Lg Electronics Inc.

Guangdong Oppo Mobile Telecommunications Corp., Ltd.

Beijing Xiaomi Mobile Software Co., Ltd.

Vivo Mobile Communication Co., Ltd.

Rosedale Dynamics LLC

Tcl King Electrical Appliances (huizhou) Co. Ltd.

Taissa Research LLC

Hyeongmoon Jang

Junghak Nam

Naeri Park

Jaehyun Lim

Seunghwan Kim

Moonmo Koo

Jaeho Lee

Seungwook Park

Jin Seong Heo

Yongjoon Jeon

Eunyong Son

Jungdong Seo

Hendry Hendry

Sunmi Yoo Yoo

Ling Li

Jie Zhao

Sehoon Yea

Bumshik Lee

Seethal Paluri

Mehdi Salehifar

A video decoding method performed by a decoding device according to the present document is characterized by including: a step for deriving reference subblocks in a reference picture on the basis of the motion vector of an adjacent block on the left side of the current block; a step for deriving a subblock-based temporal merge candidate for the current block on the basis of motion information about the reference subblocks; a step for forming an affine merge candidate list for the current block, the affine merge candidate list including the subblock-based temporal merge candidate; a step for deriving motion information about subblocks of the current block on the basis of the affine merge candidate list; a step for deriving prediction samples for the current block on the basis of the motion information about the subblocks; and a step for generating a reconstructed picture on the basis of the prediction samples.

Affine motion prediction-based video decoding method and device using subblock-based temporal merge candidate in video coding system

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

According to the disclosure of the present document, image information acquired via a bitstream includes POC information, and a non-reference picture flag related to whether a picture is not used as a reference picture. A POC value of a current picture is derived on the basis of the POC information, and the POC information includes POC information of a previous picture in decoding order for the current picture. The previous picture in the decoding order for deriving the POC value of the current picture may be limited to a picture where a value of the non-reference picture flag is 0. Accordingly, an incorrect POC value can be prevented from being derived in video/image coding.

Image coding method based on POC information and non-reference picture flag in video or image coding system

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

Disclosed are a method for encoding a video signal and a device therefor. Specifically, a method for decoding an image based on an inter prediction mode comprises: generating a merging candidate list by using a spatial merge candidate and a temporal merge candidate of a current block; obtaining a merge index indicating a certain merge candidate in the merging candidate list; and generating a prediction block of the current block by using motion information of the certain merge candidate, wherein the generating of the merging candidate list may include adding a first merge candidate indicating a collocated block specified by motion information of the spatial merge candidate to the merging candidate list if a reference picture of the spatial merge candidate is same as a predetermined picture.

Inter-prediction mode-based image processing method and device therefor

An image decoding method according to the present document may comprise the steps of: receiving image information including residual information and an LFNST index from a bitstream; deriving a transform coefficient on the basis of the residual information; deriving a flag variable related to whether LFNST is applied to a current block on the basis of the LFNST index; and performing the LFNST on the basis of the flag variable and the transform coefficient, wherein the flag variable is derived for each color component of the current block.

Image coding method and device therefor

A video decoding method performed by a decoding apparatus includes the steps of: deriving control points (CP) for a current block; acquiring movement vectors for the CPs; deriving a sample unit movement vector in the current block on the basis of the acquired movement vectors; and deriving a prediction sample for the current block on the basis of the sample unit movement vector. According to the present invention, it is possible to effectively perform, through sample unit motion vectors, inter-prediction not only in a case where an image in the current block is plane-shifted but also in a case where there are various image distortions.

Inter prediction method and apparatus in video coding system

A method by which a decoding device decodes an image, according to the present document, comprises the steps of: receiving prediction mode information about a current block; receiving intra sub-partitions (ISP)-related information about the current block on the basis of the size and the maximum conversion block size of the current block; deriving an intra prediction mode of the current block on the basis of the prediction mode information; and generating a prediction sample of the current block on the basis of the intra prediction mode and the ISP-related information.

Intra prediction method and device based on intra sub-partitions in image coding system

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

Provided is an image decoding method performed by a decoding apparatus including deriving a temporary reference motion vector for a current block included in a current picture, deriving a reference motion vector for the current block by applying clipping to the temporary reference motion vector, deriving a motion vector for the current block based on the reference motion vector, deriving a predicted block for the current block based on the motion vector for the current block, and generating a reconstructed picture for the current picture based on the predicted block for the current block, wherein a number of bits of a binary code representing the reference motion vector is less than a number of bits of a binary code representing the temporary reference motion vector.

Method and apparatus for deriving motion vector

The present invention discloses an image coding/decoding method and an apparatus for the method. More specifically, a method for filtering an image by a decoding apparatus comprises deriving boundaries of a block divided into quad-tree plus binary-tree structure; determining an edge among boundaries of the block to which de-blocking filtering is applied; determining a type of de-blocking filtering to be applied to the edge; and performing de-blocking filtering to a picture sample restored according to the de-blocking filtering type, wherein the edge or the type of de-blocking filtering is determined by considering width or height of the block.

Image coding/decoding method and apparatus therefor

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

A method for decoding an image, according to the present document, comprises: receiving a bitstream including BDPCM information; deriving residual samples for a current block on the basis of the BDPCM information; deriving prediction samples for the current block on the basis of the BDPCM information; generating a reconstructed picture on the basis of the residual samples and the prediction samples; and performing deblocking filtering on the reconstructed picture, wherein when BDPCM is applied to the current block, the deblocking filtering is not performed.

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Seoul, South Korea

Hyeongmoon Jang