Abstract: An inter-frame prediction method and apparatus, and related devices and a storage medium. The method comprises: determining a first motion vector and a second motion vector of a current block, wherein the first motion vector is a forward motion vector of the current block, and the second motion vector is a backward motion vector of the current block; on the basis of the first motion vector and the second motion vector, determining whether a set condition is satisfied, and obtaining a determination result; setting the value of a BDOF flag according to the determination result; and determining, on the basis of the value of the BDOF flag, an inter-frame prediction value of the current block or at least one sub-block in the current block.

Abstract: A method for colour component prediction comprising: determining a neighbouring reference sample set of a current block, and determining a preset parameter value corresponding to the current block, wherein the neighbouring reference sample set comprises at least one reference sample; caching the neighbouring reference sample set and the preset parameter value to create an input reference sample set; determining an input sample matrix using a first preset calculation model according to the reference sample set; and performing colour component prediction on the current block according to the input sample matrix to obtain a prediction block of the current block.

Abstract: Disclosed are a transformation method, an encoder, a decoder, and a storage medium. The transformation method applied to an encoder includes: determining a prediction mode parameter of a current block; determining a Matrix-based Intra Prediction (MIP) parameter when the prediction mode parameter indicates that MIP is used for the current block to determine an intra prediction value; determining an intra prediction value of the current block according to the MIP parameter and calculating a residual value between the current block and the intra prediction value; determining a Low-Frequency Non-Separable Transform (LFNST) transform kernel used for the current block according to the MIP parameter when an LFNST is used for the current block, setting an LFNST index, and signalling the LFNST index in a video bitstream; and performing a transform processing on the residual value by using the LFNST transform kernel.

Abstract: A transform method and a decoder. The encoder determines a prediction mode parameter of a current block; determines a cross-component linear model (CCLM) parameter when the prediction mode parameter indicates that CCLM prediction is used for the current block to determine an intra prediction value; determines the intra prediction value of the current block according to the CCLM parameter, and calculates a residual value between the current block and the intra prediction value; determines a low-frequency non-separable transform (LFNST) transform kernel used for the current block according to the CCLM parameter, sets an LFNST index, and signals the LFNST index into a bitstream of a video, when LFNST is used for the current block; and transforms the residual value with the LFNST transform kernel.

Abstract: Described is a nearest neighbor search method. The method is applicable in a device and comprises: acquiring a Morton code set of point cloud data to be searched; stratifying the point cloud data on the basis of the Morton code set and of a first distance threshold to produce current stratum data; shifting to the right by a first preset digit Morton codes of prediction data other than the stratified data in the point cloud data to produce a corresponding first parent node set; determining, on the basis of Morton codes of the current stratum data, a neighbor area satisfying a criterion in the first parent node set; and determining a nearest neighboring point set of the current stratum data in the neighboring area. Also provided in an exemplary embodiment of the present application are a device and a computer storage medium.

Abstract: A transform method includes: determining a prediction mode parameter of a current block; determining a MIP parameter when the prediction mode parameter indicates that MIP is used for the current block to determine an intra prediction value; determining the intra prediction value of the current block according to the MIP parameter, and calculating a residual value between the current block and the intra prediction value; performing a first transform on the residual value to obtain a first coefficient matrix; determining a scanning order of LFNST coefficients used for the current block according to the MIP parameter when an LFNST is used for the current block; constructing an input coefficient matrix of the LFNST based on the first coefficient matrix according to the scanning order of LFNST coefficients; and performing an LFNST processing on the input coefficient matrix to obtain a transform coefficient matrix of the current block.

Abstract: A transform method applied to an encoder includes: determining a prediction mode parameter of a current block; determining a CCLM parameter when the prediction mode parameter indicates that CCLM is used for the current block to determine an intra prediction value; determining the intra prediction value of the current block according to the CCLM parameter and calculating a residual value between the current block and the intra prediction value; performing a first transform on the residual value to obtain a first coefficient matrix; determining an LFNST coefficient scanning order used for the current block according to the CCLM parameter when an LFNST is used for the current block; constructing an input coefficient matrix of the LFNST by using the first coefficient matrix according to the LFNST coefficient scanning order; and performing an LFNST processing on the input coefficient matrix to obtain a transform coefficient matrix of the current block.

Abstract: Provided by the implementations of the present disclosure are a transform method, a coder, a decoder and a computer readable storage medium. The transform method includes: determining normal vectors of encoding points in an encoding point cloud; analyzing the sum total of all coordinates of the normal vectors on the basis of the normal vectors of the encoding points; and determining a transform sequence on the basis of the sum total of all coordinates of the normal vectors.

Abstract: A method for intra prediction includes: obtaining multiple previously reconstructed neighbouring blocks corresponding to a current processing block; determining prediction modes, that are signalled in a bitstream, corresponding to neighbouring blocks of the multiple previously reconstructed neighbouring blocks, to obtain multiple first prediction modes; if the multiple first prediction modes comprise at least two directional modes, taking directional modes comprised in the multiple first prediction modes as first prediction directions; performing, according to a preset operation rule, operation on multiple first prediction directions of the first prediction directions to obtain second prediction directions; obtaining a prediction mode set according to the second prediction directions and the multiple first prediction modes; and performing intra prediction on the current processing block based on the prediction mode set.

Abstract: A chroma intra prediction method and device are provided. The method applied to a decoder includes parsing bitstream data corresponding to a current chroma block, and determining that a prediction mode corresponding to the current chroma block is a direct mode (DM); determining an intra prediction mode of the current chroma block from a set of chroma prediction modes, wherein the set of chroma prediction modes comprises at least one of DM, LM, LM_T or LM_L; and determining a reconstructed value of the current chroma block according to the intra prediction mode.

Abstract: Provided is a method for predicting attribute information, a coder, a decoder, and a storage medium. The coder determines a current Morton code corresponding to a point to be predicted in a point cloud to be coded, determines a target Morton code corresponding to the point to be predicted based on the current Morton code and according to a preset neighbor information table, judges whether a neighbor point of the point to be predicted exists in the point cloud to be coded according to the target Morton code, and performs prediction to obtain a predicted attribute value of the point to be predicted according to attribute reconstruction information of the neighbor point in response to that the neighbor point exists in the point cloud to be coded.

Abstract: Provided are a point cloud processing method, an encoder and a decoder.

Abstract: A media information processing method includes obtaining media description information, where the media description information includes description information of at least two bitstreams corresponding to a first picture area, any one of the at least two bitstreams has an access point different in time from an access point of another bitstream in the at least two bitstreams, the at least two bitstreams are bitstreams obtained by separately encoding picture content of the first picture subarea, and time periods corresponding to the picture content separately encoded by the at least two bitstreams overlap, and determining, based on the media description information, a to-be-played first target bitstream, where the first target bitstream is one of the at least two bitstreams.

Abstract: A prediction decoding method, a prediction decoding apparatus, and a non-transitory computer storage medium are provided. The method includes the following. First multiple neighbouring reference samples of a coding block are determined, where the first multiple neighbouring reference samples include reference samples in a reference row or a reference column neighbouring the coding block. Positions corresponding to K reference samples are determined from a starting position of the reference row or the reference column, where K is a positive integer. Second multiple neighbouring reference samples are determined according to the determined positions corresponding to the K reference samples, where the second multiple neighbouring reference samples include neighbouring reference samples among the first multiple neighbouring reference samples. Prediction decoding is performed on the coding block according to the second multiple neighbouring reference samples.

Abstract: A prediction decoding method, a prediction decoding apparatus, and a non-transitory computer storage medium are provided. The method includes the following. First multiple neighbouring reference samples of a coding block are determined, where the first multiple neighbouring reference samples include reference samples in a reference row or a reference column neighbouring the coding block. Positions corresponding to K reference samples are determined from a starting position of the reference row or the reference column, where K is a positive integer. Second multiple neighbouring reference samples are determined according to the determined positions corresponding to the K reference samples, where the second multiple neighbouring reference samples include neighbouring reference samples among the first multiple neighbouring reference samples. Prediction decoding is performed on the coding block according to the second multiple neighbouring reference samples.

Abstract: A prediction decoding method, a prediction decoding apparatus, and a non-transitory computer storage medium are provided. The method includes the following. First multiple neighbouring reference samples of a coding block are determined, where the first multiple neighbouring reference samples include reference samples in a reference row or a reference column neighbouring the coding block. Positions corresponding to K reference samples are determined from a starting position of the reference row or the reference column, where K is a positive integer. Second multiple neighbouring reference samples are determined according to the determined positions corresponding to the K reference samples, where the second multiple neighbouring reference samples include neighbouring reference samples among the first multiple neighbouring reference samples. Prediction decoding is performed on the coding block according to the second multiple neighbouring reference samples.

Abstract: A prediction decoding method, a prediction decoding apparatus, and a non-transitory computer storage medium are provided. The method includes the following. First multiple neighbouring reference samples of a coding block are determined, where the first multiple neighbouring reference samples include reference samples in a reference row or a reference column neighbouring the coding block. Positions corresponding to K reference samples are determined from a starting position of the reference row or the reference column, where K is a positive integer. Second multiple neighbouring reference samples are determined according to the determined positions corresponding to the K reference samples, where the second multiple neighbouring reference samples include neighbouring reference samples among the first multiple neighbouring reference samples. Prediction decoding is performed on the coding block according to the second multiple neighbouring reference samples.

Abstract: A prediction decoding method, a prediction decoding apparatus, and a computer storage medium are provided. The method includes the following. First multiple neighbouring reference samples are obtained by acquiring neighbouring reference samples of a coding block, where the first multiple neighbouring reference samples include reference samples in a reference row or a reference column neighbouring the coding block. Positions corresponding to K reference samples are determined from a starting position of the reference row or the reference column, where K is a positive integer. Second multiple neighbouring reference samples are obtained according to the determined positions corresponding to the K reference samples, where the second multiple neighbouring reference samples include neighbouring reference samples among the first multiple neighbouring reference samples except the K reference samples. Prediction decoding is performed on the coding block according to the second multiple neighbouring reference samples.

Abstract: Provided by the implementations of the present disclosure are a transform method, a coder, a decoder and a computer readable storage medium. The transform method includes: determining normal vectors of encoding points in an encoding point cloud; analyzing the sum total of all coordinates of the normal vectors on the basis of the normal vectors of the encoding points; and determining a transform sequence on the basis of the sum total of all coordinates of the normal vectors.

Abstract: A method for intra prediction includes: obtaining multiple previously reconstructed neighbouring blocks corresponding to a current processing block; determining prediction modes, that are signalled in a bitstream, corresponding to neighbouring blocks of the multiple previously reconstructed neighbouring blocks, to obtain multiple first prediction modes; if the multiple first prediction modes comprise at least two directional modes, taking directional modes comprised in the multiple first prediction modes as first prediction directions; performing, according to a preset operation rule, operation on multiple first prediction directions of the first prediction directions to obtain second prediction directions; obtaining a prediction mode set according to the second prediction directions and the multiple first prediction modes: and performing intra prediction on the current processing block based on the prediction mode set.