Playout delay of TV signals: measurement system design, validation and results

Due to new interactive TV services, synchronizing the playout of content on different TVs is becoming important. To synchronize, knowledge of delay differences is needed. In this study, a measurement system is developed to gain insight into the magnitude of delay differences of different TV setups in an automated fashion. This paper shows the measurement system, which is validated for precision and accuracy. Preliminary measurements results show that regular TV broadcasts differ up to 6 seconds in playout moment and that web based TV broadcasts can introduce more than a minute delay. Furthermore, we measured a broadcasting before encoding and modulation, which resulted in a time about 4 second before the fastest receiver. On a side note, while developing the measurement system we found out that GPS timing on consumer Android devices was inaccurate, with fluctuations of up to 1 second.