ECG-guided individual identification via PPG
This work addresses the need for more secure and reliable biometric identification using cardiovascular signals, but it is incremental as it builds on existing modalities with a novel distillation approach.
The paper tackled the problem of low information density in PPG-based individual identification by introducing ECG signals to enhance input information, resulting in a framework that improved overall accuracy by 2.8% and 3.0% on seen and unseen individual recognitions.
Photoplethsmography (PPG)-based individual identification aiming at recognizing humans via intrinsic cardiovascular activities has raised extensive attention due to its high security and resistance to mimicry. However, this kind of technology witnesses unpromising results due to the limitation of low information density. To this end, electrocardiogram (ECG) signals have been introduced as a novel modality to enhance the density of input information. Specifically, a novel cross-modal knowledge distillation framework is implemented to propagate discriminate knowledge from ECG modality to PPG modality without incurring additional computational demands at the inference phase. Furthermore, to ensure efficient knowledge propagation, Contrastive Language-Image Pre-training (CLIP)-based knowledge alignment and cross-knowledge assessment modules are proposed respectively. Comprehensive experiments are conducted and results show our framework outperforms the baseline model with the improvement of 2.8% and 3.0% in terms of overall accuracy on seen- and unseen individual recognitions.