Advancements in Methods and Camera-Based Sensors for the Quantification of Respiration

Assessment of respiratory function allows early detection of potential disorders in the respiratory system and provides useful information for medical management. There is a wide range of applications for breathing assessment, from measurement systems in a clinical environment to applications involving athletes. Many studies on pulmonary function testing systems and breath monitoring have been conducted over the past few decades, and their results have the potential to broadly impact clinical practice. However, most of these works require physical contact with the patient to produce accurate and reliable measures of the respiratory function. There is still a significant shortcoming of non-contact measuring systems in their ability to fit into the clinical environment. The purpose of this paper is to provide a review of the current advances and systems in respiratory function assessment, particularly camera-based systems. A classification of the applicable research works is presented according to their techniques and recorded/quantified respiration parameters. In addition, the current solutions are discussed with regards to their direct applicability in different settings, such as clinical or home settings, highlighting their specific strengths and limitations in the different environments.

[1]  G Kim Prisk,et al.  Techniques for measurement of thoracoabdominal asynchrony , 2002, Pediatric pulmonology.

[2]  V. Parreira,et al.  Changes in breathing pattern and thoracoabdominal motion after bariatric surgery: A longitudinal study , 2012, Respiratory Physiology & Neurobiology.

[3]  Geng Wang,et al.  Applications of RGB-D data for 3D reconstruction in the indoor environment , 2016, 2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC).

[4]  W. Chu,et al.  Dynamic Magnetic Resonance Imaging in Assessing Lung Volumes, Chest Wall, and Diaphragm Motions in Adolescent Idiopathic Scoliosis Versus Normal Controls , 2006, Spine.

[5]  Lei Wang,et al.  A RR interval based automated apnea detection approach using residual network , 2019, Comput. Methods Programs Biomed..

[6]  Sarah H Annesley,et al.  Monitoring respiratory rate in adults. , 2020, British journal of nursing.

[7]  Hirooki Aoki,et al.  Basic study on non-contact respiration measurement during exercise tolerance test by using kinect sensor , 2015, 2015 IEEE/SICE International Symposium on System Integration (SII).

[8]  Nan-Soo Kim,et al.  Accessory Respiratory Muscle Activation during Chest Expansion Exercise using Elastic Bands in Children with Cerebral Palsy , 2016 .

[9]  Ming-Sui Lee,et al.  Noncontact respiratory measurement of volume change using depth camera , 2012, 2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[10]  Pedro Caruso,et al.  Thoracoabdominal asynchrony: Two methods in healthy, COPD, and interstitial lung disease patients , 2017, PloS one.

[11]  Ales Procházka,et al.  Microsoft Kinect Visual and Depth Sensors for Breathing and Heart Rate Analysis , 2016, Sensors.

[12]  D. C. Phillips,et al.  Programming Real-Time Computer Systems , 1966 .

[13]  Jian Zhao,et al.  LungBRN: A Smart Digital Stethoscope for Detecting Respiratory Disease Using bi-ResNet Deep Learning Algorithm , 2019, 2019 IEEE Biomedical Circuits and Systems Conference (BioCAS).

[14]  Urtnasan Erdenebayar,et al.  Multi-Class Classification of Sleep Apnea/Hypopnea Events Based on Long Short-Term Memory Using a Photoplethysmography Signal , 2019, Journal of Medical Systems.

[15]  João Jorge,et al.  Non-Contact Monitoring of Respiration in the Neonatal Intensive Care Unit , 2017, 2017 12th IEEE International Conference on Automatic Face & Gesture Recognition (FG 2017).

[16]  M J Tobin,et al.  Separation of factors responsible for change in breathing pattern induced by instrumentation. , 1985, Journal of applied physiology.

[17]  Andrew Hunter,et al.  Unconstrained Video Monitoring of Breathing Behavior and Application to Diagnosis of Sleep Apnea , 2014, IEEE Transactions on Biomedical Engineering.

[18]  M Jezeršek,et al.  Real-time 3D visualization of the thoraco-abdominal surface during breathing with body movement and deformation extraction , 2015, Physiological measurement.

[19]  Gianluigi Ferrari,et al.  Spatio-temporal video processing for respiratory rate estimation , 2015, 2015 IEEE International Symposium on Medical Measurements and Applications (MeMeA) Proceedings.

[20]  Manola Ricciuti,et al.  Contactless measurement of physiological parameters , 2019, 2019 IEEE 9th International Conference on Consumer Electronics (ICCE-Berlin).

[21]  Maysam Ghovanloo,et al.  A Vision-Based Respiration Monitoring System for Passive Airway Resistance Estimation , 2016, IEEE Transactions on Biomedical Engineering.

[22]  Antonis A. Argyros,et al.  Efficient model-based 3D tracking of hand articulations using Kinect , 2011, BMVC.

[23]  Reza Saatchi,et al.  Thermal image analysis of the skin surface centred on the tip of the nose for respiration monitoring , 2009 .

[24]  Kourosh Khoshelham,et al.  Accuracy analysis of kinect depth data , 2012 .

[25]  Sirinthip Roomkham,et al.  Promises and Challenges in the Use of Consumer-Grade Devices for Sleep Monitoring , 2018, IEEE Reviews in Biomedical Engineering.

[26]  Marc Garbey,et al.  Interacting with human physiology , 2007, Comput. Vis. Image Underst..

[28]  Lalat Indu Giri,et al.  Non-contact monitoring of human respiration using infrared thermography and machine learning , 2020 .

[29]  Sang-Heon Lee,et al.  Real Time Apnoea Monitoring of Children Using the Microsoft Kinect Sensor: A Pilot Study , 2017, Sensors.

[30]  Avishek Chatterjee,et al.  Real-Time Visual Respiration Rate Estimation with Dynamic Scene Adaptation , 2016, 2016 IEEE 16th International Conference on Bioinformatics and Bioengineering (BIBE).

[31]  J. Amat,et al.  VISION BASED RESPIRATORY MONITORING SYSTEM , 2022 .

[32]  Olga Boric-Lubecke,et al.  Multiple Subject Respiratory Pattern Recognition and Estimation of Direction of Arrival using Phase-Comparison Monopulse Radar , 2019, 2019 IEEE Radio and Wireless Symposium (RWS).

[33]  Deepak Ganesan,et al.  Respiratory Rate Monitoring in Clinical Environments with a Contactless Ultra-Wideband Impulse Radar-based Sensor System , 2020, HICSS.

[34]  P. Mognoni,et al.  Deformation of the chest wall during breathing efforts. , 1966, Journal of applied physiology.

[35]  Keerthi Ram,et al.  RespNet: A deep learning model for extraction of respiration from photoplethysmogram , 2019, 2019 41st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC).

[36]  H. Maruyama,et al.  Reliability and validity of measuring respiration movement using a wearable strain sensor in healthy subjects , 2017, Journal of physical therapy science.

[37]  Jun Horie,et al.  Breathing Movements of the Chest and Abdominal Wall in Healthy Subjects , 2012, Respiratory Care.

[38]  Eugene F. Greneker Radar sensing of heartbeat and respiration at a distance with security applications , 1997, Defense, Security, and Sensing.

[39]  Miguel A. García-González,et al.  Non-Contact Infrared-Depth Camera-Based Method for Respiratory Rhythm Measurement While Driving , 2019, IEEE Access.

[40]  P. Elangovan,et al.  Assessment of Microsoft Kinect technology (Kinect for Xbox and Kinect for windows) for patient monitoring during external beam radiotherapy , 2013, 2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (2013 NSS/MIC).

[41]  Wei Lu,et al.  4D-CT motion estimation using deformable image registration and 5D respiratory motion modeling. , 2008, Medical physics.

[42]  Ki H. Chon,et al.  Tidal Volume and Instantaneous Respiration Rate Estimation using a Volumetric Surrogate Signal Acquired via a Smartphone Camera , 2017, IEEE Journal of Biomedical and Health Informatics.

[43]  Kwasniewska,et al.  Improving Accuracy of Contactless Respiratory Rate Estimation by Enhancing Thermal Sequences with Deep Neural Networks , 2019, Applied Sciences.

[44]  Mia Folke,et al.  Comparative Provocation Test of Respiratory Monitoring Methods , 2002, Journal of clinical monitoring and computing.

[45]  Tzyy-Ping Jung,et al.  Toward Drowsiness Detection Using Non-hair-Bearing EEG-Based Brain-Computer Interfaces , 2018, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[46]  Susan M. Astley,et al.  Evaluation of Kinect 3D Sensor for Healthcare Imaging , 2016, Journal of medical and biological engineering.

[47]  S. Longhi,et al.  Respiratory rate detection algorithm based on RGB-D camera: theoretical background and experimental results. , 2014, Healthcare technology letters.

[48]  Andreas Kolb,et al.  Kinect range sensing: Structured-light versus Time-of-Flight Kinect , 2015, Comput. Vis. Image Underst..

[49]  Majid Mirmehdi,et al.  Remote, Depth-Based Lung Function Assessment , 2017, IEEE Transactions on Biomedical Engineering.

[50]  Dylan H. Morris,et al.  Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1 , 2020, The New England journal of medicine.

[51]  K. Shelley Photoplethysmography: Beyond the Calculation of Arterial Oxygen Saturation and Heart Rate , 2007, Anesthesia and analgesia.

[52]  S. Hapdey,et al.  Management of respiratory motion in PET/computed tomography: the state of the art , 2014, Nuclear medicine communications.

[53]  Kanchanjot Kaur Phokela,et al.  Use of Smartphone's Headset Microphone to Estimate the Rate of Respiration , 2020, 2020 International Conference on COMmunication Systems & NETworkS (COMSNETS).

[54]  R. Gonçalves,et al.  Assessment of muscle shortening and static posture in children with persistent asthma , 2007, European Journal of Pediatrics.

[55]  R. Yohe Respiratory distress in the newborn. , 1958, Journal. Iowa State Medical Society.

[56]  Martin Schätz,et al.  Sleep Apnea Detection with Polysomnography and Depth Sensors , 2020, Sensors.

[57]  Reza Saatchi,et al.  Non-invasive respiration monitoring by thermal imaging to detect sleep apnoea , 2019 .

[58]  Jia Chen,et al.  Tidal Volume Estimation Using Portable Ultrasound Imaging System , 2016, IEEE Sensors Journal.

[59]  Wenbing Zhao,et al.  A Survey of Applications and Human Motion Recognition with Microsoft Kinect , 2015, Int. J. Pattern Recognit. Artif. Intell..

[60]  Matteo Munaro,et al.  Performance evaluation of the 1st and 2nd generation Kinect for multimedia applications , 2015, 2015 IEEE International Conference on Multimedia and Expo (ICME).

[61]  Andrew W. Fitzgibbon,et al.  KinectFusion: real-time 3D reconstruction and interaction using a moving depth camera , 2011, UIST.

[62]  Nanning Zheng,et al.  A High Spatial Resolution Depth Sensing Method Based on Binocular Structured Light , 2017, Sensors.

[63]  Ryo Saegusa,et al.  Human-Care Rounds Robot with Contactless Breathing Measurement , 2019, 2019 International Conference on Robotics and Automation (ICRA).

[64]  Alexandre Krupa,et al.  Automatic Tracking of an Organ Section with an Ultrasound Probe: Compensation of Respiratory Motion , 2011, MICCAI.

[65]  Joachim Hornegger,et al.  Robust real-time 3D respiratory motion detection using time-of-flight cameras , 2008, International Journal of Computer Assisted Radiology and Surgery.

[66]  S. Saguem,et al.  Thorax and Abdomen Motion Analysis in Patients with Obstructive Diseases , 2016 .

[67]  Gregory F. Lewis,et al.  A novel method for extracting respiration rate and relative tidal volume from infrared thermography. , 2011, Psychophysiology.

[68]  Chang-Yeong Kim,et al.  Ultrasound image-based respiratory motion tracking , 2012, Medical Imaging.

[69]  Partha Pratim Das,et al.  Characterizations of Noise in Kinect Depth Images: A Review , 2014, IEEE Sensors Journal.

[70]  Gerhard Tröster,et al.  Unobtrusive physiological monitoring in an airplane seat , 2009, Personal and Ubiquitous Computing.

[71]  J. Downes,et al.  A clinical scoring system for the diagnosis of respiratory failure. Preliminary report on childhood status asthmaticus. , 1972, American journal of diseases of children.

[72]  Wei Li,et al.  An Unobtrusive and Non-Contact Method for Respiratory Measurement With Respiratory Region Detecting Algorithm Based on Depth Images , 2019, IEEE Access.

[73]  Ioannis T. Pavlidis,et al.  Analysis of Breathing Air Flow Patterns in Thermal Imaging , 2006, 2006 International Conference of the IEEE Engineering in Medicine and Biology Society.

[74]  Kenji Satou,et al.  Clustering and Classification of Breathing Activities by Depth Image from Kinect , 2019, BIOINFORMATICS.

[75]  Wassim Bouachir,et al.  A computer vision method for respiratory monitoring in intensive care environment using RGB-D cameras , 2017, 2017 Seventh International Conference on Image Processing Theory, Tools and Applications (IPTA).

[76]  Ki-Hyun Kim,et al.  A review of breath analysis for diagnosis of human health , 2012 .

[77]  B. Hök,et al.  Critical review of non-invasive respiratory monitoring in medical care , 2003, Medical and Biological Engineering and Computing.

[78]  Maysam Ghovanloo,et al.  A passive quantitative measurement of airway resistance using depth data , 2014, 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[79]  Majid Mirmehdi,et al.  Remote pulmonary function testing using a depth sensor , 2015, 2015 IEEE Biomedical Circuits and Systems Conference (BioCAS).

[80]  D. Moher,et al.  Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. , 2010, International journal of surgery.

[81]  Martin J Murphy,et al.  Issues in respiratory motion compensation during external-beam radiotherapy. , 2002, International journal of radiation oncology, biology, physics.

[82]  Anders Grunnet-Jepsen,et al.  Intel RealSense Stereoscopic Depth Cameras , 2017, CVPR 2017.

[83]  D. Visvikis,et al.  Surface imaging for real-time patient respiratory function assessment in intensive care. , 2020, Medical physics.

[84]  Cheung-Hwa Hsu,et al.  Design and clinic monitoring of a newly developed non-attached infant apnea monitor , 2005 .

[85]  Dominik Spinczyk,et al.  Methods for abdominal respiratory motion tracking , 2014, Computer aided surgery : official journal of the International Society for Computer Aided Surgery.

[86]  Mariusz Kaczmarek,et al.  Evaluating Accuracy of Respiratory Rate Estimation from Super Resolved Thermal Imagery , 2019, 2019 41st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC).

[87]  U. Koehler,et al.  [Respiratory Rate - a Neglected Vital Sign]. , 2017, Deutsche medizinische Wochenschrift.

[88]  Wassim Bouachir,et al.  Using machine learning models to predict oxygen saturation following ventilator support adjustment in critically ill children: A single center pilot study , 2018, bioRxiv.

[89]  Majid Mirmehdi,et al.  Toward Respiratory Assessment Using Depth Measurements from a Time-of-Flight Sensor , 2017, Front. Physiol..

[90]  Ramesh Jain,et al.  Respiration rate and volume measurements using wearable strain sensors , 2019, npj Digital Medicine.

[91]  Daniel G. Aliaga,et al.  Ieee Transactions on Pattern Analysis and Machine Intelligence 1 a Self-calibrating Method for Photogeometric Acquisition of 3d Objects , 2022 .

[92]  Rob Miller,et al.  Smart Homes that Monitor Breathing and Heart Rate , 2015, CHI.

[93]  Lalat Indu Giri,et al.  Human respiration monitoring using infrared thermography and artificial intelligence , 2020, Biomedical physics & engineering express.

[94]  N. Raichura,et al.  Breath-hold MRI in evaluating patients with pectus excavatum. , 2001, The British journal of radiology.

[95]  Matthias Nießner,et al.  State of the Art on 3D Reconstruction with RGB‐D Cameras , 2018, Comput. Graph. Forum.

[96]  T Schaeffter,et al.  Thoracic respiratory motion estimation from MRI using a statistical model and a 2-D image navigator , 2012, Medical Image Anal..

[97]  Claudio L. Lafortuna,et al.  A new instrument for the measurement of rib cage and abdomen circumference variation in respiration at rest and during exercise , 2004, European Journal of Applied Physiology and Occupational Physiology.

[98]  Livio Pinto,et al.  Calibration of Kinect for Xbox One and Comparison between the Two Generations of Microsoft Sensors , 2015, Sensors.

[99]  Tapio Seppänen,et al.  Accurate measurement of respiratory airflow waveforms using depth data , 2015, 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC).

[100]  Steffen Leonhardt,et al.  Noncontact Monitoring of Respiratory Rate in Newborn Infants Using Thermal Imaging , 2019, IEEE Transactions on Biomedical Engineering.

[101]  Raquel R Britto,et al.  Breathing pattern and thoracoabdominal motion in healthy individuals: influence of age and sex. , 2010, Revista brasileira de fisioterapia (Sao Carlos (Sao Paulo, Brazil)).

[102]  Miguel A. García-González,et al.  Drowsiness detection by thoracic effort signal analysis in real driving environments , 2011, 2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[103]  Negar Tavassolian,et al.  A Concurrent Dual-Beam Phased-Array Doppler Radar Using MIMO Beamforming Techniques for Short-Range Vital-Signs Monitoring , 2019, IEEE Transactions on Antennas and Propagation.

[104]  Emiliano Schena,et al.  Evaluation of thoraco-abdominal asynchrony using conductive textiles , 2020, 2020 IEEE International Instrumentation and Measurement Technology Conference (I2MTC).

[105]  A. Farag,et al.  Non-contact , Wavelet-based Measurement of Vital Signs using Thermal Imaging , 2005 .

[106]  Miguel A. García-González,et al.  Driver Drowsiness Detection Based on Respiratory Signal Analysis , 2019, IEEE Access.

[107]  Ioannis T. Pavlidis,et al.  Tracking human breath in infrared imaging , 2005, Fifth IEEE Symposium on Bioinformatics and Bioengineering (BIBE'05).

[108]  Federico Tombari,et al.  Analysis and Evaluation Between the First and the Second Generation of RGB-D Sensors , 2015, IEEE Sensors Journal.

[109]  Boreom Lee,et al.  Real-time estimation of respiratory rate from a photoplethysmogram using an adaptive lattice notch filter , 2014, Biomedical engineering online.

[110]  Rita Noumeir,et al.  Quantitative Assessment of Spontaneous Breathing in Children: Evaluation of a Depth Camera System , 2020, IEEE Transactions on Instrumentation and Measurement.

[111]  Paul Seddon,et al.  Options for assessing and measuring chest wall motion. , 2015, Paediatric respiratory reviews.

[112]  Hidetoshi Miike,et al.  Evaluation of Body Motion by Optical Flow Analysis , 1997 .

[113]  Daniel McDuff,et al.  Advancements in Noncontact, Multiparameter Physiological Measurements Using a Webcam , 2011, IEEE Transactions on Biomedical Engineering.

[114]  N O Strömberg,et al.  Thoracoabdominal asynchrony in small children with lung disease--methodological aspects and the relationship to lung mechanics. , 1998, Clinical physiology.

[115]  Yaoqin Xie,et al.  Respiratory motion tracking with a multi-camera vision system , 2013, 2013 IEEE International Conference on Medical Imaging Physics and Engineering.

[116]  David Sarrut,et al.  Multi-dimensional respiratory motion tracking from markerless optical surface imaging based on deformable mesh registration , 2012, Physics in medicine and biology.

[118]  Jie Lin,et al.  Towards Detection of Bus Driver Fatigue Based on Robust Visual Analysis of Eye State , 2017, IEEE Transactions on Intelligent Transportation Systems.

[119]  Frédo Durand,et al.  Phase-based video motion processing , 2013, ACM Trans. Graph..

[120]  Riku Jäntti,et al.  RSS Models for Respiration Rate Monitoring , 2017, IEEE Transactions on Mobile Computing.

[121]  N. Frijda,et al.  Emotions and respiratory patterns: review and critical analysis. , 1994, International journal of psychophysiology : official journal of the International Organization of Psychophysiology.

[122]  Remo Sala,et al.  A Survey on 3D Cameras: Metrological Comparison of Time-of-Flight, Structured-Light and Active Stereoscopy Technologies , 2018, SpringerBriefs in Computer Science.

[123]  Dominik Spinczyk,et al.  Stereoscopic liver surface reconstruction , 2012, Wideochirurgia i inne techniki maloinwazyjne = Videosurgery and other miniinvasive techniques.

[124]  Markus Vincze,et al.  An Empirical Evaluation of Ten Depth Cameras: Bias, Precision, Lateral Noise, Different Lighting Conditions and Materials, and Multiple Sensor Setups in Indoor Environments , 2019, IEEE Robotics & Automation Magazine.

[125]  Subrato Bharati,et al.  Disease Detection from Lung X-ray Images based on Hybrid Deep Learning , 2020, ArXiv.

[126]  Ashok Veeraraghavan,et al.  DistancePPG: Robust non-contact vital signs monitoring using a camera , 2015, Biomedical optics express.

[127]  Bo Tan,et al.  Respiration and Activity Detection Based on Passive Radio Sensing in Home Environments , 2020, IEEE Access.

[128]  Min-Hyung Choi,et al.  Real-Time Tidal Volume Estimation Using Iso-surface Reconstruction , 2016, 2016 IEEE First International Conference on Connected Health: Applications, Systems and Engineering Technologies (CHASE).

[129]  Francisco Javier Díaz Pernas,et al.  A Kinect-based system for cognitive rehabilitation exercises monitoring , 2014, Comput. Methods Programs Biomed..

[130]  R. Stiefelhagen,et al.  Breath rate monitoring during sleep using near-ir imagery and PCA , 2012, Proceedings of the 21st International Conference on Pattern Recognition (ICPR2012).

[131]  K. Nakajima,et al.  Monitoring of heart and respiratory rates by photoplethysmography using a digital filtering technique. , 1996, Medical engineering & physics.

[132]  M. Jannausch,et al.  Respiratory measurement utilizing a novel laser displacement technique: normal tidal breathing. , 2009, Biomedical instrumentation & technology.

[133]  Fatemeh Tahavori,et al.  A quantitative assessment of using the Kinect for Xbox 360 for respiratory surface motion tracking , 2012, Medical Imaging.

[134]  David A. Clifton,et al.  Breathing Rate Estimation From the Electrocardiogram and Photoplethysmogram: A Review , 2017, IEEE Reviews in Biomedical Engineering.

[135]  Andrea Aliverti,et al.  Tidal volume measurements in infants: Opto‐electronic plethysmography versus pneumotachograph , 2016, Pediatric pulmonology.

[136]  C. Newth,et al.  Assessment of thoraco-abdominal asynchrony. , 2009, Paediatric respiratory reviews.

[137]  D. Low,et al.  Quantification of the thorax-to-abdomen breathing ratio for breathing motion modeling. , 2013, Medical physics.

[138]  John Allen,et al.  Recent development of respiratory rate measurement technologies , 2019, Physiological measurement.

[139]  George Starkschall,et al.  Evaluation of internal lung motion for respiratory-gated radiotherapy using MRI: Part I--correlating internal lung motion with skin fiducial motion. , 2004, International journal of radiation oncology, biology, physics.

[140]  Tung-Wu Lu,et al.  Relationship between chest wall motion and diaphragmatic excursion in healthy adults in supine position. , 2009, Journal of the Formosan Medical Association = Taiwan yi zhi.

[141]  Hideo Kaneko,et al.  New scale to assess breathing movements of the chest and abdominal wall: preliminary reliability testing , 2015, Journal of physical therapy science.

[142]  Sergio Silvestri,et al.  Non-Contact Monitoring of Breathing Pattern and Respiratory Rate via RGB Signal Measurement , 2019, Sensors.

[143]  Yuan-Hsiang Lin,et al.  A Thermal Camera Based Continuous Body Temperature Measurement System , 2019, 2019 IEEE/CVF International Conference on Computer Vision Workshop (ICCVW).

[144]  Jon Howard,et al.  Accurate markerless respiratory tracking for gated whole body PET using the Microsoft Kinect , 2012, 2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC).

[145]  G. Cheron,et al.  Chest wall motion during tidal breathing. , 1997, Journal of applied physiology.

[146]  M Dojat,et al.  A knowledge-based system for assisted ventilation of patients in intensive care units , 1992, International journal of clinical monitoring and computing.

[147]  Hiroki Shirato,et al.  Accuracy of tumor motion compensation algorithm from a robotic respiratory tracking system: a simulation study. , 2007, Medical physics.

[148]  P. Sly,et al.  Laser monitoring of chest wall displacement. , 1997, The European respiratory journal.

[149]  T. Daengsuwan,et al.  Comparison between pediatric respiratory assessment measure (PRAM) score and wood asthma score to assess acute asthma exacerbation. , 2018, Asian Pacific journal of allergy and immunology.

[150]  Bo Li,et al.  Intelligent video surveillance for real-time detection of suicide attempts , 2018, Pattern Recognit. Lett..

[151]  R. Ricciardelli,et al.  Lives saved: Correctional officers’ experiences in the prevention of prisoner death by suicide , 2020 .

[152]  Wassim Bouachir,et al.  Automated video surveillance for preventing suicide attempts , 2016, ICDP.

[153]  Liang Li,et al.  Non-Contact Driver Respiration Rate Detection Technology Based on Suppression of Multipath Interference with Directional Antenna , 2020, Inf..

[154]  E. Carter,et al.  Evaluation of the interrupter technique for the use of assessing airway obstruction in children , 1994, Pediatric pulmonology.

[155]  Rainer Stiefelhagen,et al.  Breathing Rate Monitoring during Sleep from a Depth Camera under Real-Life Conditions , 2017, 2017 IEEE Winter Conference on Applications of Computer Vision (WACV).

[156]  Luc Soler,et al.  A structured light system to guide percutaneous punctures in interventional radiology , 2008, SPIE Photonics Europe.

[157]  Gianluigi Ferrari,et al.  Maximum-likelihood detection of neonatal clonic seizures by video image processing , 2014, 2014 8th International Symposium on Medical Information and Communication Technology (ISMICT).

[158]  T Tamura,et al.  Development of real-time image sequence analysis for evaluating posture change and respiratory rate of a subject in bed , 2001, Physiological measurement.

[159]  Guangtao Zhai,et al.  Abnormal respiratory patterns classifier may contribute to large-scale screening of people infected with COVID-19 in an accurate and unobtrusive manner , 2020, ArXiv.

[160]  Sarah Quirk,et al.  External respiratory motion analysis and statistics for patients and volunteers , 2013, Journal of applied clinical medical physics.

[161]  Rita Noumeir,et al.  Visualizing and Quantifying Thoraco-Abdominal Asynchrony in Children From Motion Point Clouds: A Pilot Study , 2019, IEEE Access.

[162]  Negar Tavassolian,et al.  Multi-Target Vital-Signs Monitoring Using a Dual-Beam Hybrid Doppler Radar , 2018, 2018 IEEE International Microwave Biomedical Conference (IMBioC).

[163]  Ying-Wen Bai,et al.  Design and implementation of an embedded monitor system for detection of a patient's breath by double Webcams in the dark , 2010, The 12th IEEE International Conference on e-Health Networking, Applications and Services.

[164]  M J Tobin,et al.  Respiratory monitoring in the intensive care unit. , 1988, The American review of respiratory disease.

[165]  Z. Yaniv,et al.  Monitoring Patient Respiration using a Single Optical Camera , 2007, 2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[166]  Frédo Durand,et al.  Eulerian video magnification for revealing subtle changes in the world , 2012, ACM Trans. Graph..

[167]  P Boesiger,et al.  4D MR imaging of respiratory organ motion and its variability , 2007, Physics in medicine and biology.

[168]  Lin Yang,et al.  Evaluating and Improving the Depth Accuracy of Kinect for Windows v2 , 2015, IEEE Sensors Journal.

[169]  Chenxi Yang,et al.  A Hybrid Radar-Camera Respiratory Monitoring System Based on an Impulse-Radio Ultrawideband Radar* , 2020, 2020 42nd Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC).

[170]  Mark T. Bolas,et al.  Unobtrusive measurement of subtle nonverbal behaviors with the Microsoft Kinect , 2012, VR.

[171]  Sergio Silvestri,et al.  Contact-Based Methods for Measuring Respiratory Rate , 2019, Sensors.

[172]  Fernando Morgado Dias,et al.  An Oximetry Based Wireless Device for Sleep Apnea Detection , 2020, Sensors.

[173]  H. Aoki,et al.  Non-contact respiration measurement using structured light 3-D sensor , 2012, 2012 Proceedings of SICE Annual Conference (SICE).

[174]  Digna M. González-Otero,et al.  Monitoring respiratory rate with capnography during cardiopulmonary resuscitation , 2014 .

[175]  Roland Siegwart,et al.  Kinect v2 for mobile robot navigation: Evaluation and modeling , 2015, 2015 International Conference on Advanced Robotics (ICAR).

[176]  Kim Fung Tsang,et al.  An Accurate ECG-Based Transportation Safety Drowsiness Detection Scheme , 2016, IEEE Transactions on Industrial Informatics.

[177]  Joachim Hornegger,et al.  Evaluation of a Time-of-Flight-based Respiratory Motion Management System , 2010, Bildverarbeitung für die Medizin.

[178]  K. Iloh,et al.  Spirometry in Asthma Care: A Review of the Trends and Challenges in Pediatric Practice , 2017, Clinical medicine insights. Pediatrics.

[179]  Yuhao Shan,et al.  Respiratory signal and human stress: non-contact detection of stress with a low-cost depth sensing camera , 2020, International Journal of Machine Learning and Cybernetics.

[180]  Lionel Tarassenko,et al.  Data fusion for improved camera-based detection of respiration in neonates , 2018, BiOS.

[181]  D. Falie,et al.  Respiratory motion visualization and the sleep apnea diagnosis with the time of flight (ToF) camera , 2008 .

[182]  Nassir Navab,et al.  Human skeleton tracking from depth data using geodesic distances and optical flow , 2012, Image Vis. Comput..

[183]  Changzhi Li,et al.  A Review on Recent Progress of Portable Short-Range Noncontact Microwave Radar Systems , 2017, IEEE Transactions on Microwave Theory and Techniques.

[184]  H. Macher,et al.  FIRST EXPERIENCES WITH KINECT V2 SENSOR FOR CLOSE RANGE 3D MODELLING , 2015 .

[185]  Cordelia Schmid,et al.  Learning realistic human actions from movies , 2008, 2008 IEEE Conference on Computer Vision and Pattern Recognition.

[186]  C. Xiangdong,et al.  Perioperative Care Provider's Considerations in Managing Patients with the COVID-19 Infections , 2020 .

[187]  Andrew W. Fitzgibbon,et al.  KinectFusion: Real-time dense surface mapping and tracking , 2011, 2011 10th IEEE International Symposium on Mixed and Augmented Reality.

[188]  A. Halbower,et al.  Non-contact tidal volume measurement through thin medium thermal imaging , 2018, Smart Health.

[189]  Michael Arens,et al.  Low-cost commodity depth sensor comparison and accuracy analysis , 2014, Security and Defence.

[190]  R. H. Shepard,et al.  High resolution display for variables in volume-displacement body plethysmography. , 1966, Journal of applied physiology.

[191]  Wassim Bouachir,et al.  Computerized Medical Imaging and Graphics 3 D imaging system for respiratory monitoring in pediatric intensive care environment , 2018 .

[192]  Parisa Rashidi,et al.  DeepSOFA: A Continuous Acuity Score for Critically Ill Patients using Clinically Interpretable Deep Learning , 2018, Scientific Reports.

[193]  Kazuhisa Takahashi,et al.  An Analysis of Chest Wall and Diaphragm Motions in Patients With Idiopathic Scoliosis Using Dynamic Breathing MRI , 2004, Spine.

[194]  I. Pavlidis,et al.  Noncontact measurement of breathing function , 2006, IEEE Engineering in Medicine and Biology Magazine.

[195]  Theodoros N. Arvanitis,et al.  Chest wall motion analysis in healthy volunteers and adults with cystic fibrosis using a novel Kinect-based motion tracking system , 2016, Medical & Biological Engineering & Computing.

[196]  Sun K Yoo,et al.  Radar-Based Detection of Respiration Rate with Adaptive Harmonic Quefrency Selection , 2020, Sensors.

[197]  Hao Li,et al.  Depth Sensor-Based Realtime Tumor Tracking for Accurate Radiation Therapy , 2014, Eurographics.

[198]  C. Poets,et al.  Determinants of lung volume in spontaneously breathing preterm infants. , 1997, American journal of respiratory and critical care medicine.

[199]  Jinho Jeong,et al.  Non-Contact Measurement of Human Respiration and Heartbeat Using W-band Doppler Radar Sensor , 2020, Sensors.

[200]  Yasue Kishino,et al.  PASNIC: a thermal based privacy-aware sensor node for image capturing , 2019, UbiComp/ISWC Adjunct.

[201]  Sander Stuijk,et al.  Robust respiration detection from remote photoplethysmography. , 2016, Biomedical optics express.

[202]  R Merget,et al.  Body plethysmography--its principles and clinical use. , 2011, Respiratory medicine.

[203]  Joachim Hornegger,et al.  Time-of-flight sensor for respiratory motion gating. , 2008, Medical physics.

[204]  Reza Saatchi,et al.  Real-time vision based respiration monitoring system , 2010, 2010 7th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP 2010).

[205]  Олег Костянтинович Боділовський Non-contact respiration monitoring using optical sensors , 2014 .

[206]  Asnida Abdul Wahab,et al.  Assessment of inspiration and expiration time using infrared thermal imaging modality , 2019, Infrared Physics & Technology.

[207]  Alberto Taboada-Crispi,et al.  Computer Vision-Based Estimation of Respiration Signals , 2019 .

[208]  Reza Saatchi,et al.  Exploratory Study to Evaluate Respiratory Rate Using a Thermal Imaging Camera , 2019, Respiration.

[209]  Lionel Tarassenko,et al.  Non-contact measurement of oxygen saturation with an RGB camera. , 2015, Biomedical optics express.

[210]  J Stocks,et al.  Measurement of lung volumes by plethysmography. , 1997, The European respiratory journal.

[211]  R K Millard,et al.  Assessing thoracoabdominal asynchrony. , 2001, Clinical physiology.

[212]  W. Cao,et al.  Breath analysis: potential for clinical diagnosis and exposure assessment. , 2006, Clinical chemistry.

[213]  Hiram Ponce,et al.  A Contactless Respiratory Rate Estimation Method Using a Hermite Magnification Technique and Convolutional Neural Networks , 2020 .

[214]  Fang-Fang Yin,et al.  Four-dimensional magnetic resonance imaging (4D-MRI) using image-based respiratory surrogate: a feasibility study. , 2011, Medical physics.

[215]  Soon-Yong Park,et al.  Real-Time External Respiratory Motion Measuring Technique Using an RGB-D Camera and Principal Component Analysis † , 2017, Sensors.

[216]  Sander Oude Elberink,et al.  Accuracy and Resolution of Kinect Depth Data for Indoor Mapping Applications , 2012, Sensors.

[217]  F. Ducharme,et al.  The Preschool Respiratory Assessment Measure (PRAM): a responsive index of acute asthma severity. , 2000, The Journal of pediatrics.

[218]  Rafael Beserra Gomes,et al.  Efficient 3D object recognition using foveated point clouds , 2013, Comput. Graph..

[219]  Joan Lasenby,et al.  SLP: A Zero-Contact Non-Invasive Method for Pulmonary Function Testing , 2010, BMVC.

[220]  Charles L. Dumoulin,et al.  Assessing the relationship between movement and airflow in the upper airway using computational fluid dynamics with motion determined from magnetic resonance imaging. , 2017, Clinical biomechanics.

[221]  Se Dong Min,et al.  Noncontact Respiration Rate Measurement System Using an Ultrasonic Proximity Sensor , 2010, IEEE Sensors Journal.

[222]  S. Blocker,et al.  The impact of respiratory gating on improving volume measurement of murine lung tumors in micro-CT imaging , 2019, bioRxiv.

[223]  Edgar A. Bernal,et al.  Non contact monitoring of respiratory function via depth sensing , 2014, IEEE-EMBS International Conference on Biomedical and Health Informatics (BHI).

[224]  Lei Dong,et al.  Modeling respiratory motion for reducing motion artifacts in 4D CT images. , 2013, Medical physics.

[225]  J. Hankinson,et al.  Standardisation of spirometry , 2005, European Respiratory Journal.

[226]  Thomas Butkiewicz Low-cost coastal mapping using Kinect v2 time-of-flight cameras , 2014, 2014 Oceans - St. John's.

[227]  A. Aliverti,et al.  Chest wall regional volumes in obese women , 2013, Respiratory Physiology & Neurobiology.

[228]  David J. Hawkes,et al.  Respiratory motion models: a review. , 2013 .

[229]  Rex Cardan Consumer-Grade Cameras and Other Approaches to Surface Imaging , 2020 .

[230]  Sander Stuijk,et al.  Exploiting Spatial Redundancy of Image Sensor for Motion Robust rPPG , 2015, IEEE Transactions on Biomedical Engineering.

[231]  S. J. Cala,et al.  Chest wall and lung volume estimation by optical reflectance motion analysis. , 1996, Journal of applied physiology.

[232]  Jodee Anderson,et al.  Newborn respiratory disorders. , 2010, Pediatrics in review.

[233]  James A. Michener Evaluation of Microsoft Kinect 360 and Microsoft Kinect One for robotics and computer vision applications , 2014 .

[234]  Ioannis Pavlidis,et al.  Thermal infrared imaging: a novel method to monitor airflow during polysomnography. , 2009, Sleep.

[235]  J. Rohrbaugh,et al.  Cardiorespiratory interactions: Noncontact assessment using laser Doppler vibrometry. , 2016, Psychophysiology.

[236]  Reza Saatchi,et al.  Facial tracking method for noncontact respiration rate monitoring , 2010, 2010 7th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP 2010).

[237]  Douglas E. Dow,et al.  Physical Thorax Model and 2D Grid of Force Sensors to Monitor Respiration , 2019 .

[238]  G. Hanna,et al.  Assessment of chest wall movement following thoracotomy: a systematic review , 2020, Journal of thoracic disease.

[239]  M. Oudkerk,et al.  Respiratory level tracking with visual biofeedback for consistent breath-hold level with potential application in image-guided interventions , 2018, European Radiology Experimental.

[240]  J. Feldman,et al.  When Does Apparatus Dead Space Matter for the Pediatric Patient?: Reprint , 2014, Anesthesia and analgesia.

[241]  G. Lenz,et al.  Capnometry for continuous postoperative monitoring of nonintubated, spontaneously breathing patients , 1991, Journal of Clinical Monitoring.

[242]  R. Saatchi,et al.  Respiration rate monitoring methods: A review , 2011, Pediatric pulmonology.

[243]  Xiaohua Zhu,et al.  Noncontact Vital Sign Detection based on Stepwise Atomic Norm Minimization , 2015, IEEE Signal Processing Letters.

[244]  Rafael Arnay,et al.  Using Kinect on an Autonomous Vehicle for Outdoors Obstacle Detection , 2016, IEEE Sensors Journal.

[245]  Hiram Ponce,et al.  Non-contact breathing rate monitoring system using a magnification technique and convolutional networks , 2020, Symposium on Medical Information Processing and Analysis.

[246]  Florian Büther,et al.  A dual-Kinect approach to determine torso surface motion for respiratory motion correction in PET. , 2015, Medical physics.

[247]  Prasant Mohapatra,et al.  Contactless Breathing Rate Monitoring in Vehicle Using UWB Radar , 2018, RealWSN@SenSys.

[248]  Fatemeh Tahavori,et al.  Marker-less respiratory motion modeling using the Microsoft Kinect for Windows , 2014, Medical Imaging.

[249]  Junyi Xia,et al.  A real-time respiratory motion monitoring system using KINECT: proof of concept. , 2012, Medical physics.

[250]  M Paiva,et al.  Measurement of thoracoabdominal asynchrony: importance of sensor sensitivity to cross section deformations. , 2000, Journal of applied physiology.

[251]  J H Auchincloss,et al.  Impedance pneumograph and magnetometer methods for monitoring tidal volume. , 1974, Journal of applied physiology.

[252]  Hans-Peter Meinzer,et al.  Influence of different breathing maneuvers on internal and external organ motion: use of fiducial markers in dynamic MRI. , 2005, International journal of radiation oncology, biology, physics.

[253]  Lee Sze Wei,et al.  Comparative Study of Intel R200, Kinect v2, and Primesense RGB-D Sensors Performance Outdoors , 2019, IEEE Sensors Journal.

[254]  D. Mant,et al.  Normal ranges of heart rate and respiratory rate in children from birth to 18 years of age: a systematic review of observational studies , 2011, The Lancet.

[255]  Daniel J. McDuff,et al.  Simple and affordable imaging of multiple physiological parameters with RGB camera-based diffuse reflectance spectroscopy. , 2020, Biomedical optics express.