Test uporabnosti fotoklinometrije za monoslikovno restitucijo : Test of Applicability of Photoclinometry for Single Image Restitution

Abstract

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.

Keywords

• remote sensing
• photoclinometry
• digital elevation model
• program ISIS
• daljinsko zaznavanje
• fotoklinometrija
• digitalni model reliefa