Non-Contact Respiratory Monitoring Using an RGB Camera for Real-World Applications

Sensors

Sergio Silvestri¹  Emiliano Schena¹  Chiara Romano¹  Carlo Massaroni¹ 

[1] Unit of Measurements and Biomedical Instrumentation, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo, 00128 Rome, Italy;

关键词: breathing;    contactless monitoring systems;    respiratory monitoring;    RGB cameras;   

DOI  :  10.3390/s21155126

来源: DOAJ

【 摘 要 】

Respiratory monitoring is receiving growing interest in different fields of use, ranging from healthcare to occupational settings. Only recently, non-contact measuring systems have been developed to measure the respiratory rate ($f_R$) over time, even in unconstrained environments. Promising methods rely on the analysis of video-frames features recorded from cameras. In this work, a low-cost and unobtrusive measuring system for respiratory pattern monitoring based on the analysis of RGB images recorded from a consumer-grade camera is proposed. The system allows (i) the automatized tracking of the chest movements caused by breathing, (ii) the extraction of the breathing signal from images with methods based on optical flow (FO) and RGB analysis, (iii) the elimination of breathing-unrelated events from the signal, (iv) the identification of possible apneas and, (v) the calculation of $f_R$ value every second. Unlike most of the work in the literature, the performances of the system have been tested in an unstructured environment considering user-camera distance and user posture as influencing factors. A total of 24 healthy volunteers were enrolled for the validation tests. Better performances were obtained when the users were in sitting position. FO method outperforms in all conditions. In the $f_R$ range 6 to 60 breaths/min (bpm), the FO allows measuring $f_R$ values with bias of −0.03 ± 1.38 bpm and −0.02 ± 1.92 bpm when compared to a reference wearable system with the user at 2 and 0.5 m from the camera, respectively.

【 授权许可】

Unknown