Digital signal processing is used in many fields such as space exploration, medicine, geology etc. The main objective of this paper is to demonstrate the ability of image processing algorithms on embedded computing platforms .It describes a road sign recognition system based on an embedded system that reads and recognizes speed signs and also controls the speed of the moving vehicle. The paper also describes how to deal with numbers using image processing techniques based on shape and dimension analysis. Colour analysis also plays an important role in road sign detection.Raspberry Pi is the main component for the implementation of this system, as it has built in capabilities. It is a computer vision based system for traffic sign detection, tracking, and recognition in real time. The signs on the road side are captured with the help of camera interfaced to the video port of raspberry pi. The captured image is then compared with pre-defined road signs. Dimension analysis is performed with the help of K nearest algorithm. Upon obtaining the best match, the corresponding speed limit in the detected image will be sent to raspberry pi and it generates a pulse width modulated signal in order to control the speed of vehicle accordingly.