Figure 1. Block Diagram of Real Time Video Tracking System

It is now well accepted that vision will play a major role in both supervised and unsupervised operations for the automation of several security activities. The purpose of video tracking is to stabilize the line-of-sight (LOS) of a camera to the actual LOS of a moving target, such as a moving human. Video tracking, by definition, is to track the moving objects by some typical features, and monitor their activities by image sequence taken the video cameras. By video tracking, we can answer some questions such as who are they, what are they doing, and where and when they are acting. Video tracking system can be used in many areas such as airport, embassies, battlefield, robots controlling and even in classroom or living room. For an example, the video tracking system can be installed in airport to collect the pictures of people entering and exiting the building so that suspected terrorist can be found in the airport before he aboard the plain. Real-time information from the battlefield can improve the situational awareness of commanders and stuff. In remote education, camera can track the face of the instructor. For robots industries, real-time video tracking system can send command to robots to perform some tough tasks.

We made a plan for a wireless, pan-tilt-zoom (PTZ) camera-based video surveillance system.  The goal of this work is to realize a prototype of video surveillance system, which can provide the high-end video tracking functions based on a mobile server platform.  The above mentioned video tracking functions include; (i) flexible camera position by wireless video and data transmission, (ii) wide range of search areas by multiple PTZ cameras, (iii) extracting a suspicious person out of complicated background, such as crowd of multiple people and non-stationary background, and (iv) dynamic analysis of the trajectory of a suspicious person by the inter-camera object handover technique.

This system consists of several modules as shown in Figure 1. The first module is image acquisition module. This function is completed by PTZ camera. The next stage is digitization. Since computer deals with digital signal, the NTSC video signal has to be digitized before they are input to the computer. The digitized image will be input to computer for image processing. The Image processing module includes three sub-modules such as Background Generation module, Segmentation module and Tracking module. The main algorithm of this system will be completed in these three modules. Some background information taken by PTZ camera is stored in the Background Generation module. Then the difference between the input image and the background image is computed to detect the moving image. This method is known as background subtraction. The moving image is segmented by Segmentation module. Only segmented image will be send to tracking module. This decrease the data amount, thus save computational time. Tracking module will detect the position and size of the object. It will generate a command sending to computer through communication port such as RS485 data communication port. Then camera can move according to the command to track the object automatically. Figure 2 shows the hardware component of the system. The camera control software is written in Visual C++ with Panasonic command protocol.

Figure 2. Hardware block diagram of wireless video tracking system.

No publications currently available for this project.