الملخص

The compression technique is an optimal solution for decreasing the amount of information sents out from satellites to earth station with rate transmission. In this paper, a study for the application of embedded zero tree wavelet (EZW) in image compression is incorporated. The study is implemented using the image processing toolbox of Matlab ver 6.5 .The performance of the proposed algorithm is executed and tested using the standard image of Barbara with size 512×512 pixels in bmp format. Different threshold values are used in the proposed algorithm to specify the compression ratio CR. The quality of reconstructed image is measured in terms of PSNR .The recorded results show that there are a trade off between the PSNR and CR and depends on the type of used image .In this work the extraction of the results are focused on two types of local area satellites images .The first image is the Mosul dam area with simple and limited topography .The second image is the Singar area with different and difficult topography .The results show that at threshold of 16 , the CR is a round 1:60 with PSNR more than 34 dB ,for the tested image .