手工摆放的平行摄像机阵列所拍摄的多视点立体图像往往会产生垂直视差. 为了消除多视点图像的垂直视差, 必须进行多视点图像的校正. 提出一种简单有效的多视图校正算法, 并基于该算法构建了自由立体显示系统. 应用多线程进行摄像机软同步以及后续的实时优化. 当摄像机图像的上传分辨率为1 280×960、上传速率为25 帧/s、目标3D 显示器的分辨率为1 920×1 080 时, 采用双线性插值, 可达到20 帧/s 左右的显示速率; 若采用复杂度更低的插值方法, 则可达到20 帧/s以上的显示速率. 该算法实现了8路摄像机实时校正和立体显示的3D电视系统.
Multi-view images captured by a parallel multi-camera array manually placed tend to produce vertical parallax. To eliminate vertical parallax, the multi-view images must be rectified. This paper presents a simple and effective algorithm for multi-view rectification, and builds a stereoscopic display system based on this algorithm. A multithread technique is used to achieve soft synchronization of the cameras, and to perform real-time optimization. When image resolution is 1 280×960, the upload rate is 25 frame/s, and the target 3D display resolution is 1 920×1 080, the display rate of the system can reach 20 frame/s by using the bilinear interpolation. If interpolation methods with low complexity are used, the display rate can reach more than 20 frame/s. A 3DTV system with real-time rectification of eight cameras and stereoscopic display is built by using the proposed algorithm.
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