Java* Media Framework Tutorial - Lesson 3C

When presenting multiple displays simultaneously, each Player must start out at exactly the same moment. syncStart(long tbt) can be used to specify a specific future TimeBase (wall-clock) time at which the Player should start. Before this can be reliably done, prefetching must be performed on all the players. Sometimes there is a slight time delay in starting even a prefetched Player. The value of this delay is returned by getStartLatency(). The future start time for all the Players should be at least as big as the greatest start latency. Note that getStartLatency() can return different values for different Players.

To remain synchronized, every Player's internal clock must tick at the same rate as the others. Frequently this is already the case (or is close enough not to be a problem). However, to ensure this is true, setTimeBase() can be used to force all the players to synchronize to a common TimeBase. A common TimeBase can be found either by selecting one of the players and using its TimeBase (retrieved with getTimeBase()) or by using the system time base (retrieved with Manager.getSystemTimeBase()).