Because there are few kinds of available DEMs now, those DEMs are very often extracted with appropriate interval from topographic maps with contour lines or stereoscopic images. Ortho-images are usually made using DEMs and images with orientation elements. But nowadays they are more frequently used in GIS (Geographic Information System), because they can be overlaid directly on many kinds of maps in the system. It is well known that ortho-images are necessary to make stereoscopic images of any B/H ratio, or bird’s eye view images from any view point. This method can be realized by modifying the software of a digital photogrammetric system slightly. Because two images of the same are used in this method, some image corrections, such as partial replacements and arithmetical calculations on images, can be carried out to make a fine output of an ortho-image. In this paper, a new method is proposed, which produce an ortho-image from streoscopic images directly. Tel : (81)-720-66-5390 Fax : (81)-720-66-8380Įmail : ortho-image is usually made using both an image and a DEM (Digital Elevation Model) of the same area. An ortho-image production method from stereoscopic imagesġ-79-1, Kitayama, Hirakatashi, Osaka, 573-01, Japan

Ortho extract software