Online Cardiac Monitoring (OCM) emerges as a compelling enhancement for the next-generation video streaming platforms. It enables various applications including remote health, online affective computing, and deepfake detection. Yet the physiological information encapsulated in the video streams has been long neglected. In this paper, we present the design and implementation of CardioLive, the first online cardiac monitoring system in video streaming platforms. We leverage the naturally co-existed video and audio streams and devise CardioNet, the first audio-visual network to learn the cardiac series. It incorporates multiple unique designs to extract temporal and spectral features, ensuring robust performance under realistic video streaming conditions. To enable the Service-On-Demand online cardiac monitoring, we implement CardioLive as a plug-and-play middleware service and develop systematic solutions to practical issues including changing FPS and unsynchronized streams. Extensive experiments have been done to demonstrate the effectiveness of our system. We achieve a Mean Square Error (MAE) of 1.79 BPM error, outperforming the video-only and audio-only solutions by 69.2% and 81.2%, respectively. Our CardioLive service achieves average throughputs of 115.97 and 98.16 FPS when implemented in Zoom and YouTube. We believe our work opens up new applications for video stream systems. We will release the code soon.
翻译:在线心脏监测(OCM)作为下一代视频流媒体平台的一项引人注目的增强功能应运而生。它支持多种应用,包括远程健康监测、在线情感计算和深度伪造检测。然而,视频流中蕴含的生理信息长期以来一直被忽视。本文介绍了CardioLive的设计与实现,这是首个应用于视频流媒体平台的在线心脏监测系统。我们利用视频与音频流天然共存的特点,设计了CardioNet——首个用于学习心脏序列的视听网络。该网络融合了多项独特设计,以提取时域与频域特征,确保在实际视频流条件下具有鲁棒性能。为实现按需服务的在线心脏监测,我们将CardioLive实现为即插即用的中间件服务,并针对帧率变化和流不同步等实际问题开发了系统性解决方案。通过大量实验验证了系统的有效性:我们实现了1.79 BPM的均方误差(MAE),分别比纯视频方案和纯音频方案提升69.2%和81.2%。在Zoom和YouTube平台部署时,CardioLive服务的平均吞吐量分别达到115.97 FPS和98.16 FPS。我们相信这项工作为视频流系统开辟了新的应用场景,相关代码即将开源。