A Calibration Method of Camera System for Detecting Multi Objects(Seeds) in Close Range
近距离多目标（种子）检测中摄像机系统的标定方法

While detecting the property of seed metering device based on computer vision, adjacent objectives are possible to be covered each other, and faster detecting speed is required. In this paper, by analyzing the feature of camera and flat mirror, a calibration method of camera system that is only composed of a single camera and a flat mirror is proposed, and the calibration model of this camera system is expounded in detail. Therefore, the camera system that is only composed of a single camera and a flat mirror can not only raise speed of grabbing image but also spare memory of computer so that the detecting speed is raised. Meanwhile, applying the map relation between image points and special points, an algorithm of reconstructing special point is also given. The calibration method is testified on the experimental table of seed metering device, results show that not only this system can detect overlapping and lost of seeds, but also error is less than 1mm, and the adhesive tape that is used in detection is completely replaced.