Vehicle detection in road networks having unstructured traffic using limited computational resources

Abstract

Inefficient traffic signal control system is one of the most important causes of traffic congestion in the cities of developing countries such as Bangladesh, India, Kenya, etc. This can be mitigated by adopting a decentralized traffic-responsive signal system, where vehicle detection is performed on the road through different image-based deep learning architectures amenable to limited-resource embedded platforms as available in developing countries. Deep learning architectures currently available in this regard demand high computational resources to achieve higher inference speed and better accuracy. Besides, the few existing limited-resource deep learning architectural alternatives neither attain higher inference speed nor substantial accuracy due to not overcoming the inherent limitations. To this extent, in this study, we propose a novel limited-resource deep learning architecture, namely DhakaNet, for real-time vehicle detection in on-road (street-view) traffic images. Our proposed architecture leverages enhancing Cross-Stage Partial Network and Path Aggregation Network to build the backbone and head networks, respectively. Besides, we develop a novel multi-scale attention module to extract multi-scale meaningful features from the images, where the developed multi-scale attention module boosts the detection accuracy at the cost of small overhead. Rigorous experimental evaluation of our proposed DhakaNet over three benchmark street- view traffic datasets such as DhakaAI, IITM-HeTra-A, and IITM-HeTra-B shows up to 51% faster inference speed at similar accuracy, or up to 13% higher accuracy at a similar inference speed compared to other state-of-the-art limited-resource deep learning architectural alternatives.

In addition to street-view traffic images, nowadays aerial-view traffic images are used for various traffic applications such as traffic monitoring. As aerial- view traffic images exhibit different characteristics from street-view traffic images, we develop another novel low-resource deep learning architecture, namely DhakaNet-drone, through modifying the DhakaNet architecture and adopting dilated convolution. Rigorous experimental evaluation of our proposed DhakaNet-drone over a benchmark aerial-view traffic dataset such as VisDrone shows 50% faster inference speed at similar accuracy, or 17% higher accuracy at a similar inference speed compared to the state-of-the-art alternatives. After that, we show a real implementation of our proposed approach using a client-server application. Here, a Raspberry Pi acting as a client performs vehicle detection tasks and uploads the results to a web server. This implementation demonstrates the applicability of our proposed approach in real cases. Finally, we analyze the prospect of real deployment of an automated traffic control system in the context of developing countries. Here, xi

we survey the drivers of both motorized and non-motorized vehicles in Dhaka city. The survey respondents show a positive attitude towards an automated traffic control system.