Abstract: Disclosed are a colour component prediction method, an encoder, a decoder, and a storage medium. The method includes: determining adjacent reference pixels of a current block in a picture; constructing a subset of adjacent reference pixels according to the adjacent reference pixels, wherein the subset of adjacent reference pixels contains a part of the adjacent reference pixels; and calculating model parameters of a prediction model according to the subset of adjacent reference pixels, wherein the prediction model includes N prediction sub-models, the N prediction sub-models correspond to N groups of model parameters, and the prediction sub-models are used to perform, through corresponding model parameters, cross-component prediction of colour components to be predicted, and N is a positive integer greater than or equal to 2.

Abstract: Colour component prediction method is provided, which includes that: first reference sample set corresponding to colour component to be predicted of coding block in video image is acquired; when available sample number in first reference sample set is less than preset number, preset component value is taken as predicted value corresponding to the colour component to be predicted; when available sample number in first reference sample set is not less than preset number, first reference sample set is screened to obtain second reference sample set; when available sample number in second reference sample set is equal to preset number, model parameter is determined through second reference sample set, and prediction model corresponding to colour component to be predicted is obtained based on model parameter, prediction model is used for prediction processing of colour component to be predicted to obtain predicted value corresponding to colour component to be predicted.

Abstract: A prediction method, apparatus, and a computer storage medium for decoding, the method includes: acquiring reference samples adjacent to at least one side of a decoding block; determining a reference point from the at least one side and determining reference sample positions to be selected corresponding to the at least one side according to a preset number of samples; selecting reference samples corresponding to the reference sample positions to be selected from the reference samples based on the reference sample positions to be selected; and performing prediction decoding on the decoding block based on the selected reference samples.

Abstract: A prediction method, apparatus, and a computer storage medium for decoding, the method includes: acquiring reference samples adjacent to at least one side of a decoding block; determining a reference point from the at least one side and determining reference sample positions to be selected corresponding to the at least one side according to a preset number of samples; selecting reference samples corresponding to the reference sample positions to be selected from the reference samples based on the reference sample positions to be selected; and performing prediction decoding on the decoding block based on the selected reference samples.

Abstract: A prediction method, apparatus, and a computer storage medium for decoding, the method includes: acquiring reference samples adjacent to at least one side of a decoding block; determining a reference point from the at least one side and determining reference sample positions to be selected corresponding to the at least one side according to a preset number of samples; selecting reference samples corresponding to the reference sample positions to be selected from the reference samples based on the reference sample positions to be selected; and performing prediction decoding on the decoding block based on the selected reference samples.

Abstract: A prediction method, apparatus, and a computer storage medium for decoding, the method includes: acquiring reference samples adjacent to at least one side of a decoding block; determining a reference point from the at least one side and determining reference sample positions to be selected corresponding to the at least one side according to a preset number of samples; selecting reference samples corresponding to the reference sample positions to be selected from the reference samples based on the reference sample positions to be selected; and performing prediction decoding on the decoding block based on the selected reference samples.

Abstract: Provided are an intra prediction method and apparatus, and a computer-readable storage medium. The method includes: acquiring a first reference sample set corresponding to the current processing block, wherein the first reference sample set includes at least one of a reference row adjacent to the current processing block and a reference column adjacent to the current processing block; selecting, based on a pre-set selection method, a second reference sample set from the first reference sample set, wherein the second reference sample set includes at least one reference sample in the reference row adjacent to the current processing block or the reference column adjacent to the current processing block; obtaining, based on the second reference sample set, a prediction value of the current processing block; and performing, based on the prediction value, intra prediction on the current processing block.

Abstract: A method for determining a prediction direction is provided. The method is implemented by a decoder. The method includes: acquiring a Direct Mode (DM) in a chroma intra prediction mode of a block to be decoded (S101); and determining an index number of a prediction direction in a DM derived mode based on an offset N and an index number M of a prediction direction in the DM to determine the DM derived mode (S102).

Abstract: The present invention discloses a preparation method for a surface molding film of a PVC-based stone plastic composite board, including: surface activation treatment of the PVC-based stone plastic composite board: preparation of an activated putty, coarse roughening of a substrate surface, application and solidification of the activated putty, and fine roughening of the substrate surface; preparation of a PMMA slurry; and surface film forming of the PVC-based stone plastic composite board. The PVC-based stone plastic composite board coated with a PMMA film is obtained by cold pressing and shaping in a mold, tightening up a clamp, solidifying at low temperature, treating at high temperature, cooling and demolding.

Abstract: An intra prediction method and device and a computer-readable storage medium, the method comprising: configuring actual angle modes indicated by relative angle numbers, wherein the relative angle numbers are successively represented within a prediction direction range corresponding to a preset width and height relationship; starting from a starting angle, using a corresponding actual angle mode after sampling preset angle sample points, said starting angle being determined according to the width and height relationship of processing blocks and the prediction direction range corresponding to the preset width and height relationship, and actual angles having a one-to-one correspondence with the actual angle modes.

Abstract: A method for decoding a picture, a method for encoding a picture, an encoder, and a decoder are provided. The method for encoding a picture includes (i) determining a width and a height of a coding block in the picture; (ii) if the width and the height are equal to N, where N is a positive integer power of 2, determining a matrix-based intra prediction (MIP) size identifier indicating that an MIP prediction size equal to N; (iii) deriving a group of reference samples of the coding block; and (iv) deriving an MIP prediction of the coding block based on the group of reference samples and an MIP matrix corresponding to the MIP size identifier.

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: The implementation of the present disclosure provides a point cloud partitioning method and device, and a computer-readable storage medium, including: when performing stripe division along the longest side, adjusting an initial partitioning position or determining the stripe division length according to the size of a preset block, to obtain a stripe division position, wherein, the length of the first n-1 stripes along the longest side is an integer multiple of the side length of the preset block, n is the number of divided stripes, and n is a positive integer greater than or equal to 2.

Abstract: A point cloud model reconstruction method, an encoder, and a decoder are provided. The method includes the following. An i-th segmentation position of an i-th three-dimensional slice on a longest edge in a point cloud space is obtained, where 1?i?n?1 and n is a total number of three-dimensional slices to-be-processed. An i-th cube block set nearest to the i-th segmentation position in the i-th three-dimensional slice is determined based on the i-th segmentation position and a preset cube block length. An i-th vertex position with a cube block in the i-th cube block set is determined along the longest edge, where the i-th vertex position represents a position of a vertex on an edge which is away from a start position of the cube block by the preset cube block length. A point cloud model is reconstructed based on the i-th vertex position.

Abstract: A method for picture decoding, a method for picture encoding, a decoder, and an encoder are provided. The method includes the following. A bitstream corresponding to a current picture is acquired. The bitstream is parsed to obtain a flag corresponding to the current picture. A cross-decoding function is disabled when a decoding manner indicated by the flag is independent decoding of colour components, where the cross-decoding function allows decoding based on a dependency relationship between two chroma components.

Abstract: A point cloud encoding and decoding method, an encoder, and a decoder are provided. The encoder determines a processing order of point cloud data during point cloud encoding. The encoder determines a coordinate-axis-order index corresponding to the processing order. The encoder encodes the coordinate-axis-order index and signals encoded bits into a bitstream. The encoder processes the point cloud data according to the processing order, to obtain point cloud data to-be-encoded. The encoder encodes the point cloud data to-be-encoded and signals encoded bits into the bitstream. The decoder parses a bitstream to obtain a coordinate-axis-order index, determines a processing order of point cloud data during point cloud decoding according to the coordinate-axis-order index, parses the bitstream to obtain recovered data of the point cloud data, and determines a position of coordinate data of the point cloud data in a storage unit of the recovered data according to the processing order.

Abstract: Disclosed are a colour component prediction method, encoder, decoder, and storage medium. When CCLM is used for a current block to determine its intra prediction value, the encoder determines multiple groups of corresponding CCLM parameters using multiple groups of reference samples of current block, determines a target CCLM parameter from multiple groups of CCLM parameters; sets a CCLM index value indicating to use the target CCLM parameter and signals same in bitstream; and determines intra prediction value of current block according to the target CCLM parameter. The decoder parses bitstream to determine a prediction mode parameter of current block, parses bitstream to determine a CCLM index value of current block when prediction mode parameter indicates intra prediction value of current block is determined using CCLM; determines target CCLM parameter according to the CCLM index value, and determines intra prediction value of current block according to the target CCLM parameter.

Abstract: An information processing method and device, an apparatus, and a storage medium. The method includes: for inputted source video data, predicting a colour component of a coding block in the source video data according to a prediction mode to obtain a first prediction block, wherein the prediction mode is preset and is a Position-Dependent Prediction Combination (PDCP) mode; determining a difference between the colour component of the coding block and a prediction value of the first prediction block to obtain a residual block; and signalling the residual block and the prediction mode in a bitstream.

Abstract: A prediction method, apparatus, and a computer storage medium for decoding, the method includes: acquiring reference samples adjacent to at least one side of a decoding block; determining a reference point from the at least one side and determining reference sample positions to be selected corresponding to the at least one side according to a preset number of samples; selecting reference samples corresponding to the reference sample positions to be selected from the reference samples based on the reference sample positions to be selected; and performing prediction decoding on the decoding block based on the selected reference samples.

Abstract: Processing methods for motion compensation, an encoder, and a decoder are provided. The method includes the following. Determine a search position constellation with a point pointed by an initial motion vector as a center point, where the search position constellation includes N directions, search for at least one search point by using at least one type of step lengths in the directions, where the at least one search point at least includes at least one search point in diagonal directions. Search for at least one search position from the search position constellation based on a preset range coverage rule, where the preset range coverage rule is to arrange search points in the directions for search. Obtain a new motion vector according to the at least one search position, and perform motion compensation based on the new motion vector to obtain a prediction value of a coding unit (CU).