John Hatzidimos, AUTOMATIC TRAFFIC SIGN RECOGNITION IN DIGITAL IMAGES

Abstract. The objective of this project is the development of an algorithm for the automatic recognition of traffic signs in digital images. The program An.Si. was created (from the Greek words Anagnorisi Simaton which means Sign Recognition). Up to now, many algorithms for the traffic sign detection and classification have been introduced. Extensive research is being made by major car manufacturing companies in collaboration with Universities and other institutes on real-time and automatic recognition of traffic signs, so that it can be a part of the so called “Driver Support Systems” ([7]).

Two major problems exist in the whole detection process. Road signs are frequently occluded partially by other vehicles. Many objects are present in traffic scenes which make the sign detection hard (pedestrians, other vehicles, buildings and billboards may confuse the detection system by patterns similar to that of road signs). Colour information from traffic scene images is affected by varying illumination caused by weather conditions, time (day-night) and shadowing (buildings) ([7]).

The proposed method detects the location of the sign in the image, based on its geometrical characteristics and recognises it using colour information. Partial occlusion is dealt by the use of the Hough Transform and suggestions are made for future improvements so that the robustness of the algorithm in light condition changes can be increased.