We present a system that is capable of capturing, processing and displaying High Dynamic Range (HDR) videos at 23 frames per second. For each frame in the video, a sequence of regular images is captured in quick succession at optimally chosen shutter speeds. Intermediate camera motion is compensated and the images are combined into an HDR frame which is tone mapped for display. Our system makes use of novel algorithms that are fast enough for processing the frames in real-time. The most time-consuming operations are parallelized and executed on a graphics card for a speed-up of 15 to 1 over the sequential version.