Video and audio synchronisation

A screensnap image of Paul counting on his fingers.

A video of Paul counting down from five to one on his fingers - the audio and video are quite well synchronised (1.5MB Video).(video capture from screen)

To test how the audio and video streams are performing we do a simple five-finger test. This involves counting down from five to one using your fingers. The idea behind it is simple – the audio and video streams are being run but different processes so they can lag or get out of sync – in fact we might expect this to happen as different encoding algorithms are being used to process the audio and video data. However, as you can see from the attached video they seem to be in sync, this makes conversation a lot easier. Paul’s video camera is running at half PAL (320 x 240 pixels) and 5 frames per second, with a constant bit rate of 200Kbps.