基于视觉的增强现实运动跟踪算法

Motion Tracking Based on Vision on Augmented Reality

增强现实系统不仅具有虚拟现实的特点同时具有虚实结合的新特性。为实现虚拟物体与真实物体间的完美结合 ,必须实时地动态跟踪摄像机与真实物体间的相对位置和方向 ,建立观测模型 ,进而通过动态三维显示技术迅速地将虚拟物体添加到真实物体之上。然而目前大多数增强现实系统的注册对象均为静止物体 ,运动物体的注册跟踪尚且很少有人涉足。该算法通过标志点的光流场估计真实环境中运动物体的运动参数 ,根据透视投影原理和刚体的运动特性确定摄像机与运动物体间的相对位置和方向 ,实现增强现实系统的运动目标跟踪注册。该算法构架简单、实时性强、易于实现 。

One of the key techniques for augmented reality is registration. In order to overlay virtual objects on the real word at the right positions and orientations, the accuracy of registration is of most importance. In most of the current augmented reality systems, the real objects are static,thus little attention is paid to dynamic object tracking. An algorithm is proposed for estimating 3D motion parameters of a real object using optical flow of markers. According to the motion equation of 3D rigid body and the pinhole model of the camera, the relative position and orientation between the camera and the dynamic object can be obtained. The algorithm has a simple structure,requires only a single CCD camera and a few markers with different colors. It effectively extends the application areas of augmented reality systems.