Lg Electronics Inc.

Rosedale Dynamics LLC

Guangdong Oppo Mobile Telecommunications Corp., Ltd.

Vivo Mobile Communication Co., Ltd.

Beijing Xiaomi Mobile Software Co., Ltd.

Xiaomi Inc.

Tcl King Electrical Appliances (Huizhou) Co. Ltd.

Nokia Technologies Oy

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

Jung Ah Choi

Summi Yoo

A method for decoding an image by a decoding device according to the present document comprises the steps of: receiving prediction-related information of a current block; deriving an intra prediction type of the current block on the basis of the prediction-related information; forming an intra prediction mode candidate list of the current block on the basis of intra prediction modes of blocks neighboring the current block; deriving an intra prediction mode of the current block on the basis of the intra prediction mode candidate list; and deriving reference samples of the current block on the basis of the intra prediction type and the intra prediction mode, and deriving a prediction sample on the basis of the reference samples.

Method and device for decoding image by using intra prediction mode candidate list in image coding system

According to the disclosure of the present document, dependency conditions can be defined for efficiently parsing/signaling syntax elements having dependency on transform skip- and/or palette coding-related information, and, on the basis of the dependency conditions, whether or not to parse the transform skip- and/or palette coding-related information can be determined. Accordingly, bits that need to be signaled for video/image coding can be reduced, and coding efficiency can be improved.

Image or video coding based on transform skip- and palette coding-related advanced syntax element

An image encoding/decoding method and apparatus are provided. An image decoding method performed by an image decoding apparatus may include obtaining a residual block of a current block encoded in an intra prediction mode from a bitstream, deriving a modified residual block by performing differential encoding with respect to the residual block, based on differential encoding mode information obtained from the bitstream indicating a differential encoding mode of a residual coefficient, and deriving a residual block of the current block by performing dequantization with respect to the modified residual block.

Method and device for coding/decoding image using differential coding of residual coefficient, and method for transmitting bitstream

An image decoding method, which is performed by a decoding device according to the present document, is characterized by including: a step for receiving a bitstream including residual information about the current block; a step for deriving a maximum value of the number of context-encoding bins for context syntax elements coded on the basis of context included in the residual information; a step for entropy-decoding the context syntax elements on the basis of the maximum value; a step for deriving conversion coefficients for the current block on the basis of the entropy-decoded context syntax elements; a step for deriving a residual sample for the current block on the basis of the conversion coefficients; and a step for generating a reconstructed picture on the basis of the residual sample for the current block.

Image decoding method and device using residual information in image coding system

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.

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Seoul, South Korea

Jangwon Choi