Research On Video-image Stabilization And Moving-object Tracking In Ship Monitoring And Control

According to the particularity of ship operating environment and the special requirement of ship monitoring and management, the main purpose of this research is to accomplish image stabilizing for fluctuant shipborne video and finish interesting target tracking based on the former. In the process of ship monitoring, form a host ship's view to observe outside objects, a very important common characteristic hidden in every frame can be found that the horizontal line information always appears in some area and shakes continuously due to the sway of host ship. If some ship target appears in the distance, the horizontal line will be separated into two line segments. So, by taking full advantage of this feature, the relation between video image stabilization and video target tracking was found out. Then, make the use of relevant mathematical tools and video processing method to make video stabilizing, and at the same time to achieve target tracking nearby horizontal feature line.In the process of video image stabilization, after analyzing relative models about shipborne video-image system to obtain the reasons for interframe blur and insideframe blur, and deduce the relation between parameter variation of feature line and ship motion. Then, adopt the combination of wavelet transform and Hough transform to complete identification and extraction of feature line and consult the relation between feature line equation and global coordinate system to finish motion estimation of fluctuant video sequence. According to motion estimation result, adopt self-adaptive smooth filter to make the shipborne video image motion divided into three types, i.e., subjective scanning motion, objective scanning motion and high frequency random motion. The first motion needs to be protected by filtering out, while the other two types need to be compensated separately. So, use image geometry transform to compensate the high frequency random motion, and use feedback of video platform to compensate the objective scanning motion. By the two kinds of compensation for video image motion, video stabilizing is finished, which is so called dual compensation video image stabilization.In the process of video target tracking, a method that uses a reference point to replace the target object for tracking is adopted. Firstly, according to the corresponding conversion relations between image space, parameter space and line segment space, use the Hough transform to realize dynamic grouping and endpoint integration for the points of feature line, and extract the segments and its' endpoints, calculate the conference point's coordinate in image space. Then, use discrete Kalman filter to estimate the conference point's trajectory and calculate its position in every frame. Finally, use the feedback of video platform to make the moving target always be within the alert area, which is set in advance, and finish the automatic tracking of target.In the view of engineering application, the processing of video image stabilization is a premise and basis for the realization of target tracking, and target tracking is an application and purpose for video image stabilization. According to the feature of ship monitoring environment, this thesis makes a well combination for video image stabilization and target tracking by the processing of identification and extraction for feature line.