Patent ID: 7664057

Claim:
A method of synchronizing streams of packets of audio data and video data over a network, comprising: accepting a plurality of streams of packets of audio data from pairs of streams of packets of audio and video data, each stream of packets of audio data in each pair synchronized with the video data of the pair, such that each stream of packets of audio data includes a respective timestamp that is synchronized with a respective timestamp of a respective matching stream of packets of video data, the streams of audio and video data packets in one pair using timestamps that may be independent of the timestamps used in the streams of audio and video data packets of any other pair; mixing the accepted streams of packets of audio data at a mixing time to form a combined stream of packets of synchronized mixed audio data having a mixing timestamp; forming timing information that relates the values at or prior to the mixing time of the respective timestamps of the packets of the audio data of the accepted streams being mixed at the mixing time, such that the relationship at a later time of the mixing timestamp with the timestamps of the individual streams being mixed is derivable; and transmitting the combined stream, at least one of the plurality of streams of packets of video data whose audio data is mixed into the transmitted combined stream, and the formed timing information over the network; such that a receiver, coupled to the network, receiving the timing information, the combined stream, and the at least one of the plurality of streams of packets of video data can use the formed timing information to synchronize the respective video data of the at least one stream of the plurality of streams of packets of video data with the mixed audio data of said combined stream, and such that no common network clock is needed for the mixing and no common network clock is needed to synchronize the respective video data of the at least one stream of the plurality of streams of packets of video data with the mixed audio data of said combined stream.