Moosaei, M., Zhang, Y., Micks, A., Smith, S. et al., "Region Proposal Technique for Traffic Light Detection Supplemented by Deep Learning and Virtual Data," SAE Technical Paper 2017-01-0104, 2017, doi:10.4271/2017-01-0104.
In this work, we outline a process for traffic light detection in the context of autonomous vehicles and driver assistance technology features. For our approach, we leverage the automatic annotations from virtually generated data of road scenes. Using the automatically generated bounding boxes around the illuminated traffic lights themselves, we trained an 8-layer deep neural network, without pre-training, for classification of traffic light signals (green, amber, red). After training on virtual data, we tested the network on real world data collected from a forward facing camera on a vehicle. Our new region proposal technique uses color space conversion and contour extraction to identify candidate regions to feed to the deep neural network classifier. Depending on time of day, we convert our RGB images in order to more accurately extract the appropriate regions of interest and filter them based on color, shape and size. These candidate regions are fed to a deep neural network. In this paper, we focus on a region of interest (ROI) proposal method, which works to minimize false negative and false positive candidate regions that are then fed to the deep neural network for classification. This camera-only solution has applications for many levels of autonomy, from driver assistance technology (SAE Level 2) to fully automated vehicles (SAE Level 4).