Hot targets enhancement for color fusion of visible and infrared images

Hot targets enhancement algorithm for the color fusion of visible and infrared images under trees and land background is presented. Opponent visual model is used to fuse and enhance the complementary information between visible and infrared in YUV space. During the process of color transfer, a crossed window of size 3 × 3 helps to locate the hot target in infrared image. When the local gray mean value of the window is larger than the global mean value of the infrared image, the center pixel is determined in a hot area. Then the V component that represents the difference between luminance (Y) and red color is increased by the ratio of the local gray mean value to the global mean value. Tests showed that this method pops out the hot targets with intense red and is effective on alerting observers to possible interested target. At the same time, the background is rendered a natural color appearance similar to a day-time color image, improves scene depth perception and increases situation awareness.