Change detection and background extraction by linear algebra

Change detection plays a very. important role In real-time image analysis, e.g., detection of intruders. One key issue is robustness to varying illumi nation conditions. We propose two techniques for change detection that have been developed to deal with variations in illumination and background, wit h real-time capabilities. The foundations of these techniques are based on a vector model of images and on the exploitation of the concepts of linear dependence and linear independence. Furthermore, the techniques are compatible with physical photometry. A deta iled description of the proposed detector and three state-of-the art change detectors is also provided. For the purposes, of comparison, an evaluation procedure is presented consisting of both objective and subjective parts. This evaluation procedure results in a final performance value for each det ector analyzed.