Resumo

CORTES, Alfredo  e  SORANI, Valentino. Metodología en la realización del inventario nacional forestal: ortocorreccion de imágenes digitales. Invest. Geog [online]. 1996, n.32, pp.19-31. ISSN 2448-7279.

In this work we present the methodology that was used in the forestry cartography that the Instituto de Geografía (Institute of Geography, IGG) had developed with the Secretaría de Agricultura y Recursos Hidráulicos (Secretary of Agriculture and Hidraulie Resources, SARH). We present in this first stage of the proyect the methodology used in the orthocorrection of images, showing one orthoimage processed with this methodology. This geometrical correction was achieved using about 60 ground control points per image with a root mean square error of 1.5 pixels (45m), getting a good cartographic precision for this scale work (1:250 000). The ground control points were obtained using topographic cartography from INIEG1 (National Institute of Cartography). The DTM (Digital Elevation Model) was used in the image correction. In this work we present the metodology used and an example of this technique on an image of Guadalajara, Jalisco, Mexico.