Three-dimensional grid coding and decoding method and device thereof

Abstract

The invention discloses a three-dimensional grid coding and decoding method and device, and relates to the technical field of coding and decoding, and the method comprises the steps: obtaining a reference grid and dividing the reference grid, and dividing the reference grid into at least one sub-reference grid according to the reference grid division; obtaining a to-be-coded grid and to-be-coded grid division, and dividing the to-be-coded grid into at least one sub-to-be-coded grid according to the to-be-coded grid division; and determining whether the sub-to-be-coded grids are coded by using the information of all or part of the sub-reference grids. According to the invention, a more accurate coding and decoding method can be provided.

Description

Technical Field

[0001] The present invention relates to the field of coding and decoding technology, and in particular to a three-dimensional grid coding and decoding method and a device thereof. Background Art

[0002] In recent years, with the rapid development of multimedia technology, related research results have been rapidly industrialized and have become an indispensable part of people's lives. Three-dimensional models have become a new generation of digital media after audio, images, and videos. Three-dimensional grids are a commonly used way to represent three-dimensional models. Compared with traditional multimedia such as images and videos, three-dimensional grid models have stronger interactivity and realism, making them more and more widely used in various fields such as commerce, manufacturing, construction, education, medicine, entertainment, art, and military.

[0003] In the related technologies, as people have higher and higher demands for the visual effects of three-dimensional mesh models, the models have become more and more complex, and the accuracy of the models has also become higher and higher, which has caused the amount of data required to represent the three-dimensional mesh to increase accordingly; the above problems have caused the processing, visualization, transmission and storage of three-dimensional meshes to become more and more complicated.

[0004] Therefore, there is an urgent need to improve the defects in the prior art. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a three-dimensional grid encoding and decoding method and device thereof. The technical problem to be solved by the present invention is achieved by the following technical solutions:

[0006] In a first aspect, the present invention provides a three-dimensional grid coding method, comprising:

[0007] Obtaining a reference grid and a reference grid division, and dividing the reference grid into at least one sub-reference grid according to the reference grid division;

[0008] Obtaining a grid to be encoded and a grid division to be encoded, and dividing the grid to be encoded into at least one sub-grid to be encoded according to the grid division to be encoded;

[0009] Determine whether the sub-grid to be encoded is encoded using all or part of the information of the sub-reference grid.

[0010] In a second aspect, the present invention further provides a three-dimensional grid decoding method, comprising:

[0011] Obtaining a reference grid and a reference grid division, and dividing the reference grid into at least one sub-reference grid according to the reference grid division;

[0012] Obtaining a to-be-decoded grid and a to-be-decoded grid division, and dividing the to-be-decoded grid into at least one sub-to-be-decoded grid according to the to-be-decoded grid division;

[0013] Determine whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding.

[0014] In a third aspect, the present invention further provides a three-dimensional grid encoding device, comprising:

[0015] A first acquisition unit is used to acquire a reference grid and a reference grid division, and divide the reference grid into at least one sub-reference grid according to the reference grid division;

[0016] A second acquisition unit is used to acquire a to-be-coded grid and a to-be-coded grid division, and divide the to-be-coded grid into at least one sub-to-be-coded grid according to the to-be-coded grid division;

[0017] The determination unit is used to determine whether the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding.

[0018] In a fourth aspect, the present invention further provides a three-dimensional grid decoding device, comprising:

[0019] A first acquisition unit is used to acquire a reference grid and a reference grid division, and divide the reference grid into at least one sub-reference grid according to the reference grid division;

[0020] A second acquisition unit is used to acquire a to-be-decoded grid and a to-be-decoded grid division, and divide the to-be-decoded grid into at least one sub-to-be-decoded grid according to the to-be-decoded grid division;

[0021] The determination unit is used to determine whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding.

[0022] Beneficial effects of the present invention:

[0023] The present invention provides a three-dimensional grid encoding and decoding method and device thereof, which improves the encoding process of the basic grid in the VDMC encoding process in the prior art; that is, according to the division of the grid to be encoded, the grid to be encoded is divided into at least one sub-grid to be encoded; according to the division of the reference grid, the reference grid is divided into at least one sub-reference grid; wherein, for each sub-grid to be encoded, an intra-frame coding mode or an inter-frame coding mode will be adopted. For the sub-grid to be encoded using the intra-frame coding mode, the information of the sub-reference grid is not used for encoding. For the sub-grid to be encoded using the inter-frame coding mode, the information of the sub-reference grid is used for encoding. For each sub-grid to be encoded using the inter-frame coding mode, a sub-reference grid uniquely corresponding to it will be determined in the reference frame, and the sub-grid to be encoded will be determined to be encoded using the information of the sub-reference grid. Furthermore, it is possible to further determine whether the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding; it can be understood that if the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding, the sub-grid to be encoded is divided into one type of sub-grid; if the sub-grid to be encoded does not use all or part of the information of the sub-reference grid for encoding, the sub-grid to be encoded is divided into another type of sub-grid; in this way, when encoding the basic grid, the basic grid is divided into different types of sub-grids, and different encoding methods are used to encode different types of sub-grids. This differentiated encoding method can improve the flexibility of encoding, especially in the inter-frame mode, the selection of the reference area is more flexible, the encoding efficiency is improved, and the encoding can be refined to improve the accuracy of encoding.

[0024] Furthermore, the decoding end decodes the code stream information of the basic grid obtained in the encoding process, and then reconstructs the basic grid; corresponding to the encoding process, the grid to be decoded is divided into at least one sub-grid to be decoded according to the division of the grid to be decoded; the reference grid is divided into at least one sub-reference grid according to the division of the reference grid; wherein, for each grid to be decoded, an intra-frame decoding mode or an inter-frame decoding mode will be adopted. The sub-grid to be decoded in the intra-frame decoding mode does not use the information of the sub-reference grid for decoding; the sub-grid to be decoded in the inter-frame decoding mode uses the information of the sub-reference grid for decoding. For each sub-grid to be decoded in the inter-frame decoding mode, there will be a sub-reference grid that uniquely corresponds to it, and the sub-grid to be decoded is determined to be decoded using the information of the sub-reference grid. Furthermore, it is possible to further determine whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding; it can be understood that, in the decoding process, if the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding, then according to a type of sub-grid corresponding to the sub-grid to be decoded, it is decoded using a corresponding decoding method; if the sub-grid to be decoded does not use all or part of the information of the sub-reference grid for decoding, then according to another type of sub-grid corresponding to the sub-grid to be decoded, it is decoded using a corresponding decoding method; in this way, according to the division of the sub-grids to be encoded in the encoding process, the corresponding decoding method is used in the decoding process to decode the sub-grid code stream to improve the flexibility of decoding, achieve refined decoding, and improve the accuracy of information transmission.

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1( a ) is a schematic diagram of V3C standard encoding in the prior art provided by an embodiment of the present invention;

[0027] FIG1( b ) is a schematic diagram of V3C standard decoding in the prior art provided by an embodiment of the present invention;

[0028] FIG. 2( a ) is a schematic diagram of VDMC encoding in the prior art provided by an embodiment of the present invention;

[0029] FIG2( b ) is a schematic diagram of VDMC decoding in the prior art provided by an embodiment of the present invention;

[0030] Figure 3 is a flow chart of a three-dimensional grid encoding method provided by an embodiment of the present invention;

[0031] Figure 4 is a schematic diagram of basic grid division provided by an embodiment of the present invention;

[0032] Figure 5is a schematic diagram of basic grid division provided by an embodiment of the present invention;

[0033] Figure 6 is a schematic diagram of basic grid division provided by an embodiment of the present invention;

[0034] Figure 7 is a flow chart of a three-dimensional grid decoding method provided by an embodiment of the present invention;

[0035] Figure 8 This is a schematic diagram of basic grid code stream decoding provided by an embodiment of the present invention;

[0036] Fig. 9 This is a schematic diagram of basic grid code stream decoding provided by an embodiment of the present invention;

[0037] Fig.10 This is a schematic diagram of basic grid code stream decoding provided by an embodiment of the present invention;

[0038] Fig.11 is a schematic diagram of a three-dimensional grid encoding device provided by an embodiment of the present invention;

[0039] Fig.12 It is a schematic diagram of a three-dimensional grid decoding device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The present invention is further described in detail below with reference to specific embodiments, but the embodiments of the present invention are not limited thereto.

[0041] In the related technology, a three-dimensional mesh can be regarded as composed of three basic elements: vertices, edges and faces. Among them, vertex is the most basic element in the mesh, and multiple vertices define a position in a three-dimensional space. Edge is a line segment connecting two vertices in the mesh. Faces can be regarded as polygons formed by closed paths of edges. For triangular meshes, each face is a triangle.

[0042] The information included in the mesh is usually divided into three categories: geometric information, connection information and attribute information; among them, geometric information refers to the position of each vertex of the mesh in three-dimensional space; connection information describes the association relationship between elements in the mesh, that is, the connection relationship between vertices; attribute information is optional, and attributes can be associated with corresponding mesh elements (such as vertex color, normal vector, etc. can be associated with mesh vertices), and mesh parameterization can be used to map the mesh from three-dimensional space to a two-dimensional plane area. The two-dimensional mapping can be used to represent high-resolution attribute information, such as texture, normal vector, etc.

[0043] In recent years, MPEG, an international standardization organization in the field of audio and video coding compression, has begun to develop a compression standard VDMC (Video-based dynamic mesh coding) for three-dimensional meshes. This standard is based on the existing V3C (Visual Volumetric Video-based Coding) standard. Among them, the V3C standard provides a general method for compressing three-dimensional models, which can be presented in the form of point clouds, meshes or panoramic videos.

[0044] Wherein, please refer to FIG. 1(a) and FIG. 1(b), FIG. 1(a) is a schematic diagram of V3C standard encoding in the prior art provided by an embodiment of the present invention, and FIG. 1(b) is a schematic diagram of V3C standard decoding in the prior art provided by an embodiment of the present invention; the V3C standard provides a method for encoding or decoding various three-dimensional media by video or image encoding technology. Specifically, the V3C standard converts the three-dimensional media content from a three-dimensional representation into multiple two-dimensional representations (called V3C components) by projection and other methods before encoding, and then encodes the two-dimensional representation using existing video or image encoding technology. The V3C components mainly include occupancy components, geometric components, and attribute components; wherein, the occupancy component can indicate which areas in the two-dimensional representation are associated with the data of the three-dimensional representation, the geometric component indicates information related to the position of the three-dimensional data in space, and the attribute component can provide attribute information corresponding to the vertex, such as material, texture, etc. In addition, the components also contain information on how to reconstruct a three-dimensional model through these components, which is called atlas information. The atlas information is used to associate all components, and additional information for reconstructing from two-dimensional to three-dimensional is also included in the atlas components; the atlas consists of multiple basic units, called patches, each of which represents an area in the available two-dimensional components and contains the information needed to project the area back to three-dimensional space.

[0045] Wherein, please refer to Figures 2(a) and 2(b). Figure 2(a) is a schematic diagram of VDMC encoding in the prior art provided by an embodiment of the present invention, and Figure 2(b) is a schematic diagram of VDMC decoding in the prior art provided by an embodiment of the present invention. VDMC is a standard established by MPEG for compressing three-dimensional meshes. Its main idea is to compress three-dimensional meshes by utilizing the existing V3C standard. Since there is connection information in the three-dimensional mesh that needs to be encoded, its specific encoding process is slightly different from V3C. It is necessary to expand the syntax, semantics and decoding operations of the V3C standard decoding end to support the decoding and reconstruction of the three-dimensional mesh. Figures 2(a) and 2(b) are the current encoding and decoding frameworks of VDMC.

[0046] The overall framework of the encoding end is shown in Figure 2(a). For the input mesh, it is simplified by the simplification module, and new texture coordinates are generated for the mesh through mesh parameterization. The parameterized mesh is subdivided and deformed, that is, new vertices are inserted on the mesh according to a specific subdivision method and the distances from the subdivided mesh vertices to the nearest neighbor points of the input mesh are calculated, which is called displacement information. The parameterized mesh, that is, the vertex positions of the mesh before subdivision and deformation are adjusted according to the displacement information, and the adjusted mesh is called the base mesh and sent to the base mesh encoding module for compression. The base mesh is reconstructed after encoding, and then the order of displacement is adjusted according to the vertex order of the reconstructed base mesh. The vertex displacement information after the order is adjusted is first subjected to wavelet transformation, and the transformed coefficients are quantized. The quantized coefficients are arranged in a two-dimensional image according to a specific scanning order, and the two-dimensional image is encoded using a video encoder. The reconstructed displacement information is applied to the subdivided base mesh to obtain a reconstructed subdivided and deformed mesh, and the mesh, the original input mesh and its corresponding texture map are input into the corresponding texture map conversion module to obtain the texture map corresponding to the reconstructed mesh, and the texture map is also encoded using a video encoder. The parameters used in the encoding process, such as the type of video encoder used, the type of grid encoder, transform parameters, quantization parameters, etc., are transmitted to the decoding end through auxiliary information.

[0047] The overall framework of the decoding end is shown in Figure 2(b). For the received bitstream, the decoding end demultiplexes each part of the bitstream to obtain the basic grid bitstream, displacement video bitstream, texture map video bitstream and auxiliary information bitstream respectively; for the basic grid bitstream, the grid decoder indicated by the auxiliary information is used to decode the basic grid; the displacement video bitstream and the texture map video bitstream are decoded by the video decoder; for the displacement part, after the video is decoded, the displacement needs to be taken out from the image through the displacement decoding module, and inverse quantization, inverse transformation and other steps are performed, and then it is applied to the subdivided basic grid to obtain the deformed grid reconstructed by the decoding end; the texture map after decoding is the texture map corresponding to the reconstructed deformed grid, and the subsequent application or rendering module uses the reconstructed deformed grid and the decoded texture map as input for processing.

[0048] In view of this, considering that making the compression method of the three-dimensional mesh model compatible with the V3C standard is conducive to the promotion and applicability of the method. The present invention provides a three-dimensional mesh encoding and decoding method, which optimizes the three-dimensional mesh encoding and decoding method in VDMC and combines the optimization method with the V3C standard; that is, when encoding the basic mesh, it is divided into sub-meshes of different types, and different encoding methods are used to encode the sub-meshes of different types, which can improve the flexibility of encoding and decoding.

[0049] See also Figure 3 As shown, Figure 3is a flow chart of a three-dimensional mesh coding method provided by an embodiment of the present invention. The three-dimensional mesh coding method provided by the present invention includes:

[0050] S101, obtaining a reference grid and a reference grid division, and dividing the reference grid into at least one sub-reference grid according to the reference grid division;

[0051] S102, obtaining a grid to be encoded and a grid division to be encoded, and dividing the grid to be encoded into at least one sub-grid to be encoded according to the grid division to be encoded;

[0052] S103: Determine whether the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding.

[0053] For more details, please see Figure 3 As shown, the present embodiment provides a three-dimensional grid encoding method, which improves the encoding process of the basic grid in the VDMC encoding process in the prior art; that is, according to the division of the grid to be encoded, the grid to be encoded is divided into at least one sub-grid to be encoded; according to the division of the reference grid, the reference grid is divided into at least one sub-reference grid; wherein, for each sub-grid to be encoded, an intra-frame encoding mode or an inter-frame encoding mode will be adopted. For the sub-grid to be encoded using the intra-frame encoding mode, the information of the sub-reference grid is not used for encoding. For the sub-grid to be encoded using the inter-frame encoding mode, the information of the sub-reference grid is used for encoding. For each sub-grid to be encoded using the inter-frame encoding mode, a sub-reference grid uniquely corresponding to it will be determined in the reference frame, and the sub-grid to be encoded will be determined to be encoded using the information of the sub-reference grid. Furthermore, it is possible to further determine whether the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding; it can be understood that if the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding, the sub-grid to be encoded is divided into one type of sub-grid; if the sub-grid to be encoded does not use all or part of the information of the sub-reference grid for encoding, the sub-grid to be encoded is divided into another type of sub-grid; in this way, when encoding the basic grid, the basic grid is divided into different types of sub-grids, and different encoding methods are used to encode different types of sub-grids. This differentiated encoding method can improve the flexibility of encoding, refine the encoding, and improve the accuracy of encoding.

[0054] It should be noted that the scheme is for basic grid description, which is applicable to grid coding of non-basic grids and non-triangular grids, and the geometric information coding is also applicable to point cloud coding.

[0055] In an optional embodiment of the present invention, please continue to refer to Figure 4 As shown, Figure 4It is a schematic diagram of basic grid division provided by an embodiment of the present invention, and determining whether the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding includes:

[0056] Obtaining first index information, where the first index information is used to guide the encoding type;

[0057] If the first index information is an illegal value, it is determined that the sub-grid to be encoded does not use all or part of the information of the sub-reference grid for encoding; or,

[0058] If the first index information is a legal value, it is determined that the sub-grid to be encoded is encoded using all or part of the information of the sub-reference grid whose index is the first index information.

[0059] Another possibility is: when the first index information is a first value, it is determined that the sub-grid to be encoded does not use all or part of the information of the sub-reference grid for encoding; when the first index information is a second value, it is determined that the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding; when the first index information is a second value, a third value is further obtained as the index information of the sub-reference grid.

[0060] For more details, please see Figure 4 As shown, in this embodiment, the encoding end determines whether to use the sub-reference grid and which sub-reference grid information to encode according to the rate-distortion cost; further, the encoding end obtains the first index information, and the first index information is used to guide the encoding type; by judging whether the first index information is an illegal value or a legal value, it is judged whether to use the sub-reference grid information for encoding, and the first index information is an illegal value, such as -1, that is, the basic grid is divided into intra-frame sub-grids, and the information encoding of all or part of the sub-reference grids is not used, and the sub-grid to be encoded is encoded using the intra-frame coding mode. For example, the static grid already available in VDMC can be used. The encoder encodes the sub-grid to be encoded in intra-frame mode; the first index information is a legal value, such as a non-negative integer, that is, the basic grid is divided into inter-frame sub-grids, and the information of the sub-reference grid indexed by all or part of the first index information is encoded, and the sub-grid to be encoded is encoded using the inter-frame coding mode. For example, the reference information of the sub-grid to be encoded and the motion vector information of the sub-reference grid are generally encoded; in this way, the basic grid is divided into intra-frame sub-grids and inter-frame sub-grids, and they are encoded respectively using different encoding methods. This differentiated processing method can obtain the encoded basic grid code stream information more accurately.

[0061] In an optional embodiment of the present invention, if it is determined that the sub-grid to be encoded uses all or part of the information of the sub-reference grid indexed as the first index information for encoding, first identification information is obtained, and based on the first identification information, it is determined to use all or part of the sub-reference grid as reference information for encoding; wherein the first identification information is used to guide the encoding content range.

[0062] Specifically, in this embodiment, on the basis of determining that the sub-grid to be encoded uses all or part of the information encoding of the sub-reference grid indexed as the first index information, first identification information is obtained, and the first identification information is used to guide the encoding content range, that is, the encoding reference range identifier, indicating that the current sub-grid to be encoded uses the entire area of ​​the sub-reference grid or a partial area of ​​the sub-reference grid; in this way, the sub-grid to be encoded uses all or part of the sub-reference grid information encoding, and this differentiated processing method can more finely obtain the encoded basic grid code stream information.

[0063] In an optional embodiment of the present invention, determining, according to the first identification information, to use all or part of the sub-reference grid as reference information for encoding includes:

[0064] If the first identification information is the first type of information, determining to use part of the sub-reference grid as reference information for encoding; or,

[0065] If the first identification information is the second type of information, it is determined to use the entire sub-reference grid as reference information for encoding.

[0066] Specifically, in this embodiment, on the basis of determining that the sub-grid to be encoded uses all or part of the information encoding of the sub-reference grid indexed by the first index information, the first identification information is the first type of information, that is, the first identification information indicates that the reference is a partial area of ​​the sub-reference grid, and the first identification information is the second type of information, that is, the first identification information indicates that the reference is the entire area of ​​the sub-reference grid; in this way, the partial area or the entire area of ​​the sub-reference grid is finely distinguished during the encoding process, so that the encoded basic grid code stream information can be obtained more finely.

[0067] In an optional embodiment of the present invention, determining to use a portion of the sub-reference grid as reference information for encoding includes:

[0068] The second index information is obtained, and based on the second index information, which parts of the sub-reference grid are used as references is determined. The information identifying which parts of the sub-reference grid are used as references includes each index value, and / or a reference index type, and / or the number of indexes corresponding to the index type.

[0069] Specifically, in this embodiment, on the basis of determining to use part of the sub-reference grid as the reference information encoding, it is necessary to further determine which part of the area of ​​the sub-reference grid is to be used; further, obtain second index information, the second index information is used to indicate the content of the encoded sub-reference grid, that is, determine the index value of the part of the sub-reference grid to be used, and may also include an index type and the number of indexes corresponding to the index type; it can also be understood that the second index information is used to indicate which index information of the partial area of ​​the sub-reference grid is encoded, and possible index types include a patch index type or a vertex index type, and the corresponding type index of the partial area of ​​the sub-reference grid is encoded, that is, the patch index or the vertex index is encoded, and according to the category identifier of the second index information, the number of indexes corresponding to the corresponding index type in the partial area of ​​the sub-reference grid is calculated, and the number of indexes is encoded; in this way, the encoded content is accurately distinguished, and the encoded basic grid code stream information can be obtained more precisely.

[0070] In an optional embodiment of the present invention, please continue to refer to Figure 5 and Figure 6 As shown, Figure 5 is a schematic diagram of basic grid division provided by an embodiment of the present invention, Figure 6 It is a schematic diagram of basic grid division provided by an embodiment of the present invention, and determining that a sub-grid to be encoded uses information of a sub-reference grid whose index is all or part of the first index information for encoding, including:

[0071] Obtain second identification information, and determine whether the sub-grid to be encoded uses all or part of the motion vector of the sub-reference grid for encoding based on the second identification information; wherein the second identification information is used to guide the encoding content.

[0072] For more details, please see Figure 5 and Figure 6 As shown, in this embodiment, on the basis of determining that the sub-grid to be encoded uses all or part of the information encoding of the sub-reference grid indexed as the first index information, that is, determining to divide the basic grid into inter-frame sub-grids, the type of the sub-grid to be encoded is further confirmed; it can be understood that the second identification information is obtained, and the second identification information is used to guide the encoding content, and according to the second identification information, it is determined whether the sub-grid to be encoded uses all or part of the motion vector of the sub-reference grid for encoding; it can also be understood that, further, the sub-grid to be encoded is divided into two categories, P sub-grids or Skip sub-grids; or, the sub-grid to be encoded is divided into P blocks or Skip blocks; in this way, the type of the sub-grid to be encoded is further confirmed, and the encoded basic grid code stream information can be obtained more finely.

[0073] Specifically, if the sub-grid to be encoded is a P sub-grid or a P block, in the encoding process, all or part of the motion vectors of the sub-reference grid need to be encoded, and the encoding process includes:

[0074] Divide the vertices into multiple groups of 16 vertices according to the vertex index order of the sub-reference mesh;

[0075] Setting a type identifier for the motion vector and motion vector prediction residual of each group of vertices, and encoding the type identifier of the motion vector and motion vector prediction residual of each group of vertices;

[0076] According to the motion vector and motion vector prediction residual type identifier of each group of vertices, the motion vector or motion vector prediction residual of each group of vertices is encoded in turn; it should be noted that the bit overhead of encoding the motion vector or encoding the motion vector residual is to select a coding method with low bit overhead.

[0077] Please refer to Figure 5 As shown, if the sub-grid to be encoded is an inter-frame sub-grid, the inter-frame sub-grid needs to be divided into a P sub-grid or a Skip sub-grid; when the sub-grid to be encoded is a P sub-grid, all or part of the motion vector information of its sub-reference grid needs to be encoded, and when the sub-grid to be encoded is a Skip sub-grid, the motion vector information of its sub-reference grid is not encoded.

[0078] Please refer to Figure 6 As shown, if the sub-grid to be encoded is an inter-frame sub-grid, it is necessary to divide the inter-frame sub-grid into several blocks, and perform inter-frame mode encoding with the block as the basic unit; further, first encode the number of blocks divided by the current inter-frame sub-grid, and then perform inter-frame mode encoding on a block-by-block basis, and the content of block-by-block encoding includes the reference information of the block to be encoded and all or part of the motion vector information of the sub-reference grid; according to whether the motion vector information of the sub-reference grid is encoded, the inter-frame block can be divided into two categories: P block or Skip block. When the block to be encoded is a P block, it is necessary to encode all or part of the motion vector information of its sub-reference grid; when the block to be encoded is a Skip block, the motion vector information of its sub-reference grid is not encoded.

[0079] In an optional embodiment of the present invention, please continue to refer to Figure 5 and Figure 6 As shown, according to the second identification information, determining whether the sub-grid to be encoded uses all or part of the motion vectors of the sub-reference grid for encoding includes:

[0080] If the second identification information is of the first type, determining that the sub-grid to be encoded uses all or part of the motion vectors of the sub-reference grid for encoding; or,

[0081] If the second identification information is of the second type, it is determined that the sub-grid to be encoded does not use all or part of the motion vectors of the sub-reference grid for encoding.

[0082] For more details, please see Figure 5 and Figure 6 As shown, in this embodiment, the type of the second identification information is first determined, that is, the type of the sub-grid to be encoded is determined, and then different encoding methods are used to encode the sub-grid to be encoded; if the second identification information of the sub-grid to be encoded to be encoded is of the first type, the sub-grid to be encoded is determined to be a P sub-grid, and the reference information of the sub-grid to be encoded and the motion vector information of the sub-reference grid need to be encoded; if the second identification information of the sub-grid to be encoded to be encoded is of the second type, the sub-grid to be encoded is determined to be a Skip sub-grid, and only the reference information of the sub-grid to be encoded needs to be encoded; or, if the second identification information of the sub-grid to be encoded to be encoded is of the first type, the sub-grid to be encoded is determined to be a P block, and the reference information of the sub-grid to be encoded and the motion vector information of the sub-reference grid need to be encoded; if the second identification information of the sub-grid to be encoded to be encoded is of the second type, the sub-grid to be encoded is determined to be a Skip block, and only the reference information of the sub-grid to be encoded needs to be encoded; in this way, the type of the sub-grid to be encoded is further confirmed, and the encoded basic grid code stream information can be obtained more precisely.

[0083] Based on the same invention concept, please continue to refer to Figure 7 As shown, Figure 7 is a flow chart of a three-dimensional mesh decoding method provided by an embodiment of the present invention. The present invention also provides a three-dimensional mesh decoding method, corresponding to a three-dimensional mesh encoding method, the decoding method comprising:

[0084] S201, obtaining a reference grid and a reference grid division, and dividing the reference grid into at least one sub-reference grid according to the reference grid division;

[0085] S202, obtaining a to-be-decoded grid and a to-be-decoded grid division, and dividing the to-be-decoded grid into at least one sub-to-be-decoded grid according to the to-be-decoded grid division;

[0086] S203: Determine whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding.

[0087] For more details, please see Figure 7As shown, the present embodiment provides a decoding method for a three-dimensional grid, which decodes the code stream information of the basic grid obtained in the encoding process of the above embodiment, and then reconstructs the basic grid; corresponding to the encoding process, the grid to be decoded is divided into at least one sub-grid to be decoded according to the division of the grid to be decoded; the reference grid is divided into at least one sub-reference grid according to the division of the reference grid; wherein, for each grid to be decoded, an intra-frame decoding mode or an inter-frame decoding mode will be adopted. The sub-grid to be decoded in the intra-frame decoding mode does not use the information of the sub-reference grid for decoding; the sub-grid to be decoded in the inter-frame decoding mode uses the information of the sub-reference grid for decoding. For each sub-grid to be decoded in the inter-frame decoding mode, there will be a sub-reference grid that uniquely corresponds to it, and it is determined that the sub-grid to be decoded uses the information of the sub-reference grid. Furthermore, it is possible to further determine whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding; it can be understood that, in the decoding process, the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding, then according to a type of sub-grid corresponding to the sub-grid to be decoded, it is decoded using a corresponding decoding method; if the sub-grid to be decoded does not use all or part of the information of the sub-reference grid for decoding, then according to another type of sub-grid corresponding to the sub-grid to be decoded, it is decoded using a corresponding decoding method; in this way, according to the division of the sub-grids to be encoded in the encoding process, the corresponding decoding method is used to decode the sub-grids to be decoded in the decoding process, which can improve the flexibility of decoding, achieve refined decoding, and improve the accuracy of information transmission.

[0088] It should be noted that the scheme is described for the basic grid code stream, which is applicable to non-basic grid code stream decoding and non-triangular grid. The geometric information code stream decoding is also applicable to point cloud code stream decoding.

[0089] In an optional embodiment of the present invention, please continue to refer to Figure 8 As shown, Figure 8 This is a schematic diagram of basic grid code stream decoding provided by an embodiment of the present invention, and determining whether a sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding, including:

[0090] Obtaining first index information, where the first index information is used to guide the decoding type;

[0091] If the first index information is an illegal value, it is determined that the sub-grid to be decoded does not use all or part of the information of the sub-reference grid for decoding; or,

[0092] If the first index information is a legal value, it is determined that the sub-grid to be decoded uses all or part of the information of the sub-reference grid whose index is the first index for decoding.

[0093] Another possibility is that when the first index information is a first value, it is determined that the sub-grid to be decoded does not use all or part of the information of the sub-reference grid for decoding; when the first index information is a second value, it is determined that the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding; when the first index information is a second value, a third value is further obtained as the index information of the sub-reference grid.

[0094] For more details, please see Figure 8 As shown, in this embodiment, the decoding end will obtain the first index information, and the first index information is used to guide the decoding type, that is, the decoding end first decodes the index of the sub-reference grid of the sub-grid to be decoded, and determines the type of the sub-grid to be decoded according to whether the index of the sub-reference grid is legal or not, and then decodes the sub-grid to be decoded using different decoders according to the type of the first index information; the first index information is an illegal value, such as -1, that is, the sub-grid code stream to be decoded is an intra-frame sub-grid code stream, and the intra-frame mode is used for decoding. Optionally, the sub-grid code stream to be decoded is decoded in intra-frame mode using the existing static grid decoder of VDMC. After decoding The intra-frame sub-grid is obtained; the first index information is a legal value, such as a non-negative integer, that is, the sub-grid code stream to be decoded is an inter-frame sub-grid code stream, and the inter-frame mode is used for decoding to obtain the inter-frame sub-grid after decoding; finally, the obtained sub-grids are merged and spliced ​​to obtain the decoded basic grid; in this process, it is also necessary to determine whether to use all or part of the information of the sub-reference grid indexed by the first index information for decoding; in this way, first determine whether the basic grid code stream corresponds to the intra-frame sub-grid code stream or the inter-frame sub-grid code stream, and then use different decoding methods to decode them respectively. This differentiated processing method can obtain the decoded basic grid information more accurately.

[0095] In an optional embodiment of the present invention, if it is determined that a sub-grid to be decoded uses all or part of the information of a sub-reference grid indexed by the first index information for decoding, first identification information is obtained, and based on the first identification information, it is determined to use all or part of the sub-reference grid as reference information for decoding; wherein the first identification information is used to guide the decoding content range.

[0096] Specifically, in this embodiment, on the basis of determining that the sub-grid to be decoded uses all or part of the information decoding of the sub-reference grid indexed as the first index information, first identification information is obtained, and the first identification information is used to guide the decoding content range, that is, the decoding reference range identifier, indicating that the current sub-grid to be decoded uses the entire area of ​​the sub-reference grid or a part of the sub-reference grid for decoding; it can be understood that according to the first index information of the decoded sub-grid to be decoded, the sub-reference grid of the sub-grid to be decoded in the reference grid is determined, and according to the first identification information, it is further judged in the decoding process whether it is all of the sub-reference grid or part of the sub-reference grid that is referenced; in this way, using a differentiated processing method, the decoded basic grid information can be obtained more finely.

[0097] In an optional embodiment of the present invention, determining, according to the first identification information, to use all or part of the sub-reference grid as reference information for decoding includes:

[0098] If the first identification information is the first type of information, determining to use part of the sub-reference grid as reference information for decoding; or,

[0099] If the first identification information is the second type of information, it is determined to use the entire sub-reference grid as reference information for decoding.

[0100] Specifically, in this embodiment, on the basis of determining that the sub-grid to be decoded uses all or part of the information decoding of the sub-reference grid indexed by the first index information, when the first identification information is the first type of information, that is, the first identification information indicates that the decoding is for a partial area of ​​the sub-reference grid, it is necessary to further decode the reference sub-grid index information, and obtain the vertex positions and connection relationships of the corresponding reference partial area in the sub-reference grid according to the index information; when the first identification information is the second type of information, that is, the first identification information indicates that the decoding is for the entire area of ​​the sub-reference grid, it is necessary to further decode the reference sub-grid index information, and obtain all vertex positions and connection relationships in the sub-reference grid according to the index information; in this way, the partial area or the entire area of ​​the sub-reference grid is finely distinguished during the decoding process, so that the decoded basic grid information can be obtained more accurately.

[0101] In an optional embodiment of the present invention, determining to use a portion of the sub-reference grid as reference information for decoding includes:

[0102] Obtain second index information, and determine which parts of the sub-reference grid to use as references based on the second index information. First, decode the reference index type of the sub-reference grid and the number of indexes corresponding to the index type, and then decode the index value corresponding to the reference index type.

[0103] Specifically, in this embodiment, on the basis of determining to use part of the sub-reference grid as the reference information for decoding, it is necessary to further determine which part of the sub-reference grid is to be decoded; further, obtain second index information, the second index information is used to indicate the content of the decoded sub-reference grid, decode the second index information of the sub-grid to be decoded, and obtain which index of the sub-reference grid partial area is encoded, and possible index types include patch index type or vertex index type; first, decode the number of indexes of the corresponding index type, and then decode the corresponding type index of the sub-reference grid partial area according to the index category identifier; search for the position and connection relationship of the corresponding vertex in the specified sub-reference grid according to the reference sub-grid index type and the reference sub-grid index; in this way, corresponding decoding is performed according to the encoded content, so that the basic grid information can be obtained more accurately.

[0104] In an optional embodiment of the present invention, please continue to refer to Figure 8 As shown, determining that the sub-grid to be decoded does not use all or part of the information of the sub-reference grid for decoding includes:

[0105] The sub-grid to be decoded is decoded using the first decoding mode.

[0106] For more details, please see Figure 8 As shown, in this embodiment, for the case where the sub-grid to be decoded does not use all or part of the information of the sub-reference grid for decoding, that is, the intra-frame sub-grid code stream is obtained, and the sub-grid to be decoded is decoded using the first decoding mode, that is, the intra-frame mode is used for decoding, and optionally, the sub-grid code stream to be decoded using the existing static grid decoder of VDMC is decoded in the intra-frame mode to obtain the intra-frame sub-grid after decoding.

[0107] In an optional embodiment of the present invention, see Fig. 9 and Fig.10 As shown, Fig. 9 is a schematic diagram of basic grid code stream decoding provided by an embodiment of the present invention, Fig.10 It is a schematic diagram of basic grid code stream decoding provided by an embodiment of the present invention, and determining that a sub-grid to be decoded uses information of a sub-reference grid whose index is all or part of the first index information for decoding, including:

[0108] Obtain second identification information, and determine whether the sub-grid to be decoded uses all or part of the motion vectors of the sub-reference grid for decoding based on the second identification information; wherein the second identification information is used to guide the decoding content.

[0109] For more details, please see Fig. 9 and Fig.10As shown, in this embodiment, on the basis of determining that the sub-grid to be decoded uses all or part of the information decoding of the sub-reference grid indexed as the first index information, it is determined that the inter-frame sub-grid code stream is decoded; the decoding end first decodes the reference information of the sub-grid to be decoded, and then decides whether to continue decoding all or part of the motion vector of the sub-reference grid based on the decoded reference information; in this way, corresponding decoding is performed according to the encoded content, so that the basic grid information can be obtained more accurately.

[0110] In an optional embodiment of the present invention, please continue to refer to Fig. 9 and Fig.10 As shown, according to the second identification information, determining whether the sub-grid to be decoded uses all or part of the motion vectors of the sub-reference grid for decoding includes:

[0111] If the second identification information is of the first type, determining that the sub-grid to be decoded uses all or part of the motion vectors of the sub-reference grid for decoding; or,

[0112] If the second identification information is of the second type, it is determined that the sub-grid to be decoded does not use all or part of the motion vectors of the sub-reference grid for decoding.

[0113] Specifically, in this embodiment, the second identification information is of the first type, and the decoded reference information indicates that the encoding end has encoded all or part of the motion vectors of the sub-reference grid, then it is necessary to continue decoding all or part of the motion vectors of the sub-reference grid, and then obtain the decoded P sub-grid; the second identification information is of the second type, and the decoded reference information indicates that the encoding end has not encoded all or part of the motion vectors of the sub-reference grid, then all or part of the sub-reference grid obtained according to the reference information is the decoded Skip sub-grid, and after the basic grid code stream is decoded, the sub-grids are merged and spliced ​​to generate a decoded and reconstructed basic grid.

[0114] In an optional embodiment of the present invention, determining that a sub-grid to be decoded uses all or part of the motion vectors of a sub-reference grid for decoding includes:

[0115] Decoding the sub-grid to be decoded using the second decoding mode, including decoding the sub-grid to be decoded using all or part of the motion vectors of the sub-reference grid;

[0116] Decoding the sub-grid to be decoded using all or part of the motion vector of the sub-reference grid includes:

[0117] Decoding the type identification of the motion vector and the motion vector prediction residual of each group of vertices to obtain the type identification information of the motion vector and the motion vector prediction residual of each group of vertices;

[0118] According to the type identification information of the motion vectors and motion vector prediction residuals of each group of vertices, the motion vectors or motion vector prediction residuals of each group of vertices are decoded in turn.

[0119] Specifically, in this embodiment, on the basis of determining that the sub-grid to be decoded uses all or part of the motion vector decoding of the sub-reference grid, that is, determining that the sub-grid to be decoded code stream is a P sub-grid code stream, the sub-grid to be decoded is decoded using the second decoding mode; first, the motion vector encoding method of a group of vertices of the sub-reference grid is decoded. If the encoding method is encoding motion vectors, the decoded motion vector is the motion vector of each vertex. If the decoding method is encoding motion vector residuals, the decoding end needs to perform motion vector prediction consistent with the encoding end to obtain a motion vector prediction value, and then add the decoded motion vector residual to the motion vector prediction value to obtain the motion vector of each vertex.

[0120] In an optional embodiment of the present invention, determining that the sub-grid to be decoded does not use all or part of the motion vectors of the sub-reference grid for decoding includes:

[0121] The sub-grid to be decoded is decoded using the third decoding mode.

[0122] Specifically, in this embodiment, based on determining that the sub-grid to be decoded does not use all or part of the motion vector decoding of the sub-reference grid, that is, determining that the sub-grid to be decoded code stream is a Skip sub-grid code stream, the sub-grid to be decoded is decoded using the third decoding mode, and all or part of the sub-reference grid is obtained according to the reference information, that is, the Skip sub-grid is decoded.

[0123] It should be noted that one of the overall ideas of this embodiment is that the decoding end first decodes the sub-reference grid index, determines the type of the corresponding sub-grid to be decoded according to the legitimacy of the decoded sub-reference grid index, and decodes its code stream using the corresponding mode according to the type of the sub-grid to be decoded; wherein, the code stream corresponding to the intra-frame sub-grid may be sent to the intra-frame mode decoder for decoding, and the code stream corresponding to the inter-frame sub-grid may be sent to the inter-frame mode decoder for decoding. The inter-frame mode may first decode the reference information of the sub-grid to be decoded, and then decide whether to continue to decode all or part of the motion vectors of the sub-reference grid according to the decoded reference information; if the decoded reference information indicates that the encoding end encodes all or part of the motion vectors of the sub-reference grid, it is necessary to continue to decode all or part of the motion vectors of the sub-reference grid, and then obtain the decoded P sub-grid; if the decoded reference information indicates that the encoding end does not encode all or part of the motion vectors of the sub-reference grid, then all or part of the sub-reference grid obtained according to the reference information is the decoded Skip sub-grid; after the basic grid code stream is decoded, each sub-grid is merged and spliced ​​to generate a basic grid for decoding and reconstruction.

[0124] Another overall idea of ​​the present embodiment is that the decoding end first decodes the index of the sub-reference grid of the sub-grid to be decoded, determines the type of the sub-grid to be decoded according to the index, and sends the code stream of the intra-frame sub-grid type to the intra-frame mode decoder for decoding; for the code stream of the inter-frame sub-grid type, it is sent to the inter-frame mode decoder for decoding. The inter-frame decoding mode will first decode the number of blocks in the inter-frame sub-grid, and then decode it block by block. When the inter-frame decoding mode decodes a block, it will first decode the reference information of the block to be decoded, and then decide whether to continue decoding all or part of the motion vectors of the sub-reference grid based on the decoded reference information; if the decoded reference information indicates that the encoder has encoded all or part of the motion vectors of the sub-reference grid, it is necessary to continue decoding all or part of the motion vectors of the sub-reference grid, and the decoded P block can be obtained after decoding; if the decoded reference information indicates that the encoder has not encoded all or part of the motion vectors of the sub-reference grid, then all or part of the sub-reference grid obtained according to the reference information is the decoded Skip sub-grid; after the inter-frame sub-grid code stream is decoded, the blocks are merged and spliced ​​to generate a decoded and reconstructed inter-frame sub-grid; after the basic grid code stream is decoded, the sub-grids are merged and spliced ​​to obtain a decoded and reconstructed basic grid.

[0125] In an optional embodiment of the present invention, the sub-grid-based basic grid coding and decoding syntax structure includes:

[0126] When the decoder decodes the current frame base grid, if it decodes the inter-frame sub-grid, it needs to obtain the position and connectivity relationship of each vertex in the sub-reference grid in the reference frame. Therefore, the relevant information of the sub-reference grid needs to be specified in the syntax structure to clarify the reference area. The syntax structure provided in this embodiment is designed based on the VDMC syntax structure, and the reference information should be placed in the header information of the current sub-grid.

[0127] When the decoding end can obtain the sub-grid division information of the reference frame, a reference sub-grid index syntax needs to be set in the sub-grid header information to indicate which sub-grid in the reference frame the current sub-grid refers to. The syntax structure is shown in Table 1.

[0128] Table 1 Syntax structure

[0129]

[0130]

[0131] Among them, smh_ref_ubmesh_id represents the index of the sub-reference grid that identifies the current sub-grid to be encoded. When the value is -1, it means that the sub-grid to be encoded is an intra-frame sub-grid; when the value is a non-negative integer, it means that the sub-grid to be encoded is an inter-frame sub-grid, and the numerical value represents the index of its sub-reference grid.

[0132] smh_ref_submesh_overall_flag is used to identify whether the sub-grid to be coded refers to the entire sub-reference grid or a part of the sub-reference grid. A value of 0 indicates that the sub-grid to be coded refers to a part of the sub-reference grid, and a value of 1 indicates that the sub-grid to be coded refers to the entire sub-reference grid.

[0133] smh_ref_submesh_index_type indicates the type of reference index information, as shown in Table 2 below. When the value is 0, it means that the patch index of the sub-reference mesh part area is transferred. When the value is 1, it means that the vertex index of the sub-reference mesh part area is transferred.

[0134] Table 2

[0135] smh_ref_submesh_index_type Name of smh_ref_submesh_index_type 0 TRIANGLE_INDEX 1 VERTEX_INDEX

[0136] Among them, smh_ref_submesh_index_num represents the number of reference indexes of the corresponding type in the sub-reference mesh partial area.

[0137] smh_ref_mesh_triangle_index[smh_ref_submesh_id][i] indicates the index of the triangle patch that specifies the partial area within the sub-reference mesh.

[0138] smh_ref_mesh_vertex_index[smh_ref_submesh_id][v] specifies the vertex index of a portion of the sub-reference mesh.

[0139] smh_ref_submesh_code_mv indicates whether to encode the motion vectors of all or part of the vertices of the sub-reference mesh of the sub-mesh to be encoded. When the value is 0, it means that the motion vector is not encoded, and when the value is 1, it means that the motion vector is encoded.

[0140] In an optional embodiment of the present invention, the block-based basic grid coding syntax structure includes:

[0141] The block-based basic grid codec syntax structure is designed based on the existing syntax structure of VDMC. First, a syntax needs to be set in the header information of the inter-frame sub-grid to indicate how many blocks the current inter-frame sub-grid is divided into, and then the reference information content is expressed block by block. The corresponding syntax structure is shown in Table 3.

[0142] Table 3 Syntax structure

[0143]

[0144]

[0145] Among them, smh_inter_patch_num represents the number of blocks into which the sub-grid of the current frame is divided.

[0146] smh_ref_submesh_id represents the index of the sub-reference grid that identifies the current sub-grid to be encoded. When the value is -1, it means that the sub-grid to be encoded is an intra-frame sub-grid; when the value is a non-negative integer, it means that the sub-grid to be encoded is an inter-frame sub-grid, and the numerical value represents the index of its sub-reference grid.

[0147] smh_ref_submesh_overall_flag indicates whether the sub-mesh to be coded refers to the entire sub-reference mesh or a part of the sub-reference mesh. A value of 0 indicates that the sub-mesh to be coded refers to a part of the sub-reference mesh, and a value of 1 indicates that the sub-mesh to be coded refers to the entire sub-reference mesh. smh_ref_submesh_index_type: indicates the type of reference index information, as shown in Table 4. When the value is 0, it means that the face index of the sub-reference mesh is transferred, and when the value is 1, it means that the vertex index of the sub-reference mesh is transferred.

[0148] Table 4

[0149] smh_ref_submesh_index_type Name of smh_ref_submesh_index_type 0 TRIANGLE_INDEX 1 VERTEX_INDEX

[0150] Among them, smh_ref_submesh_index_num represents the number of reference indexes of the corresponding type in the sub-reference mesh partial area.

[0151] smh_ref_mesh_triangle_index[smh_ref_submesh_id][i] indicates the index of the triangle patch that specifies the partial area within the sub-reference mesh.

[0152] smh_ref_mesh_vertex_index[smh_ref_submesh_id][v] specifies the vertex index of a portion of the sub-reference mesh.

[0153] smh_ref_submesh_code_mv indicates whether to encode the motion vectors of all or part of the vertices of the sub-reference mesh of the sub-mesh to be encoded. When the value is 0, it means that the motion vector is not encoded, and when the value is 1, it means that the motion vector is encoded.

[0154] Based on the same invention concept, please participate Fig.11 As shown, Fig.111 is a schematic diagram of a three-dimensional grid encoding device provided by an embodiment of the present invention; a three-dimensional grid encoding device 100 includes:

[0155] A first acquisition unit 101 is used to acquire a reference grid and a reference grid division, and divide the reference grid into at least one sub-reference grid according to the reference grid division;

[0156] The second acquisition unit 102 is used to acquire the to-be-coded grid and the to-be-coded grid division, and divide the to-be-coded grid into at least one sub-to-be-coded grid according to the to-be-coded grid division;

[0157] The determination unit 103 is used to determine whether the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding.

[0158] For more details, please see Fig.11 As shown, in this embodiment, the three-dimensional grid encoding device includes a first acquisition unit, a second acquisition unit and a determination unit. The encoding device can be understood as a device with a three-dimensional grid encoding function, which is used to encode the three-dimensional grid, generate a code stream, and transmit the code stream to the three-dimensional grid decoding device.

[0159] Based on the same invention concept, please participate Fig.12 As shown, Fig.12 is a schematic diagram of a three-dimensional grid decoding device provided by an embodiment of the present invention. The present invention further provides a three-dimensional grid decoding device 200, comprising:

[0160] A first acquisition unit 201 is used to acquire a reference grid and a reference grid division, and divide the reference grid into at least one sub-reference grid according to the reference grid division;

[0161] The second acquisition unit 202 is used to acquire the to-be-decoded grid and the to-be-decoded grid division, and divide the to-be-decoded grid into at least one sub-to-be-decoded grid according to the to-be-decoded grid division;

[0162] The determination unit 203 is used to determine whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding.

[0163] For more details, please see Fig.12 As shown, in this embodiment, the three-dimensional mesh decoding device includes a first acquisition unit, a second acquisition unit and a determination unit. The decoding device can be understood as a device with a three-dimensional mesh decoding function, which is used to decode the three-dimensional mesh code stream to obtain a decoded three-dimensional mesh.

[0164] It should be noted that the encoding device may transmit the encoded code stream to the decoding device via a channel, and the channel may include one or more media and / or devices capable of transmitting the encoded code stream from the encoding device to the decoding device.

[0165] It is understandable that the device embodiment and the method embodiment may correspond to each other, and similar descriptions may refer to the method embodiment. To avoid repetition, they are not described here. Specifically, Fig.11 The device shown can execute the encoding method embodiment, and the aforementioned and other operations and / or functions of each module in the device are respectively for implementing the method embodiment corresponding to the encoding device, Fig.12 The device shown can execute a decoding method embodiment, and the aforementioned and other operations and / or functions of each module in the device are respectively for implementing the method embodiment corresponding to the decoding device, which will not be described in detail here for the sake of brevity.

[0166] It should be noted that the apparatus of the embodiment of the present invention is described above from the perspective of the functional module in conjunction with the accompanying drawings. It should be understood that the functional module can be implemented in hardware form, can be implemented by instructions in software form, and can also be implemented by a combination of hardware and software modules. Specifically, the steps of the method embodiment in the embodiment of the present invention can be completed by the hardware integrated logic circuit and / or software form instructions in the processor, and the steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor to execute, or a combination of hardware and software modules in the decoding processor to execute. Optionally, the software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory, and completes the steps in the above method embodiment in conjunction with its hardware.

[0167] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant is intended to cover non-exclusive inclusion, so that the article or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the article or device including the elements. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The orientation or position relationship indicated by "up", "down", "left", "right", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0168] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0169] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the scope of protection of the present invention.

Claims

1. A three-dimensional grid coding method, characterized in that: include: Acquire a reference grid and a reference grid division, and divide the reference grid into at least one sub-reference grid according to the reference grid division; Obtaining a grid to be encoded and a grid division to be encoded, and dividing the grid to be encoded into at least one sub-grid to be encoded according to the grid division to be encoded; Determine whether the sub-grid to be encoded is encoded using all or part of the information of the sub-reference grid.

2. The three-dimensional grid coding method according to claim 1, characterized in that: The determining whether the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding includes: Acquire first index information, where the first index information is used to guide the encoding type; If the first index information is an illegal value, it is determined that the sub-grid to be encoded does not use all or part of the information of the sub-reference grid for encoding; or, If the first index information is a legal value, it is determined that the sub-grid to be encoded is encoded using all or part of the information of the sub-reference grid indexed by the first index information.

3. The three-dimensional grid coding method according to claim 2, characterized in that: If it is determined that the sub-grid to be encoded uses all or part of the information of the sub-reference grid indexed by the first index information for encoding, first identification information is obtained, and based on the first identification information, it is determined to use all or part of the sub-reference grid as reference information for encoding; wherein the first identification information is used to guide the encoding content range.

4. The three-dimensional grid coding method according to claim 3, characterized in that: The step of determining, according to the first identification information, to use all or part of the sub-reference grid as reference information for encoding includes: If the first identification information is the first type of information, determining to use part of the sub-reference grid as reference information for encoding; or, If the first identification information is the second type of information, it is determined to use the entire sub-reference grid as reference information for encoding.

5. The three-dimensional grid coding method according to claim 4, characterized in that: The determining to use the portion of the sub-reference grid as reference information for encoding comprises: Obtain second index information, and determine, based on the second index information, to use a reference index type of part of the sub-reference grid, the number of indexes corresponding to the index type, and each index value for encoding.

6. The three-dimensional grid coding method according to claim 2, characterized in that: The determining that the sub-grid to be encoded uses information of the sub-reference grid whose index is all or part of the first index information for encoding includes: Obtain second identification information, and determine whether the sub-grid to be encoded uses all or part of the motion vector of the sub-reference grid for encoding based on the second identification information; wherein the second identification information is used to guide the encoding content.

7. The three-dimensional grid coding method according to claim 6, characterized in that: The determining, according to the second identification information, whether the sub-grid to be encoded uses all or part of the motion vectors of the sub-reference grid for encoding includes: If the second identification information is of the first type, determining that the sub-grid to be encoded is encoded using all or part of the motion vectors of the sub-reference grid; or, If the second identification information is of the second type, it is determined that the sub-grid to be encoded is not encoded using all or part of the motion vectors of the sub-reference grid.

8. A three-dimensional grid decoding method, characterized in that: include: Acquire a reference grid and a reference grid division, and divide the reference grid into at least one sub-reference grid according to the reference grid division; Obtaining a to-be-decoded grid and a to-be-decoded grid division, and dividing the to-be-decoded grid into at least one sub-to-be-decoded grid according to the to-be-decoded grid division; Determine whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding.

9. The three-dimensional grid decoding method according to claim 8, characterized in that: The determining whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding includes: Acquire first index information, where the first index information is used to guide a decoding type; If the first index information is an illegal value, it is determined that the sub-grid to be decoded does not use all or part of the information of the sub-reference grid for decoding; or, If the first index information is a legal value, it is determined that the sub-grid to be decoded uses all or part of the information of the sub-reference grid indexed by the first index information for decoding.

10. The three-dimensional grid decoding method according to claim 9, characterized in that: If it is determined that the sub-grid to be decoded uses all or part of the information of the sub-reference grid indexed by the first index information for decoding, first identification information is obtained, and based on the first identification information, it is determined to use all or part of the sub-reference grid as reference information for decoding; wherein the first identification information is used to guide the decoding content range.

11. The three-dimensional grid decoding method according to claim 10, characterized in that: The step of determining, according to the first identification information, to use all or part of the sub-reference grid as reference information for decoding includes: If the first identification information is the first type of information, determining to use part of the sub-reference grid as reference information for decoding; or, If the first identification information is the second type of information, it is determined to use all of the sub-reference grid as reference information for decoding.

12. The three-dimensional grid decoding method according to claim 11, characterized in that: The determining to use a portion of the sub-reference grid as reference information for decoding includes: Obtain second index information, and according to the second index information, first decode the reference index type of the sub-reference grid and the number of indexes corresponding to the index type, and then decode the index value corresponding to the reference index type.

13. The three-dimensional grid decoding method according to claim 9, characterized in that: The determining that the sub-grid to be decoded does not use all or part of the information of the sub-reference grid for decoding includes: The sub-grid to be decoded is decoded using a first decoding mode.

14. The three-dimensional grid decoding method according to claim 9, characterized in that: The determining that the sub-grid to be decoded uses information of the sub-reference grid whose index is all or part of the first index information for decoding includes: Obtain second identification information, and determine whether the sub-grid to be decoded uses all or part of the motion vector of the sub-reference grid for decoding based on the second identification information; wherein the second identification information is used to guide the decoding content.

15. The three-dimensional grid decoding method according to claim 14, characterized in that: The determining, according to the second identification information, whether the sub-grid to be decoded uses all or part of the motion vectors of the sub-reference grid for decoding includes: If the second identification information is of the first type, determining that the sub-grid to be decoded uses all or part of the motion vectors of the sub-reference grid for decoding; or, If the second identification information is of the second type, it is determined that the sub-grid to be decoded does not use all or part of the motion vectors of the sub-reference grid for decoding.

16. The three-dimensional grid decoding method according to claim 15, characterized in that: The determining that the sub-grid to be decoded uses all or part of the motion vectors of the sub-reference grid for decoding includes: Decoding the sub-grid to be decoded using a second decoding mode, including decoding the sub-grid to be decoded using all or part of the motion vectors of the sub-reference grid; The decoding of the sub-grid to be decoded using all or part of the motion vectors of the sub-reference grid comprises: Decoding the type identification of the motion vector and the motion vector prediction residual of each group of vertices to obtain type identification information of the motion vector and the motion vector prediction residual of each group of vertices; According to the type identification information of the motion vectors and motion vector prediction residuals of each group of vertices, the motion vectors or motion vector prediction residuals of each group of vertices are decoded in turn.

17. The three-dimensional grid decoding method according to claim 15, characterized in that: The determining that the sub-grid to be decoded does not use all or part of the motion vectors of the sub-reference grid for decoding includes: The sub-grid to be decoded is decoded using a third decoding mode.

18. A three-dimensional grid encoding device, characterized in that: include: A first acquisition unit, configured to acquire a reference grid and a reference grid division, and divide the reference grid into at least one sub-reference grid according to the reference grid division; A second acquisition unit is used to acquire a grid to be encoded and a grid division to be encoded, and divide the grid to be encoded into at least one sub-grid to be encoded according to the grid division to be encoded; A determination unit is used to determine whether the sub-grid to be encoded uses all or part of the information of the sub-reference grid for encoding.

19. A three-dimensional grid decoding device, characterized in that: include: A first acquisition unit, configured to acquire a reference grid and a reference grid division, and divide the reference grid into at least one sub-reference grid according to the reference grid division; A second acquisition unit is used to acquire a to-be-decoded grid and a to-be-decoded grid division, and divide the to-be-decoded grid into at least one sub-to-be-decoded grid according to the to-be-decoded grid division; A determination unit is used to determine whether the sub-grid to be decoded uses all or part of the information of the sub-reference grid for decoding.

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