Patent ID: 8238726

Claim:
An audio-video data synchronization method of synchronizing audio outputted from an audio output device and video outputted from a video output device in an audio-video output system including the audio output device and the video output device which are interconnected via a predetermined interface, wherein the interface is capable of: unidirectionally transmitting video data from the audio output device to the video output device; unidirectionally transmitting, from the video output device to the audio output device, display identification data that indicates a reproduction capability of the video output device and connection validity status information that indicates validity status of a connection of the video output device; and bidirectionally transmitting a control message, said audio-video data synchronization method comprising: authenticating with the video output device when the indication of the connection validity status information changes from Invalid to Valid; sending the video data from the audio output device to the video output device via the interface while the connection validity status information indicates Valid, while the authentication performed in said authenticating is succeeding; outputting the video from the video output device, using the video data sent in said sending; obtaining, by the audio output device, a first latency that is a period of time taken for the video output device to output the video, by receiving the display identification data that includes information indicating the first latency from the video output device via the interface when the indication of the connection validity status information changes from Invalid to Valid; adjusting, by the audio output device, timing of outputting the audio according to the first latency obtained in said obtaining of a first latency; obtaining, by the video output device, a second latency which is a period of time taken to output the video in said outputting; notifying the audio output device of the second latency by sending a control message from the video output device via the interface when the connection validity status information indicates Valid, the control message including information that indicates the second latency obtained in said obtaining of a second latency; and adjusting, by the audio output device, timing of outputting the audio according to the second latency notified in said notifying.