Patents by Inventor Lidong Xu

Lidong Xu 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).

  • Publication number: 20110002389
    Abstract: Methods and systems to apply motion estimation (ME) based on reconstructed reference pictures in a B frame or in a P frame at a video decoder. For a P frame, projective ME may be performed to obtain a motion vector (MV) for a current input block. In a B frame, both projective ME and mirror ME may be performed to obtain an MV for the current input block. The ME process can be performed on sub-partitions of the input block, which may reduce the prediction error without increasing the amount of MV information in the bitstream. Decoder-side ME can be applied for the prediction of existing inter frame coding modes, and traditional ME or the decoder-side ME can be adaptively selected to predict a coding mode based on a rate distribution optimization (RDO) criterion.
    Type: Application
    Filed: September 25, 2009
    Publication date: January 6, 2011
    Inventors: Lidong Xu, Yi-Jen Chiu, Wenhao Zhang
  • Publication number: 20110002387
    Abstract: Techniques are described that can be used to apply motion estimation (ME) based on reconstructed reference pictures in a B frame or in a P frame at a video decoder. For a P frame, projective ME may be performed to obtain a motion vector (MV) for a current input block. In a B frame, both projective ME and mirror ME may be performed to obtain an MV for the current input block. A metric an be used determining a metric for each pair of MV0 and MV1 that is found in the search path, where the metric is based on a combination of a first, second, and third metrics. The first metric is based on temporal frame correlation, a second metric is based on spatial neighbors of the reference blocks, and a third metric is based on the spatial neighbors of the current block.
    Type: Application
    Filed: January 14, 2010
    Publication date: January 6, 2011
    Inventors: Yi-Jen Chiu, Lidong Xu, Wenhao Zhang
  • Publication number: 20110002390
    Abstract: Method and apparatus for deriving a motion vector at a video decoder. A block-based motion vector may be produced at the video decoder by utilizing motion estimation among available pixels relative to blocks in one or more reference frames. The available pixels could be, for example, spatially neighboring blocks in the sequential scan coding order of a current frame, blocks in a previously decoded frame, or blocks in a downsampled frame in a lower pyramid when layered coding has been used.
    Type: Application
    Filed: September 25, 2009
    Publication date: January 6, 2011
    Inventors: Yi-Jen Chiu, Lidong Xu, Hong Jiang
  • Publication number: 20100254448
    Abstract: An adaptive Wiener filter may be applied to improve coding efficiency because of information lost during quantization of the video encoding process. The Wiener filter may be selectively applied globally to an entire picture or locally to portions of the picture. Histogram segmentation may be used to select pixels for Wiener filtering in some embodiments. The Wiener filter may be adaptively applied to histogram bins, improving coding efficiency in some cases.
    Type: Application
    Filed: April 6, 2009
    Publication date: October 7, 2010
    Inventors: Lidong Xu, Yi-Jen Chu, Wenhao Zhang
  • Publication number: 20100008427
    Abstract: Techniques are described that can be used to either compress or expand video. Color compression techniques are described that can be used to compress the wide color gamut content into lower color gamut for inclusion in a baseline layer. Color expansion techniques are described that convert lower color gamut data into wider color gamut format for inclusion in an enhancement layer. Both of the baseline video stream and enhancement layer video streams may be transmitted through a channel or stored in a memory device to be viewed later. Accordingly, both baseline and enhancement video layers are available so that either lower or higher quality displays can be used to display video.
    Type: Application
    Filed: September 11, 2008
    Publication date: January 14, 2010
    Inventors: Yi-Jen Chiu, Hong Jiang, Lidong Xu, Ya-Ti Peng
  • Publication number: 20100008417
    Abstract: Techniques are described that can be used to determine parameters of an adaptive Wiener filter to apply to a video region. The following parameters of the Wiener filter may be adjusted: coefficients, coefficient quantization, filter type, filter size, prediction mode, entropy encoding, and number of filter tables. The parameters associated with the lowest rate distortion cost of the encoder are selected for transmission with the encoded video. If not using adaptive Wiener filtering results in a lowest rate distortion cost, then adaptive Wiener filtering is not used for the video region. If using adaptive Wiener filtering results in a lowest rate distortion cost, then the parameters applied by the adaptive Wiener filtering that result in the lowest rate distortion cost are communicated with the filtered video region.
    Type: Application
    Filed: July 9, 2008
    Publication date: January 14, 2010
    Inventors: Lidong Xu, Yi-Jen Chiu
  • Publication number: 20090262798
    Abstract: A scalable video codec may convert lower bit depth video to higher bit depth video using decoded lower bit depth video for tone mapping and tone mapping derivation. The conversion can also use the filtered lower bit depth video for tone mapping and tone mapping derivation.
    Type: Application
    Filed: April 16, 2008
    Publication date: October 22, 2009
    Inventors: Yi-Jen Chiu, Lidong Xu, Hong Jiang
  • Publication number: 20090257486
    Abstract: Adaptive filtering may be used to increase the quality of tone mapped, baseline layer encoded information. As a result, scalable video codecs may be implemented with improved picture quality in some embodiments.
    Type: Application
    Filed: April 11, 2008
    Publication date: October 15, 2009
    Inventors: Yi-Jen Chiu, Lidong Xu
  • Publication number: 20090257670
    Abstract: A video encoder may use an adaptive Wiener filter inside the core video encoding loop to improve coding efficiency. In one embodiment, the Wiener filter may be on the input to a motion estimation unit and, in another embodiment, it may be on the output of a motion compensation unit. The taps for the Wiener filter may be determined based on characteristics of at least a region of pixel intensities within a picture. Thus, the filtering may be adaptive in that it varies based on the type of video being processed.
    Type: Application
    Filed: April 9, 2008
    Publication date: October 15, 2009
    Inventors: Yi-Jen Chiu, Lidong Xu