Adaptive Ship Detection for Single-Look Complex SAR Images Based on SVWIE-Noncircularity Decomposition

In this paper, we present an adaptive ship detection method for single-look complex synthetic aperture radar (SAR) images. First, noncircularity is analyzed and adopted in ship detection task; besides, similarity variance weighted information entropy (SVWIE) is proposed for clutter reduction and target enhancement. According to the analysis of scattering of SVWIE and noncircularity, SVWIE-noncircularity (SN) decomposition is developed. Based on the decomposition, two components, the high-noncircularity SVWIE amplitude (h) and the low-noncircularity SVWIE amplitude (l), are obtained. We demonstrate that ships and clutter in SAR images are different for h detector and h detector can be effectively used for ship detection. Finally, to extract ships from the background, the generalized Gamma distribution (G Γ D) is used to fit h statistics of clutter and the constant false alarm rate (CFAR) is utilized to choose an adaptive threshold. The performance of the proposed method is demonstrated on HH polarization of Alos-2 images. Experimental results show that the proposed method can accurately detect ships in complex background, i.e., ships are close to small islands or with strong noise.

Real-Time Auto-Light System for High-Speed Camera

In order to obtain stable and high quality image from high-speed camera in real time under different environment, the system hardware based on TMS320DM642 is designed and a complex control method is proposed to realize auto-light control rapidly by harmonizing alterable diaphragm and camera exposure time. The algorithm of the auto-light system mainly consists of two parts: the analysis of brightness information based on Variance weighted information entropy, camera exposure time control and alterable diaphragm control based on data analysis. The project results show that the algorithm has rapid convergence and strong adaptability, and the system can realize large-scale and real-time auto-light at different conditions.