Lg Electronics Inc.

Rosedale Dynamics LLC

Beijing Xiaomi Mobile Software Co., Ltd.

Taissa Research LLC

Naeri Park

Junghak Nam

Hyeongmoon Jang

Jaehyun Lim

Chulkeun Kim

Joonyoung Park

Yongjoon Jeon

Seungwook Park

Hendry Hendry

Byeongmoon Jeon

Jungsun Kim

Seunghwan Kim

Jungdong Seo

Jaeho Lee

Ling Li

Sunmi Yoo Yoo

Sangoh Jeong

Sang Oh Jeong

Jin Seong Heo

Seethal Paluri

Hyunsoo Kim

Kyuwoon Kim

Jinseok Im

Sungho Bae

Seoungwook Park

Cheoljoo Lee

Jaewon Ha

Beyongmoon Jeon

A deblocking filtering method, a boundary strength (bS) deriving method, and encoding/decoding method and apparatus using the methods are provided. The bS deriving method includes the steps of: deriving a boundary of a deblocking filtering unit block which is a unit block on which deblocking filtering is performed; and setting a bS for each bS setting unit block in the deblocking filtering unit block. Here, the step of setting the bS includes setting a bS value of a target boundary corresponding to the boundary of the deblocking filtering unit block as the bS setting unit block.

Method and apparatus for encoding/decoding image information

An inter predication method is provided. The method includes: generating a merging candidate list of a block to be predicted and corresponding to a current prediction unit (PU); deriving motion information of the block to be predicted, on the basis of one of a plurality of merging candidates constituting the merging candidate list; and performing a prediction on the block to be predicted, on the basis of the derived motion information, to generate a prediction block corresponding to the current PU.

Inter prediction method and apparatus therefor

An image decoding method according to the present document comprises: decoding a current block on the basis of image information, wherein an MVP candidate list for the current block is derived on the basis of an inter prediction mode, which is derived on the basis of image information, and peripheral blocks of the current block; and deriving motion information of the current block on the basis of the MVP candidate list, wherein the peripheral blocks include a left bottom corner peripheral block, a left peripheral block, a right top corner peripheral block, a top peripheral block, and a left top corner peripheral block of the current block, the motion information includes an L0 motion vector for L0 prediction and/or an L1 motion vector for L1 prediction, the L0 motion vector is derived on the basis of an L0 motion vector predictor and an L0 motion vector difference, and the L1 motion vector is derived on the basis of an L1 motion vector predictor and an L1 motion vector difference.

Motion vector prediction-based image/video coding method and device

A decoding apparatus includes at least one processor configured to acquire image information including inter prediction mode information and residual information through a bitstream; generate residual samples based on the residual information; generate prediction samples of a current block by applying a prediction mode determined based on the inter prediction mode information; and generate reconstructed samples based on the prediction samples and the residual samples. The inter prediction mode information includes at least one of a first flag related to whether a subblock merge mode is applied, a second flag related to whether a regular merge mode is applied, a third flag related to whether a merge mode with motion vector difference (MMVD) is applied or a fourth flag related to whether a combined inter-picture merge and intra-picture prediction (CIIP) mode is applied.

Image decoding method comprising generating prediction samples by applying determined prediction mode, and device therefor

According to the disclosure of the present document, when the inter-prediction type of the current block indicates biprediction, weight index information for a candidate in a merge candidate list or sub-block merge candidate list can be derived, and coding efficiency can be raised.

Image decoding method for deriving weight index information for biprediction, and device for same

According to embodiments of the present document, information for performing in-loop filtering across boundaries can be efficiently signaled. For example, the boundaries may include boundaries of tiles, slices, and/or sub-pictures.

In-loop filtering-based image coding device and method

An image decoding method according to the present invention comprises the steps of: acquiring information to form a reference picture set of a current picture by entropy decoding the received bitstream information; and performing prediction on a prediction block inside the current picture by using a reference picture list which is formed based on the reference picture set.

Method and device for transmitting image information, and decoding method and device using same

According to embodiments of the present document, a prediction procedure may be performed for image/video coding, and the prediction procedure may include symmetric motion vector differences (SMVDs) and merge mode motion vector differences (MMVDs) according to an inter prediction. The inter prediction may be performed on the basis of reference pictures of a current picture, and types (e.g., a long term reference picture, a short term reference picture, etc.) of the reference pictures may be considered for the inter prediction. Therefore, performance and coding efficiency in the prediction procedure can be improved.

Method and device for image coding using motion vector differences

A decoding method performed by a decoding device according to the present document comprises the steps of determining a prediction mode of a current block on the basis of information about a prediction mode obtained from a bitstream; constructing a merge candidate list on the basis of the prediction mode; deriving motion information of the current block on the basis of the merge candidate list; and generating prediction samples of the current block on the basis of the motion information, wherein the bitstream includes information about a combined inter-picture merge and intra-picture prediction (CIIP) available flag indicating whether the CIIP is available, and the determination step may include a step of acquiring a regular merge flag from the bitstream on the basis of the CIIP available flag.

Method and device for removing redundant syntax from merge data syntax

An image decoding method comprises the steps of: determining whether or not an application condition of decoder-side motion vector refinement (DMVR) for applying motion vector refinement for a current block is satisfied; deriving a minimum sum of absolute differences (SAD) on the basis of L0 and L1 motion vectors of the current block if the application condition of the DMVR is satisfied; deriving refined L0 and L1 motion vectors of the current block based on the minimum SAD; deriving prediction samples of the current block based on the refined L0 and L1 motion vectors; and generating reconstructed samples of the current block based on the prediction samples. With respect to whether or not the application condition of the DMVR is satisfied, the application condition of the DMVR is determined to be satisfied if a prediction mode, in which inter-prediction and intra-prediction are combined, is not applied to the current block.

DMVR-based inter-prediction method and device

An image decoding method according to the present document is characterized in that: decoder-side motion vector refinement (DMVR) is applied to derive refined L0 and L1 motion vectors on the basis of L0 and L1 motion vectors of the current block; prediction samples of the current block are derived on the basis of L0 prediction samples derived on the basis of the refined L0 motion vector and L1 prediction samples derived on the basis of the refined L1 motion vector; and recovery samples of the current block are generated on the basis of the prediction samples, wherein the L0 prediction samples are derived on the basis of an L0 reference picture and the refined L0 motion vector, the L1 prediction samples are derived on the basis of an L1 reference picture and the refined L1 motion vector, and in the step for deriving the prediction samples, whether to apply a bi-directional optical flow (BDOF) process is determined on the basis of whether a first POC difference between the current picture and the L0 reference picture and a second POC difference between the current picture and the L1 reference picture are the same.

Inter-prediction method and device based on DMVR and BDOF

According to the disclosure of the present document, in a subblock-based temporal motion vector prediction (sbTMVP), a position of a subblock for deriving a motion vector per subblock unit can be efficiently calculated, and thus video/image coding efficiency can be increased and hardware implementation can be simplified.

Inter-prediction-based image or video coding using sbTMVP

According to the disclosure of the present document, weight index information for sub-block merge candidates of a current block can be derived and coding efficiency can be increased.

Image decoding method and device therefor

According to embodiments according to the present document, merge mode motion vector differences (MMVD) and symmetric motion vector differences (SMVD) may be performed on the basis of reference picture types and, in particular, short-term reference pictures may be used. Accordingly, prediction performance and coding efficiency in an inter prediction mode may be increased.

Image encoding/decoding method and a transmission method using motion vector

A method for image decoding, according to the present invention, includes the following steps: receiving image information including a plurality of filter coefficients; generating a restored block for a current block on the basis of the image information; and applying an adaptive loop filter to the restored block on the basis of the plurality of filter coefficients. According to the present invention, image encoding efficiency may be improved, and complexity may be reduced.

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Seoul, South Korea

Naeri Park