Lg Electronics Inc.

Rosedale Dynamics LLC

Guangdong Oppo Mobile Telecommunications Corp., Ltd.

Vivo Mobile Communication Co., Ltd.

Xiaomi Inc.

Tcl King Electrical Appliances (huizhou) Co. Ltd.

Beijing Xiaomi Mobile Software Co., Ltd.

Jangwon Choi

Jin Seong Heo

Sunmi Yoo Yoo

Jungah Choi

Seunghwan Kim

Ling Li

Jaehyun Lim

Junghak Nam

Seung Hwan Kim

Jaeho Lee

Jungdong Seo

Hyeong Moon Jang

Jung Hak Nam

Summi Yoo

A method by which a decoding device decodes a video, according to the present document, can comprise the steps of: acquiring, from a bitstream, information that indicates the level value of a transform coefficient in a current block; deriving, on the basis of whether the number of context coded bins maximally usable for the transform coefficient is greater than or equal to a threshold value, a rice parameter for the information that indicates the level value of the transform coefficient; deriving, on the basis of the rice parameter, a bin string for the information that indicates the level value of the transform coefficient; and deriving the level value of the transform coefficient on the basis of the bin string.

Entropy coding method and device in video/image coding system

An image decoding method performed by a decoding device according to the present document is characterized by comprising the steps of: acquiring image information including a Block-based Delta Pulse Code Modulation (BDPCM) available flag; and generating a reconstructed picture on the basis of the image information, wherein the BDPCM available flag relates to whether BDPCM is available for chroma and luma blocks.

Image decoding method and device for same

An image decoding method includes obtaining image information including prediction mode information from a bitstream, obtaining matrix-based intra prediction (MIP) flag information related to whether an MIP is applied to a current block based on the prediction mode information, deriving an MIP mode for the current block based on the MIP flag information, deriving an MIP matrix for the current block based on the MIP mode, generating MIP samples for the current block based on the MIP matrix, deriving reconstructed samples for the current block based on the MIP samples, wherein for the current block of which size is equal to 64x4, the MIP flag information for the current block is obtained from the bitstream, and wherein the MIP matrix is derived further based on a width and a height of the current block.

Matrix intra prediction-based image coding apparatus and method

A method for decoding an image by a decoding apparatus according to the present invention comprises the steps of: deriving predicted samples by performing prediction on a current block; determining whether the current block is to be divided, on the basis of a size and a maximum transform size of the current block; when the current block is determined to be divided, dividing the current block into transform blocks; deriving transform coefficients of the transform blocks; deriving residual samples by performing an inverse transform procedure for the transform coefficients; and generating a reconstructed picture on the basis of the residual samples and the predicted samples, wherein, when the size of the current block is larger than the maximum transform size, the current block is determined to be divided.

Method and apparatus for decoding image by using transform according to block size in image coding system

An image decoding method according to the present document comprises the steps of: receiving a bitstream including residual information; deriving a quantized transform coefficient for a current block on the basis of the residual information included in the bitstream; deriving a residual sample for the current block on the basis of the quantized transform coefficient; and generating a restoration picture on the basis of the residual sample for the current block, wherein the residual information includes position information for indicating the position of a transform coefficient, which is not the last 0 in a transform block, and the position information can be derived if a transform skip is not applied to the transform block.

Transform coefficient coding method and device

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

An image decoding method performed by a decoding device according to the present document is characterized by comprising the steps of: acquiring a block-based delta pulse code modulation (BDPCM) available flag about whether a BDPCM is available for a chroma block and a luma block; acquiring, on the basis of the BDPCM available flag, a BDPCM luma flag about whether to apply the BDPCM to the current luma block; and acquiring, on the basis of the BDPCM available flag, a BDPCM chroma flag about whether to apply the BDPCM to the current chroma blocks.

BDPCM-based image decoding method for luma component and chroma component, and device for same

An image decoding method executed by a decoding apparatus according to the present document comprises the steps of: deriving an intra prediction mode of the current chroma block by means of cross-component linear model (CCLM) mode; deriving downsampled luma samples on the basis of the current luma block; deriving downsampled neighboring luma samples on the basis of neighboring luma samples of the current luma block; and deriving the CCLM parameter on the basis of the downsampled neighboring luma samples and neighboring chroma samples of the current neighboring chroma block, wherein the number of down-sampled neighboring luma samples and number of neighboring chroma samples are equal to the previously set thresh-hold value, and the thresh-hold value is derived on the basis of the width and height of the current chroma block.

CCLM prediction-based image decoding method and apparatus in image coding system

A video decoding method performed by a decoding apparatus according to the present document may comprise the steps of: obtaining, from a bitstream, information indicating a level value of a transform coefficient in a current block; selecting one Rice parameter look-up table for the information indicating the level value of the transform coefficient, from among a plurality of Rice parameter look-up tables; deriving a Rice parameter for the information indicating the level value of the transform coefficient on the basis of the selected Rice parameter look-up table; deriving a bin string for the information indicating the level value of the transform coefficient on the basis of the Rice parameter; and deriving the level value of the transform coefficient on the basis of the bin string.

Method and apparatus for coding transform coefficient in video/image coding system

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

An image decoding method performed by a decoding apparatus according to the present disclosure comprises the steps of: obtaining intra prediction information including at least one of MPM flag information, MRL index information, and planner flag information from a bitstream; checking the MPM flag information; checking the MRL index information on the basis of a case where the MPM flag information indicates that the MRL index information is checked; checking the planner flag information on the basis of a case where a value of the MRL index information is 0; deriving an intra prediction mode for a current block on the basis of the check for the planner flag information; deriving prediction samples for the current block on the basis of the intra prediction mode for the current block; and generating a reconstructed picture on the basis of the prediction samples.

Intra prediction method on basis of MPM list and apparatus therefor

According to a disclosure of the present document, information associated with a deblocking filter for performing deblocking filtering may include chroma component filter parameter information associated with deblocking parameter offsets that are applied to a chroma component. The chroma component filter parameter information may be selectively signaled on the basis of a chroma tool offset presence flag. Therefore, an effect of increasing overall coding efficiency may be derived by signaling chroma component filter parameter information only in the case of not a monochrome color format.

Image coding method based on chroma deblocking parameter information for monochrome color format in video or image coding system

An image decoding method carried out by a decoding device, according to the present document, comprises the steps of: acquiring prediction-related information for a current block; acquiring a dependent quantization enable flag related to whether dependent quantization is available; acquiring, on the basis of the dependent quantization enable flag, a transform skip residual coding (TSRC) enable flag related to whether TSRC is available; acquiring residual information of residual coding syntax for the current block, which has been derived on the basis of the TSRC enable flag; deriving motion information of the current block on the basis of the prediction-related information; deriving a prediction sample of the current block on the basis of the motion 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 associated with transform skip residual coding, and device therefor

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

Apparatus and method for coding image

A method for decoding a video performed by a decoding device according to the present document is characterized by comprising: a step for acquiring video information including prediction mode information and residual information through a bitstream; a step for deriving a prediction mode of a current block on the basis of the prediction mode information; a step for deriving a prediction sample on the basis of the prediction mode; a step for deriving a current residual coefficient on the basis of residual syntax elements for the current residual coefficient in the current block; a step for deriving a residual sample on the basis of the current residual coefficient; and a step for deriving a reconstructed sample of the current block on the basis of the prediction sample and the residual sample.

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Seoul, South Korea

Jangwon Choi