Infrared Point Target Detection with Fisher Linear Discriminant and Kernel Fisher Linear Discriminant

It is a challenging task to detect point targets from an infrared image. Recently, the pattern recognition theory has been used to detect targets. The principal component analysis (PCA) has gained success in this field. We propose a linear subspace detection method based on Fisher linear discriminant (FLD) in this paper. If we consider images are made up of target class data and background class data, the target detection problem can be translated into a two-class classification problem. The FLD as one of pattern recognition algorithms can be used to find potential targets from image background. After classification by FLD, a map function, Gaussian map function, is developed to generate detection images in which the larger target-to-background contrast is obtained. FLD is a linear detection method without taking the higher-order statistics of image data into account. To improve detection performance, we extend this detection method to its nonlinear version, kernel FLD (KFLD) detection. Because the nonlinear subspace is capable of capturing the part of higher-order statistics, the better detection performance can be achieved. The well-devised experiments verify that KFLD detection outperforms FLD and other common used detection methods.