Cascaded Vehicle Matching and Short-Term Spatial-Temporal Network for Smoky Vehicle Detection

Vehicle exhaust is the main source of air pollution with the rapid increase of fuel vehicles. Automatic smoky vehicle detection in videos is a superior solution to traditional expensive remote sensing with ultraviolet-infrared light devices for environmental protection agencies. However, it is challenging to distinguish vehicle smoke from shadow and wet regions in cluttered roads, and could be worse due to limited annotated data. In this paper, we first introduce a real-world large-scale smoky vehicle dataset with 75,000 annotated smoky vehicle images, facilitating the effective training of advanced deep learning models. To enable a fair algorithm comparison, we also built a smoky vehicle video dataset including 163 long videos with segment-level annotations. Second, we present a novel efficient cascaded framework for smoky vehicle detection which largely integrates prior knowledge and advanced deep networks. Specifically, it starts from an improved frame-based smoke detector with a high recall rate, and then applies a vehicle matching strategy to fast eliminate non-vehicle smoke proposals, and finally refines the detection with an elaborately-designed short-term spatial-temporal network in consecutive frames. Extensive experiments in four metrics demonstrated that our framework is significantly superior to hand-crafted feature based methods and recent advanced methods.