Remote surveillance with reduced transmission overhead

We present a prototype for remote surveillance aiming at reducing the bandwidth requirements without compromising the reliability. The system consists of a network of off-the-shelf proximity sensors and a point-tilt-zoom (PTZ) camera. The camera captures video when an interrupt is received by one of the sensors. A remote server controls the operation of sensors and the camera, and is capable of receiving the interrupts generated by the sensors and the videos captured by camera, through a wired or wireless network using suitable protocols. The remote server uses a two-stage algorithm to reduce the amount of data to be transferred to the main server in the control room. First, the camera is active only when an intrusion is detected, and remains idle for rest of the time. This not only reduces amount of the captured data, but also extends the battery-life of the camera. Secondly, the remote server processes the video captured by the camera to verify if an intrusion did actually occur. If it is found that the alarm was false, the video is not transmitted to the main server and is discarded. This allows further reduction in the amount of data to be transmitted, which subsequently reduces bandwidth and power requirements of the remote monitoring devices.