Image Saliency Applied to Infrared Images for Unmanned Maritime Monitoring

This paper presents a method to detect boats and life rafts on long wave infrared (LWIR) images, captured by an aerial platform. The method applies the concept of image saliency to highlight distinct areas on the images. However saliency algorithms always highlight salient points in the image, even in the absence of targets. We propose a statistical method based on the saliency algorithm output to distinguish frames with or without targets. To evaluate the detection algorithm, we have equipped a fixed wing unmanned aerial vehicle with a LWIR camera and gathered a dataset with more than 44000 frames, containing several boats and a life raft. The proposed detection strategy demonstrates a good performance, specially, a low rate of false positives and low computational complexity.