Back to results
US 8,509,301 B2Granted
Audio and video synchronizing method in transcoding system
AssigneeMedia Excel Korea Co. Ltd.
InventorNam Hun Jeong
Life of this patent
Estimating the term…
Abstract
Provided is an audio and video synchronizing method in a transcoding system, which compensates for lossy audio frames and lossy video frames according to a relative time at an early encoding stage, corrects a jitter of audio frames and readjusts a jitter of video frames in order to correspond to the audio frames having the corrected jitter at a multiplexing stage that is a later encoding stage, thereby minimizing a variation of the duration of the video frames and preventing audio and video from being unsynchronized when a media file is reproduced.
Claims11
An audio and video synchronizing method in a transcoding system comprising:
- receiving data including encoded audio frames and encoded video frames;
- de-multiplexing the data to obtain audio frames and video frames;
- decoding the audio frames and the video frames;
- detecting lossy frames of the decoded audio frames and the decoded video frames by using audio time stamp information included in the decoded audio frames and video time stamp information included in the decoded video frames;
- compensating for the lossy frames by comparing relative times of the lossy audio frames and the lossy video frames;
- encoding the compensated audio frames and the compensated video frames;
- and
- multiplexing the encoded audio frames and the encoded video frames,
- wherein the compensating for the lossy frames comprises:
- if the lossy audio frames are greater than the lossy video frames, inserting as many mutes as lengths of the video frames corresponding to the lossy audio frames into the lossy audio frames,
- if the lossy video frames are greater than the lossy audio frames,
- calculating a number of the video frames corresponding to lengths of the lossy audio frames;
- and
- duplicating as many video frames right before a loss occurs as the calculated number of the video frames to compensate for the lossy video frames.
11 more elements
A transcoding system comprising:
- a de-multiplexer for receiving data including encoded audio frames and encoded video frames, and de-multiplexing the data to audio frames and video frames;
- a decoding unit comprising an audio decoder for decoding the audio frames and a video decoder for decoding the video frames;
- a lossy frame compensation unit for detecting lossy frames of the decoded audio frames and the decoded video frames by using audio time stamp information included in the decoded audio frames and video time stamp information included in the decoded video frames, and compensating for the lossy frames by comparing relative times of the lossy audio frames and the lossy video frames;
- an encoding unit comprising an audio encoder for encoding the compensated audio frames and a video encoder for encoding the compensated video frames;
- and
- a multiplexing unit for multiplexing the encoded audio frames and the encoded video frames,
- wherein the lossy frame compensation unit comprises:
- a lossy frame detection unit for detecting lossy frames of the decoded audio frames and the decoded video frames by using audio time stamp information included in the decoded audio frames and video time stamp information included in the decoded video frames;
- an audio mute insertion unit for, if the lossy audio frames are greater than the lossy video frames, inserting as many mutes as lengths of the video frames corresponding to the lossy audio frames into the lossy audio frames;
- and
- a video frame duplication unit for, if the lossy video frames are greater than the lossy audio frames, calculating a number of the video frames corresponding to lengths of the lossy audio frames, and duplicating as many video frames right before a loss occurs as the calculated number of the video frames to compensate for the lossy video frames.
8 more elements
Dependencies are inferred from the claim text.