Frequency Maps as Expert Instructions to lessen Data Dependency on Real-time Traffic Light Recognition

Research on Traffic Light Recognition (TLR) has grown in recent years, primarily driven by the growing interest in autonomous vehicles development. Machine Learning algorithms have been widely used to that purpose. Mainstream approaches, however, require large amount of data and a lot of computational resources. In this paper we propose the use of Expert Instruction (EI) to reduce the amount of data required to provide accurate ML models for TLR. Given an image of the exterior scene taken from the inside of a vehicle, we stand the hypothesis that the picture of a traffic light is more likely to appear in the central and upper regions of the image. Frequency Maps of traffic light locations were thus constructed to confirm this hypothesis. Results show increased accuracies for two different benchmarks, by at least 15%. The inclusion of EI in the PCANet achieved a precision of 83% and recall of 73% against 75.3% and 51.1% of its counterpart. We finally presents a prototype of a TLR Device with such EI model to assist drivers. To show the feasibility of the apparatus, a dataset was obtained in real time usage and tested in an AdaBSF and SVM algorithms to detect and recognize traffic lights. Results show precision of 100% and recall of 90.9%.