Processing of Vectorization Error to Scanned Map based on Least Squares Collocation Method

摘要

Screen digitizing is a common way of map-digitizing. In the procedure, some systematic errors such as map distortion and resolution of scanner will influence the digitizing result. the affine transformation is a common method that realize the transformation from raster data after scanning to vector data . we find that this transformation only based on least squares can only eliminate the entire deformation, but the local deformation of map and resolution of scanner in the process of scan aren't eliminated. The author commends to use least squares collocation. By the method , we can calculate adjustment parameter and evaluate the influence of local signals at the same time, can eliminate or diminish the influence of these errors, then the precision of data will be improved, through some study and analysis of a instance, we conclude that the least squares collocation is an efficiency method to advancing the precision of scan digitizing.