As humans are homeothermic, our internal temperature is closely linked with numerous physiological and psychological mechanisms. Given this, human thermal patterns have been explored to improve the understandings of our body for a couple of centuries (Cho, 2019). Researchers have shown that physiological signatures can be captured via non-contact thermal imaging (e.g. respiration monitoring in Cho et al. 2017). Whilst other contactless sensing methods, such as, RGB camera-based photo-plethysmography suffer from illumination and privacy issues, thermography is much less affected by those constraints (Lloyd, 2013). In addition, studies have shown that different types of physiological activities can be read through the use of a thermal imaging channel (Garbey et al., 2007, Pavlidis et al., 2012, Cho et al. 2017-2019), including respiratory, cardiovascular, perspiratory responses.
In our lab, we have been mainly investigating how to improve reliability, accuracy in physiological measurements through thermal imaging (to support real-world situations). At the same time, we have been building remote PPG (photo-plethysmography) algorithms using normal RGB cameras.
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2. Cho, Y., Julier, S. J., Marquardt, N. & Bianchi-Berthouze, N. Robust tracking of respiratory rate in high-dynamic range scenes using mobile thermal imaging. Biomed. Opt. Express, BOE 8, 4480–4503 (2017).
3. Cho, Y. Automated Mental Stress Recognition through Mobile Thermal Imaging. in the 7th International Conference on Affective Computing and Intelligent Interaction, ACII 2017 596–600 (2017).
4. Garbey, M., Sun, N., Merla, A. & Pavlidis, I. Contact-Free Measurement of Cardiac Pulse Based on the Analysis of Thermal Imagery. IEEE Transactions on Biomedical Engineering 54, 1418–1426 (2007).
5. Pavlidis, I. et al. Fast by Nature – How Stress Patterns Define Human Experience and Performance in Dexterous Tasks. Sci Rep 2, (2012).
6. Lloyd, J. M. Thermal Imaging Systems. (Springer Science & Business Media, 2013).