The recognition of traffic speed limit sign in hazy weather
Gang Yan, Ming Zhen Yu, Shuo Shi, Chao Feng · Journal of Intelligent & Fuzzy Systems · 2017
Hazy weather affects drivers’ sightline seriously and causes a high potential safety hazard. This paper proposes a novel approach for recognizing the speed limit sign in hazy weather. It consists of three major modules: haze removal, speed limit sign location, and sign recognition. In haze removal, this paper proposes to dehaze image with the dark channel prior. The speed limit sign is located by Histogram of Oriented Gradient (HOG) feature extraction and Support Vector Machine (SVM) classification and is recognized by the seven layers Convolutional Neural Networks (CNN). Experimental results show that the proposed method has better performance than the state-of-art dehazing methods and the processing time is also reduced. The recognition rate of the speed limit signs is 98.51% that is better than the human performance, and the classifier can recognize the speed limit sign with rotation, shift, scale and other distortions.