Analysis of audio and video synchronization in TV digital broadcast devices

From the source of the audio and video production to the final products, audio and video signals are going through series of separate audio and video devices in the chain. Each of these devices produces delay between audio and video signal. In the analogue domain, there were minimal differences in delays between audio and video signal. With a transition to a digital technology, video processing has become much more complex than audio. As a result, there occurs asynchrony between audio and video signal. To minimize this effect it is necessary to control and measure lip sync error. For lip sync measuring, as a source is used lip sync generator and an instrument that measures it at the end of the chain. Lip sync error measurements were analysed on the basis of Recommendation ITU-R.B.T. 1359. For the measurements was used the Tektronix WFM 23000 instrument.