Measurement of heart rate variability using off-the-shelf smart phones

Ren-You Huang, Lan-Rong Dung, Ren-You Huang, Lan-Rong Dung

Abstract

Background: The cardiac parameters, such as heart rate (HR) and heart rate variability (HRV), are very important physiological data for daily healthcare. Recently, the camera-based photoplethysmography techniques have been proposed for HR measurement. These techniques allow us to estimate the HR contactlessly with low-cost camera. However, the previous works showed limit success for estimating HRV because the R-R intervals, the primary data for HRV calculation, are sensitive to noise and artifacts.

Methods: This paper proposed a non-contact method to extract the blood volume pulse signal using a chrominance-based method followed by a proposed CWT-based denoising technique. The R-R intervals can then be obtained by finding the peaks in the denoised signal. In this paper, we taped 12 video clips using the frontal camera of a smart phone with different scenarios to make comparisons among our method and the other alternatives using the absolute errors between the estimated HRV metrics and the ones obtained by an ECG-accurate chest band.

Results: As shown in experiments, our algorithm can greatly reduce absolute errors of HRV metrics comparing with the related works using RGB color signals. The mean of absolute errors of HRV metrics from our method is only 3.53 ms for the static-subject video clips.

Conclusions: The proposed camera-based method is able to produce reliable HRV metrics which are close to the ones measured by contact devices under different conditions. Thus, our method can be used for remote health monitoring in a convenient and comfortable way.

Figures

Fig. 1
Fig. 1
The processing flow of the proposed algorithm
Fig. 2
Fig. 2
Examples for using CWT to detrend and denoise. a The original C-rPPG signal. b The CWT coefficients of the original signal. Note that the black solid line denotes the representative frequency (scales) of pulse signal computed by (13). c The zoomed-in part of original signal. d The zoomed-in part of signal denoised by CWT-BP. e The zoomed-in part of signal denoised by CWT-MAX
Fig. 3
Fig. 3
R–R intervals of the example in Fig. 2. The red dot line is the R–R intervals measured by an ECG-accurate chest band. The blue dot line is the R–R intervals computed by our method
Fig. 4
Fig. 4
The illumination changes of the face in the “motion_O3” clip
Fig. 5
Fig. 5
The face positions and illumination in “motion_F1” clip. a The face position (x-axis). b The face position (y-axis). c The illumination (grayscale) of the face

References

    1. Task Force of the European Society of Cardiology Heart rate variability standards of measurement, physiological interpretation, and clinical use. Eur Heart J. 1996;17:354–381. doi: 10.1093/oxfordjournals.eurheartj.a014868.
    1. Hertzman AB. Photoelectric plethysmography of the fingers and toes in man. Expl Biol Med. 1937;37(3):529–534. doi: 10.3181/00379727-37-9630.
    1. Peng R-C, Zhou X-L, Lin W-H, Zhang Y-T. Extraction of heart rate variability from smartphone photoplethysmograms. Comput Math Methods Med. 2015;2015:516826. doi: 10.1155/2015/516826.
    1. Huelsbusch M, Blazek V. Medical Imaging 2002. Washington: International Society for Optics and Photonics; 2002. Contactless mapping of rhythmical phenomena in tissue perfusion using ppgi; pp. 110–117.
    1. Takano C, Ohta Y. Heart rate measurement based on a time-lapse image. Med Eng Phys. 2007;29(8):853–857. doi: 10.1016/j.medengphy.2006.09.006.
    1. Verkruysse W, Svaasand LO, Nelson JS. Remote plethysmographic imaging using ambient light. Opt Express. 2008;16(26):21434–21445. doi: 10.1364/OE.16.021434.
    1. Poh M-Z, McDuff DJ, Picard RW. Non-contact, automated cardiac pulse measurements using video imaging and blind source separation. Opt Express. 2010;18(10):10762–10774. doi: 10.1364/OE.18.010762.
    1. Poh M-Z, McDuff DJ, Picard RW. Advancements in noncontact, multiparameter physiological measurements using a webcam. IEEE Trans Biomed Eng. 2011;58(1):7–11. doi: 10.1109/TBME.2010.2086456.
    1. Lewandowska M, Rumiński J, Kocejko T, et al. Measuring pulse rate with a webcam-a non-contact method for evaluating cardiac activity. In: Computer science and information systems (FedCSIS), 2011 Federated Conference On. IEEE; 2011. p. 405–10.
    1. de Haan G, Jeanne V. Robust pulse rate from chrominance-based rppg. IEEE Trans Biomed Eng. 2013;60(10):2878–2886. doi: 10.1109/TBME.2013.2266196.
    1. Wu H-Y, Rubinstein M, Shih E, Guttag JV, Durand F, Freeman WT. Eulerian video magnification for revealing subtle changes in the world. ACM Trans Graph. 2012;31(4):65. doi: 10.1145/2185520.2185561.
    1. Wang W, Stuijk S, de Haan G. Exploiting spatial redundancy of image sensor for motion robust rppg. IEEE Trans Biomed Eng. 2015;62(2):415–425. doi: 10.1109/TBME.2014.2356291.
    1. Comon P. Independent component analysis, a new concept? Signal Process. 1994;36(3):287–314. doi: 10.1016/0165-1684(94)90029-9.
    1. Cardoso J-F. High-order contrasts for independent component analysis. Neural Comput. 1999;11(1):157–192. doi: 10.1162/089976699300016863.
    1. Crowe JA, Damianou D. The wavelength dependence of the photoplethysmogram and its implication to pulse oximetry. In: Engineering in medicine and biology society, 1992 14th Annual International Conference of the IEEE, vol 6. IEEE; 1992. p. 2423–4.
    1. Martinez LFC, Paez G, Strojnik M. Optimal wavelength selection for noncontact reflection photoplethysmography. In: International Commission for Optics (ICO 22). Washington: International Society for Optics and Photonics; 2011. p. 801191.
    1. Tominaga S. Dichromatic reflection models for a variety of materials. Color Res Appl. 1994;19(4):277–285. doi: 10.1002/col.5080190408.
    1. Viola P, Jones MJ. Robust real-time face detection. Int J Comput Vis. 2004;57(2):137–154. doi: 10.1023/B:VISI.0000013087.49260.fb.
    1. Zhang C, Zhang Z. A survey of recent advances in face detection. Technical report : Tech. rep., Microsoft Research; 2010.
    1. Hjelmås E, Low BK. Face detection: a survey. Comput Vis Image underst. 2001;83(3):236–274. doi: 10.1006/cviu.2001.0921.
    1. Hsu R-L, Abdel-Mottaleb M, Jain AK. Face detection in color images. Pattern Anal Mach Intel IEEE Trans. 2002;24(5):696–706. doi: 10.1109/34.1000242.
    1. Vezhnevets V, Sazonov V, Andreeva A. A survey on pixel-based skin color detection techniques. In: Proc Graphicon, vol 3. Moscow: 2003. p. 85–92.
    1. Soni S, Namjoshi Y. Delineation of raw plethysmograph using wavelets for mobile based pulse oximeters. 2010. arXiv preprint .
    1. Peterek T, Prauzek M, Penhaker M. A new method for identification of the significant point in the plethysmografical record. In: Signal processing systems (ICSPS), 2010 2nd International Conference on, vol 1. IEEE; 2010. p. 1–362.
    1. Addison PS, Watson JN. A novel time-frequency-based 3d lissajous figure method and its application to the determination of oxygen saturation from the photoplethysmogram. Meas Sci Technol. 2004;15(11):15. doi: 10.1088/0957-0233/15/11/L01.
    1. Stein P, Kleiger R. MD: insights from the study of heart rate variability. Annu Rev Med. 1999;50(1):249–261. doi: 10.1146/annurev.med.50.1.249.

Source: PubMed

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