Sitting in front of your computer could soon be the fastest way to receive a medical check up, replacing visits to the local doctor. Massachusetts Institute of Technology student Ming-Zher Poh has created a pulse-monitoring system that works on a low-cost, low-resolution webcam. A version of the system built into a mirror has been developed which displays pulse rate at the bottom in real-time, and work is underway to add respiration and blood-oxygen level monitoring using the same technique.
Developed in collaboration with Media Lab student Daniel McDuff and Professor of Media Arts and Sciences Rosalind Picard, the system uses facial brightness recognition techniques to determine the flow of blood in the face vessels and then derives the data to produce an accurate pulse reading. A major challenge for the students was to overcome a person’s movement and different light variations. Poh successfully adapted a signal processing technique, commonly used to highlight a single voice from within a room full of people talking, to extract the pulse signal independently from the light and movement factors. The system was able to derive an accurate pulse rate from a subject moving out of frame and also from three people at the same time, simultaneously displaying the data at the bottom of the mirror.
Whilst the application of medical video monitoring is nothing new, the use of a low-resolution camera is and will provide access to a large user group. As the system works without attaching any sensors to the body it could prove useful in difficult medical situations such as with burns victims. More commonly it would prove popular for the older community or heart disease sufferers whom need to constantly monitor their blood pressure. Or perhaps you may simply want to keep track of your health and have the system installed into your bathroom mirror to check your vitals as you brush your teeth before a good night’s sleep.