Abstract: An image decoding/encoding method and device according to the present disclosure enable: an intra prediction mode of the current block to be determined on the basis of whether the intra prediction mode of the current block is derived on the basis of a cost of a template area adjacent to the current block; a reference sample of the current block to be determined; and a prediction sample of the current block to be generated on the basis of the intra prediction mode and the reference sample.

Abstract: A method comprising: obtaining an image block unit comprising samples in color channels of one or two chrominance channels and one luminance channel (800); reconstructing samples of said luminance channels of the image block unit (802); predicting samples of at least one color channel of image block unit using a cross-component prediction model based on reconstructed samples on a reference channel, wherein parameters of the cross-component prediction model are determined at least partly based on a plurality of reconstructed chrominance samples and their corresponding reconstructed luminance samples in neighboring image block units (804); predicting a plurality of color channel samples in said neighboring image block units co-locating at least part of the reconstructed chrominance and luminance samples using said cross-component prediction model (806); determining a difference between values of the predicted plurality of color channel samples in said neighboring image block and corresponding reconstructed colo

Abstract: Disclosed is a method for video encoding and decod-ing using adaptive color transform on a residual signal. In particular, the maximum memory size required for adaptive color transform is limited by: controlling whether to allow color space conversion on a sequence level according to a syntax element indicating the maximum conversion size allowed for a sequence of pictures; or controlling whether to apply color space conversion on a block level according to the size of a coding block.

Abstract: Disclosed is a method for video encoding and decoding using adaptive color transform on a residual signal. In particular, the maximum memory size required for adaptive color transform is limited by: controlling whether to allow color space conversion on a sequence level according to a syntax element indicating the maximum conversion size allowed for a sequence of pictures; or controlling whether to apply color space conversion on a block level according to the size of a coding block.

Abstract: More suitable image encoding technique and image decoding technique are provided. An image encoding method for encoding an image includes: a predicted image generation step of generating a predicted image of a synthesis prediction by performing synthesis processing of synthesizing a predicted image of an inter prediction and a predicted image of an intra prediction to an encoding-target block; and an encoding step of encoding a difference between the predicted image generated in the predicted image generation step and a pixel value of an image of the encoding-target block, the synthesizing processing includes weighting processing performed to the predicted image of the inter prediction and the predicted image of the intra prediction, and a weighting parameter of the weighting processing is determined in accordance with a type of the intra prediction.

Abstract: More suitable image encoding technique and image decoding technique are provided. An image encoding method for encoding an image includes: a predicted image generation step of generating a predicted image of a synthesis prediction by performing synthesis processing of synthesizing a predicted image of an inter prediction and a predicted image of an intra prediction to an encoding-target block; and an encoding step of encoding a difference between the predicted image generated in the predicted image generation step and a pixel value of an image of the encoding-target block, the synthesizing processing includes weighting processing performed to the predicted image of the inter prediction and the predicted image of the intra prediction, and a weighting parameter of the weighting processing is determined in accordance with a type of the intra prediction.

Abstract: A method of video encoding includes determining whether a current block in a picture satisfies a size requirement. When the current block is determined to satisfy the size requirement, the method includes predicting an intra block copy (IBC) prediction mode usage flag of the current block based on a type of a tile group or a slice to which the current block belongs, determining an IBC prediction mode that is separate from an inter prediction mode and an intra prediction mode based on the inferred IBC prediction mode usage flag, determining a block vector indicating a reference area in the picture when the IBC prediction mode is determined, and encoding the current block based on reference samples in the reference area in the picture.

Abstract: A picture prediction method, encoder, decoder and storage medium are provided. If a current block uses an MIP mode to determine its intra prediction value, the encoder sets a value of an MIP mode parameter as indicating use of the MIP mode and signals into a bitstream; determines the MIP mode of the current block and signals into the bitstream; determines, based on the MIP mode, prediction values for luma and chroma components of the current block. The decoder parses the bitstream and determines an MIP mode parameter of the current block; if its value indicates that the current block uses the MIP mode to determine its intra prediction value, parses the bitstream, determines the MIP mode of the current block and prediction values of luma and chroma components of the current block based on the MIP mode; decodes the current block based on prediction values.

Abstract: An image encoding/decoding method and apparatus are provided. The image decoding method includes obtaining, from a bitstream, network abstraction layer (NAL) unit type information of at least one NAL unit including coded image data, determining a NAL unit type of at least one slice in the current picture based on the obtained NAL unit type information, and decoding the at least one slice based on the determined NAL unit type. The current picture includes a plurality of subpictures having different NAL unit types, the bitstream is a single bitstream obtained by merging a plurality of subpicture bitstreams for the subpictures.

Abstract: A video decoder may be configured to receive a first instance of a flag for a first block, with a first value for the flag indicating that a cross-component prediction (CCP) mode is derived without signaling and a second value for the flag indicating that the CCP mode is signaled; in response to determining that the first instance of the flag is set to the first value, derive a first CCP mode for the first block; determine a first predicted chroma block for the first block using the first CCP mode; determine a decoded version of the first block based on the first predicted chroma block; and output a picture of decoded video data that includes the decoded version of the first block.

Abstract: Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for video decoding. In one method, a decoder determines a fusion scheme applied in decoder-side intra mode derivation (DIMD) mode and in template-based intra mode derivation (TIMD) mode, and the fusion scheme is applied as a weighted average of predictors in the DIMD mode and in the TIMD mode.

Abstract: An image decoding method includes: deriving an L0 motion vector and a L1 motion vector of the current block; deriving prediction samples of the current block based on the L0 motion vector and the L1 motion vector; and generating reconstructed samples of the current block based on the prediction samples. Deriving the prediction samples includes applying bi-directional optical flow (BDOF) to the current block based on whether the condition for applying BDOF to the current block is satisfied, and the application condition of the BDOF includes a condition whereby the values of L0 luma weighted prediction flag information and L1 luma weighted prediction flag information are both zero, where the a value of each of the L0 luma weighted prediction flag information and L1 luma weighted prediction flag information being 0 represents that a weight factor for each of a L0 and L1 prediction luma components does not exist, respectively.

Abstract: An example method of decoding video includes receiving a coded video bitstream comprising a plurality of frames, including a current frame comprising a current block. The method also includes determining whether a first prediction mode is applied to the current block. When the first prediction mode is applied to the current block: obtaining a first motion vector difference (MVD) for the current block by parsing the coded video bitstream; and deriving a second MVD for the current block based on the first MVD. The method further includes obtaining one or more motion vector predictors (MVP) for the current block, generating a motion vector (MV) pair that includes a first MV generated by adding the first MVD to the MVP and a second MV generated by adding the second MVD to the MVP, and decoding the current block using the MV pair.

Abstract: A device for decoding video data includes memory configured to store the video data and processing circuitry. The processing circuitry is configured to determine that a current block of the video data is inter-predicted in a combined inter-intra prediction (CIIP) mode or a geometric partitioning mode (GPM), determine that template matching is enabled for the current block, generate a motion vector for the current block based on template matching; determine a prediction block for the current block based on the motion vector in accordance with the CHIP mode or the GPM, and reconstruct the current block based on the prediction block.

Abstract: At least a method and an apparatus are presented for efficiently encoding or decoding video by adapting Luma mapping with Chroma scaling for 4:4:4 RGB content. For example, a format of an image data of a video to encode is determined to be RGB format; and responsively a RGB mapping is applied to at least one of the color components of the image data wherein a RGB mapping adjusts the dynamic range of a color component of an image data in RGB format. Then, the video is encoded based on the at least one RGB mapped color component.

Abstract: This disclosure relates encoding and decoding of motion vector difference in for inter-predicting a video block. An example is disclosed for decoding an inter-predicted video block of a video stream. The method includes deriving an inter-prediction mode for the video block from the video stream; deriving a motion vector prediction mode for the video block; deriving, from the video stream, a context for signaling a set of syntax elements associated with a Motion Vector Difference (MVD) associated with the video block based on the inter-prediction mode and/or the motion vector prediction mode; and decoding the video block based on the set of syntax elements and the derived context.

Abstract: A video decoding apparatus includes a first buffer storing input data received from an entropy decoder, a first motion compensation processor extracting motion compensation reference data based on the input data, and store the motion compensation reference data in a pixel cache, a second buffer, and a controller. The input data comprises one of first data including motion information and second data including intra prediction information. The controller controls the second buffer to store the motion compensation reference data stored in the pixel cache when the input data is the first data, and controls the second buffer to store the second data stored in the first buffer when the input data is the second data.

Abstract: Embodiments of the present disclosure provide a solution for video processing. A method for video processing is proposed. The method comprises: determining, during a conversion between a target video block of a video and a bitstream of the video, at least one mapping relationship between a first set of values of a first color component and a second set of values of a second color component; determining a cross-component prediction of the target video block based on the at least one mapping relationship; and performing the conversion based on the cross-component prediction.

Abstract: A method and an apparatus are disclosed for video coding using a candidate list of motion vector predictors. The video coding method and the apparatus compose a candidate list that further includes object corresponding position candidates and large motion candidates. The video coding method and the apparatus reconstruct a motion vector of the current block based on the candidate list.

Abstract: A video decoding apparatus is a video decoding apparatus for deriving a prediction image by using a reference picture included in a reference picture list.