Memory-efficient Low-latency Remote Photoplethysmography through Temporal-Spatial State Space Duality
Kegang Wang, Jiankai Tang, Yuxuan Fan, Jiatong Ji, Yuanchun Shi, Yuntao Wang
TL;DR
Remote photoplethysmography (rPPG) faces memory and latency bottlenecks when leveraging deep learning. The authors present ME-rPPG, a memory-efficient framework based on temporal-spatial state space duality (TSD) that enables training on long video sequences while delivering real-time, single-frame inference with minimal memory. Key contributions include a Temporal Normalization Module and a State Space Duality backbone that together achieve strong cross-dataset generalization and real-world performance, with reported memory usage of 3.6 MB and latencies around 9.46 ms, and a public code release. This work advances practical, edge-friendly rPPG for continuous non-contact cardiovascular monitoring.
Abstract
Remote photoplethysmography (rPPG), enabling non-contact physiological monitoring through facial light reflection analysis, faces critical computational bottlenecks as deep learning introduces performance gains at the cost of prohibitive resource demands. This paper proposes ME-rPPG, a memory-efficient algorithm built on temporal-spatial state space duality, which resolves the trilemma of model scalability, cross-dataset generalization, and real-time constraints. Leveraging a transferable state space, ME-rPPG efficiently captures subtle periodic variations across facial frames while maintaining minimal computational overhead, enabling training on extended video sequences and supporting low-latency inference. Achieving cross-dataset MAEs of 5.38 (MMPD), 0.70 (VitalVideo), and 0.25 (PURE), ME-rPPG outperforms all baselines with improvements ranging from 21.3% to 60.2%. Our solution enables real-time inference with only 3.6 MB memory usage and 9.46 ms latency -- surpassing existing methods by 19.5%-49.7% accuracy and 43.2% user satisfaction gains in real-world deployments. The code and demos are released for reproducibility on https://health-hci-group.github.io/ME-rPPG-demo/.
