Reduction of deformations of the digital terrain model by merging interpolation algorithms

Majority of contemporary spatial information systems allow generation and visualization of the digital terrain model based on GRID type of the regular squares network. The values at nodal points for such a GRID are in most cases computed by one of the many available interpolation methods on the basis of dispersed measurement points. The commonly used solutions allow in most cases application of a selected interpolation method in a global way within the entire analyzed area, which does not secure the same accuracy of surface generated. The paper describes generation of a digital terrain model by applying a combination of interpolation methods. The criterion of method choice was dependent on the dispersion of measurement points around the GRID node. This solution allows successive complementing the resultant set of computed set with values determined with a specific error and as a result improves the accuracy of the model generated.