Measuring glass-to-glass video-conference latency

Client: John Bain, Cisco <jbain@cisco.com>

A key consideration in the design of video-conferencing systems is to minimise the latency added to the video and audio, since this can have a marked effect on the naturalness of communication. Many software solutions exist for measuring various aspects of the system latency, but there is no substitute for end-to-end (often called glass-to-glass, referring to the lens of the camera and display screen) measurements of video and audio latency. This type of measurement has traditionally been subjectively measured by humans, and is hence prone to error and bias. Your task is to automate this by presenting an audio plus video signal to one end of a video-conference link, and measure the latency of the screen/speaker output at the other end. The two ends may be geographically separated - even in different continents. The Altera teaching board will be used to provide I/O facilities. Some technical ingenuity will be involved in ensuring that any delays or offsets in measurement are accounted for.