红外热成像系统由于具有全天时观测能力而得到广泛应用。为了测试和评估高分辨率红外热成像系统的性能,需要大量多种成像条件下的热红外影像作为输入数据源。为获取真实可信的地面热红外仿真图像,提出了一种针对复杂地形的热红外成像模拟方法。该方法综合起伏地表的地形、光照、遮蔽和邻近地域辐射等因素,系统研究了三维地表热辐射的产生和传递机理。利用光学遥感影像和数字高程数据,生成了一天中不同时刻的地面热红外图像。结果表明:该方法生成的24 h序列图像,符合实际地表热辐射场的日变化规律,从而为可见光图像制备红外基准图提供了一种有效途径。
Infrared thermal imaging systems are widely applied with the ability of all time observation. In order to test and evaluate the performance of high-resolution infrared thermal imaging systems, a large number of thermal infrared images in different imaging conditions are needed as input data sources. To obtain credible thermal infrared simulated images of ground, a TIR imaging simulation method for complex terrain was proposed. Combined with factors of terrain, light, shadow and radiation from neighborhood on relief surfaces, the generation and transmission mechanism of thermal radiation on 3D terrain surface was studied systematically. Thermal infrared images of terrain surface on different time in a day were simulated by using optical remote sensing images and DEM data. The results indicate that, the TIR image sequences made by this method accord with the daily changing law of thermal radiation on ground, therefore, an effective way of producing IR reference images by visible images is provided.