Е-Публикации
Технически университет - София

Abstract: This study evaluates the feasibility of using two affordable thermal cameras (UNI-T UTi260M and UTi260T), which are not designed as automotive sensors, for observing pedestrians and warm objects during night-time driving under low-illumination conditions. The experimental setup includes mounting the camera on the vehicle body (e.g., side mirror area/roof), recording road scenes in urban and rural environments, and selecting representative frames for qualitative and quantitative analysis. The study assesses: (i) observable pedestrian detectability in unlit road sections and under oncoming headlight glare, where visible cameras often lose contrast; (ii) the influence of low ambient temperature and strong cold wind on image appearance (including “whitening”/contrast shifts); and (iii) workflow differences, where UTi260M relies on a smartphone application for streaming/recording, while UTi260T supports PC-based image analysis and temperature-profile visualization. In addition, a calibration-based geometric method is proposed for approximate pedestrian distance estimation from single frames using silhouette pixel height and a regression model based on 1 (Formula presented.), valid for a specific mounting configuration and a known subject height. Results indicate that both cameras can highlight warm objects relative to the background and support visual pedestrian identification at low illumination, including in the presence of oncoming headlights, with UTi260M showing more stable behavior in parts of the tests. This work is a feasibility study and does not claim Advanced Driver Assist Systems (ADAS) functionality; it outlines limitations, repeatability considerations, and a minimal set of metrics and procedures for future extension. All quantitative indicators derived from exported frames are explicitly treated as image-level proxy metrics, not as physical sensor characteristics.

References

1. Alldieck T. Bahnsen C. Moeslund T. Context-Aware Fusion of RGB and Thermal Imagery for Traffic Monitoring Sensors 2016 16 1947 10.3390/s16111947
2. Pettirsch A. Garcia-Hernandez A. New generation thermal traffic sensor: A novel dataset and monocular 3D thermal vision framework Knowl.-Based Syst. 2025 315 113334 10.1016/j.knosys.2025.113334
3. Dona R. Mattas K. Vass S. Delubac G. Matias J. Tinnes S. Ciuffo B. Thermal Cameras and Their Safety Implications for Pedestrian Protection: A Mixed Empirical and Simulation-Based Characterization Transp. Res. Rec. 2025 2679 404 421 10.1177/03611981241278346
4. Wessapan T. Rattanadecho P. Influence of ambient temperature on heat transfer in the human eye during exposure to electromagnetic fields at 900 MHz Int. J. Heat Mass Transf. 2014 70 378 388 10.1016/j.ijheatmasstransfer.2013.11.009
5. Kulacki F.A. Acharya S. Chudnovsky Y. Cotta R.M. Devireddy R. Dhir V.K. Mengüç M.P. Mostaghimi J. Vafai K. Handbook of Thermal Science and Engineering Springer Berlin/Heidelberg, Germany 2018 10.1007/978-3-319-26695-4
6. Hall J.E. Michael E. Guyton and Hall Textbook of Medical Physiology Elsevier Health Sciences Amsterdam, The Netherlands 2026 978-0-443-11101-3, 978-0-443-28109-9
7. Tasgaonkar P.P. Garg R.D. Garg P.K. Vehicle Detection and Traffic Estimation with Sensors Technologies for Intelligent Transportation Systems Sens. Imaging 2020 21 29 10.1007/s11220-020-00295-2
8. Yawale A.D. Raskar V.B. Pedestrain detection by video processing using thermal and night vision system Int. J. Eng. Sci. Res. Technol. 2017 6 29 38 10.5281/zenodo.229856
9. Yoneyama A. Yeh C.-H. Kuo C.-C.J. Robust vehicle and traffic information extraction for highway surveillance EURASIP J. Adv. Signal Process. 2005 2005 912501 10.1155/ASP.2005.2305
10. Iwasaki Y. Kawata S. Nakamiya T. Vehicle detection even in poor visibility conditions using infrared thermal images and its application to road traffic flow monitoring Emerging Trends in Computing, Informatics, Systems Sciences, and Engineering Sobh T. Elleithy K. Springer Science+Business Media New York, NY, USA 2013 997 1009
11. Casado-Sanz N. Guirao B. Galera A.L. Attard M. Investigating the Risk Factors Associated with the Severity of the Pedestrians Injured on Spanish Crosstown Roads Sustainability 2019 11 5194 10.3390/su11195194
12. Zangenehpour S. Miranda-Moreno L.F. Saunier N. Automated classification based on video data at intersections with heavy pedestrian and bicycle traffic: Methodology and application Transp. Res. Part C Emerg. Technol. 2015 56 161 176 10.1016/j.trc.2015.04.003
13. Fu T. Stipancic J. Zangenehpour S. Miranda-Moreno L. Saunier N. Automatic Traffic Data Collection under Varying Lighting and Temperature Conditions in Multimodal Environments: Thermal versus Visible Spectrum Video-Based Systems J. Adv. Transp. 2017 2017 5142732 10.1155/2017/5142732
14. Available online: https://science.nasa.gov/ems/09_visiblelight/ (accessed on 10 March 2026)
15. Faundez-Zanuy M. Mekyska J. Espinosa-Duro V. On the focusing of thermal images Pattern Recognit. Lett. 2011 32 1548 1557 10.1016/j.patrec.2011.04.022
16. Available online: https://www.icnirp.org/en/frequencies/infrared/index.html (accessed on 10 March 2026)
17. Beg M.S. Ismail M.Y. Badrulhisam N.H. Siswanto I. Gunadi G. Improving Vehicle Assistance Systems: Evaluation of Augmented Capabilities through Infrared Thermal Camera Integration Int. J. Automot. Mech. Eng. 2025 22 12236 12252 10.15282/ijame.22.1.2025.20.0937
18. Farooq M.A. Shariff W. O’Callaghan D. Merla A. Corcoran P. On the Role of Thermal Imaging in Automotive Applications: A Critical Review IEEE Access 2023 11 25152 25173 10.1109/ACCESS.2023.3255110
19. Tashev A. Dimitrov E. Investigation of LPG influence on cylinder pressure of VW 1.9D diesel engine operating in dual-fuel mode AIP Conf. Proc. 2025 3274 060003 10.1063/5.0258924
20. Mitev P. Development of a Training Station for the Orientation of Dice Parts with Machine Vision Eng. Proc. 2024 70 57 10.3390/engproc2024070057
21. Wolf A. Pezoa J.E. Figueroa M. Modeling and Compensating Temperature-Dependent Non-Uniformity Noise in IR Microbolometer Cameras Sensors 2016 16 1121 10.3390/s16071121
22. König S. Gutschwager B. Taubert R.D. Hollandt J. Metrological characterization and calibration of thermographic cameras for quantitative temperature measurement J. Sens. Sens. Syst. 2020 9 425 442 10.5194/jsss-9-425-2020
23. Igual J. Photographic Noise Performance Measures Based on RAW Files Analysis of Consumer Cameras Electronics 2019 8 1284 10.3390/electronics8111284
24. Lee H. Kang M.G. Infrared Image Deconvolution Considering Fixed Pattern Noise Sensors 2023 23 3033 10.3390/s23063033 36991744

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