Patents by Inventor Changcai Lai

Changcai Lai 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: 9979965
    Abstract: The present disclosure discloses a method for coding an image, a method for decoding an image, a method for processing image data, and devices thereof. The method for coding the image includes determining a current intra coding block that uses a constrained intra prediction method among current inter coded frames; determining that neighboring coding blocks that are adjacent to the current intra coding block include a neighboring inter coding block; updating image data in the neighboring inter coding block based on an invariable value or image data in a neighboring intra coding block included in the neighboring coding blocks; and coding the current intra coding block based on the updated image data in the neighboring inter coding block. Using the methods and devices, the error recovery capability of an intra coding block may be improved, and the image data decoding quality may be improved.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: May 22, 2018
    Assignee: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Changcai Lai, Yongbing Lin, Xiaozhen Zheng
  • Publication number: 20170272760
    Abstract: The present disclosure provides a method for encoding an intra-frame prediction mode, including: obtaining an intra-frame prediction mode of a current intra-frame encoding block from a preset prediction mode set; obtaining reference prediction modes of the current intra-frame encoding block, where the reference prediction modes are intra-frame prediction modes of available adjacent blocks of the current intra-frame encoding block or prediction modes in a preset backup reference mode set; writing a first flag bit into a code stream according to the reference prediction modes and the intra-frame prediction mode; and, when the intra-frame prediction mode of the encoding block is different from all the reference prediction modes, obtaining a prediction mode encoding value according to a size relationship between the value of the intra-frame prediction mode and values of the reference prediction modes, and encoding the prediction mode encoding value.
    Type: Application
    Filed: June 7, 2017
    Publication date: September 21, 2017
    Applicant: HUAWEI TECHNOLOGIES CO.,LTD.
    Inventor: Changcai Lai
  • Patent number: 9769474
    Abstract: The present disclosure provides a method for encoding an intra-frame prediction mode, including: obtaining an intra-frame prediction mode of a current intra-frame encoding block from a preset prediction mode set; obtaining reference prediction modes of the current intra-frame encoding block, where the reference prediction modes are intra-frame prediction modes of available adjacent blocks of the current intra-frame encoding block or prediction modes in a preset backup reference mode set; writing a first flag bit into a code stream according to the reference prediction modes and the intra-frame prediction mode; and, when the intra-frame prediction mode of the encoding block is different from all the reference prediction modes, obtaining a prediction mode encoding value according to a size relationship between the value of the intra-frame prediction mode and values of the reference prediction modes, and encoding the prediction mode encoding value.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: September 19, 2017
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Changcai Lai
  • Publication number: 20170155925
    Abstract: An apparatus including a memory operably coupled to a processor. The processor is configured to determine whether to use an intra smoothing filter for a rectangular prediction unit (PU) based on a lookup table (LUT) used for square PUs, wherein a width of the rectangular PU is not equal to a height of the rectangular PU.
    Type: Application
    Filed: February 14, 2017
    Publication date: June 1, 2017
    Inventors: Guichen Li, Lingzhi Liu, Changcai Lai, Nam Ling, Jianhua Zheng, Chen-Xiong Zhang
  • Patent number: 9602839
    Abstract: An apparatus comprising a processor configured to determine whether to use an intra smoothing filter for a rectangular prediction unit (PU) based on a lookup table (LUT) used for square PUs, wherein a width of the rectangular PU is not equal to a height of the rectangular PU.
    Type: Grant
    Filed: May 18, 2012
    Date of Patent: March 21, 2017
    Assignee: Futurewei Technologies, Inc.
    Inventors: Guichun Li, Lingzhi Liu, Changcai Lai, Nam Ling, Jianhua Zheng, Chen-Xiong Zhang
  • Publication number: 20170019667
    Abstract: The present disclosure discloses a method for coding an image, a method for decoding an image, a method for processing image data, and devices thereof. The method for coding the image includes determining a current intra coding block that uses a constrained intra prediction method among current inter coded frames; determining that neighboring coding blocks that are adjacent to the current intra coding block include a neighboring inter coding block; updating image data in the neighboring inter coding block based on an invariable value or image data in a neighboring intra coding block included in the neighboring coding blocks; and coding the current intra coding block based on the updated image data in the neighboring inter coding block. Using the methods and devices, the error recovery capability of an intra coding block may be improved, and the image data decoding quality may be improved.
    Type: Application
    Filed: September 28, 2016
    Publication date: January 19, 2017
    Inventors: Changcai Lai, Yongbing Lin, Xiaozhen Zheng
  • Publication number: 20160323585
    Abstract: Embodiments of the present invention provide a video coding method for INTRA and a video coding apparatus. The method includes performing a traversal prediction on a current-layer coding unit CU, a prediction mode of a sub-Cu that is divided, from the current-layer CU, and a syntax element that is needed for coding of the current-layer CU; and if the best CU division mode is to divide the current-layer CU into four sub-CUs whose depth is N+1, and prediction modes of the four sub-CUs whose depth is N+1 are the same, performing coding, by using the current-layer CU as a coding unit, on the current-layer CU according to the best CU division mode, the prediction mode of the sub-CU that is divided from the current-layer CU according to the best CU division mode, and the syntax element that is needed for coding of the current-layer CU.
    Type: Application
    Filed: July 7, 2016
    Publication date: November 3, 2016
    Inventors: Haichang Zhai, Yuanwen Liu, Changcai Lai, Yang Song
  • Patent number: 9485504
    Abstract: The present invention discloses a method for coding an image, a method for decoding an image, a method for processing image data, and devices thereof. The method for coding the image includes: determining a current intra coding block that uses a constrained intra prediction method among current inter coded frames; determining that neighboring coding blocks that are adjacent to the current intra coding block include a neighboring inter coding block; updating image data in the neighboring inter coding block based on an invariable value or image data in a neighboring intra coding block included in the neighboring coding blocks; and coding the current intra coding block based on the updated image data in the neighboring inter coding block. By using the methods and devices, the error recovery capability of an intra coding block may be improved, and the image data decoding quality may be improved.
    Type: Grant
    Filed: July 10, 2013
    Date of Patent: November 1, 2016
    Assignee: Huawei Technologies Co., LTD.
    Inventors: Changcai Lai, Yongbing Lin, Xiaozhen Zheng
  • Patent number: 9179148
    Abstract: A method comprising receiving a plurality of reference pixels, computing a plurality of filter coefficients based on differences between a reference pixel and neighboring reference pixels in the plurality of reference pixels, and combining the filter coefficients with the reference pixel and the neighboring reference pixels to generate a filtered value, wherein the filtered value is used for intra prediction.
    Type: Grant
    Filed: June 13, 2012
    Date of Patent: November 3, 2015
    Assignees: Futurewei Technologies, Inc., Santa Clara University
    Inventors: Guichun Li, Lingzhi Liu, Changcai Lai, Nam Ling, Jianhua Zheng, Chen-Xiong Zhang
  • Publication number: 20150312596
    Abstract: An image processing method and apparatus, the image processing method including receiving a first largest coding unit of an image, where the first largest coding unit is a currently received largest coding unit; determining a compensation parameter of the first largest coding unit; performing pixel compensation on at least one area of the first largest coding unit according to the compensation parameter of the first largest coding unit; and performing pixel compensation on at least one area, on which pixel compensation is not performed, of a second largest coding unit according to a compensation parameter of the second largest coding unit, where the second largest coding unit is a previously received largest coding unit adjacent to the first largest coding unit.
    Type: Application
    Filed: July 8, 2015
    Publication date: October 29, 2015
    Inventors: Guiming Liao, Gang Su, Changcai Lai
  • Publication number: 20140126633
    Abstract: A method for pixel prediction is provided. The method includes: obtaining an average pixel value of reference pixel points on a long side of a current block if the current block is rectangular and coded or decoded adjacent blocks of the current block are all available, where the reference pixel points are all located at boundaries of the adjacent blocks near the current block; and obtaining a prediction pixel value of the current block according to the average pixel value of the reference pixel points on the long side. According to the pixel prediction method and apparatus provided in the embodiments of the present invention, a prediction pixel is obtained from corresponding adjacent blocks according to a shape of the current block, meeting a pixel distribution rule.
    Type: Application
    Filed: November 25, 2013
    Publication date: May 8, 2014
    Applicant: Huawei Technologies Co., Ltd.
    Inventors: Yongbing LIN, Changcai LAI
  • Publication number: 20140112388
    Abstract: The present disclosure provides a method for encoding an intra-frame prediction mode, including: obtaining an intra-frame prediction mode of a current intra-frame encoding block from a preset prediction mode set; obtaining reference prediction modes of the current intra-frame encoding block, where the reference prediction modes are intra-frame prediction modes of available adjacent blocks of the current intra-frame encoding block or prediction modes in a preset backup reference mode set; writing a first flag bit into a code stream according to the reference prediction modes and the intra-frame prediction mode; and, when the intra-frame prediction mode of the encoding block is different from all the reference prediction modes, obtaining a prediction mode encoding value according to a size relationship between the value of the intra-frame prediction mode and values of the reference prediction modes, and encoding the prediction mode encoding value.
    Type: Application
    Filed: December 27, 2013
    Publication date: April 24, 2014
    Applicant: Huawei Technologies Co., Ltd.
    Inventor: Changcai LAI
  • Publication number: 20130301715
    Abstract: The present application provides a prediction method for use in an image block encoding or decoding process. The method includes obtaining availability information of reference blocks of a current image block, and determining whether the reference blocks are available according to the availability information, where the reference blocks of the current image block include a left side block, an upper side block, and an upper left block of the current image block; if at least one of the reference blocks is available, and at least one is unavailable, filling a pixel value in the available reference block to the unavailable reference block as a reference pixel value of the current image block; and predicting the current image block according to the reference pixel value.
    Type: Application
    Filed: July 12, 2013
    Publication date: November 14, 2013
    Inventors: Yongbing LIN, Changcai Lai
  • Publication number: 20130301722
    Abstract: The present invention discloses a method for coding an image, a method for decoding an image, a method for processing image data, and devices thereof. The method for coding the image includes: determining a current intra coding block that uses a constrained intra prediction method among current inter coded frames; determining that neighboring coding blocks that are adjacent to the current intra coding block include a neighboring inter coding block; updating image data in the neighboring inter coding block based on an invariable value or image data in a neighboring intra coding block included in the neighboring coding blocks; and coding the current intra coding block based on the updated image data in the neighboring inter coding block. By using the methods and devices, the error recovery capability of an intra coding block may be improved, and the image data decoding quality may be improved.
    Type: Application
    Filed: July 10, 2013
    Publication date: November 14, 2013
    Inventors: Changcai LAI, Yongbing Lin, Xiaozhen Zheng
  • Publication number: 20130301707
    Abstract: An encoding method with multiple image block division manners is disclosed, including: determining a division manner and a division direction of an image block; dividing the image block to obtain image subblocks sequentially arranged horizontally or vertically; determining whether the image subblocks need subdivision, and if subdivision is not needed, predicting the encoding object in the frame according to the image subblocks, to obtain residual data; performing transformation, quantization, and entropy encoding for the residual data so as to obtain coded residual data; and writing the division manner of the image block, the division direction of the image block, an identifier indicating whether the image subblocks need subdivision, and the coded residual data into a bitstream. By applying the encoding method, better prediction accuracy can be achieved when the image block presents a small change of pixel value in the horizontal or vertical direction.
    Type: Application
    Filed: July 10, 2013
    Publication date: November 14, 2013
    Inventors: Changcai LAI, Xiaoran CAO, Yongbing LIN, Lingzhi LIU, Yun HE
  • Publication number: 20130301730
    Abstract: In embodiments of the present invention, a first reference point and a second reference point that correspond to a prediction point are obtained from an upper reference edge and a left reference edge of a prediction block respectively according to a position of the prediction point in the prediction block and a prediction texture direction that corresponds to a prediction mode. Then linear interpolation is performed, according to the position of the prediction point, on the first reference point and the second reference point to obtain a predicted value of the prediction point.
    Type: Application
    Filed: July 15, 2013
    Publication date: November 14, 2013
    Inventors: Yongbing Lin, Changcai Lai
  • Publication number: 20130003832
    Abstract: A method comprising receiving a plurality of reference pixels, computing a plurality of filter coefficients based on differences between a reference pixel and neighboring reference pixels in the plurality of reference pixels, and combining the filter coefficients with the reference pixel and the neighboring reference pixels to generate a filtered value, wherein the filtered value is used for intra prediction.
    Type: Application
    Filed: June 13, 2012
    Publication date: January 3, 2013
    Applicant: FUTUREWEI TECHNOLOGIES, INC.
    Inventors: Guichun Li, Lingzhi Liu, Changcai Lai, Nam Ling, Jianhua Zheng, Philipp Zhang
  • Publication number: 20120320974
    Abstract: An apparatus comprising a processor configured to determine whether to use an intra smoothing filter for a rectangular prediction unit (PU) based on a lookup table (LUT) used for square PUs, wherein a width of the rectangular PU is not equal to a height of the rectangular PU.
    Type: Application
    Filed: May 18, 2012
    Publication date: December 20, 2012
    Applicant: FUTUREWEI TECHNOLOGIES, INC.
    Inventors: Guichun Li, Lingzhi Liu, Changcai Lai, Nam Ling, Jianhua Zheng, Philipp Zhang