Physics-Based Infrared Terrain Radiance Texture Model.

This report develops a physics-based semiempirical model for predicting the texture of an infrared IR image of terrain areas including soil, grass, and forest canopies. The model is based on an empirical determination of the relationship between the standard deviation and correlation length of the terrain radiance variations in an IR image and the average value of the radiance in the image. The average value of the terrain radiance is then theoretically predicted by the WESTHERM terrain radiance prediction model in terms of local terrain and weather conditions and in terms of the time of day. In this way, the diurnal variation of the standard deviation and correlation length of the radiance or brightness temperature can be predicted for specified terrain and weather conditions.