Passive touch system and method of detecting user input

摘要

A method of tracking an object of interest preferably includes (i) acquiring a first image and a second image representing different viewpoints of the object of interest; (ii) processing the first image into a first image data set and the second image into a second image data set; (iii) processing the first image data set and the second image data set to generate a background data set associated with a background; (iv) generating a first difference map by determining differences between the first image data set and the background data set and a second difference map by determining differences between the second image data set and the background data set; (v) detecting a first relative position of the object of interest in the first difference map and a second relative position of the object of interest in the second difference map; and (vi) producing an absolute position of the object of interest from the first and second relative positions of the object of interest.