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Compression Of Remote Sensing Image Based On Wavelet Transform And Implemented By DSP

Posted on:2007-07-17Degree:DoctorType:Dissertation
Country:ChinaCandidate:S L ChenFull Text:PDF
GTID:1118360185989730Subject:Optical Engineering
Abstract/Summary:PDF Full Text Request
With the development of aeronautical remote sensing technology, enhancement of remote sensor resolution, and increment of the quantity of remote sensing data, transmission and storage of remote sensing data become serious problems that need to be solved at once, whereas data compression is a valid resolution to all these problems.Because remote sensing image has weak local correlation, great data quantity, and abundance detail, traditional compression methods have some limits in some degree. Having good time-frequency locality and multiresolution analysis ability, however, wavelet transform is a good image compression method. In this paper, wavelet transform and DSP (Digital Signal Processor) are adopted to implement this algorithm.Firstly, the advantage and disadvantage are analyzed between Mallat algorithm and integer lifting scheme from the point of remote sensing image compression. Integer lifting scheme is independent of convolution operation and reduces the memory requirement and algorithm complexity, which is in-place calculation and wavelet coefficients are integer. Experiments show that its calculation speed is one time faster than Mallat's, so integer lifting scheme is adopted in the thesis.Secondly, based on the parallel feature of DSP, the parallel architecture of 2-D integral lifting scheme is presented. 5/3 wavelet base is selected for DSP, based on properties of wavelet basis. The strategy of ping-pong buffer allows data transfer and wavelet transform to perform simultaneously; the method of column transform based line permits column transform in the case of a few line transform results; multiplication operations are substituted for shift operations in order to enhance the transform speed. The whole architecture is optimized in the pipelined design way to achieve higher hardware utilization and decrease the intermediate data quantity, and...
Keywords/Search Tags:remote sensing image, image compression, wavelet transform, lifting scheme, zerotree coding, SPIHT, DSP
PDF Full Text Request
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