Spaceborne Remote Sensing Images Based On Second Generation Wavelet Transform Compression Algorithm

Along with the development of aerospace telemetry, the resolution of on-board image also gets better, but high resolution goes with big data stream. This situation needs higher quality of data compression on-board. And because of the big disparity in aerospace telemetry between our county and the advanced in the world, there is much significance in studying the algorithm of on-board image's data compression and the implement methods.On-board image contain large amounts of information but low relativity. In allusion to this characteristic, after analyzing many kinds of compression methods, a compression method is proposed, which is based-on the second wavelet transform .Firstly, it shows the importance of research by making a framework design about the compression system of on-board image. The function modules of this architecture are analyzed, and the key techniques of the implementation of the system are discussed. Afterwards, by introducing the theory of wavelet pretreatment, it is found that there are several disadvantages in the compression system in using the traditional wavelet transform, for example, it is not conducive to lossless compression and hardware implementation .Therefore lifting scheme is used .Then, the dissertation gives a method which is fit for compression of the on-board image. Lots of experiments show the distribution character and correlation of subband of wavelet coefficients, which is useful for later coding. Next, according to modify the space tree structure, the dissertation gives a modified embedded coding method which is based on SPIHT. Finally a compression method adapted to the on-board image is proposed, and has good performance in experiment.