Wireless video clock synchronization to enable power saving

摘要

In a wireless video system, the clock rate for wirelessly transmitting the video data from the transmitting device should be identical to the clock rate for receiving the video data at the receiving device. But the two devices have separate clocks, whose frequencies may drift apart over time, leading the video buffer to be over run or under run. Clock synchronizing messages to prevent this may be sent at short intervals when clock synchronization is first being acquired, and at larger intervals after clock synchronization has already been achieved and is merely being maintained.

主权项

1. A first device for communicating video data wirelessly to a second device, the first device comprising:
a processor, a memory, and a radio coupled to the processor and the memory; wherein the radio is to wirelessly communicate video data between the first and second devices; wherein the radio is to receive clock synchronization information from the second device to synchronize a first video clock in the first device with a second video clock in the second device; and wherein the clock synchronization information is to be received at intervals of a first duration during a first mode and at intervals of a second duration during a second mode, the second duration being longer than the first duration; wherein the first duration is used for clock acquisition to acquire synchronization between the first video clock and the second video clock, and the second duration is used for clock tracking to maintain synchronization between the first video clock and the second video clock; wherein the first clock and the second clock are used to communicate video information between the first device and the second device; wherein the first clock is used to communicate video data into or out of a buffer.