The detection of ship targets in infrared images with sea-sky background can find enemy ships in advance and provide position indication for fire control system. Furthermore, it is also very useful in many civil fields such as fishing vessel surveillance and maritime search and rescue. Nowadays, there is still a large gap between existing ship target detecting methods in infrared images with sea-sky background and the utility. Many aspects need to be improved, such as environment adaptability and detection accuracy. According to actual application scenarios, this paper mainly researchs on the detection of medium and small ship targets in shipboard infrared images. Under this limited ccondition, it can be found that when the sea-sky line appears in the image, ship targets often appear in the area near the sea-sky line. Therefore, we only need to detect ship targets in the neighborhood of the sea-sky line. Then, the calculation amount of detection algorithm could be largely reduced for the diminution of the background interference, with an improvement of detection accuracy. In this paper, we divide ship targets detection in infrared images with sea-sky background into two parts: sea-sky line detection and ship targets detection. The main contributions are summarized as follows. (1) A sea-sky line detecting method based on chain code is designed. In this method, we firstly downsample the original image in order to reduce the image resolution and the calculation amount of subsequent steps. Secondly, edge image is generated according to vertical gradient. Then, a new chain code following method based on the characteristics of sea-sky line is used and a line detecting method based on chain code is applied to detect lines in the edge image. Finally, whether the sea-sky line exists in those detected lines will be judged. Experimental comparison shows that, our method has good adaptability to complex sea environment and high detection accuracy. (2) A ship target detecting method based on saliency analysis is realized. This method combines results of global-context saliency detection and local-context saliency detection. Futhermore, when the sea-sky line is not detected, this method also combines results of a new saliency detection method based on background prior knowledge. Experimental results show that in the application of ship target detection in infrared images with sea-sky background, our method has better detection results compared with some classi...
修改评论