Abstract:
A method and device for encoding/decoding an image supporting a plurality of layers are disclosed. The method for decoding the image includes the step of receiving a bitstream including information on a decoding target block of the current layer, the step of entropy decoding the bitstream and obtaining a 1D array of transformation coefficients of the decoding target block; the step of scanning the 1D array of the transformation coefficients according to a scan order and re-arranging it as a 2D array of the transformation coefficients, the step of inversely quantizing the 2D array of the transformation coefficients and obtaining a 2D array of transformation coefficients inversely quantized for the decoding target block, and the step of predicting the decoding target block based on a prediction mode for the decoding target block.
Abstract:
According to embodiments described herein, sub-pictures and/or virtual boundaries can be used for coding an image. For example, sub-pictures in the current picture can be used for predicting, reconstructing, and/or filtering the current picture. Virtual boundaries can be used for filtering reconstructed samples of the current picture. Through image coding based on the subpictures and/or virtual boundaries according to embodiments described herein, the subjective/objective quality of an image can be improved, and the consumption of hardware resources necessary for the coding can be reduced.
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.
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 method by which a decoding device decodes an image, according to the present document, comprises the steps of: obtaining image information from a bitstream; generating a reconstructed picture of the current picture; deriving deblocking filter parameter information related to deblocking filter parameters on the basis of the image information; and performing deblocking filtering on the reconstructed picture on the basis of the deblocking filter parameters so as to generate a modified reconstructed picture.
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 transmission device of point cloud data, a method performed by the transmission device, a reception device and a method performed by the reception device are provided. A method performed by a reception device of point cloud data comprises acquiring temporal scalability information of a point cloud in a three-dimensional space based on a G-PCC file and reconstructing the three-dimensional point cloud based on the temporal scalability information. The temporal scalability information may include a first syntax element for an identifier of a temporal level of a sample in a temporal level track, and wherein an identifier value of the temporal level may be expressed as a discrete value.
Abstract:
A transmission device of point cloud data, a method performed by the transmission device, a reception device and a method performed by the reception device are provided. A method performed by a reception device of point cloud data comprises acquiring temporal scalability information of a point cloud in a three-dimensional space based on a G-PCC file and reconstructing the three-dimensional point cloud based on the temporal scalability information. The temporal scalability information may comprise a first syntax element and a second syntax element for the three-dimensional point cloud, the first syntax element may indicate the number of temporal levels in a track, the second syntax element may indicate whether the three-dimensional point cloud is carried in multiple temporal level tracks, and the second syntax element may be determined based on a value of the first syntax element.
Abstract:
The present invention relates to a method for signaling image information and to a decoding method using same. The method for signaling image information according to the present invention comprises: a step of performing inter-prediction for a current picture; and a step of signaling information including the result of said inter-prediction and reference picture information indicating reference pictures usable in said inter prediction, wherein said reference picture information contains pieces of picture order count (POC) information of said usable reference pictures. The POC information of said usable reference pictures in said reference picture information is configured such that POCs for the pictures existing before said current picture in terms of a POC sequence are located at the front, and POCs for the pictures existing after said current picture in terms of a POC sequence are located following the POCs located at the front.
Abstract:
Provided are a transmission device of point cloud data, a method performed by the transmission device, a reception device, and a method performed by the reception device. The method performed by a reception device of point cloud data according to the present invention comprises the steps of: obtaining a geometry-based point cloud compression (G-PCC) file including the point cloud data; determining whether temporal scalability information of a tile track is present in the G-PCC file; and deriving the temporal scalability information of the tile track on the basis of the temporal scalability information of the tile track being absent, wherein the temporal scalability information of the tile track may be derived on the basis of temporal scalability information of a tile base track in the G-PCC file.