A Study Of The Remote Sensing Image Compression Technology For The Digital Photogrammetry

As the full digital photogrammetry system widely used, digital photogrammetry becames the main mode of the photogrammetry production. The large amount of remote sensing image data is the primary data source of the digital photogrammetry system,.And it turnes into one of the most important problems faced by digital photogrammetry. As a powerful tool for analyzing non-stationary signal, wavelet transform has flexible time-frequency analysis window. It became a research hottopic in the field of image compression. In this paper, with the support of related projects, a remote sensing image compression technology based on wavelet transform and the initial program that applying the compression technology to the digital photogrammetry production has been studied mainly. The specific results are as follows:1. The characteristics of image wavelet transform have been verified by experiment. And the advantages that applying the wavelet transform to the field of image compression have been studied.2. Compared with the ordinary people and landscape images the characteristics of the remote sensing image has been analyzed by statistic method, the difference between the first generation wavelet transform and the integer wavelet transform has been studied, which provided a theoretical basis and directional guidance for the study on image compression based on wavelet transform.3. The Embedded Zerotree Wavelet coding algorithm that based on wavelet transform was studied. The feasibility and the advantages of the EZW coding algorithm has been proved by experiment that compared with standard JPEG algorithm .And combined with the characteristic of the remote sensing image, the EZW algorithm was improved according to its disadvantage. The feasibility and effectivity of the improved algorithm was verified by experiment.4. The relationship between the image information and point feature and point feature extraction has been analyzed. A method was put forward that evaluating the quality of remote sensing compression image with the point feature. The impact of the remote sensing image lossy compression on point feature extraction was studied by analyzing and comparing the point feature extracted from the decompression image that compressed under different compression ratio.5.The transmission and storage process of the image data as source material, intermediate data and production data in the digital photogrammetry network production process has been analyzed. And a image compression scheme for the digital photogrammetry network production was proposed based on this.