The Research Of Distinction Analysis Based On Raster Data

Abstract: With the expansion of GIS application fields and the development of T-GIS, GIS raster date is frequently used in the fields of desertification expansion, forestry virus control, fire spread, and so on. But it is very clear that there are time features on these raster data, that means their distribution are based on time line. Distinctly, due to the large amout of raster data, we can' t store all of them based on the time line when we deal with their storage and management. We must try to find a effective method to deal with these raster data based on time line, so as to not only reduce the data quantity, but also fulfill the backdating and forecast functions of spatio-temproal model.In this research, towards the requirement of the T_GIS management of raster data based on time line, we used the ASCII file, a file format of the software Arcview designed by ESRI Company of USA, as our research object, we adopt the linear quadtrees code and runlength code respectively to achieve the distinction analysis method based on raster data. After theoretical research, we used the desertification raster data of Yan-chi area, NingXia province as our experimental data, and made vertification to the method in the NingXia Yan-Chi desertification raster data management system based on that data. In this system, we achieved the distinction analysis of raster data, and this will indeed make some positive contributions to the spatio-temproal management of GIS raster data.