Abstract: According to the disclosure of the present document, a recovery point picture order count (POC) for a gradual decoding refresh (GDR) picture is derived on the basis of GDR-related information, and an output for pictures related to the GDR picture is determined on the basis of the recovery point POC. The recovery point DOC can be derived on the basis of a syntax element related to the recovery point POC.

Abstract: An image encoding/decoding method and apparatus for signaling PTL, DPB and HRD related information in SPS and a method of transmitting a bitstream are provided. The image decoding method may comprise obtaining flag information indicating whether a profile tier level (PTL) syntax structure, a decoded picture buffer (DPB) parameter syntax structure and a hypothetical reference decoder (HRD) parameter syntax structure are present in a sequence parameter set (SPS), obtaining at least one among the PTL syntax structure, DPB parameter syntax structure and HRD parameter syntax structure, based on the flag information, and processing a current output layer set (OLS), based on the obtained syntax structure. The flag information may have a predetermined value, based on that an OLS including only one layer having the same layer identifier as a layer identifier of the SPS is present.

Abstract: An image encoding/decoding method and apparatus for signaling decoded picture buffer (DPB) related information and profile tier level (PTL) related information and a method of transmitting a bitstream are provided. The image decoding method according to the present disclosure may comprise obtaining first information indicating the number of one or more decoded picture buffer (DPB) parameter syntax structures in a video parameter set (VPS), obtaining the one or more DPB parameter syntax structures from the VPS based on the first information, obtaining second information between one or more multi-layer output layer sets (OLSs) and the one or more DPB parameter syntax structures from the VPS based on the first information, selecting a DPB parameter syntax structure that applies to a current OLS based on the second information, and processing the current OLS based on the selected DPB parameter syntax structure.

Abstract: A video decoding method performed by a video decoding device according to the present document may comprise the steps of: parsing, from a bitstream, number information relating to the number of slices each having an explicitly signaled height in a tile of a current picture; on the basis of the number information, parsing, from the bitstream, height information relating to heights of the slices each having an explicitly signaled height; when a value of the number information is n, deriving heights of 0-th to (n?1)-th slices in the tile on the basis of the height information; deriving the height of the n-th slice in the tile on the basis of the height of the (n?1)-th slice; deriving a height of a last slice in the tile on the basis of a height remaining after subtracting the sum of heights of the other slices in the tile from a height of the tile; deriving the number of slices in the tile; and decoding the current picture on the basis of slices of the current picture.

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: A video decoding method performed by a video decoding device according to this document comprises the steps of: parsing prediction weighted table syntax from a bitstream; parsing information on the number of reference pictures in a reference picture list from the prediction weighted table syntax; deriving weights for weighted prediction on the basis of the information on the number of reference pictures; deriving prediction samples of a current block by performing weighted prediction for the current block on the basis of the weights; and reconstructing a current picture on the basis of the prediction samples, wherein the prediction weighted table syntax may be parsed from a picture header of the bitstream.

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 method or coding image information, according to the present invention, comprises the steps of: binarizing according to different techniques, index values of forward prediction, backward prediction, and bidirectional prediction, depending on whether the bidirectional prediction is applied when inter-predicting a current block; and entropy coding a binarized codeword, wherein whether to apply the bidirectional prediction when inter-predicting the current block can be determined on the basis of the size of the current block. As a result, provided are a method for binarizing an inter-prediction direction of a prediction unit having a specific size, and an apparatus using same.

Abstract: An image decoding method performed by a decoding apparatus according to the present disclosure comprises the steps of: obtaining image information including HRD-related information relating to a target OLS, wherein the target OLS is one of OLSs including a plurality of layers; determining whether an HRD parameter syntax structure relating to the target OLS exists, on the basis of the HRD-related information; deriving an HRD parameter syntax structure relating to the target OLS on the basis of a result of the determination; performing a DPB management process relating to a DPB on the basis of the HRD parameter syntax structure for the target OLS; and decoding a current picture on the basis of the DPB.

Abstract: According to the present invention, an inter prediction method comprises the steps of: generating a merge candidate list for a block to be predicted, wherein the block is to correspond to a current prediction unit; deriving, on the basis of one of a plurality of merge candidates constituting the merge candidate list, motion information on the block to be predicted; and performing, on the basis of the derived motion information, a prediction on the block to be predicted so as to generate a prediction block corresponding to the current prediction unit.

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: Disclosed herein are an image encoding/decoding method and apparatus for signaling hypothetical reference decoder (HRD) related parameters, and a method of transmitting a bitstream. An image decoding method may comprise obtaining first information specifying the number of one or more hypothetical reference decoder (HRD) parameter syntax structures in a video parameter set (VPS), obtaining the one or more HRD parameter syntax structures from the VPS based on the first information, obtaining second information on mapping between one or more multi-layer output layer sets (OLSs) and the one or more HRD parameter syntax structures from the VPS based on the first information, selecting a HRD parameter syntax structure that applies to a current OLS based on the second information, and processing the current OLS based on the selected HRD parameter syntax structure.

Abstract: An image encoding/decoding method and apparatus are provided. An image decoding method may comprise determining whether an inter slice type is allowed for a current picture including a current block, determining whether an intra slice type is allowed for the current picture, based on the inter slice type being allowed for the current picture, and decoding the current block based on a slice type allowed for the current picture. Whether the inter slice type is allowed for the current picture may be determined based on a picture type of the current picture and whether a current layer including the current picture is able to use inter-layer prediction.

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: 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: According to the disclosure of the present document, image information acquired through a bitstream may include a picture header including information related to a reference picture list, the picture header may include a non-reference picture flag related to whether a current picture is not used as a reference picture, and the non-reference picture flag may be included in a fixed location relative to a starting point of the picture header in the picture header. As a result, it is possible to derive the effect of enhancing prediction performance and coding efficiency in a video/image coding.

Abstract: An image decoding method performed by a decoding apparatus, according to the present disclosure, comprises the steps of: obtaining indication information including a first flag which indicates whether signaling of a reference picture list, to be applied to a current block, is applied at a picture level or a slice level; on the basis of the first flag, parsing, from a picture header or a slice header, information related to the signaling of the reference picture list; performing inter-prediction on the basis of the information related to the signaling of the reference picture list so as to derive prediction samples for the current block; and generating, on the basis of the prediction samples, reconstructed samples for the current block.

Abstract: According to the disclosure of the present document, image information acquired via a bitstream includes POC information, and a non-reference picture flag related to whether a picture is not used as a reference picture. A POC value of a current picture is derived on the basis of the POC information, and the POC information includes POC information of a previous picture in decoding order for the current picture. The previous picture in the decoding order for deriving the POC value of the current picture may be limited to a picture where a value of the non-reference picture flag is 0. Accordingly, an incorrect POC value can be prevented from being derived in video/image coding.

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: A method for decoding an image according to the present invention comprises the steps of: receiving and decoding MPM index information for indicating an MPM candidate which is to be used as an intra prediction mode of a current block; generating an MPM candidate list containing a plurality of MPM candidates for the current block; determining the MPM candidate indicated by the decoded MPM index information as the intra prediction mode of the current block, among the plurality of the MPM candidates which constitute the MPM candidate list; and generating a prediction block corresponding to the current block by performing intra prediction for the current block based on the determined intra prediction mode.