Mez: An Adaptive Messaging System for Latency-Sensitive Multi-Camera Machine Vision at the IoT Edge
Mez: An Adaptive Messaging System for Latency-Sensitive Multi-Camera Machine Vision at the IoT Edge
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DOI：
10.1109/access.2021.3055775
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发表时间：
2021-01-01
期刊：
影响因子：
3.9
通讯作者：
Tabkhi, Hamed
中科院分区：
文献类型：
--
作者：
George, Anjus;Ravindran, Arun;Tabkhi, Hamed
MEZ是一种新颖的发布-订阅消息传递系统，适用于物联网边缘的延迟敏感型多摄像头机器视觉应用。IoT Edge系统中的非授权无线通信的特点是由于间歇性的信道干扰而导致时延变化很大。为了在存在无线信道干扰的情况下实现用户指定的延迟，MEZ利用了机器视觉应用程序暂时容忍较低质量视频帧的能力，前提是总体应用程序精度不会受到太大不利影响。识别涉及修改帧大小并由此修改视频帧传输等待时间的有损图像变换技术的控制旋钮。MEZ实现了网络时延反馈控制器，通过图像转换控制旋钮动态调整视频帧质量，适应信道条件，同时满足时延和应用精度要求。此外，MEZ使用特定于应用程序域的存储层设计来提供低延迟操作。在具有行人检测机器视觉应用的IoT Edge试验台上的实验评估表明，MEZ能够容忍高达10倍的延迟变化，最坏情况下应用精度F1分数度量降低4.2%。MEZ的性能还在最先进的低延迟NatS消息传递系统上进行了实验评估。
Mez is a novel publish-subscribe messaging system for latency sensitive multi-camera machine vision applications at the IoT Edge. The unlicensed wireless communication in IoT Edge systems are characterized by large latency variations due to intermittent channel interference. To achieve user specified latency in the presence of wireless channel interference, Mez takes advantage of the ability of machine vision applications to temporarily tolerate lower quality video frames if overall application accuracy is not too adversely affected. Control knobs that involve lossy image transformation techniques that modify the frame size, and thereby the video frame transfer latency, are identified. Mez implements a network latency feedback controller that adapts to channel conditions by dynamically adjusting the video frame quality using the image transformation control knobs, so as to simultaneously satisfy latency and application accuracy requirements. Additionally, Mez uses an application domain specific design of the storage layer to provide low latency operations. Experimental evaluation on an IoT Edge testbed with a pedestrian detection machine vision application indicates that Mez is able to tolerate latency variations of up to 10x with a worst-case reduction of 4.2% of the application accuracy F1 score metric. The performance of Mez is also experimentally evaluated against state-of-the-art low latency NATS messaging system.