on the theory of Shannon noiseless encode, we delete the 2 lower bit so that the entropy of the GIS remote sensing image is descended. In order to increase the compression-rate, after analyzing some encode methods, we pose suggest Quadtree-Arithmatic encode. This encode method can reduce the redundancy of data and bits and makes the compression-rate increase above 2 times than general encode method do. When we decompress the image, in order to compensate the 2 lower bit information losing as compressing, according to a regulation, we pick up the fringe eigenvalue of image to close in the edge curve. Then based on the theory of imaging intervolve, we get the rebuilding image when we handle each pixel of the compressed image. By the process above, the PSNR of decompressed image go beyond 40 and reach the level of lossless compressed image. I It is proved that the compression-rate of remote sensing image is increased and at the same lime it抯 quality does not decline when we apply this method to compress image, as long as we rebuild the image when it decompressed. It accord with the request of application of GIS. So this method is an efficient technology of image compression.
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