Abstract: According to the disclosure of the present document, scaling list data transferred from an adaptation parameter set (APS) can be signaled through a hierarchical structure, and restrictions are placed on the scaling list data transferred from the APS, whereby the amount of data to be signaled for video/image coding can be reduced, and easiness in implementation can be provided.

Abstract: An image encoding/decoding method and apparatus are provided. The image decoding method performed by the image decoding apparatus, according to the present disclosure, comprises the steps of: determining a current block by splitting an image on the basis of split information acquired from a bitstream; determining a quantization parameter of the current block; and determining a transform coefficient of the current block on the basis of the quantization parameter.

Abstract: A video decoding method performed by a video decoding device according to the present document may comprise the steps of: acquiring image information from a bitstream, the image information including a picture header associated with the current picture including a plurality of slices; parsing, from the picture header, at least one of a first flag indicating whether information necessary for an inter-prediction operation for a decoding process is present in the picture header, or a second flag indicating whether information necessary for an intra-prediction operation for the decoding process is present in the picture header; generating prediction samples by performing at least one of intra-prediction or inter-prediction for the slices in the current picture on the basis of at least one of the first flag or the second flag; and generating reconstructed samples on the basis of the prediction samples.

Abstract: Disclosed herein are an image encoding and decoding method and apparatus for signaling information on the number of DPB parameters, and a recording medium storing a bitstream. An image decoding method may comprise obtaining first information indicating the number of decoded picture buffer (DPB) parameter syntax structures in a video parameter set (VPS), computing the number of DPB parameter syntax structures in the VPS based on the first information, obtaining the DPB parameter syntax structures in the VPS based on the number of DPB parameter syntax structures, and managing a DPB based on the DPB parameter syntax structures.

Abstract: A video decoding method executed by a video decoding apparatus according to the present document comprises the steps of: parsing a flag associated with weighted prediction from a bitstream; on the basis of the flag, parsing a prediction weighted table syntax from the bitstream; and on the basis of the prediction weighted table syntax, executing a weighted prediction on a current block in a current picture to reconstruct the current picture, wherein on the basis of the value of the flag being 1, the prediction weighted table syntax may be parsed from a picture header of the bitstream, and on the basis of the value of the flag being 0, the prediction weighted table syntax may be parsed from a slice header of the bitstream.

Abstract: A method for decoding an image by a decoding device according to the present invention comprises the steps of: deriving, from a bit stream, transform coefficients of a block to be decoded; deriving residual samples of the block to be decoded, on the basis of a selective transform of the transform coefficients; and generating a reconstructed picture on the basis of the residual samples of the block to be decoded and prediction samples of the block to be decoded, wherein the selective transform is performed on the basis of a modified transform matrix, the modified transform matrix comprises a matrix including a modified basis vector, and the modified basis vector contains a certain number of elements selected from N elements.

Abstract: According to an image coding method according to embodiments of the present document, information related to in-loop filtering may be efficiently signaled, and repetitive procedures for signaling subpicture-related information may be reduced.

Abstract: An image decoding method performed by a decoding device, according to the present document, comprises the steps of: deriving a chroma quantization parameter table on the basis of quantization parameter data; deriving a quantization parameter for combined chroma coding on the basis of the chroma quantization parameter table; deriving prediction samples of a current chroma block on the basis of prediction information; deriving transform coefficients of the current chroma block on the basis of residual information; deriving residual samples by dequantizing the transform coefficients on the basis of the quantization parameter; and generating a reconstructed picture on the basis of the prediction samples and the residual samples.

Abstract: Embodiments of the disclosure provide methods and devices for decoding video signals using inter prediction. According to an embodiment of the disclosure, a method for processing a video signal comprises constructing a reference picture list of a current picture in the video signal and performing a prediction for a current picture by using the reference picture list, wherein constructing the reference picture list comprising, if a first entry of the reference picture list corresponds to a short-term reference picture (STRP), obtaining a picture order count (POC) difference between a picture related to the first entry and another picture, and if a second entry of the reference picture list corresponds to a long-term reference picture (LTRP), obtaining a POC modulo value of a picture related to the second entry. A reference picture list for identifying a picture may be generated in a simplified and effective manner. Thus, the compression performance may be increased, and the computation time may be decreased.

Abstract: A video decoding method performed by a video decoding device according to the present document may comprise the steps of: acquiring image information from a bitstream, wherein the image information includes a picture header associated with a current picture, and the current picture includes multiple slices; based on the picture header, acquiring at least one of a first flag indicating whether information required for an inter-prediction operation exists in the picture header and a second flag indicating whether information required for an intra-prediction operation exists in the picture header; based on at least one of the first flag and the second flag, generating prediction samples.

Abstract: An image decoding method, according to the present disclosure may comprise: acquiring, from a bitstream, image information including adaptive loop filter (ALF) information including, alternative filter information for a chroma component of a current block, and residual information; generating reconstructed samples for the current block on the basis of the residual information; and generating modified reconstructed samples for the chroma component of the current block on the basis of the alternative filter information.

Abstract: According to the present document, a video decoding method performed by a video decoding apparatus may comprise the steps of: parsing a first flag and a second flag from a bitstream, wherein the first flag is related to whether weighted prediction is applied to slices referring to a picture parameter set, and the second flag is related to whether information relating to the weighted prediction exists in a picture header; parsing a prediction weighted table syntax from the picture header based on the first flag and the second flag; generating prediction samples for a current block in a current picture based on syntax elements within the prediction weighted table syntax; generating residual samples based on residual information; and generating reconstructed samples based on the prediction samples and the residual samples, wherein the second flag is parsed from the picture parameter set based on the first flag.

Abstract: According to embodiments of the present document, information for performing in-loop filtering by crossing virtual boundaries can be efficiently signaled. In one embodiment, the value of a virtual boundary-related flag signaled through a picture header can be determined on the basis of the value of a virtual boundary-related flag signaled through an SPS.

Abstract: According to the disclosure of the present document, scaling list data transmitted from an adaptation parameter set (APS) can be signaled through a hierarchical structure. In addition, by setting a limit on the scaling list data transmitted from the APS, it is possible to reduce the amount of data which has to be signaled for video/image coding, and facilitate implementation.

Abstract: Provided are an image encoding/decoding method and device. An image decoding method performed by an image decoding device according to the present disclosure includes the steps of: determining a quantization parameter of the current block on the basis of whether color space conversion is applied to a residual sample of the current block; determining a transform coefficient of the current block on the basis of the quantization parameter; determining the residual sample of the current block by using the transform coefficient; and resetting the value of the residual sample on the basis of whether the color space conversion is applied.

Abstract: According to embodiment(s) of the present document, computational overhead and complexity can be reduced by using a 0th-order exponential Golomb coding scheme (ue(v)) for procedures of parsing syntax elements/information about absolute values of luma/chroma ALF filter coefficients. In addition, coding using ue(v) can be efficiently performed by fixing the range of values of the information about the absolute values of the luma/chroma ALF filter coefficients.

Abstract: An image decoding method, according to the present disclosure may comprise: acquiring, from a bitstream, image information including adaptive loop filter (ALF) information including, alternative filter information for a chroma component of a current block, and residual information; generating reconstructed samples for the current block on the basis of the residual information; and generating modified reconstructed samples for the chroma component of the current block on the basis of the alternative filter information.

Abstract: An image encoding/decoding method and apparatus for signaling a VPS and a recording medium storing a bitstream are provided. An image decoding method may comprise obtaining first information indicating whether each output layer set (OLS) specified by a video parameter set (VPS) includes only one layer, obtaining second information indicating the number of decoded picture buffer (DPB) parameter syntax structures in the VPS, based on the first information, obtaining the DPB parameter syntax structures in the VPS based on the second information, and managing a DPB based on the DPB parameter syntax structures.

Abstract: According to the disclosure of the present document, information regarding ALF filter coefficients may be encoded/decoded by fixed order-based exponential golomb coding. In addition, information regarding a fixed filter in ALF may be binarized by fixed-length coding. Accordingly, signaling efficiency can be increased, and coding complexity can be decreased.

Abstract: According to embodiments of the present document, a zero-order exponential Golomb coding scheme(ue(v)) is used for a parsing procedure of an information/syntax element related to luma/chroma ALF filter coefficient absolute values, so that operational overhead and complexity can be reduced. In addition, since the range of values of the information related to the luma/chroma ALF filter coefficient absolute values is fixed, coding that uses ue(v) can be efficiently performed.