WO2025039125A1 - Encoding method, decoding method, encoder, decoder, and storage medium - Google Patents

Abstract

Embodiments of the present application provide an encoding method, a decoding method, an encoder, a decoder, and a storage medium. The encoding method comprises: determining a repetition point set of a point cloud to be encoded, wherein repetition points in the repetition point set comprise a plurality types of attribute information; and on the basis of the plurality types of attribute information, sorting the repetition points in the repetition point set.

Description

Coding and decoding method, codec and storage medium Technical Field

The present application relates to the technical field of point cloud encoding and decoding, and in particular to an encoding and decoding method, a codec and a storage medium.

Background Art

In the related point cloud coding technology, after completing the geometric coding, the encoding end will sort the attribute information of the duplicate points (in ascending order). If the duplicate points have multiple attribute information, the related technology will sort the multiple attribute information of the duplicate points separately, which may cause the attribute coding to be lossy.

Summary of the invention

The embodiments of the present application provide a coding method, a codec and a storage medium, which are helpful to reduce the loss of attribute coding and improve coding performance.

In a first aspect, a coding method is provided, which is applied to an encoder, and the method comprises: determining a set of repeated points of a point cloud to be encoded; wherein the repeated points in the set of repeated points include multiple attribute information; and sorting the repeated points in the set of repeated points according to the multiple attribute information.

In a second aspect, a decoding method is provided, which is applied to a decoder, and the method includes: parsing a bit stream to determine a value of a first parameter; if the value of the first parameter is a first value, performing a repeated point decoding operation; wherein the value of the first parameter includes a first value and a second value, the first value is used to indicate that the repeated point decoding operation is performed, and the second value is used to indicate that the repeated point decoding operation is not performed.

According to a third aspect, a coding method is provided, which is applied to an encoder, and the method includes: determining whether to perform a repeated point coding operation; determining a value of a first parameter according to a determination result; encoding the value of the first parameter, and writing the obtained coded bits into a bit stream; wherein the value of the first parameter includes a first value and a second value, the first value is used to indicate that the repeated point coding operation is performed, and the second value is used to indicate that the repeated point coding operation is not performed.

In a fourth aspect, an encoder is provided, comprising: a determination unit configured to determine a set of repeated points in a point cloud to be encoded; wherein the repeated points in the set of repeated points include multiple attribute information; and a sorting unit configured to sort the repeated points in the set of repeated points according to the multiple attribute information.

According to a fifth aspect, an encoder is provided, comprising: a memory for storing a computer program; and a processor for executing the method described in the first aspect when running the computer program.

In a sixth aspect, a decoder is provided, comprising: a first decoding unit, configured to parse a bitstream and determine a value of a first parameter; a second decoding unit, configured to perform a repeated point decoding operation if the value of the first parameter is a first value; wherein the value of the first parameter comprises a first value and a second value, the first value being used to indicate that the repeated point decoding operation is to be performed, and the second value being used to indicate that the repeated point decoding operation is not to be performed.

According to a seventh aspect, a decoder is provided, comprising: a memory for storing a computer program; and a processor for executing the method described in the second aspect when running the computer program.

In an eighth aspect, an encoder is provided, comprising: a determination unit, configured to determine whether to perform a repeated point coding operation, and determine a value of a first parameter based on a determination result; an encoding unit, configured to encode the value of the first parameter, and write the obtained coded bits into a bit stream; wherein the value of the first parameter comprises a first value and a second value, the first value is used to indicate that the repeated point coding operation is performed, and the second value is used to indicate that the repeated point coding operation is not performed.

In a ninth aspect, an encoder is provided, comprising: a memory for storing a computer program; and a processor for executing the method described in the third aspect when running the computer program.

In a tenth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed, the method as described in any one of the first to third aspects is implemented.

When a repeated point contains multiple attribute information, the related art sorts the multiple attribute information separately, which may destroy the correlation between the multiple attribute information, thereby causing attribute coding loss. Different from the related art, the embodiment of the present application uniformly sorts the multiple attribute information of the repeated point based on the first attribute information, thereby avoiding destroying the correlation between the multiple attribute information, reducing the coding loss of the attribute coding, and improving the coding performance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic diagram of a three-dimensional point cloud image.

FIG. 1B is a partially enlarged view of a three-dimensional point cloud image.

FIG. 2A is a schematic diagram of six viewing angles of a point cloud image.

FIG. 2B is a schematic diagram of a data storage format corresponding to a point cloud image.

FIG3 is a schematic diagram of a network architecture for point cloud encoding and decoding.

FIG. 4 is a schematic diagram of a reference node of a child node.

FIG. 5 is a schematic diagram showing the occupancy of neighbor nodes of the current node layer.

FIG. 6 is a schematic diagram showing the positional relationship between a child block and an adjacent parent block.

FIG. 7 is a schematic diagram showing the positional relationship between a child block with a Morton sequence number and an adjacent parent block.

FIG8 is a schematic diagram of the prediction tree structure.

Figure 9 is a diagram of the AVS codec framework.

FIG10 is a schematic flowchart of the encoding method provided in the first embodiment of the present application.

FIG11 is a schematic flowchart of a decoding method provided in the second embodiment of the present application.

FIG12 is a schematic flowchart of the encoding method provided in the second embodiment of the present application.

FIG. 13 is a schematic diagram of the structure of an encoder provided in one embodiment of the present application.

FIG14 is a schematic diagram of the structure of an encoder provided in another embodiment of the present application.

FIG15 is a schematic diagram of the structure of a decoder provided in one embodiment of the present application.

FIG16 is a schematic diagram of the structure of a decoder provided in another embodiment of the present application.

FIG17 is a schematic diagram of the structure of an encoder provided in another embodiment of the present application.

FIG18 is a schematic diagram of the structure of an encoder provided in another embodiment of the present application.

FIG. 19 is a schematic diagram of the structure of the encoding and decoding system provided in an embodiment of the present application.

DETAILED DESCRIPTION

In order to enable a more detailed understanding of the features and technical contents of the embodiments of the present application, the implementation of the embodiments of the present application is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

In the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

It should also be pointed out that the terms "first\second\third" involved in the embodiments of the present application are only used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

Point Cloud is a three-dimensional representation of the surface of an object. Point cloud (data) on the surface of an object can be collected through acquisition equipment such as photoelectric radar, lidar, laser scanner, and multi-view camera.

A point cloud is a set of irregularly distributed discrete points in space that express the spatial structure and surface properties of a three-dimensional object or scene. FIG1A shows a three-dimensional point cloud image and FIG1B shows a partial magnified view of the three-dimensional point cloud image. It can be seen that the point cloud surface is composed of densely distributed points.

Two-dimensional images have information expressed at each pixel point, and the distribution is regular, so there is no need to record its position information additionally; however, the distribution of points in point clouds in three-dimensional space is random and irregular, so it is necessary to record the position of each point in space in order to fully express a point cloud. Similar to two-dimensional images, each position in the acquisition process has corresponding attribute information, usually RGB color values, which reflect the color of the object; for point clouds, in addition to color information, the attribute information corresponding to each point is also commonly reflectance (reflectance) value, which reflects the surface material of the object. Therefore, point cloud data usually includes point location information and point attribute information. Among them, point location information can also be called point geometry information. For example, point geometry information can be the three-dimensional coordinate information (x, y, z) of the point. Point attribute information can include color information and/or reflectivity, etc. For example, reflectivity can be one-dimensional reflectivity information (r); color information can be information on any color space, or color information can also be three-dimensional color information, such as RGB information. Here, R represents red (Red, R), G represents green (Green, G), and B represents blue (Blue, B). For another example, the color information may be luminance and chrominance (YCbCr, YUV) information, where Y represents brightness (Luma), Cb (U) represents blue color difference, and Cr (V) represents red color difference.

For a point cloud obtained according to the principle of laser measurement, the points in the point cloud may include the three-dimensional coordinate information of the points and the reflectivity value of the points. For another example, for a point cloud obtained according to the principle of photogrammetry, the points in the point cloud may include the three-dimensional coordinate information of the points and the three-dimensional color information of the points. For another example, a point cloud obtained by combining the principles of laser measurement and photogrammetry may include the three-dimensional coordinate information of the points, the reflectivity value of the points and the three-dimensional color information of the points.

As shown in Figures 2A and 2B, a point cloud image and its corresponding data storage format are shown. Six viewing angles,Figure 2B consists of a file header information part and a data part.,The header information includes the data format, data representation type,,the total number of point cloud points, and the content represented by the point cloud.,For example, the point cloud is in the ".ply" format, represented by ASCII code,,the total number of points is 207242, and each point has three-dimensional,coordinate information (x,y,z) and three-dimensional color information (r,g,b).

Point clouds can be divided into the following categories according to the way they are obtained:

Static point cloud: the object is stationary, and the device that obtains the point cloud is also stationary;

Dynamic point cloud: The object is moving, but the device that obtains the point cloud is stationary;

Dynamic point cloud acquisition: The device used to acquire the point cloud is in motion.

For example, point clouds can be divided into two categories according to their usage:

Category 1: Machine perception point cloud, which can be used in autonomous navigation systems, real-time inspection systems, geographic information systems, visual sorting robots, disaster relief robots, etc.

Category 2: Point cloud perceived by the human eye, which can be used in point cloud application scenarios such as digital cultural heritage, free viewpoint broadcasting, 3D immersive communication, and 3D immersive interaction.

Point clouds can flexibly and conveniently express the spatial structure and surface properties of three-dimensional objects or scenes. Point clouds are obtained by directly sampling real objects, so they can provide a strong sense of reality while ensuring accuracy. Therefore, they are widely used, including virtual reality games, computer-aided design, geographic information systems, automatic navigation systems, digital cultural heritage, free viewpoint broadcasting, three-dimensional immersive remote presentation, and three-dimensional reconstruction of biological tissues and organs.

Point clouds can be collected mainly through the following methods: computer generation, 3D laser scanning, 3D photogrammetry, etc. Computers can generate point clouds of virtual three-dimensional objects and scenes; 3D laser scanning can obtain point clouds of static real-world three-dimensional objects or scenes, and can obtain millions of point clouds per second; 3D photogrammetry can obtain point clouds of dynamic real-world three-dimensional objects or scenes, and can obtain tens of millions of point clouds per second. These technologies reduce the cost and time cycle of point cloud data acquisition and improve the accuracy of data. The change in the way point cloud data is acquired makes it possible to acquire a large amount of point cloud data. With the growth of application demand, the processing of massive 3D point cloud data encounters bottlenecks in storage space and transmission bandwidth.

For example, taking a point cloud video with a frame rate of 30 frames per second (fps) as an example, the number of points in each point cloud frame is 700,000, and each point has coordinate information xyz (float) and color information RGB (uchar). The data volume of a 10s point cloud video is about 0.7 million × (4Byte × 3 + 1Byte × 3) × 30fps × 10s = 3.15GB, where 1Byte is 10bit; and a 1280 × 720 two-dimensional video with a YUV sampling format of 4:2:0 and a frame rate of 24fps, the data volume of 10s is about 1280 × 720 × 12bit × 24fps × 10s ≈ 0.33GB, and the data volume of a 10s two-view three-dimensional video is about 0.33 × 2 = 0.66GB. It can be seen that the data volume of a point cloud video far exceeds that of a two-dimensional video and a three-dimensional video of the same length. Therefore, in order to better realize data management, save server storage space, and reduce the transmission traffic and transmission time between the server and the client, point cloud compression has become a key issue in promoting the development of the point cloud industry.

That is to say, since the point cloud is a collection of massive points, storing the point cloud will not only consume a lot of memory, but also be inconvenient for transmission. There is also not enough bandwidth to support direct transmission of the point cloud at the network layer without compression. Therefore, the point cloud needs to be compressed.

At present, the point cloud coding framework that can compress point clouds can be the geometry-based point cloud compression (G-PCC) codec framework or the video-based point cloud compression (V-PCC) codec framework provided by the Moving Picture Experts Group (MPEG), or the AVS-PCC codec framework provided by the Audio Video Coding Standard (AVS). The G-PCC codec framework can be used to compress the first type of static point cloud and the third type of dynamically acquired point cloud, which can be based on the point cloud compression test platform (Test Model Compression 13, TMC13), and the V-PCC codec framework can be used to compress the second type of dynamic point cloud, which can be based on the point cloud compression test platform (Test Model Compression 2, TMC2). Therefore, the G-PCC codec framework is also called point cloud codec TMC13, and the V-PCC codec framework is also called point cloud codec TMC2.

An embodiment of the present application provides a network architecture of a point cloud encoding and decoding system including a decoding method and an encoding method. FIG3 is a schematic diagram of a network architecture of a point cloud encoding and decoding system provided by an embodiment of the present application.

As shown in Figure 3, the network architecture includes one or more electronic devices 13 to 1N and a communication network 01, wherein the electronic devices 13 to 1N can perform video interaction through the communication network 01. During the implementation process, the electronic device can be various types of devices with point cloud encoding and decoding functions. For example, the electronic device can include a mobile phone, a tablet computer, a personal computer, a personal digital assistant, a navigator, a digital phone, a video phone, a television, a sensor device, a server, etc., which is not limited by the embodiments of the present application. The decoder or encoder in the embodiment of the present application can be the above-mentioned electronic device. The electronic device in the embodiment of the present application has a point cloud encoding and decoding function, generally including a point cloud encoder (i.e., an encoder) and a point cloud decoder (i.e., a decoder).

The following introduces the AVS encoding and decoding framework.

In the point cloud AVS encoding framework, the geometric information of the point cloud and the attribute information corresponding to each point are encoded separately. During the encoding process, the geometric information of the point cloud is first transformed so that the point cloud is contained in a bounding box. Before the preprocessing process, it is decided whether to divide the entire point cloud sequence into multiple point cloud slices based on the parameter configuration. Each divided point cloud slice is treated as a single independent point cloud serial processing. The preprocessing process includes quantization and removal of duplicate points. Quantization mainly plays a role in scaling. Quantization and rounding make the geometric information of some points the same. For these duplicate points, it can be decided whether to remove the duplicate points according to the parameters. Next, the bounding box can be divided in the order of breadth-first traversal (such as based on octree/quadtree/binary tree), and then the placeholder code of each node is encoded. In the octree-based geometric coding framework, the bounding box is divided into sub-cubes in sequence, and the non-empty (containing points in the point cloud) sub-cubes are continued to be divided until the leaf node obtained by the division is a 1x1x1 unit cube. The division is stopped. In the case of geometric lossless coding, the number of points contained in the leaf node is encoded, and the encoding of the geometric octree is finally completed to generate a binary code stream. In the octree-based geometric decoding process, the decoding end obtains the placeholder code of each node by continuously parsing in the order of breadth-first traversal, and the nodes are continuously divided in sequence until the division is a 1x1x1 unit cube, and the number of points contained in each leaf node is parsed, and finally the geometric reconstructed point cloud information is restored.

There are two encoding methods in the current AVS geometric coding, one is octree encoding and the other is prediction tree encoding. The following introduces the two encoding methods respectively.

Octree encoding

If octree encoding is used, there are two context encoding models: context model 1 and context model 2. Context model 1 can be used for cat1-A and cat2 point cloud sequences; context model 2 can be used for cat1-B and cat3 sequences.

1. Context Model 1

The context model includes the sub-layer neighbor predictions of the current point and the neighbor predictions of the current point layer.

1) Sub-layer neighbor prediction of the current point

Under the octree breadth-first traversal partitioning method, the neighbor information that can be obtained when encoding the child node of the current point includes the neighbor child nodes in the three directions of left, front and bottom. The context model of the child node layer is designed as follows: for the child node layer to be encoded, find the occupancy of the three coplanar, three colinear, and one co-point nodes in the left, front and bottom direction of the same layer as the child node to be encoded, and the node in the negative direction of the dimension with the shortest node side length and the distance of two node side lengths from the current child node to be encoded. Taking the node with the shortest side length in the X dimension as an example, the reference node selected by each child node is shown in Figure 4. The dotted box node in Figure 4 is the current node, the gray node is the current child node to be encoded, and the solid box node is the reference node selected by each child node.

The occupancy of the 3 coplanar and 3 colinear nodes mentioned above and the nodes at the negative direction of the dimension with the shortest node side length and two node side lengths away from the current sub-node to be encoded (a total of 7 nodes) is considered in detail, and there are 2 ⁷ = 128 cases. If not all are unoccupied, there are 2 ⁷ -1 = 127 cases, and 1 context can be allocated for each case. If all 7 nodes are unoccupied, the occupancy of the common neighbor nodes is considered. There are 2 possibilities for the occupancy of the common neighbor nodes: occupied or unoccupied. A separate context can be allocated for the case where the common neighbor node is occupied. If the common neighbor is unoccupied, consider the occupancy of the neighbors at the current node layer to be described next. That is, the neighbors at the sub-node layer to be encoded correspond to a total of 127 + 2-1 = 128 contexts.

2) Neighbor prediction of the current node layer

If the eight reference nodes in the same layer of the subnode to be encoded are not occupied, the occupancy of the four groups of neighbors in the current node layer is considered as shown in Figure 5. The dotted frame node in Figure 5 is the current node, and the solid frame node is the neighbor node.

For the current node layer, the context may be determined according to steps 1 and 2 described below.

In step 1, first consider the three coplanar neighbors to the upper right of the current node. There are 2 ³ = 8 possible occupancy situations of the three coplanar neighbors to the upper right of the current node. For the cases where all of them are not occupied, a context is assigned to each. Considering that the child node to be encoded is located at the position of the current node, this group of neighbor nodes provides a total of (8-1) × 8 = 56 contexts. If none of the three coplanar neighbors to the upper right of the current point are occupied, then continue to consider the remaining three groups of neighbors at the current node level.

In step 2, the distance of the most recently occupied node from the current node is considered.

The corresponding relationship between neighbor node distribution and distance can be shown in Table 1.

Table 1 Correspondence between the current node layer occupancy and distance

As shown in Table 1, the distance has 3 values. One context is allocated to each of the 3 values, and considering the position of the sub-node to be encoded at the current node, there are 3×8=24 contexts in total.

So far, context model one has allocated a total of 128+56+24=208 contexts.

2. Context Model 2

The context model uses a two-layer context reference relationship configuration. As shown in formula (1), the first layer is the occupancy of the parent node of the current sub-block to be encoded (i.e., ctxIdxParent), and the second layer is the occupancy of the adjacent encoded blocks at the same depth as the current sub-block to be encoded (i.e., ctxIdxChild).

First, for each sub-block to be encoded, the ctxIdxChild of the second layer is as shown in formula (2): Indicates that the current sub-block Occupancy of the three coded sub-blocks with a distance of 1.
idx＝LUT[ctxIdxParent][ctxIdxChild] (1)

Secondly, for the first layer ctxIdxParent, for the relative positions of different sub-blocks, the adjacent parent blocks that are coplanar and colinear with them are found by table lookup, and the ctxIdxParent is calculated according to the occupancy of the adjacent parent blocks according to formula (3). As shown in Figure 6, each sub-graph shows the relative position relationship of the 6 adjacent parent blocks found by the i-th sub-block, including 3 coplanar parent blocks (P _i,0 ,P _i,1 ,P _i,2 ) and 3 colinear parent blocks (P _i,3 ,P _i,4 ,P _i,5 ). The position relationship between each sub-block and the adjacent parent block can be obtained by the method of Table 2. The numbers in Table 2 correspond to the Morton sequence in Figure 7. This method takes into account the different sub-block positions and the geometric center rotation symmetry. As can be seen from Figure 7, with the current block as the center, this method has a larger receptive field and can use up to 18 adjacent parent blocks that have been encoded around it. The method used in formula (3) is the combination of the occupancy of the 3 coplanar parent blocks and the sum of the number of occupancy of the 3 colinear parent blocks.

Therefore, the number of contexts used in this method is at most 2 ³ ×2 ⁵ =256.

Table 2 Relationship between child block i and its adjacent parent block j.

Prediction Tree Encoding

If prediction tree coding is used, the geometric information of the point cloud is first used at the encoding end to perform Morton code sorting, and then the geometric information of the point cloud is predicted and encoded using KD-Tree. Prediction tree coding is similar to a single chain structure, using the parent node to predict the geometric information of the child node. As shown in Figure 8, the prediction tree adopts a single chain structure: except for the only leaf node, each tree node has only one child node. Except for the root node of the prediction tree, which can be predicted by the default value, other nodes can be provided with geometric prediction values by their parent nodes.

During the multitree geometric coding process, the isolated point direct coding mode is effective when the current block satisfies the following three conditions at the same time.

Condition 1: The isolated point direct encoding mode identifier in the geometry header information is 1.

Condition 2: The current block contains only one point cloud data point.

Condition 3: The sum of the number of Morton code bits to be encoded for the points in the current block is greater than twice the number of directions that have not reached the minimum side length.

This branch is entered when all three conditions above are met. A flag is introduced to indicate whether the current node uses the isolated point coding mode. The flag can be entropy coded using a context. If the flag is true, the isolated point mode is used to directly encode the geometric coordinates of the point, and the octree division is terminated. If the flag is false, the occupancy code is encoded and the octree division continues.

In certain cases, this flag can be inferred to be False and not encoded. If the parent block of the current block already allows the use of isolated point coding mode, and the current block is the only child node of the parent block, then the current block must not contain isolated points. Therefore, under this condition, the bits for encoding the flag can be omitted.

After encoding the flag identification bit, since the current block only contains one point in a point cloud, the geometric coordinates of the point corresponding to the uncoded bits of the Morton code are directly encoded.

Assuming that the depth of the remaining coding bits of a point is nodeSizeLog2, the specific encoding process of the point is as follows:
for(int axisIdx＝0; axisIdx<3; ++axisIdx)
for(int mask＝(1<<nodeSizeLog2[axisIdx])>>1;mask;mask>>1)
encodePosBit(!!(pointPos[axisIdx]&mask));

After the geometric encoding is completed, the geometric information is reconstructed. At present, attribute encoding is mainly performed on color information and/or reflectivity information. First, determine whether to perform color space conversion. If color space conversion is performed, convert the color information from RGB color space to YUV. Color space. Then, the original point cloud is used to recolor the reconstructed point cloud so that the uncoded attribute information corresponds to the reconstructed geometric information. In color information encoding, it is divided into two modules: attribute prediction and attribute transformation. The attribute prediction process is as follows: first, the point cloud is reordered, and then differential prediction is performed. There are two reordering methods: Morton reordering and Hilbert reordering. For cat1A sequence and cat2 sequence, Hilbert reordering is performed; for cat1B sequence and cat3 sequence, Morton reordering is performed. The attribute prediction of the sorted point cloud is performed using a differential method, and finally the prediction residual is quantized and entropy encoded to generate a binary code stream. The attribute transformation process is as follows: first, wavelet transform is performed on the point cloud attributes, and the transform coefficients are quantized; secondly, the attribute reconstruction value is obtained by inverse quantization and inverse wavelet transform; then the difference between the original attribute and the attribute reconstruction value is calculated to obtain the attribute residual and quantize it; finally, the quantized transform coefficients and attribute residuals are entropy encoded to generate a binary code stream. Figure 9 shows the AVS codec framework diagram.

The following is an introduction to the general test conditions of AVS-PCC.

There are 4 test conditions:

Condition 1: The geometric position is limitedly lossy and the attributes are lossy;

Condition 2: The geometric position is lossless, but the attributes are lossy;

Condition 3: lossless geometry and limited loss of attributes; and

Condition 4: The geometric position and attributes are lossless.

The general test sequences include five categories: Cat1A, Cat1B, Cat1C, Cat2-frame and Cat3. Cat1A and Cat2-frame point clouds only contain reflectance attribute information, Cat1B and Cat3 point clouds only contain color attribute information, and Cat1C point cloud contains both color and reflectance attribute information.

There are many technical routes for attribute encoding, and they can be distinguished by the algorithm used for attribute compression. The following introduces several commonly used technical routes.

Technical route 1: prediction branch, attribute compression adopts intra-frame prediction-based method

At the encoding end, the points in the point cloud are processed in a certain order (the original acquisition order of the point cloud, the Morton order, the Hilbert order, etc.). During the processing, the prediction algorithm is first used to obtain the attribute prediction value, and the attribute residual is obtained according to the attribute value and the attribute prediction value. Then, the attribute residual is quantized to generate the quantized residual, and finally the quantized residual is encoded.

At the decoding end, the points in the point cloud are processed in a certain order (the original acquisition order of the point cloud, the Morton order, the Hilbert order, etc.). During the processing, the prediction algorithm is first used to obtain the attribute prediction value, then the decoding is performed to obtain the quantized residual, and then the quantized residual is dequantized, and finally the attribute reconstruction value is obtained based on the attribute prediction value and the dequantized residual.

Technical route 2: Prediction transformation branch - limited resources, attribute compression uses a method based on intra-frame prediction and discrete cosine transform (DCT) transformation.

In technical route 2, when encoding the quantized transform coefficients, there is a limit of a maximum number of points X (eg, 4096), that is, at most every X points is encoded as a group.

At the encoding end, the points in the point cloud are processed in a certain order (the original acquisition order of the point cloud, Morton order, Hilbert order, etc.). During the processing, the entire point cloud is first divided into several small groups with a maximum length of Y (such as 2), and then these small groups are combined into several large groups (the number of points in each large group does not exceed X, such as 4096). Next, the prediction algorithm is used to obtain the attribute prediction value, and the attribute residual is obtained based on the attribute value and the attribute prediction value. Then, the attribute residual is DCT transformed in small groups to generate transformation coefficients, and then the transformation coefficients are quantized to generate quantized transformation coefficients, and finally the quantized transformation coefficients are encoded in large groups.

At the decoding end, the points in the point cloud are processed in a certain order (the original acquisition order of the point cloud, Morton order, Hilbert order, etc.). During the processing, the entire point cloud is first divided into several small groups with a maximum length of Y (such as 2), and then these small groups are combined into several large groups (the number of points in each large group does not exceed X, such as 4096). Next, the quantized transform coefficients are decoded in large groups, and then the prediction algorithm is used to obtain the attribute prediction value. The quantized transform coefficients are then dequantized and inversely transformed in small groups. Finally, the attribute reconstruction value is obtained based on the attribute prediction value and the dequantized and inversely transformed coefficients.

Technical route 3: predictive transformation branch - resource-unlimited

In technical route 3, attribute compression adopts a method based on intra-frame prediction and DCT transformation, and when encoding the quantized transform coefficients, there is no limit on the maximum number of points X, that is, all coefficients can be encoded together.

At the encoding end, the points in the point cloud are processed in a certain order (the original acquisition order of the point cloud, Morton order, Hilbert order, etc.). During the processing, the entire point cloud is first divided into several small groups with a maximum length of Y (such as 2), and then the prediction algorithm is used to obtain the attribute prediction The attribute residual is obtained according to the attribute value and the attribute prediction value, the attribute residual is transformed by DCT in small groups to generate transformation coefficients, the transformation coefficients are quantized to generate quantized transformation coefficients, and finally the quantized transformation coefficients of the entire point cloud are encoded.

At the decoding end, the points in the point cloud are processed in a certain order (the original acquisition order of the point cloud, the Morton order, the Hilbert order, etc.). During the processing, the entire point cloud is first divided into several small groups with a maximum length of Y (such as 2), and the quantized transformation coefficients of the entire point cloud are obtained by decoding. Then, the prediction algorithm is used to obtain the attribute prediction value, and then the quantized transformation coefficients are dequantized and inversely transformed in groups. Finally, the attribute reconstruction value is obtained based on the attribute prediction value and the dequantized and inversely transformed coefficients.

Technical route 4: Multi-layer transformation branch, attribute compression adopts a method based on multi-layer wavelet transform

At the encoding end, the entire point cloud is subjected to multi-layer wavelet transform to generate transform coefficients. Then, the transform coefficients are quantized to generate quantized transform coefficients. Finally, the quantized transform coefficients of the entire point cloud are encoded.

At the decoding end, the decoding obtains the quantized transform coefficients of the entire point cloud. Then, the quantized transform coefficients are dequantized and inversely transformed to obtain the attribute reconstruction value.

In related point cloud coding technologies (such as AVS-PCC), after completing the geometric coding, the encoding end will sort the attribute information of the duplicate points (in ascending order). For example, if the attribute information of the current point cloud is color information, the color information of the duplicate points can be sorted. If the attribute information of the duplicate points only contains reflectivity information, the attribute information of the duplicate points can be sorted. If the above design is adopted, when encoding the attribute information of the duplicate points, it will be assumed that the attribute information of the duplicate points has been sorted in ascending order, so there is no need to encode the sign bit of the attribute residual of the current point, thereby improving the encoding performance of the point cloud attribute information.

If the point cloud has multiple attribute information, the related technology will sort the multiple attribute information of the duplicate points separately, and this sorting method may cause attribute encoding loss. Assume that the current point cloud includes 3 duplicate points: duplicate point 1, duplicate point 2, and duplicate point 3. The Y component of the color information of duplicate point 1 is 14, and the reflectivity information is 8; the Y component of the color information of duplicate point 2 is 15, and the reflectivity information is 10; the Y component of the color information of duplicate point 1 is 16, and the reflectivity information is 9. According to the separate sorting algorithm provided by the related technology, the sorting results of the Y component of the color information are 14, 15, 16, and the sorting results of the reflectivity information are 8, 9, 10. By comparing the two sorting results, it can be found that the correspondence between the multiple attribute information in the original point cloud is destroyed. The Y component of duplicate point 2 is 15, and the reflectivity information is 10. After sorting, the correspondence of 15->10 in the duplicate point 2 becomes 15->9. This change in correspondence will cause subsequent attribute encoding loss. It can be seen that, whether for lossy coding or no coding, the related technology of separately sorting multiple attribute information of repeated points may introduce additional losses, thereby reducing the encoding and decoding performance.

In addition, for multiple attribute information, related point cloud coding technologies (such as AVS-PCC) sometimes introduce interdependence between different attribute information when encoding multiple attributes in order to further improve the efficiency of point cloud attribute coding. For example, if the attribute information includes color information and reflectivity information, the reflectivity information can be encoded based on the reconstructed color information. The sorting scheme of multiple attribute information of repeated points mentioned above will destroy the correlation between attribute information, and therefore will also cause coding loss (or inability to achieve lossless attribute coding) in the coding scheme where multiple attribute information depends on each other.

In response to the above problems, the embodiments of the present application are described in detail below.

First embodiment:

The first embodiment of the present application provides an encoding method, comprising: determining a set of repeated points in a point cloud to be encoded; wherein the repeated points in the repeated point set include multiple attribute information; and sorting the repeated points in the repeated point set according to the multiple attribute information.

Different from the related art, the embodiment of the present application does not sort the multiple attribute information of the duplicate points separately, but sorts the multiple attribute information of the duplicate points uniformly based on the first attribute information, thereby avoiding destroying the relevance between the multiple attribute information, reducing the loss of attribute encoding, and improving encoding performance. The encoding method provided in the embodiment of the present application can be applied to lossless encoding scenarios, thereby helping to achieve lossless encoding of attribute information.

FIG10 is a schematic flow chart of the encoding method provided in the first embodiment of the present application. The method of FIG10 can be applied to an encoder. The encoding method can refer to a method for encoding attribute information (such as color information) of a point cloud. The following is a detailed example of each step of FIG10.

In step S1010, a set of repeated points of the point cloud to be encoded is determined.

The point cloud to be encoded may be all points in the point cloud, or may be part of the points in the point cloud. For example, the point cloud to be encoded may refer to points that are relatively concentrated in space.

In some embodiments, the above-mentioned determination of the set of repeated points in the point cloud to be encoded may include: determining the set of repeated points in the point cloud to be encoded according to geometric information of the point cloud to be encoded.

In some embodiments, the repeated points in the repeated point set may include points with the same geometric information in the point cloud to be encoded. The geometric information may be, for example, reconstructed geometric information of the points.

In some embodiments, if the geometric information of two points is very close, or the distance determined based on the geometric information is very close, the two points may also be determined as duplicate points.

In some embodiments, the distance between points in the point cloud to be encoded can be determined based on the geometric information of the point cloud to be encoded. Then, based on the distance between points in the point cloud to be encoded, points with the same or similar distance can be determined to form a set of repeated points.

For example, the Morton code or Hilbert code of the points in the point cloud to be encoded can be determined; then, the points with the same or similar Morton code or Hilbert code are grouped into a set of repeated points. In other words, when determining repeated points, the repeated points can be determined directly through geometric coordinate information, or the geometric coordinates can be first converted into Morton code or Hilbert code, and then the set of repeated points can be determined based on the Morton code or Hilbert code.

The repeated points in the repeated point set may include multiple attribute information, for example, the repeated points may include color information and reflectivity information at the same time.

In step S1020, the repeated points in the repeated point set are sorted according to various attribute information.

In some embodiments, the above-mentioned sorting of the repeated points in the repeated point set according to the various attribute information may be replaced by sorting the attribute information of the repeated points in the repeated point set in units of points.

In some embodiments, the above-mentioned sorting of the repeated points in the repeated point set according to multiple attribute information can be replaced by sorting the repeated points in the repeated point set according to at least one attribute information (such as the first attribute information mentioned later).

In some embodiments, the above-mentioned sorting of duplicate points in the duplicate point set according to multiple attribute information can be replaced by: sorting the duplicate points in the duplicate point set while keeping the association relationship between the multiple attribute information of the duplicate points in the duplicate point set unchanged; or sorting the duplicate points in the duplicate point set so that the association relationship between the multiple attribute information of the duplicate points in the duplicate point set remains unchanged.

The first attribute information may be any one of a plurality of attribute information. For example, if the repeated point includes color information and reflectivity information, the first attribute information may refer to color information or reflectivity information.

In some embodiments, the first attribute information may be the attribute information that is preferentially encoded among the multiple attribute information. For example, if the encoding order of the multiple attribute information of the repeated point is to encode the color information first and then the reflectivity information, the first attribute information may be the color information. For another example, if the encoding order of the multiple attribute information of the repeated point is to encode the reflectivity information first and then the color information, the first attribute information may be the reflectivity information. By setting the first attribute information as the attribute information that is preferentially encoded among the multiple attribute information, the sorting scheme of the repeated points in the repeated point set can be adapted to the cross-attribute encoding scheme.

In some embodiments, if the first attribute information is color information, sorting the duplicate points in the duplicate point set according to the multiple attribute information may include: sorting the duplicate points in the duplicate point set according to the first color component of the first attribute information. The first color component mentioned here may be a color component that is preferentially encoded in the attribute information of the duplicate point.

In some embodiments, the above-mentioned sorting of the duplicate points in the duplicate point set according to the multiple attribute information may include: sorting the duplicate points in the duplicate point set according to a first sorting method; wherein the first sorting method is to sort according to the first attribute information in the multiple attribute information first, and then sort according to the second attribute information in the multiple attribute information. For example, the duplicate points in the duplicate point set are sorted according to the first attribute information first, and if the duplicate point set includes at least two duplicate points with the same first attribute information, the at least two duplicate points are sorted according to the second attribute information of the at least two duplicate points.

As an example, the first attribute information may be color information, and the second attribute information may be reflectivity information. That is, the duplicate points in the duplicate point set may be sorted first according to the color information, and then the duplicate points in the duplicate point set may be sorted according to the reflectivity information (i.e., when the color information is the same, the duplicate points in the duplicate point set may be sorted according to the reflectivity information).

As another example, the first attribute information may be reflectance information, and the second attribute information may be color information. That is, the duplicate points in the duplicate point set may be sorted first according to the reflectance information, and then the duplicate points in the duplicate point set may be sorted according to the color information (i.e., when the reflectance information is the same, the duplicate points in the duplicate point set may be sorted according to the color information).

In some embodiments, a parameter (hereinafter referred to as the first parameter) may be introduced, and the first parameter may be used to indicate whether to perform repeated point encoding. Alternatively, the first parameter is used to control repeated point encoding. Alternatively, the first parameter may be used to indicate whether to perform repeated point encoding when the point cloud has multiple attribute information. By introducing the first parameter, the repeated point encoding process may be flexibly turned on or off. For example, if the repeated point contains only one type of attribute information, it may be indicated to perform repeated point encoding (because performing repeated point encoding at this time will not introduce attribute encoding loss); if the repeated point contains multiple types of attribute information, it may be indicated not to perform repeated point encoding (because performing repeated point encoding at this time will introduce attribute encoding loss). It can be seen that the introduction of the first parameter helps the attribute encoding to achieve lossless encoding.

The first parameter may be a high-level syntax element. In some embodiments, the first parameter may be called, for example, eligible_duplicate_pred.

In some embodiments, the first parameter may include a first value and a second value. If the value of the first parameter is the first value, it is determined that repeated point coding is performed. If the value of the first parameter is the second value (different from the first value), it is determined that repeated point coding is not performed.

The above-mentioned repeated point coding may include: sorting based on the attribute information of the repeated points. That is, when the value of the first parameter is the first value, the attribute information of the repeated points may be sorted; when the value of the first parameter is the second value, the attribute information of the repeated points may not be sorted. Sort.

In some embodiments, if the repeated point contains only one kind of attribute information, the value of the first parameter may be set to the first value. If the repeated point contains multiple kinds of attribute information at the same time, the value of the first parameter may be set to the second value.

In some embodiments, the first value and the second value may be in parameter form. Alternatively, the first value and the second value may also be in digital form.

In some embodiments, the first parameter may be a parameter written into the bitstream. For example, the first parameter may be a parameter in an Adaptation Parameter Set (APS).

Exemplarily, the first value may be set to 1 and the second value may be set to 0; or, the first value may be set to 0 and the second value may be set to 1; or, the first value may be set to true and the second value may be set to false; or, the first value may be set to false and the second value may be set to true.

Taking the first parameter as a parameter written into the bit stream as an example, assuming that the first value of the first parameter is 0 and the second value is 1, if the value of the first parameter is 0, it can be determined that repeated point encoding is not performed, that is, there is no need to execute the encoding method described in the embodiment of the present application; if the value of the first parameter is 1, it can be determined that repeated point encoding is performed, that is, the encoding method described in the embodiment of the present application is executed.

In some embodiments, the method of Figure 10 may also include: if the current point to be encoded is a repeated point, determining the encoding method of the sign bit of the residual of the second attribute component of the current point based on the residual of the first attribute component of the current point; wherein the first attribute component and the second attribute component belong to the same attribute information among multiple attribute information; or, the first attribute component and the second attribute component belong to different attribute information among multiple attribute information.

In the encoding order of the attribute components of the current point, the first attribute component is sorted before the second attribute component.

In some embodiments, in the encoding order, the first attribute component precedes the second attribute component.

Taking the first attribute component and the second attribute component as different color components of the current point as an example, the first attribute component can be the first color component in the color information, and the second attribute component can be the second color component in the color information. That is, at the encoding end, the first color component can be encoded to determine the residual of the first color component; then, the encoding method of the sign bit of the residual of the second color component can be determined based on the residual of the first color component (the value thereof).

For example, if the encoding end performs encoding in the order of RGB, the first attribute component may be an R component, and the second attribute component may be a G component.

For another example, if the encoding end performs encoding in the order of GRB, the first attribute component may be a G component, and the second attribute component may be an R component.

For another example, if the encoding end performs encoding in the order of YUV, the first attribute component may be a Y component, and the second attribute component may be a U component.

For another example, if the encoding end performs encoding in the order of UYV, the first attribute component may be a U component, and the second attribute component may be a Y component.

In some embodiments, the first attribute component includes all attribute components that precede the second attribute component in coding order.

Taking the first attribute component and the second attribute component as different color components of the current point as an example, the first attribute component may include the first color component and the second color component in the color information, and the second attribute component may be the third color component in the color information. That is, at the encoding end, the first color component and the second color component may be encoded to determine the residual of the first color component and the second color component; then, based on the residual of the first color component (the value thereof) and the residual of the second color component (the value thereof), the encoding method of the sign bit of the residual of the third color component may be determined.

For example, if the encoding end performs encoding in the order of RGB, the first attribute component may include an R component and a G component, and the second attribute component may be a B component.

For another example, if the encoding end performs encoding in the order of GRB, the first attribute component may include a G component and an R component, and the second attribute component may be a B component.

For another example, if the encoding end performs encoding in the order of YUV, the first attribute component may include a Y component and a U component, and the second attribute component may be a V component.

For another example, if the encoding end performs encoding in the order of UYV, the first attribute component may include a U component and a Y component, and the second attribute component may be a V component.

In some embodiments, one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information.

For example, if the encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the color information and then encode the attribute components corresponding to the reflectivity information, the first attribute component may be the attribute component corresponding to the color information, and the second attribute component may be the attribute component corresponding to the reflectivity information.

As an example, the encoding order of the attribute components of the current point is to encode RGB first and then encode the reflectivity information, so the first attribute component may include RGB, and the second attribute component may be the reflectivity information.

As another example, the encoding order of the attribute components of the current point is to encode YUV first and then encode reflectivity information. The quantity may include YUV, and the second attribute component may be reflectivity information.

For another example, if the encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the reflectivity information and then encode the attribute components corresponding to the color information, then the first attribute component may be the attribute component corresponding to the reflectivity information, and the second attribute component may be the attribute component corresponding to the color information.

As an example, the encoding order of the attribute components of the current point is to encode the reflectance information first and then encode RGB, so the first attribute component may be the reflectance information, and the second attribute component may include RGB.

As another example, the encoding order of the attribute components of the current point is to encode the reflectivity information first and then encode the YUV, so the first attribute component may be the reflectivity information, and the second attribute component may include the YUV.

In some embodiments, the above-mentioned method of determining the encoding method of the sign bit of the residual of the second attribute component of the current point based on the residual of the first attribute component of the current point may include: if the residual of the first attribute component of the current point is 0, determining not to encode the sign bit of the residual of the second attribute component.

Taking the encoding order of the current point as RGB as an example, the first attribute component can be the R component, and the second attribute component can be the G component. If the residual of the R component is 0, the sign bit of the residual of the G component may not be encoded (the residual of the R component is 0, which means that there are multiple repeated points with the same R component. At this time, the G components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the G component).

Taking the encoding order of the current point as RGB as an example, the first attribute component may include an R component and a G component, and the second attribute component may be a B component. If the residual of the R component and the residual of the G component are both 0, the sign bit of the residual of the B component may not be encoded (the residual of the R component and the residual of the G component are both 0, indicating that there are multiple repeated points with the same R component and G component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the B component).

Taking the encoding order of the current point as GRB as an example, the first attribute component can be the G component, and the second attribute component can be the R component. If the residual of the G component is 0, the sign bit of the residual of the R component may not be encoded (the residual of the G component is 0, which means that there are multiple repeated points with the same G component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the B component).

Taking the encoding order of the current point as GRB as an example, the first attribute component may include a G component and an R component, and the second attribute component may be a B component. If the residual of the G component and the residual of the R component are both 0, the sign bit of the residual of the B component may not be encoded (the residual of the G component and the residual of the R component are both 0, indicating that there are multiple repeated points with the same G component and R component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the B component).

Taking the encoding order of the current point as an example of first encoding RGB and then encoding the reflectivity information, the first attribute component may include R component, G component and B component, and the second attribute component may be the reflectivity information. If the residuals of the R component, G component and B component are all 0, the sign bit of the residual of the reflectivity information may not be encoded (the residuals of the R component, G component and B component are all 0, indicating that there are multiple repeated points with the same R component, G component and B component. At this time, the reflectivity information of the multiple repeated points is in ascending order, so there is no need to encode the sign bit of the residual of the reflectivity information).

Taking the encoding order of the current point as first encoding GRB and then encoding the reflectivity information as an example, the first attribute component may include G component, R component and B component, and the second attribute component may be the reflectivity information. If the residuals of the G component, R component and B component are all 0, the sign bit of the residual of the reflectivity information may not be encoded (the residuals of the G component, R component and B component are all 0, indicating that there are multiple repeated points with the same G component, R component and B component. At this time, the reflectivity information of the multiple repeated points is in ascending order, so there is no need to encode the sign bit of the residual of the reflectivity information).

Taking the encoding order of the current point as first encoding the reflectance information and then encoding RGB as an example, the first attribute component can be the reflectance information, and the second attribute component can be the R component. If the residual of the reflectance information is 0, the sign bit of the residual of the R component may not be encoded (the residual of the reflectance information is 0, indicating that there are multiple repeated points with the same reflectance information. At this time, the R components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the R component).

Taking the encoding order of the current point as first encoding the reflectivity information and then encoding GRB as an example, the first attribute component can be the reflectivity information, and the second attribute component can be the G component. If the residual of the reflectivity information is 0, the sign bit of the residual of the G component may not be encoded (the residual of the reflectivity information is 0, indicating that there are multiple repeated points with the same reflectivity information. At this time, the G components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the G component).

In some embodiments, if the current point is not a duplicate point, the sign bits of the residuals of the various attribute components of the current point are encoded. If the current point is not a duplicate point, the sign bits of the various components of the color residual of the current point may be positive or negative. In this case, encoding the sign bits of the various components of the color residual of the current point can ensure the accuracy of the encoding.

In some embodiments, the method of FIG. 10 may further include: determining prediction information of the attribute information of the current point; and determining a color residual of the current point according to the prediction information of the attribute information of the current point.

The prediction information of the attribute information of the current point can be determined based on the reconstructed attribute information of the prediction reference point of the current point. The selection method of the prediction reference point of the current point can be determined based on the type of the current point. For example, if the current point is not a repeated point, it can be based on a certain distance (such as Manhattan distance) to determine the K neighboring points of the current point (K is a positive integer), and then use the K neighboring points as prediction reference points to perform weighted prediction on the attribute information of the current point. For another example, if the current point is a repeated point, the first M repeated points of the current point can be determined as prediction reference points, and then the predicted information of the attribute information of the current point is determined based on the reconstructed attribute information of the first M repeated points; where M is a positive integer. As an example, the value of M can be 1, that is, the attribute information of the current point can be differentially predicted based on the reconstructed attribute information of the previous repeated point of the current point.

In some embodiments, the method of FIG. 10 may further include: quantizing the color residual of the current point to determine the quantized residual of the current point; encoding the quantized residual, and writing the obtained coded bits into the bitstream.

Second embodiment:

The second embodiment of the present application also provides a decoding method, including: determining the value of a first parameter; if the value of the first parameter is a first value, performing a repeated point decoding operation; wherein the value of the first parameter includes a first value and a second value, the first value is used to indicate that the repeated point decoding operation is performed, and the second value is used to indicate that the repeated point decoding operation is not performed.

The second embodiment of the present application provides a coding method, including: determining whether to perform a repeated point coding operation; determining a value of a first parameter based on a determination result; encoding the value of the first parameter, and writing the obtained coded bits into a bit stream; wherein the value of the first parameter includes a first value and a second value, the first value is used to indicate that the repeated point coding operation is performed, and the second value is used to indicate that the repeated point coding operation is not performed.

The above-mentioned repeated point encoding operation may include: sorting based on the attribute information of the repeated points. That is, when the value of the first parameter is the first value, the attribute information of the repeated points may be sorted; when the value of the first parameter is the second value, the attribute information of the repeated points may not be sorted.

The second embodiment of the present application controls whether to perform the repeated point coding operation based on the first parameter, so that the repeated point coding operation can be flexibly turned on or off according to actual conditions.

FIG11 is a schematic flow chart of a decoding method provided in the second embodiment of the present application. The method of FIG11 can be applied to a decoder. The decoding method can refer to a method for decoding attribute information (such as color information) of a point cloud. The following is a detailed example of each step of FIG11.

In step S1110, the code stream is parsed to determine the value of the first parameter.

The first parameter may be used to indicate whether to perform repeated point decoding. Alternatively, the first parameter may be used to control repeated point decoding. Alternatively, the first parameter may be used to indicate whether to perform repeated point decoding when the point cloud to be decoded has multiple attribute information.

The point cloud to be decoded may be all points in the point cloud, or may be part of the points in the point cloud. For example, the point cloud to be decoded may refer to points that are relatively concentrated in space.

The first parameter may be a high-level syntax element. In some embodiments, the first parameter may be called, for example, eligible_duplicate_pred.

In some embodiments, the first parameter may be a parameter written into the bitstream. For example, the first parameter may be a parameter in an Adaptation Parameter Set (APS).

In step S1120, if the value of the first parameter is the first value, a repeated point decoding operation is performed.

The first parameter may also include a second value. If the value of the first parameter is the second value (different from the first value), it is determined that repeated point decoding is not performed.

In some embodiments, if the repeated point contains only one kind of attribute information, the value of the first parameter may be set to the first value. If the repeated point contains multiple kinds of attribute information at the same time, the value of the first parameter may be set to the second value.

In some embodiments, the first value and the second value may be in parameter form. Alternatively, the first value and the second value may also be in digital form.

Exemplarily, the first value may be set to 1 and the second value may be set to 0; or, the first value may be set to 0 and the second value may be set to 1; or, the first value may be set to true and the second value may be set to false; or, the first value may be set to false and the second value may be set to true.

Taking the first parameter as a parameter written into the bitstream as an example, assuming that the first value of the first parameter is 0 and the second value is 1, if the value of the first parameter is 0, it can be determined that the duplicate point decoding operation is not performed; if the value of the first parameter is 1, it can be determined that the duplicate point decoding operation is performed.

In some embodiments, the method of Figure 11 may also include: if the current point to be decoded is a repeated point, determining the decoding method of the sign bit of the residual of the second attribute component of the current point based on the residual of the first attribute component of the current point; wherein the first attribute component and the second attribute component belong to the same attribute information among multiple attribute information; or, the first attribute component and the second attribute component belong to different attribute information among multiple attribute information.

The current point may refer to a point in the point cloud that is currently to be decoded.

In the decoding order of the attribute components at the current point, the first attribute component is sorted before the second attribute component.

In some embodiments, in decoding order, the first attribute component precedes the second attribute component.

Taking the first attribute component and the second attribute component as different color components of the current point as an example, the first attribute component can be color information The first color component in the color information, the second attribute component may be the second color component in the color information. That is, at the decoding end, the first color component may be decoded to determine the residual of the first color component; then, the decoding method of the sign bit of the residual of the second color component may be determined based on the residual of the first color component (the value thereof).

For example, if the decoding end performs decoding in the order of RGB, the first attribute component may be an R component, and the second attribute component may be a G component.

For another example, if the decoding end performs decoding in the order of GRB, the first attribute component may be a G component, and the second attribute component may be an R component.

For another example, if the decoding end performs decoding according to the order of YUV, the first attribute component may be a Y component, and the second attribute component may be a U component.

For another example, if the decoding end performs decoding in the order of UYV, the first attribute component may be a U component, and the second attribute component may be a Y component.

In some embodiments, the first attribute component includes all attribute components that precede the second attribute component in decoding order.

Taking the first attribute component and the second attribute component as different color components of the current point as an example, the first attribute component may include the first color component and the second color component in the color information, and the second attribute component may be the third color component in the color information. That is, at the decoding end, the first color component and the second color component may be first decoded to determine the residual of the first color component and the second color component; then, based on the residual of the first color component (the value thereof) and the residual of the second color component (the value thereof), the decoding method of the sign bit of the residual of the third color component may be determined.

For example, if the decoding end performs decoding in the order of RGB, the first attribute component may include an R component and a G component, and the second attribute component may be a B component.

For another example, if the decoding end performs decoding in the order of GRB, the first attribute component may include a G component and an R component, and the second attribute component may be a B component.

For another example, if the decoding end performs decoding in the order of YUV, the first attribute component may include a Y component and a U component, and the second attribute component may be a V component.

For another example, if the decoding end performs decoding in the order of UYV, the first attribute component may include a U component and a Y component, and the second attribute component may be a V component.

In some embodiments, one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information.

For example, if the decoding order of the attribute components of the current point is to first decode the attribute components corresponding to the color information and then decode the attribute components corresponding to the reflectivity information, the first attribute component may be the attribute component corresponding to the color information and the second attribute component may be the attribute component corresponding to the reflectivity information.

As an example, the decoding order of the attribute components of the current point is to first decode RGB and then decode the reflectivity information. Then, the first attribute component may include RGB, and the second attribute component may be the reflectivity information.

As another example, the decoding order of the attribute components of the current point is to first decode YUV and then decode the reflectivity information. Then, the first attribute component may include YUV, and the second attribute component may be the reflectivity information.

For another example, if the decoding order of the attribute components of the current point is to first decode the attribute components corresponding to the reflectance information and then decode the attribute components corresponding to the color information, the first attribute component may be the attribute component corresponding to the reflectance information, and the second attribute component may be the attribute component corresponding to the color information.

As an example, the decoding order of the attribute components of the current point is to first decode the reflectance information and then decode RGB, so the first attribute component may be the reflectance information, and the second attribute component may include RGB.

As another example, the decoding order of the attribute components of the current point is to first decode the reflectivity information and then decode the YUV, so the first attribute component may be the reflectivity information, and the second attribute component may include the YUV.

In some embodiments, the above-mentioned method of determining the decoding method of the sign bit of the residual of the second attribute component of the current point based on the residual of the first attribute component of the current point may include: if the residual of the first attribute component of the current point is 0, determining not to decode the sign bit of the residual of the second attribute component.

Taking the decoding order of the current point as RGB as an example, the first attribute component can be the R component, and the second attribute component can be the G component. If the residual of the R component is 0, the sign bit of the residual of the G component does not need to be decoded (the residual of the R component is 0, which means that there are multiple repeated points with the same R component. At this time, the G components of the multiple repeated points are in ascending order, so there is no need to decode the sign bit of the residual of the G component).

Taking the decoding order of the current point as RGB as an example, the first attribute component may include an R component and a G component, and the second attribute component may be a B component. If the residual of the R component and the residual of the G component are both 0, the sign bit of the residual of the B component may not be decoded (the residual of the R component and the residual of the G component are both 0, indicating that there are multiple repeated points with the same R component and G component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to decode the sign bit of the residual of the B component).

Taking the decoding order of the current point as GRB as an example, the first attribute component can be the G component, and the second attribute component can be the R component. If the residual of the G component is 0, the sign bit of the residual of the R component does not need to be decoded (the residual of the G component is 0, which means that there are multiple repeated points with the same G component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to decode the sign bit of the residual of the B component).

Taking the decoding order of the current point as GRB as an example, the first attribute component may include a G component and an R component, and the second attribute component may be a B component. If the residual of the G component and the residual of the R component are both 0, the sign bit of the residual of the B component may not be decoded (the residual of the G component and the residual of the R component are both 0, indicating that there are multiple repeated points with the same G component and R component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to decode the sign bit of the residual of the B component).

Taking the decoding order of the current point as first decoding RGB and then decoding the reflectivity information as an example, the first attribute component may include R component, G component and B component, and the second attribute component may be the reflectivity information. If the residuals of the R component, G component and B component are all 0, the sign bit of the residual of the reflectivity information may not be decoded (the residuals of the R component, G component and B component are all 0, indicating that there are multiple repeated points with the same R component, G component and B component. At this time, the reflectivity information of the multiple repeated points is presented in ascending order, so there is no need to decode the sign bit of the residual of the reflectivity information).

Taking the decoding order of the current point as first decoding GRB and then decoding the reflectivity information as an example, the first attribute component may include G component, R component and B component, and the second attribute component may be the reflectivity information. If the residuals of the G component, R component and B component are all 0, the sign bit of the residual of the reflectivity information may not be decoded (the residuals of the G component, R component and B component are all 0, indicating that there are multiple repeated points with the same G component, R component and B component. At this time, the reflectivity information of the multiple repeated points is presented in ascending order, so there is no need to decode the sign bit of the residual of the reflectivity information).

Taking the decoding order of the current point as first decoding the reflectance information and then decoding RGB as an example, the first attribute component may be the reflectance information, and the second attribute component may be the R component. If the residual of the reflectance information is 0, the sign bit of the residual of the R component may not be decoded (the residual of the reflectance information is 0, indicating that there are multiple repeated points with the same reflectance information. At this time, the R components of the multiple repeated points are in ascending order, so there is no need to decode the sign bit of the residual of the R component).

Taking the decoding order of the current point as first decoding the reflectivity information and then decoding GRB as an example, the first attribute component may be the reflectivity information, and the second attribute component may be the G component. If the residual of the reflectivity information is 0, the sign bit of the residual of the G component may not be decoded (the residual of the reflectivity information is 0, indicating that there are multiple repeated points with the same reflectivity information. At this time, the G components of the multiple repeated points are in ascending order, so there is no need to decode the sign bit of the residual of the G component).

In some embodiments, if the current point is not a duplicate point, the sign bits of the residuals of the various attribute components of the current point are decoded. If the current point is not a duplicate point, the sign bits of the various components of the color residual of the current point may be positive or negative. In this case, decoding the sign bits of the various components of the color residual of the current point can ensure the accuracy of decoding.

In some embodiments, the method of FIG. 11 may further include: determining the reconstructed attribute information of the current point according to the prediction information and the attribute residual of the attribute information of the current point.

The prediction information of the attribute information of the current point can be determined based on the reconstructed attribute information of the prediction reference point of the current point. The selection method of the prediction reference point of the current point can be determined based on the type of the current point. For example, if the current point is not a duplicate point, the K neighbor points (K is a positive integer) of the current point can be determined based on a certain distance (such as Manhattan distance), and then the K neighbor points are used as prediction reference points to perform weighted prediction on the attribute information of the current point. For another example, if the current point is a duplicate point, the first M duplicate points of the current point can be determined as prediction reference points, and then the prediction information of the attribute information of the current point is determined based on the reconstructed attribute information of the first M duplicate points; wherein M is a positive integer. As an example, the value of M can be 1, that is, the attribute information of the current point can be differentially predicted based on the reconstructed attribute information of the previous duplicate point of the current point.

The decoding method provided by the second embodiment of the present application is described in detail above in conjunction with Figure 11. The encoding method provided by the second embodiment of the present application is described in detail below in conjunction with Figure 12.

FIG12 is a schematic flow chart of the encoding method provided in the second embodiment of the present application. The method of FIG12 can be applied to an encoder. The encoding method can refer to a method for encoding attribute information (such as color information) of a point cloud. The following is a detailed example of each step of FIG12.

In step S1210, it is determined whether to perform a repeated point encoding operation.

In step S1220, the value of the first parameter is determined according to the determination result.

In step S1230, the value of the first parameter is encoded, and the obtained encoded bits are written into the bitstream.

The first parameter may be used to indicate whether to perform repeated point coding. Alternatively, the first parameter may be used to control repeated point coding. Alternatively, the first parameter may be used to indicate whether to perform repeated point coding when the point cloud to be coded has multiple attribute information.

The point cloud to be encoded may be all points in the point cloud, or may be part of the points in the point cloud. For example, the point cloud to be encoded may refer to points that are relatively concentrated in space.

The first parameter may be a high-level syntax element. In some embodiments, the first parameter may be called, for example, eligible_duplicate_pred.

In some embodiments, the first parameter may be a parameter in an Adaptation Parameter Set (APS).

The first parameter may include a first value and a second value. If the value of the first parameter is the first value, it is determined that repeated point coding is performed; if the value of the first parameter is the second value (different from the first value), it is determined that repeated point coding is not performed.

In some embodiments, if the repeated point contains only one kind of attribute information, the value of the first parameter may be set to the first value. If the repeated point contains multiple kinds of attribute information at the same time, the value of the first parameter may be set to the second value.

In some embodiments, the first value and the second value may be in parameter form. Alternatively, the first value and the second value may also be in digital form.

Exemplarily, the first value may be set to 1 and the second value may be set to 0; or, the first value may be set to 0 and the second value may be set to 1; or, the first value may be set to true and the second value may be set to false; or, the first value may be set to false and the second value may be set to true.

Assuming that the first value of the first parameter is 0 and the second value is 1, if the value of the first parameter is 0, it can be determined that the repeated point encoding operation is not performed; if the value of the first parameter is 1, it can be determined that the repeated point encoding operation is performed.

In some embodiments, the method of Figure 12 may also include: if the current point to be encoded is a repeated point, determining the encoding method of the sign bit of the residual of the second attribute component of the current point based on the residual of the first attribute component of the current point; wherein the first attribute component and the second attribute component belong to the same attribute information among multiple attribute information; or, the first attribute component and the second attribute component belong to different attribute information among multiple attribute information.

The current point may refer to a point to be encoded currently in the point cloud.

In the encoding order of the attribute components of the current point, the first attribute component is sorted before the second attribute component.

In some embodiments, in the encoding order, the first attribute component precedes the second attribute component.

Taking the first attribute component and the second attribute component as different color components of the current point as an example, the first attribute component can be the first color component in the color information, and the second attribute component can be the second color component in the color information. That is, at the encoding end, the first color component can be encoded to determine the residual of the first color component; then, the encoding method of the sign bit of the residual of the second color component can be determined based on the residual of the first color component (the value thereof).

For example, if the encoding end performs encoding in the order of RGB, the first attribute component may be an R component, and the second attribute component may be a G component.

For another example, if the encoding end performs encoding in the order of GRB, the first attribute component may be a G component, and the second attribute component may be an R component.

For another example, if the encoding end performs encoding in the order of YUV, the first attribute component may be a Y component, and the second attribute component may be a U component.

For another example, if the encoding end performs encoding in the order of UYV, the first attribute component may be a U component, and the second attribute component may be a Y component.

In some embodiments, the first attribute component includes all attribute components that precede the second attribute component in coding order.

Taking the first attribute component and the second attribute component as different color components of the current point as an example, the first attribute component may include the first color component and the second color component in the color information, and the second attribute component may be the third color component in the color information. That is, at the encoding end, the first color component and the second color component may be encoded to determine the residual of the first color component and the second color component; then, based on the residual of the first color component (the value thereof) and the residual of the second color component (the value thereof), the encoding method of the sign bit of the residual of the third color component may be determined.

For example, if the encoding end performs encoding in the order of RGB, the first attribute component may include an R component and a G component, and the second attribute component may be a B component.

For another example, if the encoding end performs encoding in the order of GRB, the first attribute component may include a G component and an R component, and the second attribute component may be a B component.

For another example, if the encoding end performs encoding in the order of YUV, the first attribute component may include a Y component and a U component, and the second attribute component may be a V component.

For another example, if the encoding end performs encoding in the order of UYV, the first attribute component may include a U component and a Y component, and the second attribute component may be a V component.

In some embodiments, one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information.

For example, if the encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the color information and then encode the attribute components corresponding to the reflectivity information, the first attribute component may be the attribute component corresponding to the color information, and the second attribute component may be the attribute component corresponding to the reflectivity information.

As an example, the encoding order of the attribute components of the current point is to encode RGB first and then encode the reflectivity information, so the first attribute component may include RGB, and the second attribute component may be the reflectivity information.

As another example, the encoding order of the attribute components of the current point is to encode YUV first and then encode reflectivity information. The quantity may include YUV, and the second attribute component may be reflectivity information.

For another example, if the encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the reflectivity information and then encode the attribute components corresponding to the color information, then the first attribute component may be the attribute component corresponding to the reflectivity information, and the second attribute component may be the attribute component corresponding to the color information.

As an example, the encoding order of the attribute components of the current point is to encode the reflectance information first and then encode RGB, so the first attribute component may be the reflectance information, and the second attribute component may include RGB.

As another example, the encoding order of the attribute components of the current point is to encode the reflectivity information first and then encode the YUV, so the first attribute component may be the reflectivity information, and the second attribute component may include the YUV.

In some embodiments, the above-mentioned method of determining the encoding method of the sign bit of the residual of the second attribute component of the current point based on the residual of the first attribute component of the current point may include: if the residual of the first attribute component of the current point is 0, determining not to encode the sign bit of the residual of the second attribute component.

Taking the encoding order of the current point as RGB as an example, the first attribute component can be the R component, and the second attribute component can be the G component. If the residual of the R component is 0, the sign bit of the residual of the G component may not be encoded (the residual of the R component is 0, which means that there are multiple repeated points with the same R component. At this time, the G components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the G component).

Taking the encoding order of the current point as RGB as an example, the first attribute component may include an R component and a G component, and the second attribute component may be a B component. If the residual of the R component and the residual of the G component are both 0, the sign bit of the residual of the B component may not be encoded (the residual of the R component and the residual of the G component are both 0, indicating that there are multiple repeated points with the same R component and G component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the B component).

Taking the encoding order of the current point as GRB as an example, the first attribute component can be the G component, and the second attribute component can be the R component. If the residual of the G component is 0, the sign bit of the residual of the R component may not be encoded (the residual of the G component is 0, which means that there are multiple repeated points with the same G component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the B component).

Taking the encoding order of the current point as GRB as an example, the first attribute component may include a G component and an R component, and the second attribute component may be a B component. If the residual of the G component and the residual of the R component are both 0, the sign bit of the residual of the B component may not be encoded (the residual of the G component and the residual of the R component are both 0, indicating that there are multiple repeated points with the same G component and R component. At this time, the B components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the B component).

Taking the encoding order of the current point as an example of first encoding RGB and then encoding the reflectivity information, the first attribute component may include R component, G component and B component, and the second attribute component may be the reflectivity information. If the residuals of the R component, G component and B component are all 0, the sign bit of the residual of the reflectivity information may not be encoded (the residuals of the R component, G component and B component are all 0, indicating that there are multiple repeated points with the same R component, G component and B component. At this time, the reflectivity information of the multiple repeated points is in ascending order, so there is no need to encode the sign bit of the residual of the reflectivity information).

Taking the encoding order of the current point as first encoding GRB and then encoding the reflectivity information as an example, the first attribute component may include G component, R component and B component, and the second attribute component may be the reflectivity information. If the residuals of the G component, R component and B component are all 0, the sign bit of the residual of the reflectivity information may not be encoded (the residuals of the G component, R component and B component are all 0, indicating that there are multiple repeated points with the same G component, R component and B component. At this time, the reflectivity information of the multiple repeated points is in ascending order, so there is no need to encode the sign bit of the residual of the reflectivity information).

Taking the encoding order of the current point as first encoding the reflectance information and then encoding RGB as an example, the first attribute component can be the reflectance information, and the second attribute component can be the R component. If the residual of the reflectance information is 0, the sign bit of the residual of the R component may not be encoded (the residual of the reflectance information is 0, indicating that there are multiple repeated points with the same reflectance information. At this time, the R components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the R component).

Taking the encoding order of the current point as first encoding the reflectivity information and then encoding GRB as an example, the first attribute component can be the reflectivity information, and the second attribute component can be the G component. If the residual of the reflectivity information is 0, the sign bit of the residual of the G component may not be encoded (the residual of the reflectivity information is 0, indicating that there are multiple repeated points with the same reflectivity information. At this time, the G components of the multiple repeated points are in ascending order, so there is no need to encode the sign bit of the residual of the G component).

In some embodiments, if the current point is not a duplicate point, the sign bits of the residuals of the various attribute components of the current point are encoded. If the current point is not a duplicate point, the sign bits of the various components of the color residual of the current point may be positive or negative. In this case, encoding the sign bits of the various components of the color residual of the current point can ensure the accuracy of the encoding.

In some embodiments, the method of FIG. 12 may further include: determining prediction information of the attribute information of the current point; and determining a color residual of the current point according to the prediction information of the attribute information of the current point.

The prediction information of the attribute information of the current point can be determined based on the reconstructed attribute information of the prediction reference point of the current point. The selection method of the prediction reference point of the current point can be determined based on the type of the current point. For example, if the current point is not a repeated point, it can be based on a certain distance (such as Manhattan distance) to determine the K neighboring points of the current point (K is a positive integer), and then use the K neighboring points as prediction reference points to perform weighted prediction on the attribute information of the current point. For another example, if the current point is a repeated point, the first M repeated points of the current point can be determined as prediction reference points, and then the predicted information of the attribute information of the current point is determined based on the reconstructed attribute information of the first M repeated points; where M is a positive integer. As an example, the value of M can be 1, that is, the attribute information of the current point can be differentially predicted based on the reconstructed attribute information of the previous repeated point of the current point.

In some embodiments, the method of Figure 12 may also include: determining the attribute residual of the current point based on the prediction information of the attribute information of the current point; quantizing the attribute residual of the current point to obtain the quantized residual of the current point; encoding the quantized residual and writing the obtained coded bits into the bit stream.

The method embodiment of the present application is described in detail above in conjunction with Figures 1 to 12, and the device embodiment of the present application is described in detail below in conjunction with Figures 13 to 19. It should be understood that the description of the method embodiment corresponds to the description of the device embodiment, so the part not described in detail can refer to the previous method embodiment.

Fig. 13 is a schematic diagram of the structure of an encoder provided by an embodiment of the present application. As shown in Fig. 13 , the encoder 1300 includes: a determination unit 1310 and a sorting unit 1320 .

The determination unit 1310 is configured to determine a set of repeated points of the point cloud to be encoded. The repeated points in the set of repeated points include multiple attribute information.

The sorting unit 1320 is configured to sort the repeated points in the repeated point set according to the multiple types of attribute information.

In some embodiments, the sorting unit 1320 is configured to: sort the repeated points in the repeated point set according to a first sorting method; wherein the first sorting method is to first sort according to the first attribute information among the multiple attribute information, and then sort according to the second attribute information among the multiple attribute information.

In some embodiments, the sorting unit 1320 is configured to: sort the duplicate points in the duplicate point set according to the first attribute information; if the duplicate point set includes at least two duplicate points with the same first attribute information, sort the at least two duplicate points according to the second attribute information of the at least two duplicate points.

In some embodiments, the first attribute information is color information, and the second attribute information is reflectivity information; or, the first attribute information is reflectivity information, and the second attribute information is color information.

In some embodiments, the first attribute information is the attribute information that is preferentially encoded among the multiple attribute information.

In some embodiments, the determination unit 1310 is further configured to: determine the value of a first parameter; if the value of the first parameter indicates to perform repeated point encoding, determine to perform the step of sorting the repeated points in the repeated point set according to the multiple attribute information.

In some embodiments, the determination unit 1310 is further configured to: if the value of the first parameter is a first value, determine to perform the repeated point encoding; if the value of the first parameter is a second value, determine not to perform the repeated point encoding.

In some embodiments, the encoder 1300 further includes an encoding unit configured to encode the value of the first parameter and write the obtained encoded bits into a bit stream.

In some embodiments, the first parameter is a parameter in an adaptive parameter set.

In some embodiments, the encoding unit is configured to determine the encoding method of the sign bit of the residual of the second attribute component of the current point based on the residual of the first attribute component of the current point if the current point to be encoded is a repeated point; wherein the first attribute component and the second attribute component belong to the same attribute information among the multiple attribute information; or, the first attribute component and the second attribute component belong to different attribute information among the multiple attribute information.

In some embodiments, the encoding unit is configured to determine not to encode a sign bit of the residual of the second attribute component if the residual of the first attribute component of the current point is 0.

In some embodiments, in the encoding order of the attribute components of the current point, the first attribute component is ranked higher than the second attribute component.

In some embodiments, in the encoding order, the first attribute component precedes the second attribute component; or, in the encoding order, the first attribute component includes all attribute components that precede the second attribute component.

In some embodiments, the first attribute component and the second attribute component are different color components of the current point.

In some embodiments, the encoding order of the color components of the current point is RGB, the first attribute component is the R component, and the second attribute component is the G component; or, the encoding order of the color components of the current point is RGB, the first attribute component includes the R component and the G component, and the second attribute component is the B component; or, the encoding order of the color components of the current point is GRB, the first attribute component is the G component, and the second attribute component is the R component; or, the encoding order of the color components of the current point is GRB, the first attribute component includes the G component and the R component, and the second attribute component is the B component; or, the encoding order of the color components of the current point is YUV, the first attribute component is the Y component, and the second attribute component is the U component; or, the encoding order of the color components of the current point is YUV, the first attribute component includes the Y component and the U component, and the second attribute component is the V component; or, the encoding order of the color components of the current point is UYV, the first attribute component is the U component, and the second attribute component is Y component; or, the encoding order of the color component of the current point is UYV, the first attribute component includes a U component and a Y component, and the second attribute component is a V component.

In some embodiments, one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information.

In some embodiments, the encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the color information and then encode the attribute components corresponding to the reflectivity information, the first attribute component is the attribute component corresponding to the color information, and the second attribute component is the attribute component corresponding to the reflectivity information; or, the encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the reflectivity information and then encode the attribute components corresponding to the color information, the first attribute component is the attribute component corresponding to the reflectivity information, and the second attribute component is the attribute component corresponding to the color information.

In some embodiments, the encoding unit is configured to encode a sign bit of a residual of each attribute component of the current point if the current point is not a repeated point.

In some embodiments, the encoding unit is configured to determine prediction information of the color information of the current point; and determine the color residual of the current point according to the prediction information of the color information of the current point.

In some embodiments, the encoding unit is configured to determine the prediction information based on reconstructed color information of M repeated points preceding the current point if the current point is a repeated point; wherein M is a positive integer.

In some embodiments, the encoding unit is configured to quantize the color residual of the current point to determine the quantized residual of the current point; encode the quantized residual, and write the obtained encoded bits into a bitstream.

It is understandable that in the embodiments of the present application, a "unit" may be a part of a circuit, a part of a processor, a part of a program or software, etc., and of course, it may be a module, or it may be non-modular. Moreover, the components in the present embodiment may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional module.

If the integrated unit is implemented in the form of a software function module and is not sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this embodiment is essentially or the part that contributes to the prior art or the whole or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) or a processor to perform all or part of the steps of the method described in this embodiment. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., which can store program code.

Therefore, an embodiment of the present application provides a computer-readable storage medium, which is applied to the encoder 1300. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the decoding method described in any one of the aforementioned embodiments.

Based on the composition of the above-mentioned encoder 1300 and the computer-readable storage medium, refer to Figure 14, which shows a specific hardware structure diagram of the encoder 1300 provided in an embodiment of the present application. As shown in Figure 14, the encoder 1400 may include: a communication interface 1410, a memory 1420 and a processor 1430; each component is coupled together through a bus system 1440. It can be understood that the bus system 1440 is used to realize the connection and communication between these components. In addition to the data bus, the bus system 1440 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, various buses are marked as bus system 1440 in Figure 14. Among them,

The communication interface 1410 is used to receive and send signals during the process of sending and receiving information with other external network elements;

Memory 1420, used for storing computer programs;

The processor 1430 is configured to, when running the computer program, execute:

Determine a set of repeated points of a point cloud to be encoded; wherein the repeated points in the set of repeated points include multiple attribute information;

The repeated points in the repeated point set are sorted according to the multiple types of attribute information.

It can be understood that the memory 1420 in the embodiment of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate synchronous DRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM bus RAM (DRRAM). The memory 1420 of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

The processor 1430 may be an integrated circuit chip with signal processing capability. The steps can be completed by the hardware integrated logic circuit or software instructions in the processor 1430. The above-mentioned processor 1430 can be a general-purpose processor, a digital signal processor (Digital Signal Processor, DSP), an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), a field programmable gate array (Field Programmable Gate Array, FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The various methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor to be executed, or the hardware and software modules in the decoding processor are combined and executed. 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 or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 1420, and the processor 1430 reads the information in the memory 1420 and completes the steps of the above method in combination with its hardware.

It is understood that the embodiments described in this application can be implemented in hardware, software, firmware, middleware, microcode or a combination thereof. For hardware implementation, the processing unit can be implemented in one or more application specific integrated circuits (Application Specific Integrated Circuits, ASIC), digital signal processors (Digital Signal Processing, DSP), digital signal processing devices (DSP Device, DSPD), programmable logic devices (Programmable Logic Device, PLD), field programmable gate arrays (Field-Programmable Gate Array, FPGA), general processors, controllers, microcontrollers, microprocessors, other electronic units for performing the functions described in this application or a combination thereof. For software implementation, the technology described in this application can be implemented by a module (such as a process, function, etc.) that performs the functions described in this application. The software code can be stored in a memory and executed by a processor. The memory can be implemented in the processor or outside the processor.

Optionally, as another embodiment, the processor 1430 is further configured to execute the encoding method in the aforementioned first embodiment when running the computer program.

FIG15 is a schematic diagram of the structure of a decoder provided by another embodiment of the present application. The decoder 1500 of FIG15 includes a first decoding unit 1510 and a second decoding unit 1520 .

The first decoding unit 1510 is configured to parse the code stream and determine a value of the first parameter.

The second decoding unit 1520 is configured to perform a repeated point decoding operation if the value of the first parameter is a first value; wherein the value of the first parameter includes a first value and a second value, the first value is used to indicate that the repeated point decoding operation is performed, and the second value is used to indicate that the repeated point decoding operation is not performed.

In some embodiments, the first parameter is a parameter in an adaptive parameter set.

In some embodiments, the decoder 1500 further includes a third decoding unit configured to determine a decoding method for a sign bit of a residual of a second attribute component of the current point based on a residual of a first attribute component of the current point if the current point to be decoded is a repeated point.

In some embodiments, the third decoding unit is configured to determine not to decode the sign bit of the residual of the second attribute component if the residual of the first attribute component of the current point is 0.

In some embodiments, in the decoding order of the attribute components of the current point, the first attribute component is ranked higher than the second attribute component.

In some embodiments, in the decoding order, the first attribute component precedes the second attribute component; or, in the decoding order, the first attribute component includes all attribute components preceding the second attribute component.

In some embodiments, the first attribute component and the second attribute component are different color components of the current point.

In some embodiments, the decoding order of the color components of the current point is RGB, the first attribute component is the R component, and the second attribute component is the G component; or, the decoding order of the color components of the current point is RGB, the first attribute component includes the R component and the G component, and the second attribute component is the B component; or, the decoding order of the color components of the current point is GRB, the first attribute component is the G component, and the second attribute component is the R component; or, the decoding order of the color components of the current point is GRB, the first attribute component includes the G component and the R component, and the second attribute component is the B component; or, the decoding order of the color components of the current point is YUV, the first attribute component is the Y component, and the second attribute component is the U component; or, the decoding order of the color components of the current point is YUV, the first attribute component includes the Y component and the U component, and the second attribute component is the V component; or, the decoding order of the color components of the current point is UYV, the first attribute component is the U component, and the second attribute component is the Y component; or, the decoding order of the color components of the current point is UYV, the first attribute component includes the U component and the Y component, and the second attribute component is the V component.

In some embodiments, one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information.

In some embodiments, the decoding order of the attribute components of the current point is to first decode the attribute components corresponding to the color information and then decode the attribute components corresponding to the reflectivity information, the first attribute component is the attribute component corresponding to the color information, and the second attribute component is the attribute component corresponding to the reflectivity information; or, the decoding order of the attribute components of the current point is to first decode the attribute components corresponding to the reflectivity information and then decode the attribute components corresponding to the color information, the first attribute component is the attribute component corresponding to the reflectivity information, and the second attribute component is the attribute component corresponding to the color information.

In some embodiments, the decoder 1500 also includes a fourth decoding unit, which is configured to determine the first M repeated points of the current point if the current point to be decoded is a repeated point; wherein M is a positive integer; and use the first M repeated points as prediction reference points to perform attribute prediction on the current point.

In some embodiments, the decoder 1500 further includes a fifth decoding unit configured to determine the reconstructed attribute information of the current point based on the prediction information and the attribute residual of the attribute information of the current point.

It is understandable that in the embodiments of the present application, a "unit" may be a part of a circuit, a part of a processor, a part of a program or software, etc., and of course, it may be a module, or it may be non-modular. Moreover, the components in the present embodiment may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional module.

If the integrated unit is implemented in the form of a software function module and is not sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this embodiment is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) or a processor to perform all or part of the steps of the method described in this embodiment. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

Therefore, an embodiment of the present application provides a computer-readable storage medium, which is applied to the decoder 1500. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the decoding method in the first embodiment is implemented.

Based on the composition of the above-mentioned decoder 1500 and the computer-readable storage medium, refer to Figure 16, which shows a specific hardware structure diagram of the decoder 1500 provided in an embodiment of the present application. As shown in Figure 16, the decoder 1600 may include: a communication interface 1610, a memory 1620 and a processor 1630; each component is coupled together through a bus system 1640. It can be understood that the bus system 1640 is used to realize the connection and communication between these components. In addition to the data bus, the bus system 1640 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, various buses are marked as bus system 1640 in Figure 16. Among them,

The communication interface 1610 is used to receive and send signals during the process of sending and receiving information with other external network elements;

Memory 1620, used for storing computer programs;

The processor 1630 is configured to, when running the computer program, execute:

Parse the code stream to determine the value of the first parameter;

If the value of the first parameter is the first value, a repeated point decoding operation is performed; wherein the value of the first parameter includes a first value and a second value, the first value is used to indicate that the repeated point decoding operation is performed, and the second value is used to indicate that the repeated point decoding operation is not performed.

It can be understood that the memory 1620 in the embodiment of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate synchronous DRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM bus RAM (DRRAM). The memory 1620 of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

The processor 1630 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the hardware integrated logic circuit in the processor 1630 or the instruction in the form of software. The above processor 1630 may be a general processor, a digital signal processor (Digital Signal Processor, DSP), an application specific integrated circuit (Application Specific Integrated Circuit, ASIC), a field programmable gate array (Field Programmable Gate Array, FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as a hardware decoding processor to execute, or the hardware and software modules in the decoding processor can be executed. 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 or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 1620, and the processor 1630 reads the information in the memory 1620 and completes the steps of the above method in combination with its hardware.

It will be understood that the embodiments described herein may be implemented by hardware, software, firmware, middleware, microcode, or a combination thereof. For hardware implementation, the processing unit can be implemented in one or more application specific integrated circuits (Application Specific Integrated Circuits, ASIC), digital signal processors (Digital Signal Processing, DSP), digital signal processing devices (DSP Device, DSPD), programmable logic devices (Programmable Logic Device, PLD), field programmable gate arrays (Field-Programmable Gate Array, FPGA), general-purpose processors, controllers, microcontrollers, microprocessors, other electronic units for performing the functions described in the present application, or combinations thereof. For software implementation, the technology described in the present application can be implemented by modules (such as processes, functions, etc.) that perform the functions described in the present application. The software code can be stored in a memory and executed by a processor. The memory can be implemented in the processor or outside the processor.

Optionally, as another embodiment, the processor 1630 is further configured to execute the decoding method described in the aforementioned second embodiment when running the computer program.

Fig. 17 is a schematic diagram of the structure of an encoder provided by another embodiment of the present application. As shown in Fig. 17 , the encoder 1700 includes: a determination unit 1710 and an encoding unit 1720 .

The determination unit 1710 is configured to determine whether to perform a repeated point encoding operation, and determine a value of the first parameter according to the determination result.

The encoding unit 1720 is configured to encode the value of the first parameter and write the obtained coded bits into the bitstream;

The value of the first parameter includes a first value and a second value, the first value is used to indicate to perform the repeated point encoding operation, and the second value is used to indicate not to perform the repeated point encoding operation.

In some embodiments, the first parameter is a parameter in an adaptive parameter set.

In some embodiments, the encoding unit 1720 is further configured to: if the current point to be encoded is a repeated point, determine the encoding method of the sign bit of the residual of the second attribute component of the current point according to the residual of the first attribute component of the current point.

In some embodiments, the encoding unit 1720 is configured to: if the residual of the first attribute component of the current point is 0, determine not to encode the sign bit of the residual of the second attribute component.

In some embodiments, in the encoding order of the attribute components of the current point, the first attribute component is ranked higher than the second attribute component.

In some embodiments, in the encoding order, the first attribute component precedes the second attribute component; or, in the encoding order, the first attribute component includes all attribute components that precede the second attribute component.

In some embodiments, the first attribute component and the second attribute component are different color components of the current point.

In some embodiments, the encoding order of the color components of the current point is RGB, the first attribute component is the R component, and the second attribute component is the G component; or, the encoding order of the color components of the current point is RGB, the first attribute component includes the R component and the G component, and the second attribute component is the B component; or, the encoding order of the color components of the current point is GRB, the first attribute component is the G component, and the second attribute component is the R component; or, the encoding order of the color components of the current point is GRB, the first attribute component includes the G component and the R component, and the second attribute component is the B component; or, the encoding order of the color components of the current point is YUV, the first attribute component is the Y component, and the second attribute component is the U component; or, the encoding order of the color components of the current point is YUV, the first attribute component includes the Y component and the U component, and the second attribute component is the V component; or, the encoding order of the color components of the current point is UYV, the first attribute component is the U component, and the second attribute component is the Y component; or, the encoding order of the color components of the current point is UYV, the first attribute component includes the U component and the Y component, and the second attribute component is the V component.

In some embodiments, one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information.

In some embodiments, the encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the color information and then encode the attribute components corresponding to the reflectivity information, the first attribute component is the attribute component corresponding to the color information, and the second attribute component is the attribute component corresponding to the reflectivity information; or, the encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the reflectivity information and then encode the attribute components corresponding to the color information, the first attribute component is the attribute component corresponding to the reflectivity information, and the second attribute component is the attribute component corresponding to the color information.

In some embodiments, the determination unit 1710 is configured as follows: if the current point to be encoded is a repeated point, then according to the repeated point order, the first M repeated points of the current point are determined; wherein M is a positive integer; and the first M repeated points are used as prediction reference points to perform attribute prediction on the current point.

In some embodiments, the encoding unit 1720 is further configured to: determine the attribute residual of the current point based on the prediction information of the attribute information of the current point; quantize the attribute residual of the current point to obtain the quantized residual of the current point; encode the quantized residual and write the obtained encoded bits into the bit stream.

It is understandable that in the embodiments of the present application, a "unit" may be a part of a circuit, a part of a processor, a part of a program or software, etc., and of course, it may be a module, or it may be non-modular. Moreover, the components in the present embodiment may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional module.

If the integrated unit is implemented in the form of a software function module and is not sold or used as an independent product, it can be stored in Based on this understanding, the technical solution of this embodiment, or the part that contributes to the prior art, or the whole or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server, or network device, etc.) or a processor to perform all or part of the steps of the method described in this embodiment. The aforementioned storage medium includes: U disk, mobile hard disk, read only memory (ROM), random access memory (RAM), disk or optical disk, etc., which can store program code.

Therefore, an embodiment of the present application provides a computer-readable storage medium, which is applied to the encoder 1700. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the decoding method described in any one of the aforementioned embodiments.

Based on the composition of the above-mentioned encoder 1700 and the computer-readable storage medium, refer to Figure 18, which shows a specific hardware structure diagram of the encoder 1700 provided in an embodiment of the present application. As shown in Figure 18, the encoder 1800 may include: a communication interface 1810, a memory 1820 and a processor 1830; each component is coupled together through a bus system 1840. It can be understood that the bus system 1840 is used to realize the connection and communication between these components. In addition to the data bus, the bus system 1840 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, various buses are marked as bus system 1840 in Figure 18. Among them,

Communication interface 1810, used for receiving and sending signals during the process of sending and receiving information with other external network elements;

A memory 1820, used for storing computer programs;

The processor 1830 is configured to, when running the computer program, execute:

Determine whether to perform repeated point encoding operation;

Determining a value of the first parameter according to the determination result;

Encoding the value of the first parameter, and writing the obtained coded bits into a bit stream;

The value of the first parameter includes a first value and a second value, the first value is used to indicate to perform the repeated point encoding operation, and the second value is used to indicate not to perform the repeated point encoding operation.

It can be understood that the memory 1820 in the embodiment of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate synchronous DRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM bus RAM (DRRAM). The memory 1820 of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

The processor 1830 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the hardware integrated logic circuit in the processor 1830 or the instruction in the form of software. The above processor 1830 can be a general processor, a digital signal processor (Digital Signal Processor, DSP), an application specific integrated circuit (Application Specific Integrated Circuit, ASIC), a field programmable gate array (Field Programmable Gate Array, FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as a hardware decoding processor to execute, or the hardware and software modules in the decoding processor can be executed. 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 or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 1820, and the processor 1830 reads the information in the memory 1820 and completes the steps of the above method in combination with its hardware.

It is understood that the embodiments described in this application can be implemented in hardware, software, firmware, middleware, microcode or a combination thereof. For hardware implementation, the processing unit can be implemented in one or more application specific integrated circuits (Application Specific Integrated Circuits, ASIC), digital signal processors (Digital Signal Processing, DSP), digital signal processing devices (DSP Device, DSPD), programmable logic devices (Programmable Logic Device, PLD), field programmable gate arrays (Field-Programmable Gate Array, FPGA), general processors, controllers, microcontrollers, microprocessors, other electronic units for performing the functions described in this application or a combination thereof. For software implementation, the technology described in this application can be implemented by a module (such as a process, function, etc.) that performs the functions described in this application. The software code can be stored in a memory and executed by a processor. The memory can be implemented in the processor or outside the processor.

Optionally, as another embodiment, the processor 1830 is further configured to execute the encoding method described in the aforementioned second embodiment when running the computer program.

FIG19 is a schematic diagram of the structure of a coding and decoding system provided in an embodiment of the present application. As shown in FIG19 , a coding and decoding system 1900 may include Encoder 1910 and decoder 1920 .

In the embodiment of the present application, the encoder 1910 may be the encoder described in any one of the aforementioned embodiments, and the decoder 1920 may be the decoder described in any one of the aforementioned embodiments.

It should be noted that, in this application, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

The methods disclosed in several method embodiments provided in this application can be arbitrarily combined without conflict to obtain new method embodiments.

The features disclosed in several product embodiments provided in this application can be arbitrarily combined without conflict to obtain new product embodiments.

The features disclosed in several method or device embodiments provided in this application can be arbitrarily combined without conflict to obtain new method embodiments or device embodiments.

The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims (52)

A coding method, applied to an encoder, comprising: Determine a set of repeated points of a point cloud to be encoded; wherein the repeated points in the set of repeated points include multiple attribute information; The repeated points in the repeated point set are sorted according to the multiple types of attribute information. The method according to claim 1, wherein the step of sorting the repeated points in the set of repeated points according to the multiple attribute information comprises: Sorting the repeated points in the repeated point set according to a first sorting method; The first sorting method is to first sort according to the first attribute information among the multiple attribute information, and then sort according to the second attribute information among the multiple attribute information. The method according to claim 2, wherein the step of sorting the repeated points in the set of repeated points in a first sorting manner comprises: sorting the repeated points in the repeated point set according to the first attribute information; If the set of repeated points includes at least two repeated points having the same first attribute information, the at least two repeated points are sorted according to the second attribute information of the at least two repeated points. The method according to claim 2 or 3, wherein: The first attribute information is color information, and the second attribute information is reflectivity information; or, The first attribute information is reflectance information, and the second attribute information is color information. The method according to any one of claims 1 to 4, wherein the first attribute information is attribute information that is preferentially encoded among the multiple attribute information. The method according to any one of claims 1 to 5, wherein the method further comprises: Determine the value of the first parameter; If the value of the first parameter indicates that repeated point encoding is to be performed, it is determined to perform the step of sorting the repeated points in the repeated point set according to the multiple attribute information. The method according to claim 6, wherein the method further comprises: If the value of the first parameter is the first value, determining to execute the repeated point encoding; If the value of the first parameter is the second value, it is determined not to perform the repeated point encoding. The method according to claim 6 or 7, wherein the method further comprises: The value of the first parameter is encoded, and the obtained encoded bits are written into a bit stream. The method according to any one of claims 6 to 8, wherein the first parameter is a parameter in an adaptive parameter set. The method according to any one of claims 1 to 9, further comprising: If the current point to be encoded is a repeated point, determining the encoding method of the sign bit of the residual of the second attribute component of the current point according to the residual of the first attribute component of the current point; The first attribute component and the second attribute component belong to the same attribute information among the multiple attribute information; or the first attribute component and the second attribute component belong to different attribute information among the multiple attribute information. The method according to claim 10, wherein the determining, based on the residual of the first attribute component of the current point, the encoding method of the sign bit of the residual of the second attribute component of the current point comprises: If the residual of the first attribute component of the current point is 0, it is determined not to encode the sign bit of the residual of the second attribute component. The method according to claim 11 is characterized in that, in the encoding order of the attribute components of the current point, the first attribute component is ranked higher than the second attribute component. The method according to claim 12, wherein: In the coding order, the first attribute component is arranged before the second attribute component; or, In the coding order, the first attribute component includes all attribute components that precede the second attribute component. The method according to any one of claims 10 to 13, wherein the first attribute component and the second attribute component are different color components of the current point. The method according to claim 14, wherein: The encoding order of the color component of the current point is RGB, the first attribute component is the R component, and the second attribute component is the G component; or, The encoding order of the color component of the current point is RGB, the first attribute component includes an R component and a G component, and the second attribute component is a B component; or The encoding order of the color component of the current point is GRB, the first attribute component is G component, and the second attribute component is R Quantity; or The coding order of the color component of the current point is GRB, the first attribute component includes a G component and an R component, and the second attribute component is a B component; or, The encoding order of the color component of the current point is YUV, the first attribute component is the Y component, and the second attribute component is the U component; or The encoding order of the color component of the current point is YUV, the first attribute component includes a Y component and a U component, and the second attribute component is a V component; or The encoding order of the color component of the current point is UYV, the first attribute component is the U component, and the second attribute component is the Y component; or, The encoding order of the color component of the current point is UYV, the first attribute component includes a U component and a Y component, and the second attribute component is a V component. The method according to any one of claims 10 to 13, wherein one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information. The method according to claim 16, wherein: The encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the color information and then encode the attribute components corresponding to the reflectivity information, the first attribute components are the attribute components corresponding to the color information, and the second attribute components are the attribute components corresponding to the reflectivity information; or The encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the reflectivity information and then encode the attribute components corresponding to the color information. The first attribute component is the attribute component corresponding to the reflectivity information, and the second attribute component is the attribute component corresponding to the color information. The method according to any one of claims 10 to 17, wherein the method further comprises: If the current point is not a repeated point, the sign bit of the residual of each attribute component of the current point is encoded. The method according to any one of claims 10 to 18, wherein the method further comprises: Determine prediction information of the color information of the current point; Determine the color residual of the current point according to the prediction information of the color information of the current point. The method according to claim 19, wherein the determining the prediction information of the color information of the current point comprises: If the current point is a repeated point, the prediction information is determined according to the reconstructed color information of the M repeated points preceding the current point, wherein M is a positive integer. The method according to any one of claims 1 to 20, wherein the method further comprises: quantizing the color residual of the current point to determine the quantized residual of the current point; The quantized residual is encoded, and the obtained encoded bits are written into a bit stream. A decoding method, applied to a decoder, comprising: Parse the code stream to determine the value of the first parameter; If the value of the first parameter is the first value, performing a repeated point decoding operation; The value of the first parameter includes a first value and a second value, the first value is used to indicate to perform the repeated point decoding operation, and the second value is used to indicate not to perform the repeated point decoding operation. The method according to claim 22, wherein the first parameter is a parameter in an adaptive parameter set. The method according to claim 22 or 23, further comprising: If the current point to be decoded is a repeated point, a decoding method for the sign bit of the residual of the second attribute component of the current point is determined according to the residual of the first attribute component of the current point. The method according to claim 24, wherein the determining, based on the residual of the first attribute component of the current point, a decoding method of the sign bit of the residual of the second attribute component of the current point comprises: If the residual of the first attribute component of the current point is 0, it is determined not to decode the sign bit of the residual of the second attribute component. The method according to claim 25 is characterized in that, in the decoding order of the attribute components of the current point, the first attribute component is ranked higher than the second attribute component. The method according to claim 26, wherein: In the decoding order, the first attribute component is arranged before the second attribute component; or, In the decoding order, the first attribute component includes all attribute components that precede the second attribute component. The method according to any one of claims 24 to 27, wherein the first attribute component and the second attribute component are different color components of the current point. The method according to claim 28, wherein: The decoding order of the color components of the current point is RGB, the first attribute component is the R component, and the second attribute component is the G component; or, The decoding order of the color components of the current point is RGB, the first attribute component includes an R component and a G component, and the second attribute component is a B component; or, The decoding order of the color components of the current point is GRB, the first attribute component is the G component, and the second attribute component is the R component; or, The decoding order of the color components of the current point is GRB, the first attribute component includes a G component and an R component, and the second attribute component is a B component; or, The decoding order of the color component of the current point is YUV, the first attribute component is the Y component, and the second attribute component is the U component; or, The decoding order of the color component of the current point is YUV, the first attribute component includes a Y component and a U component, and the second attribute component is a V component; or, The decoding order of the color components of the current point is UYV, the first attribute component is the U component, and the second attribute component is the Y component; or, The decoding order of the color components of the current point is UYV, the first attribute component includes a U component and a Y component, and the second attribute component is a V component. The method according to any one of claims 24 to 27, wherein one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information. The method according to claim 30, wherein: The decoding order of the attribute components of the current point is to first decode the attribute components corresponding to the color information and then decode the attribute components corresponding to the reflectivity information, the first attribute components are the attribute components corresponding to the color information, and the second attribute components are the attribute components corresponding to the reflectivity information; or The decoding order of the attribute components of the current point is to first decode the attribute components corresponding to the reflectivity information and then decode the attribute components corresponding to the color information. The first attribute component is the attribute component corresponding to the reflectivity information, and the second attribute component is the attribute component corresponding to the color information. The method according to any one of claims 22 to 31, wherein the method further comprises: If the current point to be decoded is a repeated point, determine the first M repeated points of the current point; where M is a positive integer; The first M repeated points are used as prediction reference points to perform attribute prediction on the current point. The method according to claim 32, wherein the method further comprises: The reconstructed attribute information of the current point is determined according to the prediction information and the attribute residual of the attribute information of the current point. A coding method, applied to an encoder, comprising: Determine whether to perform repeated point encoding operation; Determining a value of the first parameter according to the determination result; Encoding the value of the first parameter, and writing the obtained coded bits into a bit stream; The value of the first parameter includes a first value and a second value, the first value is used to indicate to perform the repeated point encoding operation, and the second value is used to indicate not to perform the repeated point encoding operation. The method according to claim 34, wherein the first parameter is a parameter in an adaptive parameter set. The method according to any one of claims 34 or 35, further comprising: If the current point to be encoded is a repeated point, the encoding method of the sign bit of the residual of the second attribute component of the current point is determined according to the residual of the first attribute component of the current point. The method according to claim 36, wherein the determining, based on the residual of the first attribute component of the current point, the encoding method of the sign bit of the residual of the second attribute component of the current point comprises: If the residual of the first attribute component of the current point is 0, it is determined not to encode the sign bit of the residual of the second attribute component. The method according to claim 37 is characterized in that, in the encoding order of the attribute components of the current point, the first attribute component is ranked higher than the second attribute component. The method according to claim 38, wherein: In the coding order, the first attribute component is arranged before the second attribute component; or, In the coding order, the first attribute component includes all attribute components that precede the second attribute component. The method according to any one of claims 36 to 39, wherein the first attribute component and the second attribute component are different color components of the current point. The method of claim 40, wherein: The encoding order of the color component of the current point is RGB, the first attribute component is the R component, and the second attribute component is the G component; or, The encoding order of the color component of the current point is RGB, the first attribute component includes an R component and a G component, and the second attribute component is a B component; or The coding order of the color component of the current point is GRB, the first attribute component is the G component, and the second attribute component is the R component; or, The coding order of the color component of the current point is GRB, the first attribute component includes a G component and an R component, and the second attribute component is a B component; or, The encoding order of the color component of the current point is YUV, the first attribute component is the Y component, and the second attribute component is the U component; or The encoding order of the color component of the current point is YUV, the first attribute component includes a Y component and a U component, and the second attribute component is a V component; or The encoding order of the color component of the current point is UYV, the first attribute component is the U component, and the second attribute component is the Y component; or, The encoding order of the color component of the current point is UYV, the first attribute component includes a U component and a Y component, and the second attribute component is a V component. The method according to any one of claims 36 to 39, wherein one of the first attribute component and the second attribute component is an attribute component corresponding to color information, and the other is an attribute component corresponding to reflectivity information. The method of claim 42, wherein: The encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the color information and then encode the attribute components corresponding to the reflectivity information, the first attribute components are the attribute components corresponding to the color information, and the second attribute components are the attribute components corresponding to the reflectivity information; or The encoding order of the attribute components of the current point is to first encode the attribute components corresponding to the reflectivity information and then encode the attribute components corresponding to the color information. The first attribute component is the attribute component corresponding to the reflectivity information, and the second attribute component is the attribute component corresponding to the color information. The method according to any one of claims 34 to 43, wherein the method further comprises: If the current point to be encoded is a repeated point, the first M repeated points of the current point are determined according to the repeated point sequence; wherein M is a positive integer; The first M repeated points are used as prediction reference points to perform attribute prediction on the current point. The method according to claim 44, wherein the method further comprises: Determining an attribute residual of the current point according to the prediction information of the attribute information of the current point; quantizing the attribute residual of the current point to obtain the quantized residual of the current point; The quantized residual is encoded, and the obtained encoded bits are written into a bit stream. An encoder, comprising: A determination unit, configured to determine a set of repeated points of a point cloud to be encoded; wherein the repeated points in the set of repeated points include a variety of attribute information; The sorting unit is configured to sort the repeated points in the repeated point set according to the multiple attribute information. An encoder, comprising: Memory for storing computer programs; A processor, configured to execute the method according to any one of claims 1 to 21 when running the computer program. A decoder, comprising: A first decoding unit is configured to parse the code stream and determine a value of the first parameter; The second decoding unit is configured to perform a repeated point decoding operation if the value of the first parameter is a first value; wherein the value of the first parameter includes a first value and a second value, the first value is used to indicate that the repeated point decoding operation is performed, and the second value is used to indicate that the repeated point decoding operation is not performed. A decoder, comprising: Memory for storing computer programs; A processor, configured to execute the method according to any one of claims 22 to 33 when running the computer program. An encoder, comprising: a determination unit, configured to determine whether to perform a repeated point encoding operation, and determine a value of the first parameter according to the determination result; an encoding unit, configured to encode the value of the first parameter and write the obtained encoded bits into a bit stream; The value of the first parameter includes a first value and a second value, the first value is used to indicate to perform the repeated point encoding operation, The second value is used to indicate not to perform the repeated point encoding operation. An encoder, comprising: Memory for storing computer programs; A processor for executing the method according to any one of claims 34 to 45 when running the computer program. A computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed, it implements the method according to any one of claims 1 to 21, the method according to any one of claims 22 to 33, or the method according to any one of claims 34 to 45.