To identify dense and small-size pedestrians in surveillance systems, high-resolution cameras are widely deployed, where high-resolution images are captured and delivered to off-the-shelf pedestrian detection models. However, given the highly computation-intensive workload brought by the high resolution, the resource-constrained cameras fail to afford accurate inference in real time. To address that, we propose Hode, an offloaded video analytic framework that utilizes multiple edge nodes in proximity to expedite pedestrian detection with high-resolution inputs. Specifically, Hode can intelligently split high-resolution images into respective regions and then offload them to distributed edge nodes to perform pedestrian detection in parallel. A spatio-temporal flow filtering method is designed to enable context-aware region partitioning, as well as a DRL-based scheduling algorithm to allow accuracy-aware load balance among heterogeneous edge nodes. Extensive evaluation results using realistic prototypes show that Hode can achieve up to 2.01% speedup with very mild accuracy loss.
翻译:为了在监测系统中识别密度大、规模小的行人,广泛安装高分辨率相机,在高分辨率图像被捕获并交付给现成行人探测模型的地方广泛安装高分辨率图像。然而,鉴于高分辨率带来的高计算密集工作量,受资源限制的相机无法实时提供准确的推算。为此,我们提议Hode,一个卸载的视频分析框架,利用邻近多个边缘节点,用高分辨率投入加速行人探测。具体地说,Hode可以明智地将高分辨率图像分割到各个区域,然后将其卸载到分布的边缘节点,以平行进行行人探测。设计了一个时空流动过滤方法,以便能够进行符合环境特征的区域分区分隔,以及基于DRL的排程算法,以便在各不同边缘节点之间实现精确度负载平衡。使用现实的原型进行的广泛评价结果表明,Hode可以达到2.01%的加速速度,并造成非常轻微的精确损失。