Patent ID: 8677437

Claim:
A method of determining the extent to which a plurality of media signals are out of sync with each other, the method comprising: receiving a first input media signal and a second input media signal wherein the first and second input media signals are in sync with each other, and wherein the first input media signal is a video signal and the second input media signal is an audio signal corresponding to the video signal; extracting at least one first characteristic feature from the first input media signal, the at least one first characteristic feature extracted from the first input media signal being a time-varying characteristic of the video signal; extracting at least one second characteristic feature from the second input media signal, the at least one second characteristic feature extracted from the second input media signal being a time-varying characteristic of the audio signal; receiving a first output media signal and a second output media signal wherein the first output media signal corresponds to the first input media signal after traversing a network, and the second output media signal corresponds to the second input media signal after traversing the network; extracting the at least one first characteristic feature from the first output media signal; extracting the at least one second characteristic feature from the second output media signal; calculating a first signal delay based on the at least one first characteristic feature extracted from the first input and output media signals; calculating a second signal delay based on the at least one second characteristic feature extracted from the second input and output media signals; and outputting a synchronization signal based on the difference between the first and second delay signals wherein the synchronization signal represents the extent to which the first and second output media signals are out of sync with each other.