Ji Mingcheng, Wang Ziling, Yan Rui, Liu Qingjie, Xu Shu, Tang Huajin
College of Computer Science and Technology, Zhejiang University, Hangzhou, China.
College of Computer Science, Zhejiang University of Technology, Hangzhou, China.
Front Neurosci. 2023 Feb 16;17:1123698. doi: 10.3389/fnins.2023.1123698. eCollection 2023.
Event cameras are asynchronous and neuromorphically inspired visual sensors, which have shown great potential in object tracking because they can easily detect moving objects. Since event cameras output discrete events, they are inherently suitable to coordinate with Spiking Neural Network (SNN), which has a unique event-driven computation characteristic and energy-efficient computing. In this paper, we tackle the problem of event-based object tracking by a novel architecture with a discriminatively trained SNN, called the Spiking Convolutional Tracking Network (SCTN). Taking a segment of events as input, SCTN not only better exploits implicit associations among events rather than event-wise processing, but also fully utilizes precise temporal information and maintains the sparse representation in segments instead of frames. To make SCTN more suitable for object tracking, we propose a new loss function that introduces an exponential Intersection over Union (IoU) in the voltage domain. To the best of our knowledge, this is the first tracking network directly trained with SNN. Besides, we present a new event-based tracking dataset, dubbed DVSOT21. In contrast to other competing trackers, experimental results on DVSOT21 demonstrate that our method achieves competitive performance with very low energy consumption compared to ANN based trackers with very low energy consumption compared to ANN based trackers. With lower energy consumption, tracking on neuromorphic hardware will reveal its advantage.
事件相机是一种异步且受神经形态启发的视觉传感器,因其能够轻松检测运动物体,在目标跟踪方面展现出了巨大潜力。由于事件相机输出离散事件,它们本质上适合与脉冲神经网络(SNN)协同工作,SNN具有独特的事件驱动计算特性和高能效计算能力。在本文中,我们通过一种新颖的架构——带有经过判别式训练的SNN的脉冲卷积跟踪网络(SCTN),来解决基于事件的目标跟踪问题。以一段事件作为输入,SCTN不仅能更好地利用事件之间的隐含关联而非逐事件处理,还能充分利用精确的时间信息,并在片段而非帧中保持稀疏表示。为了使SCTN更适合目标跟踪,我们提出了一种新的损失函数,该函数在电压域引入了指数交并比(IoU)。据我们所知,这是首个直接用SNN训练的跟踪网络。此外,我们还提出了一个新的基于事件的跟踪数据集,称为DVSOT21。与其他竞争跟踪器相比,在DVSOT21上的实验结果表明,与基于人工神经网络(ANN)的跟踪器相比,我们的方法在能耗极低的情况下实现了有竞争力的性能。能耗更低,在神经形态硬件上进行跟踪将显示出其优势。