Influência dos interpoladores utilizados para a geração de MDE no processo de ortorretificação de imagens orbitais

The satellite images acquisition involves geometric and radiometric deformations that must be corrected or minimized. To correct them, several methodologies and tools can be used, one of them being orthorectification, which minimizes the inclinations of the platform and provides an orthogonal projection of the images, so that reliable information can be extracted. To perform the orthorectification, it is necessary to generate the Digital Elevation Model (DEM) of the region, that will be used to correct the distortion of the terrain. In the process of DEM generation, different interpolators can be used to reconstruct the Earth''s surface. Considering the importance of the production of quality cartographic data from orbital images, the purpose of this work is to evaluate the positional accuracy of the products generated from orthorectification based on DEMs generated through the Topo to Raster, Krigagem, TIN and IDW interpolators for an IKONOS II image from Viçosa - MG, using the technical specification for geospatial data quality control (ET-CQDG) of INDE. The DEMs were generated from contour lines, hydrography and elevation points data, available in the IBGE database, with 1: 50,000 scale. It was possible to identify that, in the generated orthoimages, the interpolator that presented the best result was the Topo to Raster, reaching class C on the scale of 1: 10,000 and the worst, the IDW, reaching class D in the scale of 1: 10,000 Palavras-Chave: Interpolators, DEM, orthorectification, positional accuracy, interpoladores, MDE, ortorretificação, acurácia posicional.