公开(公告)号：US20200374545A1

公开(公告)日：2020-11-26

申请号：US16968295

申请日：2019-02-11

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Zhi-Yi LIN ,  Ching-Yeh CHEN ,  Tzu-Der CHUANG

IPC: H04N19/52 ,  H04N19/70 ,  H04N19/176

Abstract: Methods and apparatus for a video coding system with the current picture referencing (CPR) mode enabled are disclosed. According to one method, when the current reference picture is equal to the current picture, an integer motion vector flag is inferred to be true without signalling the integer or parsing the motion vector flag. In another method, when all motion vector differences for the current block are equal to zero, an integer motion vector flag is inferred to be true without signalling the integer or parsing the motion vector flag. In yet another method, when all reference pictures for the current block are equal to the current picture: the sub-block prediction coding mode is disabled; and the current block is encoded or decoded by disabling the sub-block prediction coding mode. Alternatively, derived motion vectors associated with sub-blocks for the current block can be converted into integer motion vectors.

公开(公告)号：US20250119572A1

公开(公告)日：2025-04-10

申请号：US18730921

申请日：2023-01-16

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Tzu-Der CHUANG ,  Ching-Yeh CHEN

IPC: H04N19/513 ,  H04N19/105 ,  H04N19/139 ,  H04N19/176

Abstract: A method for constraining multi-pass decoder-side motion vector refinement (MP-DMVR) is provided. A video coder receives data for a block of pixels to be encoded or decoded as a current block of a current picture of a video. A video coder receives a motion vector that references a block of pixels in a reference picture based on the received data. A video coder refines the motion vector in a plurality of refinement passes by examining pixels in the reference picture that are identified based on the refined motion vector. The refinement of the motion vector is constrained by a refinement range. The video coder encodes or decodes the current block by using the refined motion vector to produce prediction residuals or to reconstruct the current block.

公开(公告)号：US20220303529A1

公开(公告)日：2022-09-22

申请号：US17619812

申请日：2020-06-24

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Ching-Yeh CHEN ,  Tzu-Der CHUANG

IPC: H04N19/117 ,  H04N19/82 ,  H04N19/132 ,  H04N19/186 ,  H04N19/172

Abstract: Methods and apparatus for video coding are disclosed. According to one method, First ALF (Adaptive Loop Filter) processing is applied to the reconstructed chroma samples for a target reconstructed chroma sample to generate a first filtered chroma sample. Second ALF processing is applied to the related reconstructed luma samples to generate a second filtered chroma sample for the target reconstructed chroma sample, where positions of the related reconstructed luma samples selected for the second ALF processing are determined according to the target chroma format. According to another method, the luma ALF and the cross-component ALF have the same filter coefficient precision.

公开(公告)号：US20220094966A1

公开(公告)日：2022-03-24

申请号：US17545011

申请日：2021-12-08

Applicant: MEDIATEK INC.

Inventor： Tzu-Der CHUANG ,  Ching-Yeh CHEN ,  Chen-Yen LAI ,  Chih-Wei HSU

IPC: H04N19/513 ,  H04N19/105 ,  H04N19/119 ,  H04N19/159 ,  H04N19/176 ,  H04N19/533

Abstract: Video processing methods and apparatuses for coding a current block comprise receiving input data of a current block, partitioning the current block into multiple sub-blocks, deriving sub-block MVs for the current block according to a sub-block motion compensation coding tool, constraining the sub-block MVs to form constrained sub-block MVs, and encoding or decoding the current block using the constrained sub-block MVs, and applying motion compensation to the current block using the constrained sub-block MVs to encode or decode the current block. The sub-block MVs may be constrained according to a size, width, or height of the current block or a sub-block, an inter prediction direction of one of control point MVs of the current block, the current block, or current sub-block, the control point MVs, or a combination of the above.

公开(公告)号：US20220094919A1

公开(公告)日：2022-03-24

申请号：US17424656

申请日：2020-01-21

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Ching-Yeh CHEN ,  Tzu-Der CHUANG ,  Yu-Wen HUANG

IPC: H04N19/117 ,  H04N19/82 ,  H04N19/159

Abstract: Methods and apparatus for Adaptive Loop Filter (ALF) processing of reconstructed video are disclosed. According to one method, clipping values for the ALF processing are determined depending on a bit depth of a center reconstructed pixel. A current ALF output for the current block is derived, where the current ALF output comprises a weighted sum of clipped differences of original differences and each of the original differences is calculated between a first reconstructed pixel at a non-center filter location and the center reconstructed pixel, and each of the original differences is clipped according to a corresponding clipping value to form one clipped difference. In another method, a target clipping value is always signaled at an encoder side or parsed at a decoder side even if the target clipping value is zero. In another method, the clipping values are encoded or decoded using a fixed-length code.

公开(公告)号：US20210321106A1

公开(公告)日：2021-10-14

申请号：US17350966

申请日：2021-06-17

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Olena CHUBACH ,  Tzu-Der CHUANG ,  Ching-Yeh CHEN

IPC: H04N19/126 ,  H04N19/176 ,  H04N19/30 ,  H04N19/60 ,  H04N19/172

Abstract: A method and apparatus for video coding are disclosed. According to the present invention, a flag is determined, where the flag indicates whether a scaling matrix is enabled or not enabled for non-separable secondary transform (NSST) coded blocks. When the current block is one NSST coded block and the flag indicates that the scaling matrix is enabled for the NSST blocks, the scaling matrix is determined and applied to the current block. When the current block is one NSST coded block and the flag indicates that the scaling matrix is not enabled for the NSST coded blocks, the scaling matrix is skipped for the current block. According to another method, for a rectangular block, a target scaling matrix is generated directly from a square base scaling matrix in one step without up-sampling-and-down-sampling or down-sampling-and-up-sampling.

公开(公告)号：US20210314560A1

公开(公告)日：2021-10-07

申请号：US17291085

申请日：2019-11-06

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Yu-Ling HSIAO ,  Tzu-Der CHUANG ,  Ching-Yeh CHEN

IPC: H04N19/105 ,  H04N19/159 ,  H04N19/96 ,  H04N19/186 ,  H04N19/176

Abstract: Video processing methods comprise receiving input data of a current block in a current picture, constructing a candidate list for the current block by including one or more History-based Motion Vector Predictor (HMVP) candidates, selecting one candidate from the candidate list, locating a reference block according to motion information of the selected candidate, and encoding or decoding the current block by predicting the current block using the reference block. The one or more HMVP candidates are fetched from a normal HMVP table if the current block is to be processed by a normal inter prediction mode, and the one or more HMVP candidates are fetched form a Current Picture Referencing (CPR) HMVP table if the current block is to be processed by a CPR mode. The two HMVP tables are separately maintained and updated.

公开(公告)号：US20200304794A1

公开(公告)日：2020-09-24

申请号：US16825175

申请日：2020-03-20

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Olena CHUBACH ,  Tzu-Der CHUANG ,  Ching-Yeh CHEN

IPC: H04N19/126 ,  H04N19/176 ,  H04N19/172 ,  H04N19/60 ,  H04N19/30

Abstract: A method and apparatus for video coding are disclosed. According to the present invention, a flag is determined, where the flag indicates whether a scaling matrix is enabled or not enabled for non-separable secondary transform (NSST) coded blocks. When the current block is one NSST coded block and the flag indicates that the scaling matrix is enabled for the NSST blocks, the scaling matrix is determined and applied to the current block. When the current block is one NSST coded block and the flag indicates that the scaling matrix is not enabled for the NSST coded blocks, the scaling matrix is skipped for the current block. According to another method, for a rectangular block, a target scaling matrix is generated directly from a square base scaling matrix in one step without up-sampling-and-down-sampling or down-sampling-and-up-sampling.

公开(公告)号：US20180359486A1

公开(公告)日：2018-12-13

申请号：US16001599

申请日：2018-06-06

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Ching-Yeh CHEN ,  Yu-Wen HUANG

IPC: H04N19/56 ,  H04N19/105 ,  H04N19/36 ,  H04N19/132 ,  H04N19/88 ,  H04N19/186

CPC classification number: H04N19/56 ,  H04N19/105 ,  H04N19/132 ,  H04N19/186 ,  H04N19/36 ,  H04N19/88

Abstract: Aspects of the disclosure provide a method for forming patch groups. The method can include determining a list of K motion vectors (MVs) for each current patch to form a patch group that includes the respective current patch and K reference patches corresponding to the K MVs, wherein the current patches are included in a reconstructed picture. The list of K MVs of a first current patch that is one of the current patches is determined by performing a neighbor-based fast search (NBFS) process. The NBFS process can include selecting K MVs from lists of K MVs of at least one neighboring current patch of the first patch to form a first list of K MVs of the first current patch, and performing a first refinement process to obtain a second list of K MVs of the first current patch based on the first list of K MVs.

公开(公告)号：US20230232012A1

公开(公告)日：2023-07-20

申请号：US18064434

申请日：2022-12-12

Applicant: MEDIATEK INC.

Inventor： Chen-Yen LAI ,  Tzu-Der CHUANG ,  Ching-Yeh CHEN

IPC: H04N19/137 ,  H04N19/105 ,  H04N19/176

CPC classification number: H04N19/137 ,  H04N19/105 ,  H04N19/176

Abstract: Methods and apparatus for video coding using non-adjacent affine candidates are provided. According to this method, one or more neighboring MVs (motion vectors) are determined from one or more non-adjacent affine-coded neighbors of the current block. CPMVs (Control-Point Motion Vectors) are determined based on said one or more neighboring MVs, wherein if a target neighboring block associated with one target neighboring MV (Motion Vector) is outside an available region, a derived CPMV) is generated to replace the target neighboring MV. An affine merge list or an affine AMVP (Advanced Motion Vector Prediction) list having said one or more neighboring MVs as one non-adjacent affine candidate is generated, wherein said one non-adjacent affine candidate generates a non-adjacent affine predictor using motion information according to the CPMVs. The current block is encoded or decoded using a motion candidate selected from the affine merge list or the affine AMVP list.