True Orthoimage Generation in Urban Areas
نویسندگان
چکیده
Digital orthoimage is a widely used cartographic product, either as a complement to the traditional topographic map-when the latter has not been updated-or to allow the extraction of different kinds of information. The geometric precision of an orthoimage is strongly dependent on the quality of the Digital Elevation Model (DEM) and the geometric correction algorithm used. It is well known that the results obtained with the standard procedure over urban areas, when working with high-resolution pictures, are inappropriate. So, a different approach is suggested that builds a 3-D model for the existing structures, determines the hidden parts in each image and combines (mosaics) all the orthoimages that come from different views of the same area and contribute to the generation of a product free of geometric shadows.
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