Visibility Simulation Technique for Support of Visual Recognition of the Landform Features

Novel technique for enhanced visual recognition of the landform features developed by spatial analysis on the digital terrain model (DTM) is proposed. The approach called “visibility simulation technique” is consisted form the following steps: (1) visibility calculation, (2) altering an azimuth and zenith angle (following the proposed algorithm), (3) generating continuous surfaces that indicate upper/lower views and relative relief, (4) visual recognition of morphological features by thematic and general cartography, as possible input for further modelling and phenomena detection. Modelling parameters are highly independent on the landform morphology where only the parameter of zenith angle needs some minor adjustments. An interesting application is generation of a comprehensive relative relief. An important auxiliary result considers improving of the DTM quality. The proposed technique was tested on the morphologically various terrains of Mars and demonstrated using a DTM produced from HRSC images of the Mars Express mission.