Lg Electronics Inc.

Guangdong Oppo Mobile Telecommunications Corp., Ltd.

Beijing Xiaomi Mobile Software Co., Ltd.

Vivo Mobile Communication Co., Ltd.

Xiaomi Inc.

Rosedale Dynamics LLC

Taissa Research LLC

Junghak Nam

Hyeongmoon Jang

Naeri Park

Jaehyun Lim

Seunghwan Kim

Jin Seong Heo

Sunmi Yoo Yoo

Moonmo Koo

Jangwon Choi

Jungdong Seo

Jaeho Lee

Jungah Choi

Ling Li

Sehoon Yea

Eunyong Son

Chulkeun Kim

Hendry Hendry

Yongjoon Jeon

Seungwook Park

Mehdi Salehifar

Taesup Kim

Seethal Paluri

Jie Zhao

Bumshik Lee

Kyuwoon Kim

An image decoding method according to the present document comprises a step of deriving POC values for the current picture and reference pictures on the basis of POC information, wherein the POC information includes a maximum LSB value of POC, information about the reference pictures includes a non-reference picture flag related to whether a picture is not used as a reference picture, the value of the non-reference picture flag of the previous picture used for deriving the POC value of the current picture is zero, and the difference between the POC values of the current picture and the previous picture is less than half of the maximum LSB value of POC.

Image coding method and device therefor

An image decoding method performed by a decoding device according to the present document comprises the steps of: deriving a motion vector for a current block; determining whether to apply refinement to the motion vector for the current block; deriving a refined motion vector by applying decoder-side motion vector refinement (DMVR) to the motion vector if it is determined to apply refinement to the motion vector for the current block; deriving prediction samples for the current block on the basis of the refined motion vector; and generating reconstruction samples for the current block on the basis of the prediction samples, wherein the step of determining whether to apply refinement includes determining whether to apply the refinement on the basis of at least one of the size of the current block and bi-prediction weight index information for the current block.

DMVR-based inter-prediction method and device

An image decoding method performed by a decoding device according to the present document comprises the steps of: acquiring a block-based delta pulse code modulation (BDPCM) flag for a current block; on the basis of the BDPCM flag indicating that BDPCM is applied to the current block, acquiring a BDPCM direction flag for the current block; and storing, as an intra-prediction mode of the current block, an intra-prediction mode of a prediction direction derived on the basis of the BDPCM direction flag.

Image decoding method and device thereof

An image decoding method performed by a decoding device according to the present disclosure comprises the steps of: receiving a bitstream including prediction information for a current block; deriving a chroma array type for the current block on the basis of a separate color plane flag indicating whether three color components are separately coded and a chroma format index indicating a chroma format sampling structure for the current block, which are included in the prediction information for the current block; deriving prediction samples for the current block on the basis of the derived chroma array type; and deriving reconstructed samples for the current block on the basis of the prediction samples.

Method and device for signaling information on chroma format

An image decoding method performed by a decoding device according to the present disclosure comprises the steps of: deriving neighboring samples for sign prediction of a current block; deriving costs of sign combination candidates for transform coefficients of the current block on the basis of the neighboring samples; predicting signs of the transform coefficients from the sign combination candidates on the basis of the costs; deriving residual samples of the current block on the basis of the predicted signs; and generating a reconstructed picture on the basis of the residual samples.

Image decoding method and device

According to one embodiment of the present document, an in-loop filtering procedure in an image/video coding procedure may include a cross-component adaptive loop filtering procedure. CCALF according to the present embodiment can increase the accuracy of in-loop filtering.

Cross-component adaptive loop filtering-based image coding apparatus and method

A method by which a decoding device decodes an image, according to the present document, comprises the steps of: acquiring prediction-related information about the current block; acquiring residual information about the current block; deriving a prediction sample of the current block on the basis of the prediction-related information; deriving a residual sample of the current block on the basis of the residual information; and generating a reconstructed picture on the basis of the prediction sample and the residual sample.

Image decoding method for coding image information including TSRC available flag, and device 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

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

According to one embodiment of the present document, filtering for chroma blocks can be performed on the basis of luma blocks. For example, a cross component adaptive loop filtering process can be performed. Therefore, the accuracy of in-loop filtering can be improved.

Adaptive loop filtering-based image coding apparatus and method

In the present invention, a method for processing an image on the basis of an intra prediction mode and an apparatus therefor are disclosed. Particularly, the method for processing an image on the basis of an intra prediction mode may comprise the steps of: partitioning a block to be processed, on the basis of an intra prediction mode of the block to be processed; and performing intra prediction for the split block to be processed, wherein the direction in which the block to be processed is split is perpendicular to the prediction direction of the intra prediction mode of the block to be processed.

Method for processing image on basis of intra prediction mode and apparatus 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

An image decoding method carried out by a decoding device, according to the present document, comprises the steps of: acquiring a sign data hiding enable flag; acquiring a transform skip residual coding (TSRC) enable flag on the basis of the sign data hiding enable flag; acquiring residual information for a current block, on the basis of the TSRC enable flag; deriving a residual sample of the current block, on the basis of the residual information; and generating a reconstructed picture on the basis of the residual sample, wherein the sign data hiding enable flag is a flag indicating whether sign data hiding is enabled, the TSRC enable flag is a flag indicating whether TSRC is enabled, and the TSRC enable flag is acquired on the basis of the sign data hiding enable flag having a value of zero.

Image decoding method for residual coding, and device therefor

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 document comprises a step for performing inverse first-order transform and inverse non-separable transform on a residual sample. The inverse non-separable transform is performed on the basis of a transform index indicating a predetermined transform kernel matrix, the inverse first-order transform is performed on the basis of a multiple transform selection (MTS) index indicating MTS for a horizontal transform kernel and a vertical transform kernel, and a syntax element bin string for the transform index is derived on the basis of first context information when a tree type for a split structure of a target block is not a single tree type and is derived on the basis of second context information when the tree type is the single tree type.

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Seoul, South Korea

Junghak Nam