Photoclinometry is a method for extraction digital elevation models from one single image on the basis of shading – in many cases it is also called shapefrom - shading method. The tested program ISIS ...is capable of making interactive photoclinometry. ISIS is developed and used especially for photographs of different space objects. It is an open-source program, which works under the Linux operating system. In this paper, the installation, handling and capabilities of ISIS are described. In detail a module for photoclinometry is described and tested. The test is made on a photograph of a part of planet Mars. The results of photoclinometry depend greatly upon parameters of photoclinomety (albedo and the photometrical function of surface) since a small change of a parameter can cause a big change in the produced DEM. With photoclinometry very accurate DEMs can never be obtained. From the test it can be concluded that results gained with photoclinometry can be used for research or orientation purposes, but never for geodetic precision. One field of possible usage in Slovenia is the old-archive CAS images of snow-covered areas.
Four methods for extracting height data from photographs made with active or passive sensors are described: clinometry, stereometry, interferometry, and polarimetry. Clinometry is described in ...detail. It is a method which extracts height data from just one photograph with the use of the shape-from-shading principle. Digital terrain models of planets Mercury, Venus and Mars and smaller bodies of the Solar system are described. Emphasis is given on the use of the clinometry.
The book presents a method to create a land cover map from lidar data (elevation, intensity and standard deviation of height). The intensity of the observed object depends on many factors and is ...therefore not easy to interpret. With careful study of the problem and implementing various improvements we managed to distinctively classify categories of grass, agricultural fields and asphalt. We used standard deviation of height to differentiate trees and buildings, because this was not possible using intensity data alone. On the basis of independent lidar data a high quality three dimensional land cover map of local area has been successfully generated. It distinguishes five basic categories, although more detailed sub-categories could be introduced if necessary. Once the methodology is determined, products can be generated fully automatically, with minimal effort and costs. The resulting maps are of very high positional and thematic accuracy with numerous advantages for local studies.
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