Research On Vectorzation Of Land-use Basic Map

The early land_use basic map is hand drawn on paper ,and it can not only be preserved inconveniently, but also difficult to compare with current land_use basic map which is vectorgraph and computer drawn,to get the information of land_use changing. In this paper we analysed the characters of scaned land_use basic map, and raster to vector conversion of land_use basic map is also discussed.A valuable vectorization flow diagram based on the characters of land_use basic map is presented, and key techniques such as color separation, semiautomatic linear objects extraction ,noise suppressor and contour optimization algorithm are discussed. Several techniques of color separation is introduced ,and K-means clustering is adopted; Basic characters of linear objects is analysed, and a new algorithm of direction changed tracing method for linear objects skeleton based on direction estimate is produced in the paper, which can not only efficiently extracts the information of linear objects such as bridges and roads, but also eliminates the disturbing effect of linear objects and noises; Because plots are often rounded by redundant rims, mathematic morphology is introduced and efficiently resolves the problem ; A consistent contour optimization algorithm based on three-colour points is also presented ,which efficiently resolves the mutual contour line unification problem of conterminous plots.The experiment result demonstrates that the algorithms perform well.