Patent ID: 9344748
Filing Date: 2016-05-17
CPC Classification: H04N

Claim Text:
1. A system for inter-chassis synchronization between audio output streams, the system comprising: a first adaptive transcoder in a first chassis for generating multiple transcoded audio output streams from an input to the first adaptive transcoder, and synchronizing the multiple transcoded audio output streams based on corresponding segments; a second adaptive transcoder in a second chassis, the second adaptive transcoder including: the second chassis synchronizing a second group of transcoded audio output streams output from the second transcoder with a first group of transcoded audio output streams output from the first transcoder by: receiving, from the first chassis, video segment presentation time stamp and corresponding audio aligned presentation time stamp pairs for the input to the first adaptive transcoder; storing the pairs of video segment presentation time stamp and audio aligned presentation time stamp data from the first chassis to a memory location in the second chassis designated for first transcoder sync information; identifying and storing video segment presentation time stamp and corresponding audio aligned presentation time stamp pairs for the input to the second adaptive transcoder to a memory location in the second chassis designated for second transcoder sync information; for a video segment presentation time stamp received at the input to the second transcoder, searching for a first transcoder video segment presentation time stamp in the memory location designated for first transcoder sync information that matches the video segment presentation time stamp received at the input at the second transcoder compare an audio aligned presentation time stamp paired to a matching first transcoder video segment presentation time stamp to a second transcoder audio aligned presentation time stamp paired with the received video segment presentation time stamp; determine an audio sync presentation time stamp offset based on the difference between the first transcoder's audio aligned presentation time stamp to the second transcoder's audio aligned presentation time stamp; and based on the audio sync presentation time stamp offset, adjusting the presentation time stamp inserted by the audio encoder in segments of the transcoded audio output streams to synchronize the transcoded audio output streams output from the second transcoder with the transcoded audio output streams output from the first transcoder.