Patents by Inventor Lujun Yuan

Lujun Yuan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7391809
    Abstract: A scalable video transcoder with limited drifting error is disclosed. The transcoder accumulates re-quantization errors of I-frames or P-frames. The accumulated errors are only selectively introduced into the transcoding loop in every block to compensate for transcoding errors. A threshold algorithm adaptively utilizes the accumulated errors at block level to control drifting error at an acceptable limited level. Transcoder complexity is scalable because a DCT transform may be removed from the transcoder loop when the accumulated errors are not used for compensation. The re-quantization process can be simply implemented by look-up table(s), which significantly reduces the complexity of the re-quantization process.
    Type: Grant
    Filed: December 30, 2003
    Date of Patent: June 24, 2008
    Assignee: Microsoft Corporation
    Inventors: Shipeng Li, Lujun Yuan, Qi Chen, Feng Wu
  • Publication number: 20050147163
    Abstract: A scalable video transcoder with limited drifting error is disclosed. The transcoder accumulates re-quantization errors of I-frames or P-frames. The accumulated errors are only selectively introduced into the transcoding loop in every block to compensate for transcoding errors. A threshold algorithm adaptively utilizes the accumulated errors at block level to control drifting error at an acceptable limited level. Transcoder complexity is scalable because a DCT transform may be removed from the transcoder loop when the accumulated errors are not used for compensation. The re-quantization process can be simply implemented by look-up table(s), which significantly reduces the complexity of the re-quantization process.
    Type: Application
    Filed: December 30, 2003
    Publication date: July 7, 2005
    Inventors: Shipeng Li, Lujun Yuan, Qi Chen, Feng Wu
  • Publication number: 20050129130
    Abstract: A coding framework that provides conversions between one or more video formats without the use of a transcoder. A video information stream that includes color information formatted in accordance with a first color space sampling format is split into a base stream and an enhanced stream. The base stream is formatted in accordance with a second color space sampling format. The enhanced stream includes enhanced information that when combined with the base stream re-constructs the first format. During encoding, the enhanced stream may be encoded using spatial information related to the base information stream. An output stream of the encoded base stream and encoded enhanced stream may be interleaved, concatenated, or include independent files for the encoded base stream and the encoded enhanced stream.
    Type: Application
    Filed: December 10, 2003
    Publication date: June 16, 2005
    Inventors: Jacky Shen, Feng Wu, Lujun Yuan, Shipeng Li