Robust Traffic Sign Recognition Against Camera Failures

Failures of the vehicle camera may compromise the correct acquisition of frames, that are subsequently used by autonomous driving tasks. A clear understanding of the behavior of the autonomous driving tasks under such failure conditions, together with strategies to avoid safety is jeopardized, are indeed necessary. This study analyses and improve the performance of Traffic Sign Recognition (TSR) systems for road vehicles under the possible occurrence of camera failures. Our experimental assessment relies on three public datasets, which are commonly used for benchmarking TSR systems. We artificially inject 13 different types of camera failures into the three datasets. Then, we exploit three deep neural networks (DNNs) to classify either a single frame of a traffic sign or a sequence (i.e., a sliding window) of frames. We show that sliding windows significantly improves the robustness of the classifier against altered frames. We confirm our observations through explainable AI, which allows understanding why different classifiers have different performance in case of camera failures.