Motion detection

From ArticleWorld

Motion detection is connected with procedures or methods by which motion can be identified. At present, Motion detection sensors are easily available and they can easily detect sound and produce an alarm or switch on an image-recording device. Presently there are motion detectors that employ cameras connected to a computer to detect certain objects that might be moving. Most motion detection units employ a simple algorithm for verifying motion detection through a fixed camera. It compares the current image with a reference image and simply counts the number of different pixels. By verifying if, there are changes between the two it identifying if there has be any instance of movement. Since images naturally differ due to factors such as varying lighting, camera flicker, and CCD dark currents, pre-processing is used to reduce the number of false positive alarms. Depending upon the complexity and nature of the object that is to be guarded, more algorithms that are complex are used to detect motion when the camera itself is in motion. When the motion of a specific object must be detected in a field containing other movement which can be ignored certain complex calculations are carried our by the motion detection device. An example can be an expensive painting that is protected by a motion detection device in an art gallery surrounded by visitors. Increasingly more and more complex motion detection devices are being developed for detection, surveillance, and policing. Speed cameras set up at traffic points are used to catch speeding drivers even when no police personnel might be around. With increase of attacks on mass transit spots like airports, rail and bus terminals, motion detection tools are increasingly being brought in for crime prevention and early detection. It is suggested that use of such sophisticated motion detection devices may be a suitable deterrent against potential violators. However, human rights activist insist that such technologies are undemocratic and violate basic human right to privacy.