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Quaternion-based CNN for heart rate prediction from PPG
Junghwan Lee1, Youngshin Kang1, Yusang Nam1
1The Department of Computer Engineering, Kwangwoon University, Seoul, 01897, Korea.
This study introduces a novel quaternion neural network for remote photoplethysmography (rPPG) to accurately estimate heart rate from facial videos. The model enhances robustness in real-world conditions for non-contact vital sign monitoring.
Area of Science:
- Biomedical Engineering
- Computer Vision
- Signal Processing
Background:
- Remote photoplethysmography (rPPG) extracts physiological data, like heart rate, from facial videos.
- Existing rPPG methods struggle with real-world conditions like varied illumination and motion artifacts.
- Accurate, non-invasive heart rate monitoring is crucial for healthcare applications.
Purpose of the Study:
- To develop a robust rPPG model for accurate heart rate estimation from facial images.
- To overcome limitations of current signal processing and deep learning rPPG algorithms.
- To enhance the reliability of remote vital sign monitoring systems.
Main Methods:
- Proposed a novel quaternion-valued convolutional neural network (QCNN) for rPPG signal estimation.
- Explored various color formats (RGB, YUV, HSL) to enrich input data within the quaternion domain.
- Conducted experiments under diverse illumination and simulated motion artifact conditions.
Main Results:
- The QCNN model demonstrated consistently high accuracy in heart rate estimation across various environments.
- The approach proved robust against challenging conditions, including diverse lighting and motion artifacts.
- The model effectively utilizes spatial-color information for improved rPPG signal extraction.
Conclusions:
- The proposed QCNN model offers a reliable and efficient method for remote, non-contact heart rate monitoring.
- This advancement supports the development of advanced telemedicine and eHealth systems.
- Enables continuous and non-invasive vital sign monitoring crucial for future healthcare.
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