biosignals

You can measure your heart rate with just a video of your face. No wearables, no fingertip sensors, just your webcam. I used remote photoplethysmography to track tiny color changes in the skin from blood flow. Got ~98% accuracy. Still blows my mind that a webcam can do this. [Video, 0:07, showing a pulse oximeter device clipped to a finger, displaying %SpO2 99 and PR bpm 70, next to a laptop keyboard/webcam setup — presumably ground-truth comparison for the video-based heart-rate measurement.]