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 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: An encoding control method includes obtaining a current to-be-processed node in a target queue, where the target queue includes nodes whose corresponding space blocks are occupied in a constructed tree structure; obtaining a first mode identifier of the current to-be-processed node; and in a case that the first mode identifier is a first identifier, if nodes that have been processed continuously meet a first condition, performing multiway tree occupancy encoding on the current to-be-processed node; where the first condition includes that: a mode identifier of the node that has been processed continuously is the first identifier and a number of nodes that have been processed continuously is less than a first threshold.

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 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 point cloud attribute information encoding method includes: obtaining first information; determining, based on second information associated with the first information, whether to perform DCT transform on K to-be-coded points; in a case that it is determined to perform DCT transform on the K to-be-coded points, performing DCT transform on the K to-be-coded points to obtain a transform coefficient of the K to-be-coded points; and quantizing the transform coefficient of the K to-be-coded points and performing entropy coding based on a quantized transform coefficient, to generate a binary bit stream. The first information includes the K to-be-coded points and the second information includes attribute prediction information for the K to-be-coded points; or the first information includes N coded points prior to the K to-be-coded points and the second information includes attribute reconstruction information for the N coded points.

Abstract: Disclosed are a point cloud encoding and decoding method and device based on a two-dimensional regularization plane projection. The encoding method includes: acquiring original point cloud data; performing two-dimensional regularization plane projection on the original point cloud data to obtain a two-dimensional projection plane structure; obtaining a plurality of pieces of two-dimensional image information according to the two-dimensional projection plane structure; and encoding the plurality of pieces of two-dimensional image information to obtain code stream information.

Abstract: A point cloud encoding processing method includes obtaining a current to-be-encoded node in a target queue, where the target queue includes an occupied node in a space block corresponding to a constructed tree structure based on first geometric information, the first geometric information is obtained by preprocessing based on geometric information of a to-be-encoded N-th frame point cloud, and N is an integer greater than 1; and determining an encoding mode of the current to-be-encoded node based on whether the current to-be-encoded node meets an encoding condition of an isolated point. The encoding condition of the isolated point includes an occupancy status of a target node meets a preset condition. The target node is a node that is in encoded nodes and that is associated with the current to-be-encoded node.

Abstract: The present invention discloses a method and an apparatus for 2D regularized planar projection of a point cloud. The method includes: obtaining original point cloud data; initializing a planar structure of 2D projection of the point cloud; calculating horizontal azimuth information of the point cloud based on the original point cloud data; and determining a mapping relationship between the original point cloud data and the planar structure of 2D projection based on the horizontal azimuth information, to obtain a planar structure of 2D regularized projection of the point cloud. In the present invention, a large-scale point cloud may be projected to a 2D regularized planar structure without 2D local search. Therefore, complexity of an algorithm can be reduced, time spent on 2D regularized planar projection of the point cloud can be reduced, and algorithm performance can be improved.

Abstract: Methods for determining a prediction value, an encoder, and a decoder are provided. Reconstructed values of neighboring samples of a current block are acquired, and then filtered to obtain a reference value set of the current block. When a size of the current block is smaller than a preset threshold value, a first constant value is calculated according to a bit depth value of a luma component of a sample in the current block. A difference between the first constant value and a first reference value in the reference value set is determined as a first prediction input value in a prediction input value set. Other prediction input values in the prediction input value set other than the first prediction input value are determined according to the reference value set. Prediction values of samples at specific positions in the current block is calculated and then filtered.

Abstract: An image decoding method, a decoder and a storage medium are provided. The method includes: receiving code stream data, and parsing the code stream data to obtain a coding tree unit corresponding to the code stream data; parsing an i-th node of i-th layer corresponding to the coding tree unit to obtain i-th state parameter and i-th flag parameter corresponding to the i-th node; performing detection processing on the i-th node according to the i-th state parameter and the i-th flag parameter to obtain an i-th detection result; acquiring a (i+1)th node of a (i+1)th layer corresponding to the coding tree unit; continuing to perform detection processing on the (i+1)th node, and traversing all the nodes corresponding to the coding tree unit until all the coding unit data corresponding to the coding tree unit is obtained; and generating a decoded image corresponding to the code stream data.

Abstract: This application discloses an entropy encoding method and apparatus, and an entropy decoding method and apparatus. The entropy encoding method in the embodiments of this application includes: obtaining, by an entropy encoding apparatus, sparsity/density information of a to-be-encoded target point cloud; determining, based on the sparsity/density information, a type of an occupancy code context model used to perform entropy encoding on the target point cloud; and performing entropy encoding on the target point cloud based on the type of the occupancy code context model.

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; determines a first prediction value of the current block according to the second offset; and determines a reconstructed value of the current block based on the first prediction value.

Abstract: Chroma intra prediction methods and devices are provided. The method comprises parsing bitstream data corresponding to a current chroma block, and determining that a prediction mode corresponding to the current chroma block is DM; before determining a set of chroma prediction modes based on at least one modified candidate mode, acquiring a linear mode corresponding to the current chroma block; determining an intra prediction mode of the current chroma block from the set of chroma prediction modes, wherein the set of chroma prediction modes comprises at least one of the DM, LM, LM_T or LM_L, wherein when a luma prediction mode corresponding to the DM is one of a DC mode, Planar mode, VER mode or HOR mode, the set of modes comprises an angular mode with an index number 66; and determining a reconstructed value of the current chroma block according to the intra prediction mode.

Abstract: Chroma intra prediction methods and devices are provided. The method comprising: parsing bitstream data corresponding to a current chroma block, and determining that a prediction mode corresponding to the current chroma block is DM; before determining a set of chroma prediction modes based on at least one modified candidate mode, acquiring a linear mode corresponding to the current chroma block from the bitstream data; determining an intra prediction mode of the current chroma block from the set of chroma prediction modes, wherein the set of chroma prediction modes comprises at least one of the DM, LM, LM_T or LM_L, wherein when a luma prediction mode corresponding to the DM is a DC mode or a planar mode, the set of chroma prediction modes comprises a diagonal angular mode with prediction direction index number 66, determining a reconstructed value of the current chroma block according to the intra prediction mode.

Abstract: A prediction method, an encoder, a decoder, and a computer storage medium are provided. The prediction method applied to an encoder includes: determining a spatial block in which an encoding point is located; constructing a prediction model according to the spatial block; acquiring a value of a first colour component and a value of a second colour component of the encoding point; obtaining a prediction value of the second colour component of the encoding point by using the prediction model and the value of the first colour component; calculating a difference between the value of the second colour component and the prediction value of the second colour component, and using the obtained difference as a residual of the encoding point; and performing Level of Detail (LOD) partitioning and lifting transform based on the residual of the encoding point.

Abstract: A method for intra prediction includes: enabling intra prediction, and determining occupancy information of a first number of neighboring nodes of a coded node; determining occupancy information of a second number of neighboring nodes of the coded node based on a position association between at least one neighboring node of the coded node and a child node of the coded node, where the first number is greater than the second number; and determining an occupancy prediction result of the child node of the coded node based on the occupancy information of the second number of neighboring nodes. An encoder for implementing the above method is also provided.

Abstract: This application discloses a point cloud encoding processing method and apparatus and a point cloud decoding processing method and apparatus. The point cloud encoding processing method of embodiments of this application includes: determining sparsity level information of a target point cloud; and in a case that the sparsity level information indicates the target point cloud being a sparse point cloud and a node to be encoded corresponding to the target point cloud satisfies an isolated point encoding condition, enabling an isolated point encoding mode.

Abstract: An image decoding method, a decoder and a storage medium are provided. The method includes: receiving code stream data, and parsing the code stream data to obtain a coding tree unit corresponding to the code stream data; parsing an i-th node of i-th layer corresponding to the coding tree unit to obtain i-th state parameter and i-th flag parameter corresponding to the i-th node; performing detection processing on the i-th node according to the i-th state parameter and the i-th flag parameter to obtain an i-th detection result; acquiring a (i+1)th node of a (i+1)th layer corresponding to the coding tree unit; continuing to perform detection processing on the (i+1)th node, and traversing all the nodes corresponding to the coding tree unit until all the coding unit data corresponding to the coding tree unit is obtained; and generating a decoded image corresponding to the code stream data.

Abstract: Disclosed are a point cloud encoding and decoding method and device based on a two-dimensional regularization plane projection. The encoding method includes: acquiring original point cloud data; performing two-dimensional regularization plane projection on the original point cloud data to obtain a two-dimensional projection plane structure; obtaining a plurality of pieces of two-dimensional image information according to the two-dimensional projection plane structure; and encoding the plurality of pieces of two-dimensional image information to obtain code stream information.