Retrieval module to choose satellite images by considering the demand of disaster mitigation

To shorten the time of RS image pre-processing, this paper considered to realize the automation of choosing image process before downloading. RS images are big files, for example, one scene of CBERS-CCD multi-spectrum image can be more than 100 Mb. The searching methods on the satellite data issue webpage are limited, and the searching results still need more time to choose which images are worth studying. This paper took the choosing process of CBERS images as example, and broke through the conventional searching methods in, and then built the retrieval module of choosing CBERS images by considering the demand of disaster mitigation to help the users quick and effective find the aimed data to study. Firstly, ordered a certain time and space range in the CBERS issue Webpage to search image, built a scene-center database from the information of the search results, such as PATH, ROW, longitude, latitude etc., from which the standard scene-center point´s matrix was calculated according to the satellite imaging character. Take the standard scene-center point´s matrix as normal imaging scene-center points; screen out the scene-center points in a threshold range. Secondly, in order to obtain the better result of change detection, two choosing rules about imaging time were founded and actualized by Matlab. In the end, the chosen points were overlaid with the isoseismals, the spatial analysis method `identity´ is applied to get the priority download list of CBERS images.