Modified transform-based image coding method and device for same

    公开(公告)号:US11700377B2

    公开(公告)日:2023-07-11

    申请号:US17535095

    申请日:2021-11-24

    CPC classification number: H04N19/132 H04N19/176 H04N19/18 H04N19/186

    Abstract: An image decoding method according to the present document is characterized by including: a step for receiving a bitstream including residual information; a step for deriving transform coefficients for a target block on the basis of the residual information; a step for deriving corrected transform coefficients on the basis of an inverse non-separable transform of the transform coefficients; and a step for deriving residual samples for the target block on the basis of an inverse primary transform of the corrected transform coefficients, wherein the inverse non-separable transform is performed when the size of the target block is equal to or smaller than the size of a prescribed maximum transform application block.

    Inter prediction method and apparatus based on history-based motion vector

    公开(公告)号:US11632564B2

    公开(公告)日:2023-04-18

    申请号:US17065822

    申请日:2020-10-08

    Abstract: An image decoding method according to the present disclosure includes deriving a history-based motion vector prediction (HMVP) buffer for a current block, deriving motion information of the current block based on an HMVP candidate included in the HMVP buffer, generating prediction samples for the current block based on the motion information, and generating reconstructed samples based on the prediction samples, and the HMVP buffer is initialized when processing a first-ordered CTU in a CTU row in which a current CTU is located, and the current block is included in the current CTU.

    IMAGE DECODING METHOD FOR DERIVING PREDICTED SAMPLE BY USING MERGE CANDIDATE AND DEVICE THEREFOR

    公开(公告)号:US20230077012A1

    公开(公告)日:2023-03-09

    申请号:US17979403

    申请日:2022-11-02

    Abstract: The present invention relates to a method for encoding and decoding images, wherein, if bi-prediction is applied, a weight for a merge candidate is derived, thereby improving the image compression efficiency, and making it possible to efficiently configure a motion vector candidate. A merge candidate list of the current block is produced on the basis of inter-prediction information, and the candidate includes a configured affine merge candidate. If the configured affine merge candidate is produced on the basis of a combination of control points including CP0, weight index information regarding the configured affine merge candidate is produced on the basis of weight index information regarding CP0. If the configured affine merge candidate is produced on the basis of a combination of control points excluding CP0, weight index information regarding the configured affine merge candidate is derived on the basis of weight index information regarding CP1.

    Image decoding method using BDPCM and device therefor

    公开(公告)号:US11595668B2

    公开(公告)日:2023-02-28

    申请号:US17612525

    申请日:2020-05-22

    Abstract: An image decoding method performed by a decoding apparatus according to the present document comprises the steps of: deriving prediction samples for a first sample and a second sample of the current block on the basis of BDPCM-related information about the current block and neighboring samples of the current block; deriving residual samples for the first sample and the second sample on the basis of a residual coefficient of the first sample and a modified residual coefficient of the second sample; and storing, as the intra prediction mode of the current block, the intra prediction mode in the prediction direction of the current block, which is derived on the basis of a BDPCM direction flag.

    Method for processing image and apparatus therefor

    公开(公告)号:US11589064B2

    公开(公告)日:2023-02-21

    申请号:US17060598

    申请日:2020-10-01

    Abstract: A video decoding method includes: when a current block satisfies a preconfigured condition, parsing a first syntax element indicating whether the current block is split into a plurality of sub-blocks; when the first syntax element indicates that the current block is split, parsing a second syntax element indicating whether the current block is split using a quad-tree structure; when the second syntax element indicates that the current block is not split using the quad-tree structure, parsing at least one of a third syntax element indicating whether the current block is split using a binary-tree structure or a ternary-tree structure and a fourth syntax element indicating a split direction of the current block; and determining a split mode of the current block based on at least one of the first syntax element, the second syntax element, the third syntax element and the fourth syntax element.

    Coding of information about transform kernel set

    公开(公告)号:US11570438B2

    公开(公告)日:2023-01-31

    申请号:US17556099

    申请日:2021-12-20

    Abstract: An image decoding method includes: acquiring a multiple transform selection (MTS) index and residual information from a bitstream; deriving transform coefficients for the current block on the basis of the residual information; and generating residual samples of the current block on the basis of the MTS index and the transform coefficients, wherein the MTS index indicates a transform kernel set to be applied to the current block among transform kernel set candidates, at least one bin among bins of a bin string of the MTS index is derived on the basis of context coding, the context coding is performed on the basis of values of increase and decrease in a context index pertaining to the MTS index, and a single value of increase and decrease in the context index can be used for the context coding of the first bin among the bins of the bin string.

    Image decoding method for deriving predicted sample by using merge candidate and device therefor

    公开(公告)号:US11539941B2

    公开(公告)日:2022-12-27

    申请号:US17561642

    申请日:2021-12-23

    Abstract: The present invention relates to a method for encoding and decoding images, wherein, if bi-prediction is applied, a weight for a merge candidate is derived, thereby improving the image compression efficiency, and making it possible to efficiently configure a motion vector candidate. A merge candidate list of the current block is produced on the basis of inter-prediction information, and the candidate includes a configured affine merge candidate. If the configured affine merge candidate is produced on the basis of a combination of control points including CP0, weight index information regarding the configured affine merge candidate is produced on the basis of weight index information regarding CP0. If the configured affine merge candidate is produced on the basis of a combination of control points excluding CP0, weight index information regarding the configured affine merge candidate is derived on the basis of weight index information regarding CP1.

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