Abstract: Disclosed in the implementations of the present disclosure are a mapping method, an encoder, a decoder, and a computer storage medium. The method may include: determining an intra prediction mode used at the time of encoding or decoding a current block; mapping, if the intra prediction mode is a MIP mode, the MIP mode to a first non-MIP mode; and mapping, if the intra prediction mode is a non-MIP mode, the non-MIP mode to a second MIP mode.

Abstract: A prediction method for decoding and apparatus, and a computer storage medium are provided. 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 a picture encoding and decoding method, an encoder, a decoder and a storage medium. The decoder decodes a bitstream to obtain a size, a coding mode, and residuals of a current block; when the coding mode of the current block is an MIP mode, calculates a second offset based on the size of the current block, a first offset and reconstructed values of adjacent pixels corresponding to the current block; calculates a second prediction value of a pixel at a preset position in the current block by using the second offset, the preset position being a particular position in the current block; performs filtering on the second prediction value to obtain first prediction values of all pixels in the current block; and calculates sum values of the first prediction values and the residuals, and sets the sum values as reconstructed values of the current block.

Abstract: Picture coding and decoding methods, an encoder, a decoder and a storage medium are provided. The encoder, before performing coding processing according to a matrix-based intra prediction (MIP) mode, sets initial right shift parameters corresponding to different sizes and different MIP mode numbers as an uniform offset parameter, the offset parameter indicating a number of right shifting bits of a predicted value, and when performing coding processing according to the MIP mode, performs coding processing according to the offset parameter. The decoder, before performing decoding processing according to an MIP mode, sets initial right shift parameters corresponding to different sizes and different MIP mode numbers as an uniform offset parameter, the offset parameter indicating a number of right shifting bits of a predicted value, and when performing decoding processing according to the MIP mode, performs decoding processing according to the offset parameter.

Abstract: A method for colour component prediction, an encoder, a decoder and a storage medium are provided. The method includes that: prediction parameters of a current block are determined, the prediction parameters including a prediction mode parameter and a size parameter of the current block; when the prediction mode parameter indicates that a Matrix-based Intra Prediction (MIP) mode is adopted to determine an intra prediction value of the current block, an MIP weight matrix of the current block, a shift factor of the current block and an MIP input sample matrix of the current block are determined; and the intra prediction value of the current block is determined according to the MIP weight matrix, the shift factor and the MIP input sample matrix.

Abstract: A video colour component prediction method and apparatus, and a computer storage medium are provided. The prediction method includes: obtaining a first colour component neighboring reference value and a first colour component reconstructed value corresponding to a current coding block, wherein the first colour component neighboring reference value represents a first colour component parameter corresponding to a neighboring reference sample of the current coding block, and the first colour component reconstructed value represents one or more reconstruction parameters of a first colour component corresponding to the current coding block; determining a weight coefficient corresponding to the neighboring reference sample; determining a scale factor according to the weight coefficient and the first colour component neighboring reference value; and obtaining a second colour component predicted value corresponding to the current coded block based on a linear model corresponding to the scale factor.

Abstract: A method and device for predicting colour component and a computer storage medium are provided. The method includes: acquiring at least one threshold value according to first colour component reconstructed values of all samples of a current coding block; performing grouping according to comparison results between a first colour component neighboring reference values of current coding block and the at least one threshold value to obtain at least two groups of first colour component neighboring reference values and second colour component neighboring reference values; establishing at least two computing models; selecting, according to comparison results between the first colour component reconstructed values and at least one threshold value, a computing model corresponding to each sample in current coding block from at least two computing models; and acquiring, according to the computing model corresponding to each sample, second colour component prediction values of all samples in the current coding block.

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.