A dynamic background extraction method for indoor intruder detection

With recent increases in criminal activity, research and development efforts are required for detection of intruders. This paper proposes an element technique for developing a cheap intruder detection system with high performance. The following three functions are developed in this study. (1) The system can deal with smooth changes of illumination, including movement of the light source. (2) For a slowly moving intruder, the region of presence is clearly detected. (3) For an intruder pausing his movement, the region of presence is clearly detected. Functions (1) and (2) are apparently contradictory. The basic idea of the method is to detect the region of presence of the intruder based on the difference image between the background image without the intruder and the present input image. The crucial point then is how to update accurately and simply the present background image, and there has been no method that realizes the above three functions at the same time. In contrast, we realized these functions by an approach in which weighted averaging is not applied to the detected intruder region and its boundary in the background image. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(12): 61–76, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20424