Abstract: A video decoding method includes: segmenting to-be-decoded coefficients according to a scan order of a scan region-based coefficient coding (SRCC) scan region in a coding block of a video image frame to obtain one or more coefficient parts each including a plurality of coefficients; decoding a coefficient part all zero flag of each of the coefficient parts to obtain a value of the coefficient part all zero flag; decoding a significant flag of each coefficient in the coefficient part according to the scan order in response to the value of the coefficient part all zero flag being a preset first value, the significant flag being used for indicating whether the coefficient is a non-zero coefficient; and setting the significant flag of each coefficient in the coefficient part to zero, in response to the value of the coefficient part all zero flag being a preset second value.

Abstract: An encoder includes circuitry and memory connected to the circuitry. In operation, the circuitry: stores MV information and correction processing information into a FIFO buffer for an HMVP mode in association, the MV information being derived for a processed block and correction processing information being related to correction processing of a prediction image of the processed block; registers, in a prediction candidate list for a merge mode, one or more prediction candidates each being a combination of MV information and correction processing information, the prediction candidates including a prediction candidate which is a combination of the motion vector information and the correction processing information stored in the FIFO buffer; and selects a prediction candidate from the prediction candidate list when a current block is to be processed in the merge mode, and performs correction processing of a prediction image of the current block, based on the correction processing information.

Abstract: An image decoding method according to the present document may comprise: a step of deriving transform coefficients for a current block by performing inverse quantization on the basis of residual information; and a step of deriving modified transform coefficients by applying LFNST to the transform coefficients, wherein the step of deriving the transform coefficients comprises a step of parsing position information of a last non-zero transform coefficient, an LFNST index related to application of the LFNST is parsed after parsing a position of the last non-zero transform coefficient, and the transform coefficients are derived after parsing the LFNST index.

Abstract: A decoder includes a memory and a processor coupled to the memory. The processor is configured to obtain first information from a bitstream, the first information indicating a number of first points in a current picture. The processor is also configured to determine second information provided for each of the first points based on the first information, the second information indicating a difference between a coordinate value of a first point and a coordinate value of a corresponding second point, the corresponding second point being included in a reference picture. The processor is further configured to generate a prediction image of a current block by performing an affine prediction according to the determined second information.

Abstract: A video decoding method performed by a decoding apparatus according to the present document comprises the steps of: receiving a bit stream including residual information of a current block; deriving a specific number of the number of context encoding bins for context syntax elements for a current sub-block of the current block; decoding the context syntax elements for the current sub-block included in the residual information on the basis of the specific number; deriving transform coefficients for the current sub-block on the basis of the decoded context syntax elements; deriving residual samples for the current block on the basis of the transform coefficients; and generating a reconstructed picture on the basis of the residual samples.

Abstract: A method of decoding a bitstream by an electronic device is provided. The method receives an image frame of a bitstream and determines a block unit having a block width and a block height based on the received image frame. The method determines whether a geometric partitioning mode is disabled for the block unit based on a comparison between the block width and the block height. The method divides the block unit to generate multiple sub-blocks predicted by different merge candidates of the block unit when the geometric partitioning mode is enabled and applied on the block unit. The predicted block is generated by predicting block unit based on a prediction mode different from the geometric partitioning mode when the geometric partitioning mode is disabled for the block unit. The method them reconstructs the block unit based on the predicted block.

Abstract: Systems, methods and apparatus for encoding or decoding a file format that stores one or more images are described. One example method includes performing a conversion between a visual media file and a bitstream of a visual media data according to a format rule, wherein the format rule specifies a characteristic of a syntax element in the visual media file, and wherein the format rule specifies that the syntax element that has a value indicative of a level identification is coded in any one or both of a subpicture common group box or a subpicture multiple groups box using eight bits.

Abstract: A method comprising obtaining a bitstream, the bitstream comprises a transform unit syntax and a coding unit syntax, the transform unit syntax includes a value of a first flag and a value of a second flag related to, respectively, a first chroma transform block and a second chroma transform block of a current transform unit or a current sub-transform unit within the current transform unit, the first or second flag specifies whether the first or second chroma transform block contains at least one transform coefficient levels not equal to 0, the coding unit syntax includes a value of a third flag specifying whether a transform tree structure is present or not; and deriving a value of a fourth flag based on the values of the first, second, and third flags, the fourth flag specifies whether a luma transform block contains at least one transform coefficient levels not equal to 0.

Abstract: Aspects of the disclosure provide methods, apparatuses, and non-transitory computer-readable storage mediums for video encoding/decoding. An apparatus includes processing circuitry that partitions a current block of a current picture based on a geometric partitioning mode (GPM). The current block is partitioned into two partitions in the GPM mode. Each of the partitions is associated with a respective predictor. A weighting index for a sample of the current block is determined based on a position of the sample. A weighting factor is calculated based on the weighting index of the sample according to an equation that converts the weighting index to the weighting factor. The sample is encoded based on the weighting factor and the predictor corresponding to the sample.

Abstract: Methods of encoding and decoding for video data are describe in which significance maps are encoded and decoded using non-spatially-uniform partitioning of the map into parts, wherein the bit positions within each part are associated with a given context. Example partition sets and processes for selecting from amongst predetermined partition sets and communicating the selection to the decoder are described.

Abstract: A processing system estimates motion between blocks of images based on differences in pixel activities between blocks. Blocks having similar pixel activities are more likely to be matches for motion estimation than are blocks having dissimilar pixel activities. Accordingly, the processing system compares pixel activity between current block of a current image and candidate blocks within a search area in the reference image, and estimates motion based on a subset of candidate blocks having a difference in pixel activity from that of the current block within a threshold.

Abstract: There is provided a terminal device capable of efficiently performing communication in a communication system in which a base station device and the terminal device communicate with each other. The terminal device that communicates with the base station device by using a plurality of aggregated cells recognizes that a serving cell is stopped in a first state, recognizes that the serving cell is started in a second state, and switches from the first state to the second state based on a received PDCCH.

Abstract: An encoder which transforms a current block to be encoded in an image to encode the current block includes circuitry and memory. The circuitry, using the memory: determines a plurality of first transform basis candidates and transforms the current block using a transform basis included in the plurality of first transform basis candidates determined, when the current block has a first size; and determines one or more second transform basis candidates different from the plurality of first transform basis candidates and transforms the current block using a transform basis included in the one or more second transform basis candidates determined, when the current block has a second size larger than the first size.

Abstract: An image decoding method is disclosed in the present specification. An image decoding method according to the present invention may include: determining a prediction mode of a current block as IBC (Intra Block Copy) mode, deriving a candidate list for deriving a block vector of the current block and deriving a block vector of the current block by using the candidate list, wherein the candidate list is derived based on a size of the current block.

Abstract: An image decoding method performed by a decoding device according to the present invention comprises the steps of: acquiring information on inter prediction of a target block through a bit stream; deriving motion information of the target block on the basis of the information on inter prediction; deriving a prediction sample by performing inter prediction for the target block on the basis of the motion information; generating a reconstruction block on the basis of the prediction sample; deriving modified motion information of the target block on the basis of the reconstruction block; and updating the motion information of the target block on the basis of the modified motion information. According to the present invention, modified motion information of the target block can be calculated, and the motion information of the target block can be updated on the basis of the modified motion information, so that the overall coding efficiency can be improved.

Abstract: Methods, apparatuses, devices and storage media for decoding and encoding are provided. In one aspect, a decoding method includes: obtaining a value of an Enhanced Temporal Motion Vector Prediction (ETMVP) mode flag and an ETMVP mode index value for a current coding unit (CU); when the value of the ETMVP mode flag is a first value, determining coordinate information of an initial matching CU of the current CU according to coordinate information of the current CU; constructing an enhanced temporal candidate list based on the coordinate information of the initial matching CU; determining coordinate information of a target matching CU according to the ETMVP mode index value; and determining motion information of a subblock at a corresponding position in the current CU according to the motion information of the target matching CU.

Abstract: An image decoding method according to the present document comprises a step of deriving a corrected transform coefficient, wherein the step of deriving the corrected transform coefficient comprises the steps of: determining whether LFNST can be applied to the height and width of a divided sub-partition block when an ISP is applied to a current block; parsing a LFNST index when the LFNST can be applied; and deriving the corrected transform coefficient on the basis of the LFNST index and a LFNST matrix.

Abstract: The present invention relates to an intra prediction mode mapping method and a device using the method. The intra prediction mode includes: decoding flag information providing information regarding whether an intra prediction mode of a plurality of candidate intra prediction modes for the current block is the same as the intra prediction mode for the current block, and decoding a syntax component including information regarding the intra prediction mode for the current block in order to induce the intra prediction mode for the current block if the intra prediction mode from among the plurality of candidate intra prediction modes for the current block is not the same as the intra prediction mode for the current block. Thus, it is possible to increase the efficiency with which are images are decoded.

Abstract: An image encoding/decoding method and apparatus are provided. An image decoding method performed by an image decoding apparatus may comprise parsing weight information specifying a weight for a reference sample from a bitstream according to a weight parameter syntax structure, and decoding a current block by performing inter prediction based on the weight information. The parsing according to the weight parameter syntax structure may comprise obtaining weight number information specifying the number of weight information obtained from the bitstream according to the weight parameter syntax structure and obtaining weight information from the weight parameter syntax structure based on the weight number information.

Abstract: A coding device and a decoding device are configured to include an estimated prediction mode deciding section (122a) including: a reference block selecting section (1223a) for selecting a reference block for use in estimating an intra-prediction mode for a subject block; an estimating number deciding section (1222a) for deciding an estimating number of estimated values to be estimated for the intra-prediction mode; and an estimated prediction mode deriving section (1221a) for estimating, based on a reference block, the estimating number of estimated values of the prediction mode.