Traffic light recognition

Abstract

An automatic traffic light recognition system is proposed in this paper so that car drivers have sufficient information to make a correct decision. This in turn facilitates the construction of an ITS (Intelligent Transportation System). The proposed method can be applied to movable cameras, is adaptable to environmental variations and is proper for real‐time implementation. It consists of two phases: traffic light detection and classification. The two phases are based on color, region and border information. At the detection stage, the RGB color space is first converted into the HSI color space so as to find those regions with specific colors of traffic lights. The morphology technology is employed to remove holes and noise. Region labeling is then involved to detect candidate regions of traffic lights. At the classification stage, border detection is employed to obtain region borders which together with region colors are matching features. In this study, circle and arrow traffic lights can both be coped with. Moreover, our method is adaptable to environmental variations in numbers of lights, types of lights and time slots. Various experiments have been conducted to demonstrate the effectiveness and practicability of the proposed method.

Key words:

• intelligent transportation system
• traffic light detection
• traffic light classification
• traffic light recognition
• color identification
• environmental adaptability
• real‐time implementation

Notes

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