Camera-based Photoplethysmography (cbPPG) using smartphone rear and frontal cameras: an experimental study

Area of Science:

• Biomedical Engineering
• Mobile Health Technology
• Physiological Monitoring

Background:

• Accessible and affordable methods for monitoring vital signs like heart rate and oxygen saturation are crucial, especially during health crises like the COVID-19 pandemic.
• Smartphones, with their ubiquitous availability and integrated cameras, present a potential platform for non-invasive physiological data acquisition.

Purpose of the Study:

• To investigate the feasibility of using smartphone cameras for measuring physiological parameters.
• To compare two distinct methods of acquiring camera-based photoplethysmography (cbPPG) signals using smartphones.

Main Methods:

• Acquisition of cbPPG signals by covering the camera sensor and light source with a finger.
• Evaluation of two configurations: rear camera with flash LED, and front camera with device display as the light source.

Main Results:

• The front camera and device display method demonstrated superior control over light emission and finger detection.
• This method yielded results comparable to or better than a reference device for PPG signal measurement.

Conclusions:

• Smartphone-based cbPPG offers a cost-effective and pervasive solution for monitoring heart rate, heart rate variability, and potentially blood oxygenation.
• This technology has significant clinical relevance for remote patient monitoring and symptom tracking.