Measuring Heart and Breath Rates by Image Photoplethysmography using Wavelets Technique

This paper presents a method for contactless measuring of heart and respiratory rates by Photoplethysmography image technique through wavelets. This method is imperceptible to the humans, with the additional advantages of a low computational cost and high tolerance to artifacts. The approach uses the analysis of the plethysmographic signal collected by a standard color camera to estimate the heart and breathing rates. This system uses a pre-filter to reduce the offset of the averaged signal through numerical analysis techniques and the signal is processed by wavelets. Additionally, the measurement of respiration rate is decoupled from the sinus arrhythmia. A good estimate of the vital signs on ten individuals was obtained. The Bland-Altman analysis shows a strong correlation between measurements by standard systems and our approach.