Traffic management systems capture tremendous video data and leverage advances in video processing to detect and monitor traffic incidents. The collected data are traditionally forwarded to the traffic management center (TMC) for in-depth analysis and may thus exacerbate the network paths to the TMC. To alleviate such bottlenecks, we propose to utilize edge computing by equipping edge nodes that are close to cameras with computing resources (e.g. cloudlets). A cloudlet, with limited computing resources as compared to TMC, provides limited video processing capabilities. In this paper, we focus on two common traffic monitoring tasks, congestion detection, and speed detection, and propose a two-tier edge computing based model that takes into account of both the limited computing capability in cloudlets and the unstable network condition to the TMC. Our solution utilizes two algorithms for each task, one implemented at the edge and the other one at the TMC, which are designed with the consideration of different computing resources. While the TMC provides strong computation power, the video quality it receives depends on the underlying network conditions. On the other hand, the edge processes very high-quality video but with limited computing resources. Our model captures this trade-off. We evaluate the performance of the proposed two-tier model as well as the traffic monitoring algorithms via test-bed experiments under different weather as well as network conditions and show that our proposed hybrid edge-cloud solution outperforms both the cloud-only and edge-only solutions.
翻译:为了缓解这些瓶颈问题,我们建议利用边缘计算方法,装备靠近相机的边缘节点,配备计算机资源(如云盘); 云层与TMC相比计算资源有限,提供有限的视频处理能力; 在本文中,我们侧重于两项共同的交通监测任务,即交通堵塞探测和速度探测,并向TMC提出一个基于双层边缘的计算模型,既考虑到云层计算能力有限,又考虑到不稳定的网络条件。我们的解决办法对每项任务都采用两种算法,一种是在边缘实施的,另一种是在TMC,这是根据不同的计算资源设计的。TMC提供强大的计算能力,而视频质量则取决于基本的网络条件。在另一方面,边缘的视频程序非常高质量,但计算资源有限。我们的模式通过两种模式,通过不同的网络测试模式,通过不同的气象模式,评估了我们的拟议轨道边缘和模式的运行模式,作为不同的气象模式,展示了我们不同的气候模式的运行模式,同时展示了我们所拟议的云层和模式的运行模式,作为不同的气候模式,同时展示了我们不同的网络的测试模式。