Outdoor Scene Synthesis in the Infrared Range for Remote Sensing Applications

This paper deals with a method of representation of landscape for the simulation of the behavior of an outdoor scene in the thermal infrared range, from 3 to 14 μm. The scene and objects are modeled in 3-D at very high spatial resolution of half a meter or so. The mesh is adapted to reproduce all the physical phenomena and their variations, according to their relative importance. The classical facet is no longer appropriate. A new quantity is introduced: the element. The element is defined as a part of an object. It is homogeneous with respect to material constitution and energy flux balance at a given instant. The mesh representing the scene is made of the union of the elements for the period of simulation of the temperature. All computations of fluxes and temperature are made on this mesh. Sufficient accuracy can be achieved by considering the most important physical phenomena to generate the elements. Shadow effect is the most important one. Influences of other phenomena are modeled by the mean of texture synthesis. In this paper, the method to define and generate elements is exposed, and an example is given, showing the efficiency of such a method to predict surface temperature, and afterward the irradiance of the scene.

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