Method of adaptive and combined thresholding for daytime aerocosmic remote detection of hot targets on the earth surface

摘要

A method of thresholding for remote detection of hot targets on earth surface based on radiometric data of spaceborne or airborne imaging optoelectronic sensors is carried out by firstly co-registering of simultaneously obtained multispectral data of an image scene containing expected hot targets in an ambient background. A preliminary detection of bright spots in the Mid-Infrared (MIR) channel is then performed by an adaptive thresholding in a moving window procedure for each pixel with its radiometric value compared to the radiometric mean value of all pixels located in the moving window. A combined thresholding procedure is then applied which consists of several successive processing procedures performed for each selected bright spot providing fixed and adaptive thresholding operations in the Thermal Infrared (TIR) channel in combination with a threshold operation using a ratio of the radiometric data in the MIR channel to the radiometric data in a Visible/Near Infrared (VNIR) channel.