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

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

An image decoding method performed by a decoding apparatus according to the present document is characterized by comprising the steps of: acquiring image information; and generating a reconstructed picture on the basis of the image information.

Image decoding method and apparatus therefor

A video decoding method according to the present document is characterized by comprising: obtaining Most Probable Mode (MPM) index information and reference line index information from a bitstream; compiling an MPM list including candidate intra prediction modes for the intra prediction of a current block; deriving an intra prediction mode for the current block from among the candidate intra prediction modes included in the MPM list on the basis of the MPM index information; generating prediction samples for the current block on the basis of the intra prediction mode; and generating reconstructed samples for the current block on the basis of the prediction samples, wherein the step for compiling the MPM list involves deriving a DC mode as one of the candidate intra prediction modes, and including the DC mode in the MPM list, the DC mode being derived on the basis of the value of reference line index information indicating a reference line used for the intra prediction of the current block not being zero.

MPM list-based intra prediction method and device

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 performed by a decoding apparatus according to the present document comprises the steps of: obtaining a sign data hiding availability flag indicating whether or not sign data hiding is available for a current slice; obtaining a TSRC availability flag indicating whether or not TSRC is available for a transform skip block of the current slice; obtaining residual coding information about the transform skip block on the basis of the TSRC availability flag; deriving a residual sample for the transform skip block on the basis of the residual coding information; and generating a reconstruction picture on the basis of the residual sample, wherein the TSRC availability flag is obtained on the basis of the sign data hiding availability flag.

Method and apparatus for decoding imaging related to sign data hiding

An image decoding method performed by a decoding apparatus according to the present document includes deriving a CCLM mode as an intra prediction mode of a current block, deriving a specific value for the current chroma block, deriving, based on the width and the height of the current chroma block being greater than or equal to the specific value, top neighboring chroma samples whose number is equal to the specific value of the current chroma block, and left neighboring chroma samples whose number is equal to the specific value, deriving CCLM parameters based on the top neighboring chroma samples, the left neighboring chroma samples, and down-sampled neighboring luma samples, deriving prediction samples for the current chroma block based on the CCLM parameters and the down-sampled luma samples, and generating reconstructed samples for the current chroma block based on the prediction samples, wherein the derived specific value is 2.

Method and device for image decoding on basis of CCLM prediction in image coding system

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.

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Seoul, South Korea

Jangwon Choi