公开(公告)号：US10750169B2

公开(公告)日：2020-08-18

申请号：US16338511

申请日：2017-09-29

Applicant: MEDIATEK INC.

Inventor： Jungsun Kim ,  Xiaozhong Xu ,  Shan Liu

IPC: H04N19/11 ,  H04N19/186 ,  H04N19/159

Abstract: A method and apparatus for chroma Intra prediction are disclosed. According to one method, a chroma Intra mode set comprising more than six chroma Intra coding modes are generated and chroma Intra-prediction encoding or decoding is applied to the current chroma block using a current chroma Intra mode selected from the chroma Intra mode set. According to another method, a chroma MPM list is determined and a current chroma Intra mode is signaled using chroma MPM process at the video encoding system or parsing the current chroma Intra mode using the chroma MPM process at the video decoding system, where the chroma MPM process comprises using a chroma MPM flag to indicate whether the current chroma Intra mode belongs to the chroma MPM list.

公开(公告)号：US10375371B2

公开(公告)日：2019-08-06

申请号：US15647630

申请日：2017-07-12

Applicant: MediaTek Inc.

Inventor： Xiaozhong Xu ,  Shan Liu

IPC: H04N7/12 ,  H04N11/02 ,  H04N11/04 ,  H04N13/106 ,  H04N13/161 ,  H04N19/117 ,  H04N19/167 ,  H04N19/46 ,  H04N19/86 ,  G06T3/00 ,  H04N19/136 ,  H04N19/182 ,  H04N19/423

Abstract: A video system for encoding or decoding 360-degree virtual reality (360VR) video is provided. The system performs filtering operations to reduce coding artifacts and discontinuities in a projection image of an omnidirectional image. The video system identifies first and second edges of the projection image. The first and second edges are physically correlated as a common edge in the omnidirectional image but not physically connected in the projection image. The system computes a set of filtered pixels based on a first set of pixels near the first edge and a second set of pixels near the second edge.

公开(公告)号：US10205968B2

公开(公告)日：2019-02-12

申请号：US15545381

申请日：2016-02-03

Applicant: MEDIATEK INC.

Inventor： Shan Liu ,  Xiaozhong Xu ,  Tzu-Der Chuang ,  Yu-Chen Sun ,  Wang-Lin Lai ,  Yu-Wen Huang ,  Jing Ye

IPC: H04N19/93 ,  H04N19/593 ,  H04N19/70 ,  H04N19/182

Abstract: A method of palette index map coding of blocks in a picture by grouping coded symbols of the same type is disclosed for video encoder and decoder. In one embodiment, all syntax elements corresponding to the pixel index are grouped into a pixel index group, and all syntax elements corresponding to the escape pixel are grouped into an escape pixel group. All syntax elements corresponding to the run type and run length are grouped into an interleaved run type/run length group, or grouped into separate run type group and run length group. In another embodiment, the system parses from the video bitstream a last-run mode syntax element for a current block, where the last-run mode syntax element indicates whether a last run mode is a copy-index mode or a copy-above mode. Information associated with the last-run mode syntax element is used for reconstructing palette index map.

公开(公告)号：US10171834B2

公开(公告)日：2019-01-01

申请号：US15031878

申请日：2014-12-01

Applicant: MEDIATEK INC.

Inventor： Shan Liu ,  Xiaozhong Xu ,  Karen Yun Chang

IPC: H04N11/02 ,  H04N19/593 ,  H04N19/139 ,  H04N19/176 ,  H04N19/11 ,  H04N19/583 ,  H04N19/182 ,  H04N19/172

Abstract: Implementations of techniques of intra picture block copy in video compression are described. In one example implementation, a method may include: identifying a first block of pixels of a plurality of pixels of a picture as a reference block for reconstructing a second block of pixels of the plurality of pixels of the picture; determining an overlapped region of the second block that overlaps with the first block; and reconstructing pixels in the overlapped region based on a first set of pixels and a second set of pixels of the first block.

公开(公告)号：US20180109810A1

公开(公告)日：2018-04-19

申请号：US15730842

申请日：2017-10-12

Applicant: MEDIATEK INC.

Inventor： Xiaozhong Xu ,  Shan Liu

IPC: H04N19/62 ,  H04N19/52 ,  H04N19/573 ,  H04N19/176

CPC classification number: H04N19/62 ,  H04N19/105 ,  H04N19/11 ,  H04N19/17 ,  H04N19/176 ,  H04N19/52 ,  H04N19/573 ,  H04N19/597

Abstract: Methods and apparatus for coding a 360-degree VR image sequence are disclosed. According to one method, input data associated with a current image in the 360-degree VR image sequence are received and also a target reference picture associated with the current image is received. An alternative reference picture is then generated by extending pixels from spherical neighboring pixels of one or more boundaries related to the target reference picture. A list of reference pictures including the alternative reference picture is provided for encoding or decoding the current image. The process of extending the pixels may comprise directly copying one pixel region, padding the pixels with one rotated pixel region, padding pixels with one mirrored pixel region, or a combination thereof.

公开(公告)号：US20170272744A1

公开(公告)日：2017-09-21

申请号：US15460835

申请日：2017-03-16

Applicant: MEDIATEK INC.

Inventor： Shan LIU ,  Xiaozhong Xu

IPC: H04N19/105 ,  H04N19/51 ,  H04N19/70 ,  H04N19/15

CPC classification number: H04N19/105 ,  H04N19/15 ,  H04N19/172 ,  H04N19/176 ,  H04N19/184 ,  H04N19/51 ,  H04N19/573 ,  H04N19/577 ,  H04N19/70

Abstract: Aspects of the disclosure provide an apparatus for encoding a sequence of pictures into a coded bit stream. The apparatus can include a decoded picture buffer (DPB) configured to store reference pictures, at least one of the reference pictures being an interpolated reference picture (IRP), an interpolation circuit configured to generate the IRP based on the reference pictures stored in the DPB, an encoding circuit configured to encode a current picture in the sequence of pictures based on a value of a variable indicating whether the current picture is to be encoded using the IRP, and an encoding controller configured to determine the value of the variable according to a size of DPB and the reference pictures stored in the DPB.

公开(公告)号：US12289456B2

公开(公告)日：2025-04-29

申请号：US16338514

申请日：2017-09-28

Applicant: MEDIATEK INC.

Inventor： Jing Ye ,  Xiaozhong Xu ,  Shan Liu

IPC: H04N19/176 ,  H04N19/105 ,  H04N19/11 ,  H04N19/159 ,  H04N19/186 ,  H04N19/593

Abstract: A method and apparatus for video coding of chroma coded in derived-mode Intra prediction are disclosed. If derived-mode (DM) Intra prediction is selected for a current chroma block, a corresponding luma block area is determined by locating a first upper-left pixel address of the corresponding luma block area corresponding to that of the current chroma block. Further, one or more candidate luma coding modes are determined from a sub-block set consisting of one or more sub-blocks of the corresponding luma block area, where if the sub-block set consists of only one sub-block, the sub-block set excludes a corner sub-block located at a top-left corner of the corresponding luma block area. Additionally, a current chroma Intra mode for the current chroma block is derived based on information comprising the candidate luma coding modes, and Intra-prediction encoding or decoding is applied to the current chroma block using the current chroma Intra mode derived.

公开(公告)号：US11375226B2

公开(公告)日：2022-06-28

申请号：US16827881

申请日：2020-03-24

Applicant: MEDIATEK INC.

Inventor： Tzu-Der Chuang ,  Ching-Yeh Chen ,  Han Huang ,  Xiaozhong Xu ,  Shan Liu

IPC: H04N19/513 ,  H04N19/423 ,  H04N19/52 ,  H04N19/537 ,  H04N19/119 ,  H04N19/176 ,  H04N19/58 ,  H04N19/105

Abstract: An embodiment of the method receives input data associated with a current block in a current picture at a video encoder or receiving a video bitstream corresponding to compressed data including the current block in the current picture at a video decoder, wherein the current block is coded or to be coded in an affine mode according to an affine motion model; calculates and storing affine parameters for a plurality of coded blocks in the current picture; retrieves the affine parameters of one or more coded blocks from the temporal buffer; derives an affine candidate including affine motion vectors using the retrieved affine parameters of the neighboring block; and encodes or decodes the current block by predicting the current block using one or more motion compensated blocks by the derived affine candidate.

公开(公告)号：US11146794B2

公开(公告)日：2021-10-12

申请号：US15746892

申请日：2016-07-26

Applicant: MEDIATEK INC.

Inventor： Shan Liu ,  Xiaozhong Xu

IPC: H04N19/159 ,  H04N19/105 ,  H04N19/172 ,  H04N19/174 ,  H04N19/176 ,  H04N19/186 ,  H04N19/52 ,  H04N19/70 ,  H04N19/82

Abstract: A method and system for video system using coding modes including an Inter prediction mode and an Intra Block Copy (IntraBC) mode are disclosed. A syntax element in a bitstream is determined to indicate whether two versions of a reconstructed current image unit are needed. If two versions of the reconstructed current image unit are needed, a loop-filtered version of the reconstructed current image unit and a non-loop-filter version of the reconstructed current image unit are allowed to be stored and used as reference data. Otherwise, only one version of the reconstructed current image unit is stored as the reference data. According to another method, bi-prediction mode is converted to uni-prediction mode for a certain prediction mode, where the bandwidth exceeds the existing worst case.

公开(公告)号：US11122276B2

公开(公告)日：2021-09-14

申请号：US16581077

申请日：2019-09-24

Applicant: MEDIATEK INC.

Inventor： Xiaozhong Xu ,  Shan Liu

IPC: H04N19/159 ,  H04N19/134 ,  H04N19/152 ,  H04N19/423 ,  H04N19/172 ,  H04N19/82 ,  H04N19/70 ,  H04N19/105 ,  H04N19/58 ,  H04N19/174

Abstract: A method for a video encoder or decoder using an Intra Block Copy (IntraBC) mode is disclosed. If IntraBC mode is enabled and no loop filter is used for a current picture, a currently decoded reference picture for the current picture is marked as a long-term reference picture before and during decoding of the current picture. The currently decoded reference picture is assigned in reference picture list construction for IntraBC reference of the current picture and buffer fullness for the DPB is calculated before starting decoding the current picture by taking into account of only one reference picture buffer. According to another method, if the maximum DPB size is 1, a variable or a syntax element is set to a target value to impose restriction to use only one picture storage buffer in the DPB to store reference picture for encoding or decoding of a current picture.