REVIEW 3 major objections 5 minor 91 references
Contactless pulse rate assessment: Results and insights for application in driving simulator
T0 review · 3 major / 5 minor · reviewed 2026-08-16 · deepseek-v4-flash
Pith's one-line read A webcam-based video pipeline can estimate a driver's pulse rate in a driving simulator to within about 5 beats per minute of a wrist-worn reference sensor, the paper claims.
desk verdict Honest rPPG application paper, but the headline accuracy number is circular; the age-group finding is the more robust result. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
The load-bearing machinery is the Signal of Change in Light Intensity (SCLI), extracted as the first principal component of the mean red, green, and blue pixel values over a face-without-eyes region from every video frame, followed by a modified Pan–Tompkins algorithm for peak detection. Eulerian video magnification (EVM)—an algorithm that amplifies tiny temporal color changes in video—is applied as an optional preprocessing step. A linear correction $y = a x + b$ (with $a = 0.96$, $b = -74.01$ for the EVM case) is then applied to video-derived pulse-rate values to remove a systematic deviation that grows with pulse rate; this correction is grounded in the observation that the Empatica E4 itself shows a similar linear bias against an ECG-based reference in independent data [66].
What would settle it
Run the published pipeline unchanged—same face detector, same 433 ms moving average for the after-EVM case, same linear correction $y = 0.96x - 74.01$—on a fresh set of driving-simulator videos with simultaneous Empatica E4 recordings, and compute MAE on those held-out sequences. If the error is close to the uncorrected 10.55 bpm rather than 5.04 bpm, the correction was an in-sample artifact; if MAE stays near 5 bpm, the central accuracy claim generalizes.
Extended reading notes
Core claim
The paper's central claim is that a complete video-only pipeline—face detection, facial-skin region-of-interest extraction, optional EVM, PCA-based signal extraction, and a modified Pan–Tompkins peak detector—can turn ordinary webcam footage of a person driving a simulator into a usable pulse-rate estimate. With EVM and a linear correction fitted to their data, the pipeline's mean absolute error against the Empatica E4 wristband was 5.04 ± 0.37 bpm (RMSE 6.38 ± 0.51 bpm); without EVM the MAE was 6.48 ± 0.41 bpm. The paper also claims that the video-derived pulse rate preserves a meaningful physiological signal: it separates younger drivers (mean 80.99 bpm) from older drivers (mean 73.12 bpm) with statistical significance, as the reference sensor does. Cross-correlation between the video signal and the wrist blood-volume-pulse waveform is very low (0.08–0.09), so the claim is about heart-rate estimation at the segment level, not waveform fidelity.
Load-bearing premise
The reported 5.04 bpm error assumes that the linear correction parameters and the moving-average window width, both chosen to minimize error on the same recordings, will also reduce error on new recordings rather than merely fitting noise.
Editorial extensions
If this is right
- A single low-cost webcam can replace a wrist-worn PPG sensor for group-level pulse-rate monitoring in driving-simulator studies, such as comparing younger and older drivers.
- EVM's accuracy gain is small relative to its cost—about 20 extra seconds per 30-second sequence—so practical quasi-real-time deployments may skip EVM and still retain most of the benefit.
- The linear-bias correction transfers conceptually to other reference sensors: because the wrist sensor itself overestimates pulse rate at higher rates, some of the raw error in video-versus-reference comparisons is sensor bias rather than video error.
- Video-derived pulse rate can support age-related driver workload and stress studies, provided per-individual errors are tolerated.
Reading between the lines
- If the correction generalizes, the same calibration approach could be used to cross-calibrate webcam rPPG against any wrist-worn PPG sensor, letting laboratories pool data collected with different wearables.
- The low waveform correlation coexisting with usable beat-rate estimates suggests that segment-averaged pulse rate, not pulse waveform, is what this method reliably delivers; a testable extension is whether heart-rate variability features derived from the same signal also survive the motion-heavy setting.
- A natural next experiment is to compare the video pipeline directly against ECG (not wrist PPG) in the same simulator; the paper's use of the Faros 360 data points toward this, and it would separate correction of sensor bias from correction of video error.
- For driver monitoring, the method's practical ceiling may be set by head motion and lighting; the authors' own improvement list—standardized lighting, explicit skin segmentation, and higher-resolution cameras—gives a concrete checklist for pushing MAE below the roughly 2 bpm best cases they observed.
Signed reviews
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript presents a contactless pulse rate (PR) estimation pipeline for driving-simulator scenarios. The pipeline uses YOLO-based face detection, eye exclusion to form a facial skin ROI, optional Eulerian Video Magnification (EVM), PCA-based extraction of a light-intensity signal, and a modified Pan–Tompkins peak detector with a moving-average smoothing step. The authors compare video-derived PR against simultaneously recorded Empatica E4 reference values, report MAE/RMSE before and after a linear correction, test whether EVM improves accuracy, evaluate the method on two public datasets, and compare younger versus older drivers. The headline result is an MAE of 5.04 bpm and RMSE of 6.38 bpm after EVM and linear correction, with the claim that this demonstrates feasibility of rPPG-based PR monitoring in driving simulators. The paper also includes a time-complexity analysis of EVM and an independent assessment of Empatica E4 bias using Faros 360 data.
Significance. If the reported accuracy were out-of-sample, the study would be a useful feasibility demonstration for contactless driver monitoring in a realistic, retrospective driving-simulator corpus. The manuscript has several strengths: it uses a relatively large participant sample (79 recordings from 65 participants) with a wide PR range, makes the dataset publicly available on Zenodo, explicitly compares EVM and non-EVM processing, provides execution-time measurements, and uses an independent Empatica E4 versus Faros 360 dataset to assess reference-device bias. The age-group difference in PR is supported even before the linear correction, which is a meaningful result. However, the central quantitative accuracy claim currently rests on parameters selected on the same data used to report the errors, so the numbers should be interpreted as in-sample optima until cross-validation or an external correction is reported numerically.
major comments (3)
- [Section 2.5, Section 2.7, Figure 5] The headline accuracy numbers (MAE 5.04 ± 0.37 bpm, RMSE 6.38 ± 0.51 bpm for A.EVM after correction) are computed on the same data used to choose two sets of parameters. Section 2.5 states that the moving-average window width is selected per overlapping sequence to minimize MAE against the Empatica E4 reference and the per-sequence optima are then averaged; Section 2.7 fits the linear correction parameters a and b to the same B.EVM/A.EVM differences that are subsequently corrected and reported in Figure 5. No cross-validation, leave-one-subject-out split, or nested tuning is described. The 6.48-to-5.04 bpm improvement therefore reflects a fitted optimum on the evaluation data, not a predictive accuracy. The paper should provide out-of-sample estimates, for example participant-level cross-validation for both the window width and the linear correction, or re-label the headline numbers as in-sample and report the external-correction results as the predictive estimate.
- [Section 3, Table 2] The age-group finding is not an artifact of the correction: the pre-correction p-values (B.EVM p=0.04, A.EVM p=0.01) are already significant and the reference data show p<0.001. However, the p.f. and p.f.f. columns and the Cliff's delta values (0.29 to 0.38) are computed after applying the in-sample linear correction, so these strengthened results are entangled with fitted parameters. The paper should report effect sizes for the uncorrected data with confidence intervals and treat the post-correction values as supporting, not primary, evidence.
- [Section 2.7, Figure 5 (bottom panel)] The external correction derived from Medarević et al. [66] is the only genuinely out-of-sample correction in the paper, yet the manuscript only states that 'errors decrease' and gives no numeric MAE, RMSE, AAE, SAE, or ARE for this correction. Because the external fit parameters (a=0.32, b=-30.42) differ substantially from the in-sample fits, the resulting error values are important for judging generalization; please report them explicitly.
minor comments (5)
- [Equation (4)] The definition of ARE contains a double summation with N in both the inner and outer sums; this is malformed and should be corrected.
- [Figure 5 caption] The text refers to upper, middle, and bottom panels, but the caption mentions only upper and lower panels; align the caption with the three-panel layout.
- [Discussion, reference [1]] The Discussion refers to 'Renne et al.'; the cited author is Renner et al. Please correct the name.
- [Abstract and Table 3] The abstract states that EVM adds 'about 20 s for 30 s sequence', while Table 3 reports 23.26 ± 0.86 s for single-core execution and 16.61 ± 1.62 s for four-core execution on a 30-s video; please clarify which configuration the abstract figure refers to.
- [Table 1] The row 'Our approach applied to the second dataset presented in [61]' leaves the MAE and RMSE cells empty; either fill them in or state explicitly why they are unavailable.
Circularity Check
The headline MAE of 5.04 bpm is an in-sample optimum: both the §2.5 moving-average window width and the §2.7 linear correction are fit against the Empatica E4 reference used for scoring, with no held-out split.
-
fitted input called prediction
[Section 2.5, Extraction of Light Changes and Peak Detection]
"The search for the moving average window width is conducted with the widths that varied from 33 ms to 1 s with the step of 33 ms (corresponds to averaging from one to 30 samples because the sampling frequency is 30 Hz) [51]. Suitable values of the window width are determined for each overlapping video sequence to minimize the mean absolute error (MAE) in comparison with the reference average PR values from the Empatica E4 sensor in the corresponding sequence. All suitable values of the moving average window widths are then averaged to obtain a unique parameter applicable to all videos."
The smoothing window used in the modified Pan-Tompkins peak detector is selected per sequence by minimizing MAE against the Empatica E4 reference, then averaged into a single width. The same reference is later used to report the post-smoothing MAE/RMSE. This makes the smoothing parameter part of an in-sample fit to the evaluation target, so the reported error is not an independent measure of predictive accuracy. No cross-validation or held-out split is described, and the subsequent linear correction in §2.7 compounds the in-sample character of the reported 5.04 bpm result.
-
fitted input called prediction
[Section 2.7, Additional Processing of Extracted Pulse Rates]
"Therefore, we decide to design a linear fit (showcased on the left-hand panel graphs in Figure 2). Based on this, we correct the extracted faults by subtracting the linear fit values from the calculated differences between the reference and extracted PR (linear fit correction). ... In our case, a simple linear fit correction is applied, with parameters a and b in the basic linear equation y = a ∗ x + b, which are 0.94 and −69.41 for B.EVM as well as 0.96 and −74.01 for A.EVM, respectively, effectively reducing observed deviations."
The linear correction is estimated from the residual differences between video-derived PR and Empatica E4 PR on the same recordings whose corrected errors are then reported in Figure 5 and Table 1. Subtracting a residual fit from the data used to estimate it cannot increase the mean error on those same data, so the drop from 6.48 bpm (B.EVM) to 5.04 bpm (A.EVM) is an in-sample improvement by construction, not an out-of-sample prediction. Because the paper reports no validation split, the headline MAE/RMSE values are fitted optima rather than held-out accuracies.
full rationale
The rPPG pipeline itself is not circular: face/skin detection, PCA-based SCLI extraction, and modified Pan-Tomkins peak detection are implemented independently, and the paper additionally evaluates the pipeline on public datasets (Table 1) and uses the Medarevic et al. [66] Empatica E4 vs. Faros 360 comparison as an external anchor. The age-group difference is also present before correction (B.EVM p=0.04, A.EVM p=0.01 in Table 2), giving the group-level feasibility claim independent content. However, the headline accuracy figure is partially circular: §2.5 tunes the moving-average window width by minimizing MAE against the Empatica E4 reference on each sequence, and §2.7 fits a linear correction y = a*x + b to the residual differences between video PR and the same Empatica E4 reference, then reports the corrected errors (MAE 5.04 bpm, RMSE 6.38 bpm) on that same data. The corrected error is therefore an in-sample optimum, and the EVM-vs-no-EVM comparison (6.48 vs 5.04 bpm) is entangled with correction parameters fit separately for each condition. Score 6 rather than higher because the underlying signal-extraction chain and the age-group/group-level findings are not themselves derived from the fitted parameters, and the paper includes some genuinely external evaluations.
Assumptions & free parameters
free parameters (4)
- Moving average window width for peak detection =
400 ms B.EVM, 433 ms A.EVM
- Prominence threshold =
0.15
- EVM magnification factor =
20
- Linear fit correction parameters a and b =
B.EVM: a=0.94, b=-69.41; A.EVM: a=0.96, b=-74.01
assumptions (4)
- domain assumption Empatica E4 PR and IBI values are treated as ground truth for evaluation.
- domain assumption The first principal component of the mean R, G, B pixel values reflects cardiac blood-volume changes.
- domain assumption EVM without phase-based motion processing is applicable to the recorded head movements.
- ad hoc to paper The device-difference error follows a stable linear trend that can be corrected by a global linear fit.
Cite this review
Pith. "Pith review of Contactless pulse rate assessment: Results and insights for application in driving simulator." pith.science (2026). https://pith.science/paper/CUXA5AMT
@misc{pith2026250501299,
author = {Pith},
title = {Pith review of: Contactless pulse rate assessment: Results and insights for application in driving simulator},
year = {2026},
howpublished = {\url{https://pith.science/paper/CUXA5AMT}},
note = {Machine review of arXiv:2505.01299}
}
read the original abstract
Remote photoplethysmography (rPPG) offers a promising solution for non-contact driver monitoring by detecting subtle blood flow-induced facial color changes from video. However, motion artifacts in dynamic driving environments remain key challenges. This study presents an rPPG framework that combines signal processing techniques before and after applying Eulerian Video Magnification (EVM) for pulse rate (PR) estimation in driving simulators. While not novel, the approach offers insights into the efficiency of the EVM method and its time complexity. We compare results of the proposed rPPG approach against reference Empatica E4 data and also compare it with existing achievements from the literature. Additionally, the possible bias of the Empatica E4 is further assessed using an independent dataset with both the Empatica E4 and the Faros 360 measurements. EVM slightly improves PR estimation, reducing the mean absolute error (MAE) from 6.48 bpm to 5.04 bpm (the lowest MAE (~2 bpm) was achieved under strict conditions) with an additional time required for EVM of about 20 s for 30 s sequence. Furthermore, statistically significant differences are identified between younger and older drivers in both reference and rPPG data. Our findings demonstrate the feasibility of using rPPG-based PR monitoring, encouraging further research in driving simulations.
Reference graph
Works this paper leans on
-
[66]
Distress Detection in VR environment using Empatica E4 wristband and Bittium Faros 360
Medarević, J.; Miljković, N.; Stojmenova Pečečnik, K.; Sodnik, J. Distress Detection in VR environment using Empatica E4 wristband and Bittium Faros 360. Front. Physiol. 2025, 16, 1480018. https://doi.org/10.3389/fphys.2025.1480018
-
[1]
Renner, P.; Gleichauf, J.; Winkelmann, S. Non -Contact In -Car Monitoring of Heart Rate: Evaluating the Eulerian Video Magnification Algorithm in a Driving Simulator Study. In Proceedings of the Mensch und Computer 2024, Karlsruhe, Germany, 1 –4 September 2024; pp. 651–654. https://doi.org/10.1145/3670653.3677493. 21
arXiv 2024
-
[2]
An EO/IR monitoring system for noncontact physiological signal analysis in automated vehicles
Nijskens, L.; van der Hurk, S.E.; van den Broek, S.P.; Louvenberg, S.; Souman, J.L.; Bos, J.E.; ter Haar, F.B. An EO/IR monitoring system for noncontact physiological signal analysis in automated vehicles. In Proceedings of the SPIE Autonomous Systems for Security and Defence, Edinburgh, UK, 13 November 2024; Volume 13207, pp. 55–68. https://doi.org/10.11...
-
[3]
Gaur, P.; Temple, D.S.; Hegarty-Craver, M.; Boyce, M.D.; Holt, J.R.; Wenger, M.F.; Preble, E.A.; Eckhoff, R.P.; McCombs, M.S.; Davis -Wilson, H.C.; et al. Continuous Monitoring of Heart Rate Variability in Free-Living Conditions Using Wearable Sensors: Exploratory Observational Study. JMIR Form. Res. 2024, 8, e53977. https://doi.org/10.2196/53977
doi:10.2196/53977 2024
-
[4]
Simulation -based driver scoring and profiling system
Medarević, J.; Tomažič, S.; Sodnik, J. Simulation -based driver scoring and profiling system. Heliyon 2024, 10, e40310. https://doi.org/10.1016/j.heliyon.2024.e40310
-
[5]
Leveraging wearable sensors in virtual reality driving simulators: A review of techniques and applications
Boboc, R.G.; Butilă, E.V.; Butnariu, S. Leveraging wearable sensors in virtual reality driving simulators: A review of techniques and applications. Sensors 2024, 24, 4417
2024
-
[6]
Photoplethysmography revisited: From contact to noncontact, from point to imaging
Sun, Y.; Thakor, N. Photoplethysmography revisited: From contact to noncontact, from point to imaging. IEEE Trans. Biomed. Eng. 2015, 63, 463 –477. https://doi.org/10.1109/TBME.2015.2476337
arXiv 2015
-
[7]
Dudarev, V.; Barral, O.; Zhang, C.; Davis, G.; Enns, J.T. On the reliability of wearable technology: A tutorial on measuring heart rate and heart rate variability in the wild. Sensors 2023, 23, 5863. https://doi.org/10.3390/s23135863
Show all 91 references
-
[8]
Wearable technologies for electrodermal and cardiac activity measurements: A comparison between fitbit sense, empatica E4 and shimme r GSR3+
Ronca, V.; Martinez -Levy, A.C.; Vozzi, A.; Giorgi, A.; Aricò, P.; Capotorto, R.; Borghini, G.; Babiloni, F.; Di Flumeri, G. Wearable technologies for electrodermal and cardiac activity measurements: A comparison between fitbit sense, empatica E4 and shimme r GSR3+. Sensors 20...
2023 doi
-
[9]
Measuring pulse rate with a webcam
Lewandowska, M.; Nowak, J. Measuring pulse rate with a webcam. J. Med. Imaging Health Inform. 2012, 2, 87–92. https://doi.org/10.1166/jmihi.2012.1064
2012
-
[10]
Validation of heart rate extraction using video imaging on a built-in camera system of a smartphone
Kwon, S.; Kim, H.; Park, K.S. Validation of heart rate extraction using video imaging on a built-in camera system of a smartphone. In Proceedings of the 2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, San Diego, CA, USA, 28 August–...
2012
-
[11]
Non-contact, automated cardiac pulse measurements using video imaging and blind source separation
Poh, M.Z.; McDuff, D.J.; Picard, R.W. Non-contact, automated cardiac pulse measurements using video imaging and blind source separation. Opt. Express 2010, 18, 10762 –10774. https://doi.org/10.1364/OE.18.010762
2010 doi
-
[12]
Optimal color channel combination across skin tones for remote heart rate measurement in camera -based photoplethysmography
Ernst, H.; Scherpf, M.; Malberg, H.; Schmidt, M. Optimal color channel combination across skin tones for remote heart rate measurement in camera -based photoplethysmography. Biomed. Signal Process. Control 2021, 68, 102644. https://doi.org/10.1016/j.bspc.2021.102644
2021
-
[13]
Eulerian video magnification for revealing subtle changes in the world
Wu, H.Y.; Rubinstein, M.; Shih, E.; Guttag, J.; Durand, F.; Freeman, W. Eulerian video magnification for revealing subtle changes in the world. ACM Trans. Graph. (TOG) 2012, 31, 1–8. https://doi.org/10.1145/2185520.2185561
2012
-
[14]
Pulse rate assessment: Eulerian video magnification vs
Miljković, N.; Trifunović, D. Pulse rate assessment: Eulerian video magnification vs. electrocardiography recordings. In Proceedings of the 12th Symposium on Neural Network Applications in Electrical Engineering (NEUREL), Belgrade, Serbia, 25 –27 November 2014; IEEE: Piscatawa...
2014
-
[15]
Phase -based video motion processing
Wadhwa, N.; Rubinstein, M.; Durand, F.; Freeman, W.T. Phase -based video motion processing. ACM Trans. Graph. (ToG) 2013, 32, 1–10. https://doi.org/10.1145/2461912.2461966
2013
-
[16]
Detecting pulse from head motions in video
Balakrishnan, G.; Durand, F.; Guttag, J. Detecting pulse from head motions in video. In Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, Portland, OR, USA, 23–28 June 2013; pp. 3430–3437. https://doi.org/10.1109/CVPR.2013.440
2013 doi
-
[17]
Detecting pulse from head motions using smartphone camera
Lomaliza, J.P.; Park, H. Detecting pulse from head motions using smartphone camera. In Proceedings of the International Conference on Advanced Engineering Theory and Applications, Busan, Vietnam, 8 –10 December 2016; Springer International Publishing: Cham, Switzerland, 2016; ...
2016 doi
-
[18]
Quantifying Drivers’ Physiological Responses to Take-Over Requests in Conditionally Automated Vehicles
Gruden, T.; Pececnik, K.S.; Jakus, G.; Sodnik, J. Quantifying Drivers’ Physiological Responses to Take-Over Requests in Conditionally Automated Vehicles. In Proceedings of the Human-Computer Interaction Slovenia 2022, Ljubljana, Slovenia, 29 November 2022 . 22 https://doi.org/...
2022
-
[19]
Spyder-Documentation
Raybaut, P. Spyder-Documentation. 2009. Available online: https://www.spyder-ide.org/ (accessed on 26 August 2025)
2009
-
[20]
Array programming with NumPy
Harris, C.R.; Millman, K.J.; Van Der Walt, S.J.; Gommers, R.; Virtanen, P.; Cournapeau, D.; Oliphant, T.E. Array programming with NumPy. Nature 2020, 585, 357 –362. https://doi.org/10.1038/s41586-020-2649-2
2020 doi
-
[21]
Bradski, G.; Kaehler, A. OpenCV. Dr. Dobb’s J. Softw. Tools 2000, 3. Available online: https://github.com/opencv/opencv/wiki/CiteOpenCV (accessed on 26 August 2025)
2000
-
[22]
SciPy 1.0: Fundamental algorithms for scientific computing in Python
Virtanen, P.; Gommers, R.; Oliphant, T.E.; Haberland, M.; Reddy, T.; Cournapeau, D.; Burovski, E.; Peterson, P.; Weckesser, W.; Bright, J.; et al. SciPy 1.0: Fundamental algorithms for scientific computing in Python. Nat. Methods 2020, 17, 261–272. https://doi.org/10.1038/s415...
2020 doi
-
[23]
Scikit-learn: Machine learning in Python
Pedregosa, F.; Varoquaux, G.; Gramfort, A.; Michel, V.; Thirion, B.; Grisel, O.; Blondel, M.; Prettenhofer, P.; Weiss, R.; Dubourg, V.; et al. Scikit-learn: Machine learning in Python. J. Mach. Learn. Res. 2011, 12, 2825–2830
2011
-
[24]
The Python Library Reference, Release 3.8
Van Rossum, G. The Python Library Reference, Release 3.8. 2 .; Python Software Foundation : Beaverton, OR, USA, 2020
2020
-
[25]
Validation of the Empatica E4 wristband
McCarthy, C.; Pradhan, N.; Redpath, C.; Adler, A. Validation of the Empatica E4 wristband. In Proceedings of the 2016 IEEE EMBS International Student Conference (ISC), Ottawa, ON, Canada, 29 –31 May 2016; IEEE: Piscataway, NJ, USA, 2016 ; pp. 1 –4. https://doi.org/10.1109/EMBS...
2016
-
[26]
Validity of the Empatica E4 wristband to measure heart rate variability (HRV) parameters: A comparison to electrocardiography (ECG)
Schuurmans, A.A.T.; de Looff, P.; Nijhof, K.S.; Rosada, C.; Scholte, R.H.J.; Popma, A.; Otten, R. Validity of the Empatica E4 wristband to measure heart rate variability (HRV) parameters: A comparison to electrocardiography (ECG). J. Med. Syst. 2020, 44, 1 –11. https://doi.org...
2020 doi
-
[27]
Ambulatory heart rate variability monitoring: Comparisons between the empatica e4 wristband and holter electrocardiogram
Van Voorhees, E.E.; Dennis, P.A.; Watkins, L.L.; Patel, T.A.; Calhoun, P.S.; Dennis, M.F.; Beckham, J.C. Ambulatory heart rate variability monitoring: Comparisons between the empatica e4 wristband and holter electrocardiogram. Biopsychosoc. Sci. Med. 2022, 84, 210 –214. https:...
2022 doi
-
[28]
YOLOv8 Docs by Ultralytics (Version 8.0
Jocher, G.; Chaurasia, A.; Qiu, J. YOLOv8 Docs by Ultralytics (Version 8.0. 0). [software]. Available online: https://github.com/ ultralytics/ultralytics (accessed on 26 August 2025)
2025
-
[29]
An analysis of the Viola-Jones face detection algorithm
Wang, Y.Q. An analysis of the Viola-Jones face detection algorithm. Image Process. Line 2014, 4, 128–148. https://doi.org/10.5201/ipol.2014.104
2014 doi
-
[30]
Rapid object detection using a boosted cascade of simple features
Viola, P.; Jones, M. Rapid object detection using a boosted cascade of simple features. In Proceedings of the 2001 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, CVPR 2001, Kauai, HI, USA, 8 –14 December 2001; IEEE: Piscataway, NJ, USA, 2001; Volu...
2001
-
[31]
Generalized face anti -spoofing by detecting pulse from face videos
Li, X.; Komulainen, J.; Zhao, G.; Yuen, P.C.; Pietikäinen, M. Generalized face anti -spoofing by detecting pulse from face videos. In Proceedings of the 2016 23rd International Conference on Pattern Recognition (ICPR), Cancun, Mexico, 4 –8 December 2016; IEEE: Piscataway, NJ, ...
2016
-
[32]
Digital Image Processing; Pearson Education India: Delhi, India, 2009
Gonzalez, R.C. Digital Image Processing; Pearson Education India: Delhi, India, 2009
2009
-
[33]
The architecture and performance of the face and eyes detection system based on the Haar cascade classifiers
Kasinski, A.; Schmidt, A. The architecture and performance of the face and eyes detection system based on the Haar cascade classifiers. Pattern Anal. Appl. 2010, 13, 197 –211. https://doi.org/10.1007/s10044-009-0150-5
2010 doi
-
[34]
Face Detection Accuracy Study Based on Race and Gender Factor Using Haar Cascades; CEUR Workshop Proceedings: Aachen, Germany, 2020; Volume 2667, pp
Rudinskaya, E.; Paringer, R. Face Detection Accuracy Study Based on Race and Gender Factor Using Haar Cascades; CEUR Workshop Proceedings: Aachen, Germany, 2020; Volume 2667, pp. 238–242
2020
-
[35]
Pulse rate variability analysis using remote photoplethysmography signals
Yu, S.G.; Kim, S.E.; Kim, N.H.; Suh, K.H.; Lee, E.C. Pulse rate variability analysis using remote photoplethysmography signals. Sensors 2021, 21, 6241. https://doi.org/10.3390/s21186241
2021 doi
-
[36]
Unifying frame rate and temporal dilations for improved remote pulse detection
Speth, J.; Vance, N.; Flynn, P.; Bowyer, K.; Czajka, A. Unifying frame rate and temporal dilations for improved remote pulse detection. Comput. Vis. Image Underst. 2021, 210, 103246. https://doi.org/10.1016/j.cviu.2021.103246
2021
-
[37]
Uncertainties in the analysis of heart rate variability: A systematic review
Lu, L.; Zhu, T.; Morelli, D.; Creagh, A.; Liu, Z.; Yang, J.; Rullan, A.; Clifton, L.; Pimentel, M.A.F.; Tarassenko, L.; et al. Uncertainties in the analysis of heart rate variability: A systematic review. 23 IEEE Rev. Biomed. Eng. 2023, 17, 180–196. https://doi.org/10.1109/RBM...
2023
-
[38]
Clinically accurate fetal ECG parameters acquired from maternal abdominal sensors
Clifford, G.; Sameni, R.; Ward, J.; Robinson, J.; Wolfberg, A.J. Clinically accurate fetal ECG parameters acquired from maternal abdominal sensors. Am. J. Obstet. Gynecol. 2011, 205, 47.e1– 47.e5. https://doi.org/10.1016/j.ajog.2011.02.066
2011 doi
-
[39]
Guidelines for the management of atrial fibrillation: The Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC)
Developed with the Special Contribution of the European Heart Rhythm Association (EHRA); Endorsed by the European Association for Cardio-Thoracic Surgery (EACTS); Authors/Task Force Members; Camm, A.J.; Kirchhof, P.; Lip, G.Y.H.; Schotten, U.; Savelieva, I.; Ernst, S.; Van Gel...
2010
-
[40]
The efficiency of 10 -second resting heart rate for the evaluation of short -term heart rate variability indices
Nussinovitch, U.; Elishkevitz, K.P.; Kaminer, K.; Nussinovitch, M.; Segev, S.; Volovitz, B.; Nussinovitch, N. The efficiency of 10 -second resting heart rate for the evaluation of short -term heart rate variability indices. Pacing Clin. Electrophysiol. 2011, 34, 1498 –1502. ht...
2011
-
[41]
A new algorithm for fetal heart rate detection: Fractional order calculus approach
Tanasković, I.; Miljković , N. A new algorithm for fetal heart rate detection: Fractional order calculus approach. Med. Eng. Phys. 2023, 118, 104007. https://doi.org/10.1016/j.medengphy.2023.104007
2023
-
[42]
Webcam -based, non-contact, real-time measurement for the physiological parameters of drivers
Zhang, Q.; Wu, Q.; Zhou, Y.; Wu, X.; Ou, Y.; Zhou, H. Webcam -based, non-contact, real-time measurement for the physiological parameters of drivers. Measurement 2017, 100, 311 –321. https://doi.org/10.1016/j.measurement.2017.01.007
2017 doi
-
[43]
Speed up Eulerian Video Motion Magnification
Hussain, Y.; Shkara, A.A. Speed up Eulerian Video Motion Magnification. Kurd. J. Appl. Res. 2017, 2, 14–17. https://doi.org/10.24017/science.2017.3.14
2017 doi
-
[44]
Cardiovascular Physiology Concepts; Lippincott Williams & Wilkins: Philadelphia, PA, USA, 2011
Klabunde, R. Cardiovascular Physiology Concepts; Lippincott Williams & Wilkins: Philadelphia, PA, USA, 2011
2011
-
[45]
A comparative survey of methods for remote heart rate detection from frontal face videos
Wang, C.; Pun, T.; Chanel, G. A comparative survey of methods for remote heart rate detection from frontal face videos. Front. Bioeng. Biotechnol. 2018, 6, 33. https://doi.org/10.3389/fbioe.2018.00033
2018
-
[46]
Resource Optimization of the Eulerian Video Magnification Algorithm Towards an Embedded Architecture
Lim, K.S.; Moya -Bello, E.; Chavarria -Zamora, L. Resource Optimization of the Eulerian Video Magnification Algorithm Towards an Embedded Architecture. In Proceedings of the 2021 IEEE URUCON, Montevideo, Uruguay, 24–26 November 2021; IEEE: Piscataway, NJ, USA, 2021; pp. 576–57...
2021
-
[47]
Accelerating Eulerian video magnification using FPGA
Zhang, K.; Jin, X.; Wu, A. Accelerating Eulerian video magnification using FPGA. In Proceedings of the 2017 19th International Conference on Advanced Communication Technology (ICACT), PyeongChang, Republic of Korea, 19 –22 February 2017; IEEE: Piscataway, N J, USA, 2017; pp. 5...
2017
-
[48]
Pattern Recognition and Machine Learning; Springer: New York, NY, USA, 2006; Volume 4, Number 4, p
Bishop, C.M.; Nasrabadi, N.M. Pattern Recognition and Machine Learning; Springer: New York, NY, USA, 2006; Volume 4, Number 4, p. 738
2006
-
[49]
Motion artifacts removal and evaluation techniques for functional near -infrared spectroscopy signals: A review
Huang, R.; Hong, K.S.; Yang, D.; Huang, G. Motion artifacts removal and evaluation techniques for functional near -infrared spectroscopy signals: A review. Front. Neurosci. 2022, 16, 878750. https://doi.org/10.3389/fnins.2022.878750
2022
-
[50]
Analysis and detection R -peak detection using Modified Pan-Tompkins algorithm
Sathyapriya, L.; Murali, L.; Manigandan, T. Analysis and detection R -peak detection using Modified Pan-Tompkins algorithm. In Proceedings of the 2014 IEEE International Conference on Advanced Communications, Control and Computing Technologies, Ramanathapuram, India, 8–10 May ...
2014
-
[51]
An optimally designed digital differentiator based preprocessor for R-peak detection in electrocardiogram signal
Nayak, C.; Saha, S.K.; Kar, R.; Mandal, D. An optimally designed digital differentiator based preprocessor for R-peak detection in electrocardiogram signal. Biomed. Signal Process. Control. 2019, 49, 440–464. https://doi.org/10.1016/j.bspc.2018.09.005
2019 doi
-
[52]
Physiological responses to simulated and on -road driving
Johnson, M.J.; Chahal, T.; Stinchcombe, A.; Mullen, N.; Weaver, B.; Bédard, M. Physiological responses to simulated and on -road driving. Int. J. Psychophysiol. 2011, 81, 203 –208. https://doi.org/10.1016/j.ijpsycho.2011.06.012
2011 doi
-
[53]
A Specialized System for Arrhythmia Detection for Basic Research in Cardiology
Kohlhaas, M.; Seidlmayer, L.; Kaspar, M. A Specialized System for Arrhythmia Detection for Basic Research in Cardiology. In German Medical Data Sciences: Bringing Data to Life; IOS Press: Amsterdam, The Netherlands, 2021; pp. 3–7. https://doi.org/10.3233/shti210041
2021 doi
-
[54]
Biofingerprint detection of corona 24 virus using Raman spectroscopy: A novel approach
Rumaling, M.I.; Chee, F.P.; Bade, A.; Goh, L.P.W.; Juhim, F. Biofingerprint detection of corona 24 virus using Raman spectroscopy: A novel approach. SN Appl. Sci. 2023, 5, 197. https://doi.org/10.1007/s42452-023-05419-3
2023 doi
-
[55]
Comparison of values of Pearson’s and Spearman’s correlation coefficients on the same sets of data
Hauke, J.; Kossowski, T. Comparison of values of Pearson’s and Spearman’s correlation coefficients on the same sets of data. Quaest. Geogr. 2011, 30, 87 –93. https://doi.org/10.2478/v10117-011-0021-1
2011 doi
-
[56]
A Tutorial on Principal Components Analysis ; University of Otago: Otago, New Zealand, 2002
Smith, L.I. A Tutorial on Principal Components Analysis ; University of Otago: Otago, New Zealand, 2002
2002
-
[57]
Remote photoplethysmograph signal measurement from facial videos using spatio-temporal networks
Yu, Z.; Li, X.; Zhao, G. Remote photoplethysmograph signal measurement from facial videos using spatio-temporal networks. arXiv 2019, arXiv:1905.02419. https://doi.org/10.48550/arXiv.1905.02419
-
[58]
Empatica E3—A wearable wireless multi-sensor device for real-time computerized biofeedback and data acquisition
Garbarino, M.; Lai, M.; Bender, D.; Picard, R.W.; Tognetti, S. Empatica E3—A wearable wireless multi-sensor device for real-time computerized biofeedback and data acquisition. In Proceedings of the 2014 4th International Conference on Wireless Mobile Communication and Healthca...
2014
-
[59]
Heart rate estimation from wrist- worn photoplethysmography: A review
Biswas, D.; Simões-Capela, N.; Van Hoof, C.; Van Helleputte, N. Heart rate estimation from wrist- worn photoplethysmography: A review. IEEE Sens. J. 2019, 19, 6560 –6570. https://doi.org/10.1109/JSEN.2019.2914166
2019
-
[60]
Remote photoplethysmography for heart rate measurement: A review
Xiao, H.; Liu, T.; Sun, Y.; Li, Y.; Zhao, S.; Avolio, A. Remote photoplethysmography for heart rate measurement: A review. Biomed. Signal Process. Control. 2024, 88, 105608. https://doi.org/10.1016/j.bspc.2023.105608
2024
-
[61]
Unsupervised skin tissue segmentation for remote photoplethysmography
Bobbia, S.; Macwan, R.; Benezeth, Y.; Mansouri, A.; Dubois, J. Unsupervised skin tissue segmentation for remote photoplethysmography. Pattern Recognit. Lett. 2019, 124, 82 –90. https://doi.org/10.1016/j.patrec.2017.10.017
2019 doi
-
[62]
Video- based heart rate estimation from challenging scenarios using synthetic video generation
Benezeth, Y.; Krishnamoorthy, D.; Monsalve, D.J.B.; Nakamura, K.; Gomez, R.; Mitéran, J. Video- based heart rate estimation from challenging scenarios using synthetic video generation. Biomed. Signal Process. Control. 2024, 96, 106598. https://doi.org/10.1016/j.bspc.2024.106598
2024
-
[63]
Implementation of haar cascade classifier and eye aspect ratio for driver drowsiness detection using raspberry Pi
Kamarudin, N.; Jumadi, N.A.; Mun, N.L.; Keat, N.C.; Ching, A.H.K.; Mahmud, W.M.H.W.; Morsin, M.; Mahmud, F. Implementation of haar cascade classifier and eye aspect ratio for driver drowsiness detection using raspberry Pi. Universal J. Electr. Electron. Eng. 2019, 6, 67 –75. h...
2019
-
[64]
Investigating sources of inaccuracy in wearable optical heart rate sensors
Bent, B.; Goldstein, B.A.; Kibbe, W.A.; Dunn, J.P. Investigating sources of inaccuracy in wearable optical heart rate sensors. NPJ Digit. Med. 2020, 3, 18. https://doi.org/10.1038/s41746-020-0226- 6
2020 doi
-
[65]
Validity of the Empatica E4 wristband to estimate resting-state heart rate variability in a lab-based context
Stuyck, H.; Dalla Costa, L.; Cleeremans, A.; Van den Bussche, E. Validity of the Empatica E4 wristband to estimate resting-state heart rate variability in a lab-based context. Int. J. Psychophysiol. 2022, 182, 105–118. https://doi.org/10.1016/j.ijpsycho.2022.10.003
2022 doi
-
[67]
-S.; Jäntti, H
Hartikainen, S.; Lipponen, J.A.; Hiltunen, P.; Rissanen, T.T.; Kolk, I.; Tarvainen, M.P.; Martikainen, T.J.; Castrén, M.; Väliaho, E. -S.; Jäntti, H. Effectiveness of the chest strap electrocardiogram to detect atrial fibrillation. Am. J. Cardiol. 2019, 123, 1643 –1648. https:...
2019 doi
-
[68]
Robust confidence intervals for effect sizes: A comparative study of Cohen’s d and Cliff’s delta under non -normality and heterogeneous variances
Hess, M.R.; Kromrey, J.D. Robust confidence intervals for effect sizes: A comparative study of Cohen’s d and Cliff’s delta under non -normality and heterogeneous variances. In Proceedings of the Annual Meeting of the American Educational Research Association, San Diego, CA, US...
2004
-
[69]
Mmpd: Multi-domain mobile video physiology dataset
Tang, J.; Chen, K.; Wang, Y.; Shi, Y.; Patel, S.; McDuff, D.; Liu, X. Mmpd: Multi-domain mobile video physiology dataset. In Proceedings of the 2023 45th Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC), Sydney, Australia, 24–27 July...
2023
-
[70]
Fusion method to estimate heart rate from facial videos based on RPPG and RBCG
Lee, H.; Cho, A.; Whang, M. Fusion method to estimate heart rate from facial videos based on RPPG and RBCG. Sensors 2021, 21, 6764. https://doi.org/10.3390/s21206764. 25
2021 doi
-
[71]
Non-Contact Health Monitoring During Daily Personal Care Routines
Ma, X.; Tang, J.; Jiang, Z.; Cheng, S.; Shi, Y.; Li, D.; Zhang, T.; Liu, H.; Chen, L.; Zhao, Q.; et al. Non-Contact Health Monitoring During Daily Personal Care Routines. arXiv 2025, arXiv:2506.09718. https://doi.org/10.48550/arXiv.2506.09718
2025 doi
-
[72]
Contactless heart rate estimation from face videos
Lamba, P.S.; Virmani, D. Contactless heart rate estimation from face videos. J. Stat. Manag. Syst. 2020, 23, 1275–1284. https://doi.org/10.1080/09720510.2020.1799584
2020
-
[73]
Real -time realizable mobile imaging photoplethysmography
Lee, H.; Ko, H.; Chung, H.; Nam, Y.; Hong, S.; Lee, J. Real -time realizable mobile imaging photoplethysmography. Sci. Rep. 2022, 12, 7141. https://doi.org/10.1038/s41598-022-11265-x
2022 doi
-
[74]
Imaging photoplethysmography: A real-time signal quality index
Fallet, S.; Schoenenberger, Y.; Martin, L.; Braun, F.; Moser, V.; Vesin, J.M. Imaging photoplethysmography: A real-time signal quality index. In Proceedings of the 2017 Computing in Cardiology (CinC), Rennes, France, 24 –27 September 2017; IEEE: Piscataway, NJ, USA, 2017; pp. ...
2017 doi
-
[75]
Twenty -four hour time domain heart rate variability and heart rate: Relations to age and gender over nine decades
Umetani, K.; Singer, D.H.; McCraty, R.; Atkinson, M. Twenty -four hour time domain heart rate variability and heart rate: Relations to age and gender over nine decades. J. Am. Coll. Cardiol. 1998, 31, 593–601. https://doi.org/10.1016/S0735-1097(97)00554-8
1998 doi
-
[76]
Non -contact pulse rate measurement using facial videos
Ruba, M.; Jeyakumar, V.; Gurucharan, M.K.; Kousika, V.; Viveka, S. Non -contact pulse rate measurement using facial videos. In Proceedings of the 2020 IEEE International Conference on Advances and Developments in Electrical and Electronics Engineering (ICADEE), Coimbatore, Ind...
2020
-
[77]
Non-contact video-based estimation of heart rate variability spectrogram from hemoglobin composition
Fukunishi, M.; Kurita, K.; Yamamoto, S.; Tsumura, N. Non-contact video-based estimation of heart rate variability spectrogram from hemoglobin composition. Artif. Life Robot. 2017, 22, 457–463. https://doi.org/10.1007/s10015-017-0382-1
2017 doi
-
[78]
Evaluating the Empatica E4 derived heart rate and heart rate variability measures in older men and women
Ravindran, K.K.; Della Monica, C.; Atzori, G.; Lambert, D.; Revell, V.; Dijk, D.J. Evaluating the Empatica E4 derived heart rate and heart rate variability measures in older men and women. In Proceedings of the 2022 44th Annual International Conference of the IEEE Engineering ...
2022
-
[79]
Comparison of Apple watch vs KardiaMobile: A tale of two devices
Lee, C.; Lee, C.; Fernando, C.; Chow, C.M. Comparison of Apple watch vs KardiaMobile: A tale of two devices. CJC Open 2022, 4, 939–945. https://doi.org/10.1016/j.cjco.2022.07.011
2022 doi
-
[80]
The normal range and determinants of the intrinsic heart rate in man
Jose, A.D.; Collison, D. The normal range and determinants of the intrinsic heart rate in man. Cardiovasc. Res. 1970, 4, 160–167. https://doi.org/10.1093/cvr/4.2.160
1970 doi
-
[81]
The use of heart rate in a driving simulator as an indicator of age-related differences in driver workload
Reimer, B.; Mehler, B.L.; Pohlmeyer, A.E.; Coughlin, J.F.; Dusek, J.A. The use of heart rate in a driving simulator as an indicator of age-related differences in driver workload. Adv. Transp. Stud. Int. J. 2006, 9–20. Available online: https://www.atsinternationaljournal.com/2...
2006
-
[82]
Dataset comprising extracted R, G, and B components for assessment of remote photopletismography (Version 1) [Data set]
Nešković, Đ.D.; Stojmenova Pečečnik, K.; Sodnik, J.; Miljković, N. Dataset comprising extracted R, G, and B components for assessment of remote photopletismography (Version 1) [Data set]. Zenodo 2025. https://doi.org/10.5281/zenodo.16414188
2025 doi
-
[83]
Contactless physiological signals extraction based on skin color magnification
Suh, K.H.; Lee, E.C. Contactless physiological signals extraction based on skin color magnification. J. Electron. Imaging 2017, 26, 063003. https://doi.org/10.1117/1.JEI.26.6.063003
2017 doi
-
[84]
A deep learning approach for face detection using YOLO
Garg, D.; Goel, P.; Pandya, S.; Ganatra, A.; Kotecha, K. A deep learning approach for face detection using YOLO. In Proceedings of the 2018 IEEE Punecon, Pune, India, 30 November–2 December 2018; IEEE: Piscataway, NJ, USA, 2018; pp. 1 –4. https://doi.org/10.1109/PUNECON.2018.8745376
2018
-
[85]
Skin segmentation using color pixel classification: Analysis and comparison
Phung, S.L.; Bouzerdoum, A.; Chai, D. Skin segmentation using color pixel classification: Analysis and comparison. IEEE Trans. Pattern Anal. Mach. Intell. 2005, 27, 148 –154. https://doi.org/10.1109/TPAMI.2005.17
2005 doi
-
[86]
You only look once: Unified, real -time object detection
Redmon, J.; Divvala, S.; Girshick, R.; Farhadi, A. You only look once: Unified, real -time object detection. In Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, Las Vegas, NV, USA, 27–30 June 2016; pp. 779–788. https://doi.org/10.1109/CVPR.2016.91
2016 doi
-
[87]
The Evaluation of Remote Monitoring Technology Across Participants with Different Skin Tones
Talukdar, D.; De Deus, L.F.; Sehgal, N. The Evaluation of Remote Monitoring Technology Across Participants with Different Skin Tones. Cureus 2023, 15, e45075. https://doi.org/10.7759/cureus.45075
2023 doi
-
[88]
Evaluation of Remote Monitoring Technology across 26 different skin tone participants
Talukdar, D.; de Deus, L.F.; Sehgal, N. Evaluation of Remote Monitoring Technology across 26 different skin tone participants. MedRxiv 2023, https://doi.org/10.1101/2023.04.02.23288057
2023 doi
- [89]
-
[90]
Deepfakes detection based on heart rate estimation: Single-and multi-frame
Hernandez-Ortega, J.; Tolosana, R.; Fierrez , J.; Morales, A. Deepfakes detection based on heart rate estimation: Single-and multi-frame. In Handbook of Digital Face Manipulation and Detection: From DeepFakes to Morphing Attacks ; Springer International Publishing: Cham, Switz...
2022 doi
-
[2429]
https://doi.org/10.1093/eurheartj/ehq278
Reviewed August 16, 2026 · model on record in the stance chip above.
Discussion (0). Continue with ORCID to comment.