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

Non-expensive methods for measuring heart rate and oxygen saturation are of great importance in the scope of the COVID-19 outbreak to follow up on the symptoms and help to control the disease.Smartphones are widely available and their cameras can be used to acquire relevant physiological data, such as Photo-plethysmography (PPG) signals. Covering a light source and the camera sensor with a finger, it is possible to acquire the camera-based photoplethysmography (cbPPG) signal. Two methods were analyzed in this work, namely using the rear smartphone camera and the flash LED, and using the front camera and device display as a light source. The latter presents more advantages overall - in particular, greater control over the emitted light and finger detection - and better results were found when compared to a reference device.Clinical relevance- This technology allows the pervasive monitoring of the PPG signal using a standard smartphone, providing a tool to evaluate the subject's heart rate and its variability, respiration, blood oxygenation, etc.

e-CoVig: A Novel mHealth System for Remote Monitoring of Symptoms in COVID-19.

In 2019, a new virus, SARS-CoV-2, responsible for the COVID-19 disease, was discovered. Asymptomatic and mildly symptomatic patients were forced to quarantine and closely monitor their symptoms and vital signs, most of the time at home. This paper describes e-CoVig, a novel mHealth application, developed as an alternative to the current monitoring paradigm, where the patients are followed up by direct phone contact. The e-CoVig provides a set of functionalities for remote reporting of symptoms, vital signs, and other clinical information to the health services taking care of these patients. The application is designed to register and transmit the heart rate, blood oxygen saturation (SpO2), body temperature, respiration, and cough. The system features a mobile application, a web/cloud platform, and a low-cost specific device to acquire the temperature and SpO2. The architecture of the system is flexible and can be configured for different operation conditions. Current commercial devices, such as oximeters and thermometers, can also be used and read using the optical character recognition (OCR) functionality of the system. The data acquired at the mobile application are sent automatically to the web/cloud application and made available in real-time to the medical staff, enabling the follow-up of several users simultaneously without the need for time consuming phone call interactions. The system was already tested for its feasibility and a preliminary deployment was performed on a nursing home showing promising results.