Abstract: In recent years, optical touch system is a gradually rising solution of touch system, and it recognized the touch-point based on the method of mass tracking from computer vision recognition. The paper put forward a new method applied to contacts recognition of optical touch system, first, it carves up the image gathered by the camera by two thresholds and extracts the contours, and then, it computes the minimum external rectangular of the bright spot, at last,it eliminates the invalid contacts based on the area and the aspect ratio of the features outlines. This method using OpenCV1.0,on the premise not affecting handling efficiency basically,realizes the accurate contacts recognition.

Key words: Double threshold segmentation,Features outlines,Optical touch system,Contacts recognition