关键词: 光笔, 实时跟踪, Camshift跟踪算法, 红色滤镜, 跨平台的计算机视觉库（OpenCV）

Abstract: To realize the real-time tracking of the shoot point from light pen，the Camshift tracking algorithm is chosen，but it is difficult to track the point with dynamic and complicated background and in case that there is similar color with the shoot point.So，an improved method is proposed.Firstly，a red filter which weakens the effect of background，and makes the object prominent is introduced to improve the effect of color extraction based on Camshift algorithm.The red filter makes the algorithm overcome disturbance of the background color，and makes the tracking of the shoot point with high real-time performance and strong robustness.Then the automatic tracking of the shoot point from light pen is realized by changing the manner of selecting region.Finally，the real-time tracking of the shoot point from light pen using OpenCV is realized.The experimental results indicate that color object is efficiently tracked even with dynamic and complicated background by the new method which is presented.

Key words: light pen, real-time tracking, Continuously adaptive mean shift（Camshift）, red filter, Open Source Computer Vision Library（OpenCV）