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; on the basis of 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; on the basis of at least one of the first flag and the second flag, generating prediction samples by performing at least one of intra-prediction and inter-prediction with respect to a current block in the current picture; generating residual samples on the basis of residual information acquired from the image information; and generating reconstruction samples on the basis of the prediction samples and the residu

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: According to embodiment(s) of the present document, multilayer-based coding can be performed. Multilayer-based coding can output a decoded picture based on a target output layer, and the target output layer, for example, can be determined on the basis of an external means or signaling information. According to one embodiment of the present document, the external means can be preferentially used, for the target output layer, more than the signaling information.

Abstract: The present invention relates to an entropy encoding method, an entropy decoding method and to an apparatus using same. The entropy decoding method includes: a step of decoding a bin of a syntax element; and a step of acquiring information on the syntax element based on the decoded bin. In the step of decoding the bin, context-based decoding or bypass decoding is performed for each bin of the syntax element.

Abstract: An image decoding method performed by a decoding device according to the present document comprises the steps of: deriving a value of a variable on the basis of whether a current picture is a first picture of a current access unit (AU) that is a coded video sequence start access unit (CVSS) AU instead of AU 0, wherein the variable indicates whether all picture storage buffers within a decoded picture buffer (DPB) are emptied without being output; updating the DPB on the basis of the variable; and decoding the current picture on the basis of the updated DPB.

Abstract: An image encoding/decoding method and apparatus for signaling a high level syntax (HLS) and a method of transmitting a bitstream are provided. An image decoding method according to the present disclosure may include obtaining first information indicating whether to constrain luma mapping with chroma scaling (LMCS), obtaining second information indicating whether LMCS for a current video sequence is allowed, and reconstructing a current picture within the current video sequence based on the second information. A value of the second information may be determined based on a value of the first information.

Abstract: According to embodiments of the present document, the subjective/objective quality of an image can be improved through image coding on the basis of subpictures and/or virtual boundaries, and consumption of hardware resources required for coding can be reduced.

Abstract: An image encoding/decoding method and apparatus for signaling an identifier for an APS and a method of transmitting a bitstream are provided. The image decoding method according to the present disclosure may comprise obtaining adaptive parameter set (APS) parameter type information specifying an APS parameter type signaled by an APS, obtaining APS identifier information specifying the APS after obtaining the APS parameter type information, and reconstructing an image based on the APS identifier information.

Abstract: An image decoding method performed by a decoding device according to the present document is characterized by comprising the steps of: acquiring a flag indicating whether a picture header (PH) network abstraction layer (NAL) unit including a PH for the current picture is present; acquiring a video coding layer (VCL) NAL unit including a slice header and slice data for the current slice of the current picture; acquiring the PH on the basis of the flag; and decoding the current picture on the basis of the PH, the slice header, and the slice data.

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: An image encoding/decoding method and device are provided. An image decoding method performed by an image decoding device according to the present disclosure may comprise the steps of: determining a prediction mode of the current block on the basis of prediction information obtained from a bitstream; on the basis of the prediction mode of the current block, obtaining a flag indicating whether a color space transform is applied to a residual sample of the current block; determining a quantization parameter of the current block on the basis of the flag; 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 comprises the steps of: parsing a flag pertaining to a weighted prediction from a bitstream; parsing the syntax of a prediction weighted table from the bitstream based on the flag; performing a weighted prediction for the current block in the current picture based on the prediction weighted table syntax to generate prediction samples for the current block; generating residual samples based on residual information acquired from the bitstream; and generating reconstructed samples for the current block based on the prediction samples and the residual samples, wherein the prediction weighted table syntax can be parsed from the picture header of the bitstream based on the value of the flag being 1, and can be parsed from the slice header of the bitstream based on the value of the flag being 0.

Abstract: An image decoding method performed by a decoding apparatus, according to the disclosure of the present document, comprises the steps of: obtaining, from a bitstream, image information including information related to a temporal sublayer and information related to a target OLS; generating prediction samples of a current block by performing prediction on the current block on the basis of the information related to the temporal sublayer; and generating a reconstructed picture on the basis of the prediction samples.

Abstract: A method by which a video decoding device decodes a video, according to the present document, comprises the steps of: acquiring, from a bitstream, image information including video coding layer (VCL) network abstraction layer (NAL) units; performing inter prediction or intra prediction on the current block within the current picture on the basis of the image information to generate prediction samples about the current block; and restoring the current block on the basis of the prediction samples, wherein the image information includes an sps_video_parameter_set_id syntax element indicating the value of an identifier of a video parameter set, and, on the basis of that the value of the sps_video_parameter_set_id syntax element is 1, the value of the entire output layer set (OLS) number and the value of the number of layers within the OLS, specified by the video parameter set can be derived to be 1.

Abstract: According to the disclosure of the present document, slices included in a current picture are decoded, a picture output flag for the current picture is derived after decoding of all the slices in the current picture is completed, and an output for the current picture may be determined on the basis of the picture output flag. The current picture may be displayed as “not needed for output” on the basis of the value of the picture output flag being 0, and the current picture may be displayed as “needed for output” on the basis of the value of the picture output flag being 1.

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: An image decoding method according to the present invention includes: receiving information on a set of reference pictures for configuring a set of reference pictures of a current picture, wherein the information on the set of reference pictures includes the most significant bit (MSB) information that may calculate the MSB of the picture order count (POC) of a long-term reference picture relative to the current picture, and flag information that represents whether there is MSB information; and eliciting the set of reference pictures by using received MSB information when the flag information is 1, and performing marking on the reference picture, wherein the flag information may be 1 when a temporal sub-layer identifier is 0, and there is at least one POC value for which a remainder obtained by dividing by a maximum value MaxPicOrderCntLsb capable of being represented by the LSB is the same as the least significant bit (LSB) of the POC of the long-term reference picture, in a set of POCs of a previous picture

Abstract: Provided is an image encoding/decoding method and apparatus. The image decoding method may include obtaining first information on whether a current picture might be partitioned, from a bitstream, obtaining, from the bitstream, second information on the number of one or more subpictures included in the current picture based on the first information, deriving one or more subpictures, based on the second information and decoding the one or more subpictures.

Abstract: An image encoding/decoding method and apparatus is provided.

Abstract: An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure is performed by an image decoding apparatus. The image decoding method comprises determining whether a video parameter set (VPS) referenced by a sequence parameter set (SPS) is present, deriving information on inter layer prediction, based on the determination as to whether the video parameter set referenced by the sequence parameter set is present, and reconstructing an image based on the information on inter layer prediction.