A web-cam based vision system for performing image processing in real time in a restricted environment is presented. A color based image segmentation algorithm is the fundamental part of the system. Algorithm efficiency was very important due to hardware limitations. This led to a simple and cost-effective vision system that is able to detect and identify several mobile robots through successive frames. The main achievements of the presented system can be described as robust object detection under relative constant illumination and sufficient refresh rate at image processing to evaluate position and direction of movement of target objects with a rough idea of speed.