Abstract: A method for image decoding, according to the present document, may comprise the steps of: deriving an intra prediction mode of a chroma block as a cross-component linear model (CCLM) mode; updating the intra prediction mode of the chroma block on the basis of an intra prediction mode of a luma block corresponding to the chroma block; and determining an LFNST set including LFNST matrices on the basis of the updated intra prediction mode, wherein the updated intra prediction mode is derived as an intra prediction mode corresponding to a specific position in the luma block, and the specific position is set on the basis of a color format of the chroma block.

Abstract: According to embodiments according to the present document, merge mode motion vector differences (MMVD) and symmetric motion vector differences (SMVD) may be performed on the basis of reference picture types and, in particular, short-term reference pictures may be used. Accordingly, prediction performance and coding efficiency in an inter prediction mode may be increased.

Abstract: An image decoding method according to the present document comprises the steps of: on the basis of an intra prediction mode of a chroma block being a cross-component linear model (CCLM) mode and an intra prediction mode of a luma block corresponding to the chroma block being a palette mode, updating the intra prediction mode of the chroma block to an intra DC mode; on the basis of the updated intra prediction mode, determining an LFNST set including LFNST matrices; and performing LFNST on the chroma block on the basis of an LFNST matrix derived from the LFNST set, wherein the intra DC mode is an intra prediction mode corresponding to a specific location within the luma block.

Abstract: Disclosed are a method for decoding a video signal and an apparatus therefor. Specifically, a method for decoding an image may include: partitioning a current coding tree block into a plurality of coding blocks so that coding blocks partitioned from the current coding tree block are included in a current picture when the current coding tree block is out of a boundary of the current picture; parsing a first syntax element indicating whether a current coding block is partitioned into a plurality of subblocks when the current coding block satisfies a predetermined condition; and determining a split mode of the current coding block based on the syntax element.

Abstract: A video decoding method according to this disclosure includes: deriving an L0 motion vector and an L1 motion vector for a current block; deriving a refined L0 motion vector and a refined L1 motion vector, by applying DMVR to the current block based on DMVR flag information; deriving L0 prediction samples of the current block based on the refined L0 motion vector and L1 prediction samples of the current block based on the refined L1 motion vector; deriving prediction samples for the current block based on the L0 prediction samples and the L1 prediction samples, by applying BDOF to the current block based on BDOF flag information; and generating reconstruction samples for the current block based on the prediction samples, in which the DMVR flag information is derived based on a predetermined DMVR application condition, and the BDOF flag information is derived based on a predetermined BDOF application condition.

Abstract: A method by which a decoding device decodes an image, according to the present document, comprises the steps of: generating a restoration picture on the basis of prediction samples of a coding block; deriving a boundary strength (BS) for a boundary of the coding block in the restoration picture; performing deblocking filtering on the boundary of the coding block on the basis of the boundary strength; and deriving a modified restoration picture for the restoration picture on the basis of the deblocking filtering, wherein the boundary strength is derived on the basis of a prediction mode of a first block and a second block that are adjacent to the boundary of the coding block, and the prediction mode of the first block or the second block is derived on the basis of whether the prediction mode of the first block or the second block is a current picture referencing (CPR) mode to be coded in reference to a current picture.

Abstract: 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.

Abstract: According to an embodiment disclosed in the present document, it is possible to derive a history-based motion vector prediction (HMVP) buffer for a current block based on a history, and to derive motion information of the current block based on an HMVP candidate included in the HMVP buffer, thereby increasing inter prediction efficiency.

Abstract: The present disclosure relates to an image decoding and encoding method which can efficiently perform inter-prediction by applying a regular merge mode to the current block on the basis of the case in which an MMVD mode, a merge sub-block mode, a CIIP mode, and a partitioning mode, in which prediction is performed by dividing the current block into two partitions, are not available for the current block.

Abstract: 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.

Abstract: A decoding method performed by a decoding device, according to the present document, may comprise the steps of: acquiring a sequence parameter set from a bitstream; acquiring a combined inter-picture merge and intra-picture prediction (CIIP) enable flag from the sequence parameter set; determining, on the basis of the CIIP enable flag and the size of a current block, whether a regular merge flag is included in the bitstream; parsing the regular merge flag in the bitstream on the basis that a condition based on the CIIP enable flag and a condition based on the size of the current block are satisfied; generating prediction samples of the current block on the basis of the regular merge flag; and generating a restoration picture on the basis of the prediction samples.

Abstract: 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.

Abstract: 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.

Abstract: An image decoding method performed by the decoding apparatus according to this document comprising deriving a temporary reference motion vector for a current block based on a reference candidate block of the current block, deriving a reference motion vector by compressing the temporary reference motion vector based on a shifting operation, deriving a motion vector for the current block based on the reference motion vector, deriving prediction samples for the current block based on the motion vector for the current block, and generating reconstructed samples for the current block based on the prediction samples for the current block, wherein a total number of bits of the binary code representing the reference motion vector is less than a total number of bits of the binary code representing the temporary reference motion vector.

Abstract: An image decoding method according to the present document may comprise the steps of: deriving an inter prediction mode from encoded information; configuring reference picture lists, deriving motion information comprising reference picture indexes for symmetric motion vector differences (SMVD); and generating prediction samples on the basis of the motion information, wherein the reference picture indexes for SMVD can be derived on the basis of short-term reference pictures included within the reference picture lists.

Abstract: In the present disclosure, a method of decoding a video signal and a device therefor are disclosed. Specifically, a method of decoding an image based on an inter prediction mode includes deriving a motion vector of an available spatial neighboring block around a current block; deriving a collocated block of the current block based on the motion vector of the spatial neighboring block; deriving a motion vector in a sub-block unit in the current block based on a motion vector of the collocated block; and generating a prediction block of the current block using the motion vector derived in the sub-block unit, wherein the collocated block may be specified by the motion vector of the spatial neighboring block in one pre-defined reference picture.

Abstract: A multilayer-based image decoding method performed by a decoding device, according to the disclosure of the present document, comprises the steps of: obtaining image information including information related to a reference picture list from a bitstream; deriving the reference picture list on the basis of the information related to the reference picture list; generating prediction samples of a current block by performing prediction on the current block on the basis of a reference picture included in the reference picture list; and generating a reconstructed picture including reconstructed samples on the basis of the prediction samples.

Abstract: An image decoding method according to the present document includes obtaining motion prediction information for a current block from a bitstream, generating an affine MVP candidate list for the current block, deriving CPMVPs for CPs of the current block based on the affine MVP candidate list, deriving CPMVDs for the CPs of the current block based on the motion prediction information, deriving CPMVs for the CPs of the current block based on the CPMVPs and the CPMVDs, and deriving prediction samples for the current block based on the CPMVs.

Abstract: 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.

Abstract: According to an embodiment disclosed in the present specification, a history-based motion vector prediction (HMVP) candidate set with respect to a current block may be derived based on a history, the HMVP candidate set may be updated or initialized according to a condition, and motion information of the current block may be derived based on the HMVP candidate set, through which inter prediction efficiency can be improved.