FlashCap: Millisecond-Accurate Human Motion Capture via Flashing LEDs and Event-Based Vision
This addresses the need for affordable and accurate motion timing in applications like sports analysis, though it is incremental as it builds on existing human pose estimation methods with new hardware and data.
The paper tackles the problem of precise motion timing (PMT) in human motion capture, which is often overlooked due to lack of high-temporal-resolution datasets, by developing FlashCap, a system using flashing LEDs and event-based vision. It results in a 40% reduction in pose estimation errors and achieves millisecond-level timing accuracy.
Precise motion timing (PMT) is crucial for swift motion analysis. A millisecond difference may determine victory or defeat in sports competitions. Despite substantial progress in human pose estimation (HPE), PMT remains largely overlooked by the HPE community due to the limited availability of high-temporal-resolution labeled datasets. Today, PMT is achieved using high-speed RGB cameras in specialized scenarios such as the Olympic Games; however, their high costs, light sensitivity, bandwidth, and computational complexity limit their feasibility for daily use. We developed FlashCap, the first flashing LED-based MoCap system for PMT. With FlashCap, we collect a millisecond-resolution human motion dataset, FlashMotion, comprising the event, RGB, LiDAR, and IMU modalities, and demonstrate its high quality through rigorous validation. To evaluate the merits of FlashMotion, we perform two tasks: precise motion timing and high-temporal-resolution HPE. For these tasks, we propose ResPose, a simple yet effective baseline that learns residual poses based on events and RGBs. Experimental results show that ResPose reduces pose estimation errors by ~40% and achieves millisecond-level timing accuracy, enabling new research opportunities. The dataset and code will be shared with the community.