Demonstration of vDelay: A Tool to Measure Capture-to-Display Latency and Frame Rate

We present vDelay, a tool for measuring the capture-to-display latency (CDL) and frame-rate of real-time video applications such as video chat and conferencing. Real-time video chat applications have three key software components: a video encoder that compresses the video captured from the camera, a video decoder that decompresses the video received over the network, and a playout buffer that smooths the playout of received video due to network delay variations. These software components impact capture-to-display latency (CDL) and frame-rate of the real-time video played at a receiver application. Capture-to-display latency is the total time to encode and decode a video frame, playout buffer time, and latency of the network path. Along with bit-rate, these two metrics provide quick insights into the performance of a real-time video application.