Abstract: The creation of virtual camera is a key technology in the virtual advertisement system.This paper proposes a method of creating a virtual static camera.Firstly，detect the feature points in the video frames，next calculate camera’s inner and external parameters according the correspondence of feature points both in the image coordinates and the world coordinates with the camera calibration technology，then set the virtual camera’s model view matrix and projection matrix on OSG with the parameters calibrated.Finally，render the virtual scene under this virtual camera and blend the rendered results into the right positions in the video frames.The experiment proves this method sample，effective and easily produced.

Key words: camera calibration, virtual camera, model view matrix, projection matrix

摘要： 虚拟摄像机的生成是虚拟广告系统中一项关键技术，提出一种静止虚拟摄像机生成方法。首先，在视频图像中自动检测比赛场地的特征点，然后根据特征点在图像坐标系与世界坐标系上的匹配关系，利用摄像机定标技术计算出真实摄像机的内外参数，接着把摄像机的内参数和外参数分别转换为虚拟摄像机的视点转换矩阵和投影矩阵，最后在此虚拟摄像机下对虚拟场景进行渲染，把渲染出的图像插入到视频中。实验结果表明该方法简单、有效、易实现。

关键词: 摄像机定标, 虚拟摄像机, 视点转换矩阵, 投影矩阵