WO2024120324A1 - Attribute transformation decoding method, attribute transformation coding method, and terminal - Google Patents

Abstract

The present application belongs to the technical field of coding and decoding. Disclosed are an attribute transformation coding method, an attribute transformation decoding method, and a terminal. The attribute transformation decoding method provided in the embodiments of the present application comprises: acquiring a target code stream and a target shift number that is associated with the target code stream; performing decoding and inverse quantization on the target code stream, so as to obtain a reconstruction transformation coefficient corresponding to a point cloud to be decoded; according to the target shift number, executing a first shift operation on the reconstruction transformation coefficient corresponding to said point cloud; according to a geometric distance between points to be decoded that have been reordered, constructing a transformation tree structure corresponding to said point cloud, and on the basis of the transformation tree structure, performing inverse transformation processing on the reconstruction transformation coefficient on which the first shift operation has been executed, so as to obtain a reconstruction attribute value corresponding to said point cloud; and according to the target shift number, executing a second shift operation on the reconstruction attribute value corresponding to said point cloud, so as to obtain reconstruction attribute information corresponding to said point cloud.

Description

Attribute transformation decoding method, attribute transformation encoding method and terminal

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 202211584648.9 filed in China on December 9, 2022, the entire contents of which are incorporated herein by reference.

Technical Field

The present application belongs to the field of coding and decoding technology, and specifically relates to an attribute transformation decoding method, an attribute transformation encoding method and a terminal.

Background technique

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.

The encoding process of point cloud involves attribute transformation coding. In the attribute transformation coding process, the point cloud is reordered based on its geometric information and a multi-layer transformation tree structure is constructed. Then, the attribute coefficients corresponding to each node in the transformation tree structure are transformed through the transformation matrix to realize the attribute transformation coding of the point cloud.

However, in the above process of constructing a multi-layer transform tree structure, the encoder needs to perform a shift operation on the attribute information of the point cloud to construct the transform tree structure. During the decoding process, the decoder also needs to perform a shift operation on the reconstructed attribute information of the point cloud. However, if the number of shifts performed by the decoder is greater than the number of shifts performed by the encoder, the value calculated by the decoder may exceed the specified bit width upper limit, thereby causing a decoding error.

Summary of the invention

The embodiments of the present application provide an attribute transformation decoding method, an attribute transformation encoding method and a terminal, which can solve the problem in the related art that the value calculated by the decoding end exceeds the specified bit width upper limit, thereby causing decoding errors.

In a first aspect, an attribute transformation decoding method is provided, comprising:

The decoding end obtains a target bitstream and a target shift number associated with the target bitstream, where the target shift number associated with the target bitstream is the shift number used by the encoding end to perform a shift operation;

The decoding end decodes and dequantizes the target bitstream to obtain reconstruction transformation coefficients corresponding to the point cloud to be decoded;

The decoding end performs a first shift operation on the reconstructed transformation coefficients corresponding to the to-be-decoded point cloud according to the target shift number;

The decoding end constructs a transformation tree structure corresponding to the point cloud to be decoded according to the geometric distances between the reordered points to be decoded, and performs inverse transformation processing on the reconstructed transformation coefficients after the first shift operation based on the transformation tree structure to obtain a reconstructed attribute value corresponding to the point cloud to be decoded; the reordered points to be decoded are determined based on the reconstructed geometric information of the point cloud to be decoded obtained by decoding the target bitstream;

The decoding end performs a second shift on the reconstructed attribute value corresponding to the to-be-decoded point cloud according to the target shift number. operation to obtain the reconstructed attribute information corresponding to the point cloud to be decoded; the shifting direction of the second shifting operation is opposite to the shifting direction of the first shifting operation.

In a second aspect, an attribute transformation encoding method is provided, comprising:

The encoding end reorders the point cloud to be encoded based on the acquired geometric information of the point cloud to be encoded;

The encoding end performs a first shift operation on the attribute information of the reordered point cloud to be encoded according to a target shift number associated with the point cloud to be encoded;

The encoder constructs a transformation tree structure corresponding to the point cloud to be encoded according to the geometric distances between the reordered points to be encoded, and transforms the attribute information after the first shift operation based on the transformation tree structure to obtain transformation coefficients corresponding to the point cloud to be encoded;

The encoder performs a second shift operation on the transform coefficients corresponding to the to-be-encoded point cloud according to the target shift number, where a shift direction of the second shift operation is opposite to a shift direction of the first shift operation;

The encoding end quantizes and encodes the transformation coefficients after the second shift operation is performed to generate a target code stream.

In a third aspect, an attribute transformation decoding device is provided, comprising:

An acquisition module, used to acquire a target bitstream and a target shift number associated with the target bitstream, where the target shift number associated with the target bitstream is the shift number used by the encoder to perform a shift operation;

A first processing module is used to decode and dequantize the target bitstream to obtain reconstruction transformation coefficients corresponding to the point cloud to be decoded;

A first shift module, configured to perform a first shift operation on the reconstructed transformation coefficients corresponding to the to-be-decoded point cloud according to the target shift number;

A second processing module is used to construct a transformation tree structure corresponding to the point cloud to be decoded according to the geometric distances between the reordered points to be decoded, and to perform inverse transformation processing on the reconstructed transformation coefficients after the first shift operation based on the transformation tree structure to obtain a reconstructed attribute value corresponding to the point cloud to be decoded; the reordered points to be decoded are determined based on the reconstructed geometric information of the point cloud to be decoded obtained by decoding the target code stream;

The second shift module is used to perform a second shift operation on the reconstructed attribute value corresponding to the point cloud to be decoded according to the target shift number to obtain the reconstructed attribute information corresponding to the point cloud to be decoded; the shift direction of the second shift operation is opposite to the shift direction of the first shift operation.

In a fourth aspect, an attribute transformation encoding device is provided, comprising:

A reordering module, used for reordering the point cloud to be encoded based on the acquired geometric information of the point cloud to be encoded;

A first shift module, configured to perform a first shift operation on the attribute information of the reordered point cloud to be encoded according to a target shift number associated with the point cloud to be encoded;

A first processing module is used to construct a transformation tree structure corresponding to the point cloud to be encoded according to the geometric distances between the reordered points to be encoded, and transform the attribute information after the first shift operation is performed based on the transformation tree structure to obtain transformation coefficients corresponding to the point cloud to be encoded;

The second shift module is used to perform a second shift on the transformation coefficient corresponding to the point cloud to be encoded according to the target shift number. a shift operation, wherein a shift direction of the second shift operation is opposite to a shift direction of the first shift operation;

The second processing module is used to quantize and encode the transformation coefficients after the second shift operation is performed to generate a target code stream.

In a fifth aspect, a terminal is provided, which includes a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the method described in the first aspect are implemented, or the steps of the method described in the second aspect are implemented.

In a sixth aspect, a readable storage medium is provided, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps of the method described in the first aspect are implemented, or the steps of the method described in the second aspect are implemented.

In the seventh aspect, a chip is provided, comprising a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run a program or instruction to implement the method described in the first aspect, or to implement the steps of the method described in the second aspect.

In an eighth aspect, a computer program/program product is provided, wherein the computer program/program product is stored in a storage medium, and the computer program/program product is executed by at least one processor to implement the steps of the method described in the first aspect, or to implement the steps of the method described in the second aspect.

In the embodiment of the present application, the decoding end obtains the target shift number associated with the target code stream during decoding of the target code stream, the target shift number associated with the target code stream being the shift number used by the encoding end to perform the shift operation, and the shift operation is performed by using the target shift number, so that the shift number for the shift operation performed by the decoding end is the same as the shift number for the shift operation performed by the encoding end. Compared with the related art, in which the bit width of the value calculated by the decoding end may exceed the prescribed bit width upper limit, in the embodiment of the present application, the bit width of the value calculated by the decoding end is within the prescribed bit width range, thereby avoiding decoding errors.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the framework of a point cloud AVS point cloud encoding device;

FIG2 is a schematic diagram of the framework of a point cloud AVS point cloud decoding device;

FIG3 is a schematic diagram of a flow chart of an attribute transformation decoding method provided in an embodiment of the present application;

FIG4 is a schematic diagram of a flow chart of an attribute transformation encoding method provided in an embodiment of the present application;

FIG5 is a structural diagram of an attribute transformation decoding device provided in an embodiment of the present application;

FIG6 is a structural diagram of an attribute transformation encoding device provided in an embodiment of the present application;

FIG7 is a structural diagram of a communication device provided in an embodiment of the present application;

FIG8 is a schematic diagram of the hardware structure of a terminal provided in an embodiment of the present application.

Detailed ways

The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of this application.

The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first" and "second" are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and/or" in the specification and claims represents at least one of the connected objects, and the character "/" generally represents that the objects associated with each other are in an "or" relationship.

The attribute transformation encoding device corresponding to the attribute transformation encoding method in the embodiment of the present application and the attribute transformation decoding device corresponding to the attribute transformation decoding method can both be terminals, which can also be called terminal equipment or user terminal (User Equipment, UE). The terminal can be a mobile phone, a tablet computer (Tablet Personal Computer), a laptop computer (Laptop Computer) or a notebook computer, a personal digital assistant (Personal Digital Assistant, PDA), a handheld computer, a netbook, an ultra-mobile personal computer (ultra-mobile personal computer, UMPC), a mobile Internet device (Mobile Internet Device, MID), an augmented reality (augm Terminal side devices include augmented reality (AR)/virtual reality (VR) devices, robots, wearable devices (Wearable Device) or vehicle-mounted devices (VUE), pedestrian terminals (PUE), smart homes (home appliances with wireless communication functions, such as refrigerators, TVs, washing machines or furniture, etc.), game consoles, personal computers (personal computers, PCs), teller machines or self-service machines, etc., and wearable devices include: smart watches, smart bracelets, smart headphones, smart glasses, smart jewelry (smart bracelets, smart bracelets, smart rings, smart necklaces, smart anklets, smart anklets, etc.), smart wristbands, smart clothing, etc. It should be noted that the specific type of terminal 11 is not limited in the embodiments of the present application.

For ease of understanding, some contents involved in the embodiments of the present application are described below:

Please refer to FIG. 1. As shown in FIG. 1, currently, in the digital audio and video coding technology standard, the geometric information and attribute information of the point cloud are encoded separately using the point cloud AVS point cloud encoding device. First, the geometric information is converted into coordinates so that all the point clouds are contained in a bounding box, and then the coordinates are quantized. Quantization mainly plays a role in scaling. Since quantization rounds the geometric coordinates, the geometric information of some points is the same, which is called duplicate points. Whether to remove duplicate points is determined according to parameters. The two steps of quantization and removal of duplicate points are also called voxelization. Next, the bounding box is divided into a multi-tree, such as an octree, a quadtree or a binary tree. In the multi-tree-based geometric information encoding framework, the bounding box is divided into 8 equal sub-cubes, and the non-empty sub-cubes are divided until the division is stopped when the leaf node is a unit cube of 1x1x1, and the number of points in the leaf node is encoded to generate a binary code stream.

After the geometric encoding is completed, the geometric information is reconstructed for subsequent recoloring. Attribute encoding is mainly for color and reflectance information. First, determine whether to perform color space conversion based on the parameters. If color space conversion is performed, the color information is converted from the red green blue (RGB) color space to the luminance bandwidth chrominance (YUV) color space. Then, the original point cloud is used to recolor the geometrically reconstructed point cloud so that the unencoded attribute information corresponds to the reconstructed geometric information. In color information encoding, after sorting the point cloud using Morton code or Hilbert code, the geometric spatial relationship is used to search for the nearest neighbor of the point to be predicted, and the nearest neighbor is used to find the nearest neighbor of the point to be predicted. The reconstructed attribute value of the neighbor is used to predict the point to be predicted to obtain the predicted attribute value, and then the real attribute value and the predicted attribute value are differentiated to obtain the prediction residual, and finally the prediction residual is quantized and encoded to generate a binary code stream.

It should be understood that the decoding process in the digital audio and video coding technology standard corresponds to the above-mentioned encoding process. Specifically, the framework of the audio and video coding (Audio Video Coding Standard, AVS) point cloud decoding device is shown in Figure 2.

The present application provides an attribute transformation decoding method. The attribute transformation decoding method provided by the embodiment of the present application is described in detail below through some embodiments and application scenarios in combination with the accompanying drawings.

Please refer to Figure 3, which is a flow chart of the attribute transformation decoding method in an embodiment of the present application. The attribute transformation decoding method provided in this embodiment includes the following steps:

S301: A decoding end obtains a target bitstream and a target shift number associated with the target bitstream.

In this step, the decoder obtains the target bitstream and the target shift number associated with the target bitstream, wherein the target shift number associated with the target bitstream is the shift number used by the encoder in performing the shift operation. Optionally, the target shift number may be determined based on indication information carried in the target bitstream.

S302: The decoding end decodes and dequantizes the target bitstream to obtain reconstructed transform coefficients corresponding to the point cloud to be decoded.

S303: The decoding end performs a first shift operation on the reconstructed transformation coefficients corresponding to the to-be-decoded point cloud according to the target shift number.

In this step, the target code stream is decoded and dequantized to obtain the reconstructed transform coefficients corresponding to the point cloud to be decoded, and a first shift operation is performed on the reconstructed transform coefficients corresponding to the point cloud to be decoded, wherein the shift number of the first shift operation is the target shift number. Optionally, the first shift operation is a left shift operation, that is, a left shift operation is performed on the reconstructed transform coefficients to move the target shift number to the left.

S304, the decoding end constructs a transformation tree structure corresponding to the point cloud to be decoded according to the geometric distances between the reordered points to be decoded, and performs an inverse transformation on the reconstructed transformation coefficients after the first shift operation based on the transformation tree structure to obtain the reconstructed attribute values corresponding to the point cloud to be decoded.

It should be understood that in the above process of decoding the target code stream, the reconstructed geometric information of the point cloud to be decoded will also be obtained, and then the point cloud to be decoded will be reordered based on the reconstructed geometric information of the point cloud to be decoded, and the transformation tree structure corresponding to the point cloud to be decoded is constructed according to the geometric distance between the reordered points to be decoded. The above transformation tree structure includes multiple structural layers, and each structural layer includes multiple nodes.

In this step, the reconstructed transform coefficients after the first shift operation can be inversely transformed by the transformation matrix to obtain the reconstructed attribute value corresponding to the point cloud to be decoded. For a node that does not have a parent node in the transformation tree structure, the first attribute coefficient corresponding to the node can be predicted to obtain a predicted attribute value, and then the sum of the reconstructed transform coefficient corresponding to the node and the predicted attribute value is determined as the reconstructed attribute value corresponding to the node, and the reconstructed attribute value corresponding to each node in the transformation tree structure is determined in the above manner. Among them, the reconstructed transform coefficient corresponding to the above node is the reconstructed transform coefficient after the first shift operation is performed.

S305: The decoding end performs a second shift operation on the reconstructed attribute value corresponding to the to-be-decoded point cloud according to the target shift number to obtain reconstructed attribute information corresponding to the to-be-decoded point cloud.

In this step, after obtaining the reconstructed attribute value corresponding to the point cloud to be decoded, a second shift operation can be performed on the reconstructed attribute value corresponding to the point cloud to be decoded to obtain the reconstructed attribute information corresponding to the point cloud to be decoded, that is, a second shift operation is performed on the reconstructed attribute value corresponding to each node to obtain the reconstructed attribute information corresponding to each node, thereby completing the decoding of the point cloud to be decoded. The shift number of the second shift operation is the target shift number. Optionally, the shift direction of the second shift operation is opposite to the shift direction of the first shift operation. When the first shift operation is a left shift operation, the second shift operation is a right shift operation.

In the embodiment of the present application, the decoding end obtains the target shift number associated with the target code stream during decoding of the target code stream, and performs a shift operation according to the target shift number, so that the shift number of the shift operation performed by the decoding end is the same as the shift number of the shift operation performed by the encoding end. Compared with the related art, the bit width of the value calculated by the decoding end may exceed the prescribed bit width upper limit. In the embodiment of the present application, the bit width of the value calculated by the decoding end is within the prescribed bit width range, thereby avoiding decoding errors.

Optionally, the target shift number is a shift number agreed upon by a protocol, or the target shift number is determined based on indication information carried in the target code stream.

An optional implementation is: the target shift number is the shift number agreed upon by the protocol. In this implementation, a parameter may be specified at the decoding end, and the parameter is used to characterize the target shift number.

Another optional implementation is: the target shift number is determined by indication information carried in the target bitstream. In this implementation, the target bitstream is decoded to obtain the indication information, and the target shift number is determined according to the indication information.

Optionally, the target value is determined based on a preset bit width value, a bit width value of attribute information corresponding to the point cloud to be decoded, and the number of points to be decoded included in the point cloud to be decoded.

Optionally, the target shift number is greater than or equal to 0 and less than or equal to the target value;

Among them, the target value is the target difference divided by 2, the target difference is the difference between the first value and the second value, the first value is the difference between the preset bit width value and the bit width value of the attribute information corresponding to the point cloud to be decoded, and the second value is the value after performing a logarithmic operation on the number of points to be decoded included in the point cloud to be decoded.

In this embodiment, the target shift number needs to satisfy the following formula:
N*2 ⁿ *2 ^kFracBits *2 ^kFracBits ≤2 ^m

Among them, KFracBits represents the target shift bit number, N represents the number of points to be decoded included in the point cloud to be decoded, n represents the bit width value of the attribute information corresponding to the point cloud to be decoded, and m represents the preset bit width value.

By transforming the above formula, we can get the following formula, and then use the following formula to limit the value range of the target shift number:
0≤kFracBits≤(mn-log ₂ N)/2

Among them, KFracBits represents the target shift number, m represents the preset bit width value, optionally, m represents the bit width of the direct current (DC) coefficient corresponding to the point to be encoded in the point cloud to be decoded, n represents the bit width value of the attribute information corresponding to the point cloud to be decoded, and N represents the number of points to be decoded included in the point cloud to be decoded.

Wherein, (mn-log ₂ N)/2 represents the target value, (mn-log ₂ N) represents the target difference, (mn) represents the first value, and log ₂ N represents the second value.

Optionally, the target value is an integer obtained by rounding down the ratio of the target difference value to 2.

It should be understood that the higher the value of the target shift number, the higher the calculation accuracy. An optional implementation method is to determine the maximum integer within the value range of the target shift number by the following formula:
kFracBits = floor((mn-log ₂ N)/2)

Among them, KFracBits represents the target shift bit number, m represents the preset bit width value, optionally, m represents the bit width of the DC coefficient corresponding to the point to be encoded in the point cloud to be decoded, n represents the bit width value of the attribute information corresponding to the point cloud to be decoded, N represents the number of points to be decoded included in the point cloud to be decoded, floor represents the rounding down operation, and (mn-log ₂ N) represents the target difference.

In this embodiment, by limiting the specific value of the target shift number, the bit width of the value calculated by the decoding end is within the specified bit width range, thereby avoiding decoding errors.

Please refer to Figure 4, which is a flow chart of the attribute transformation coding method provided by an embodiment of the present application. The attribute transformation coding method provided by this embodiment includes the following steps:

S401: The encoding end reorders the point cloud to be encoded based on the acquired geometric information of the point cloud to be encoded.

S402: The encoding end performs a first shift operation on the attribute information of the reordered point cloud to be encoded according to a target shift number associated with the point cloud to be encoded.

In this step, after the code points are reordered, a first shift operation may be performed on the attribute information of the code point cloud, wherein the shift number of the first shift operation is the target shift number. Optionally, the first shift operation is a left shift operation.

S403, the encoding end constructs a transformation tree structure corresponding to the point cloud to be encoded according to the geometric distances between the reordered points to be encoded, and transforms the attribute information after the first shift operation based on the transformation tree structure to obtain transformation coefficients corresponding to the point cloud to be encoded.

In this step, the attribute information after the first shift operation can be transformed by a transformation matrix to obtain the transformation coefficients corresponding to the point cloud to be encoded. For nodes without a parent node in the transformation tree structure, attribute prediction is performed on them to obtain their DC coefficient prediction values, and then the DC residual coefficients are obtained.

It should be understood that the transformation process in this step is the inverse process of the inverse transformation process performed on the reconstructed transformation coefficients in the above embodiment, and will not be repeated here.

S404: The encoding end performs a second shift operation on the transformation coefficients corresponding to the point cloud to be encoded according to the target shift number.

The shifting direction of the second shifting operation is opposite to the shifting direction of the first shifting operation.

S405: The encoding end quantizes and encodes the transformation coefficients after performing the second shift operation to generate a target bit stream.

In an embodiment of the present application, the encoding end performs a first shift operation on the attribute information of the reordered point cloud to be encoded based on a target shift number associated with the point cloud to be encoded. Optionally, the target shift number is a shift number agreed upon by the protocol, or the target shift number is determined based on pre-acquired indication information.

It should be noted that the attribute transformation encoding method provided in this embodiment is the inverse process of the attribute transformation decoding provided in the above embodiment.

Optionally, the target value is based on a preset bit width value and a bit width value of the attribute information corresponding to the point cloud to be encoded. And the number of points to be encoded included in the point cloud to be encoded is determined.

Optionally, the target shift number is greater than or equal to 0 and less than or equal to the target value;

Among them, the target value is the target difference divided by 2, the target difference is the difference between the first value and the second value, the first value is the difference between the preset bit width value and the bit width value of the attribute information corresponding to the point cloud to be encoded, and the second value is the value after performing a logarithmic operation on the number of points to be encoded included in the point cloud to be encoded.

Optionally, the target value is an integer obtained by rounding down the ratio of the target value to 2.

It should be understood that the limitation of the value range of the target shift number at the encoding end in this embodiment is consistent with the solution at the decoding end, and will not be repeated here.

The attribute transformation decoding method provided in the embodiment of the present application may be executed by an attribute transformation decoding device. In the embodiment of the present application, the attribute transformation decoding device performing the attribute transformation decoding method is taken as an example to illustrate the attribute transformation decoding device provided in the embodiment of the present application.

As shown in FIG5 , the embodiment of the present application further provides an attribute transformation decoding device 500, including:

An acquisition module 501 is used to acquire a target bitstream and a target shift number associated with the target bitstream, where the target shift number associated with the target bitstream is the shift number used by the encoder to perform a shift operation;

The first processing module 502 is used to decode and dequantize the target bitstream to obtain reconstruction transformation coefficients corresponding to the point cloud to be decoded;

A first shift module 503, configured to perform a first shift operation on the reconstructed transformation coefficients corresponding to the to-be-decoded point cloud according to the target shift number;

The second processing module 504 is used to construct a transformation tree structure corresponding to the point cloud to be decoded according to the geometric distances between the reordered points to be decoded, and perform inverse transformation processing on the reconstructed transformation coefficients after the first shift operation based on the transformation tree structure to obtain a reconstructed attribute value corresponding to the point cloud to be decoded; the reordered points to be decoded are determined based on the reconstructed geometric information of the point cloud to be decoded obtained by decoding the target bitstream;

The second shift module 505 is used to perform a second shift operation on the reconstructed attribute value corresponding to the point cloud to be decoded according to the target shift number to obtain the reconstructed attribute information corresponding to the point cloud to be decoded; the shift direction of the second shift operation is opposite to the shift direction of the first shift operation.

Optionally, the target shift number is a shift number agreed upon by a protocol, or the target shift number is determined based on indication information carried in the target code stream.

Optionally, the target value is determined based on a preset bit width value, a bit width value of attribute information corresponding to the point cloud to be decoded, and the number of points to be decoded included in the point cloud to be decoded.

Optionally, the target shift number is greater than or equal to 0 and less than or equal to the target value;

Among them, the target value is the target difference divided by 2, the target difference is the difference between the first value and the second value, the first value is the difference between the preset bit width value and the bit width value of the attribute information corresponding to the point cloud to be decoded, and the second value is the value after performing a logarithmic operation on the number of points to be decoded included in the point cloud to be decoded.

Optionally, the target value is an integer obtained by rounding down the ratio of the target difference value to 2.

In the embodiment of the present application, the decoding end obtains the target shift number associated with the target code stream during the process of decoding the target code stream. Among them, the target shift number associated with the target code stream is the shift number used by the encoder to perform the shift operation, and the shift operation is performed by the target shift number, so that the shift number used by the decoder to perform the shift operation is the same as the shift number used by the encoder to perform the shift operation. Compared with the related art, the bit width of the value calculated by the decoder may exceed the specified bit width upper limit. In the embodiment of the present application, the bit width of the value calculated by the decoder is within the specified bit width range, thereby avoiding decoding errors.

This device embodiment corresponds to the attribute transformation decoding method embodiment shown in FIG. 3 . All implementation processes and implementation methods on the decoding end in the above method embodiment are applicable to this device embodiment and can achieve the same technical effect.

The attribute transformation coding method provided in the embodiment of the present application may be executed by an attribute transformation coding device. In the embodiment of the present application, an attribute transformation coding device executing the attribute transformation coding method is taken as an example to illustrate the attribute transformation coding device provided in the embodiment of the present application.

As shown in FIG6 , the embodiment of the present application further provides an attribute transformation encoding device 600, including:

A reordering module 601 is used to reorder the point cloud to be encoded based on the acquired geometric information of the point cloud to be encoded;

A first shift module 602, configured to perform a first shift operation on the attribute information of the reordered point cloud to be encoded according to a target shift number associated with the point cloud to be encoded;

The first processing module 603 is used to construct a transformation tree structure corresponding to the point cloud to be encoded according to the geometric distances between the reordered points to be encoded, and transform the attribute information after the first shift operation is performed based on the transformation tree structure to obtain transformation coefficients corresponding to the point cloud to be encoded;

A second shift module 604 is configured to perform a second shift operation on the transformation coefficients corresponding to the to-be-encoded point cloud according to the target shift number, wherein the shift direction of the second shift operation is opposite to the shift direction of the first shift operation;

The second processing module 605 is used to quantize and encode the transformation coefficients after the second shift operation is performed to generate a target bit stream.

Optionally, the target shift number is a shift number agreed upon by a protocol, or the target shift number is determined based on pre-acquired indication information.

Optionally, the target value is determined based on a preset bit width value, a bit width value of attribute information corresponding to the point cloud to be encoded, and the number of points to be encoded included in the point cloud to be encoded.

Optionally, the target shift number is greater than or equal to 0 and less than or equal to a target value; wherein the target value is a target difference divided by 2, the target difference is a difference between a first value and a second value, the first value is a difference between a preset bit width value and a bit width value of attribute information corresponding to the point cloud to be decoded, and the second value is a value obtained by performing a logarithmic operation on the number of points to be decoded included in the point cloud to be decoded.

Optionally, the target value is an integer obtained by rounding down the ratio of the target difference value to 2.

The attribute transformation coding device provided in the embodiment of the present application can implement each process implemented by the method embodiment of Figure 4 and achieve the same technical effect. To avoid repetition, it will not be described here.

The attribute transformation encoding device and the attribute transformation decoding device in the embodiment of the present application can be an electronic device, such as an electronic device with an operating system, or a component in the electronic device, such as an integrated circuit or a chip. The terminal may be a terminal, or other devices other than the terminal. For example, the terminal may include but is not limited to the types of terminals listed above, and other devices may be a server, a network attached storage (NAS), etc., which are not specifically limited in the embodiments of the present application.

Optionally, as shown in Figure 7, an embodiment of the present application also provides a communication device 700, including a processor 701 and a memory 702, and the memory 702 stores a program or instruction that can be executed on the processor 701. For example, when the communication device 700 is a terminal, the program or instruction is executed by the processor 701 to implement the various steps of the above-mentioned attribute transformation encoding method embodiment, or to implement the various steps of the above-mentioned attribute transformation decoding method embodiment, and can achieve the same technical effect.

The embodiment of the present application further provides a terminal, including a processor and a communication interface, wherein the processor is configured to perform the following operations:

Acquire a target bitstream and a target shift number associated with the target bitstream;

Decoding and dequantizing the target bitstream to obtain reconstruction transform coefficients corresponding to the point cloud to be decoded;

Performing a first shift operation on the reconstructed transformation coefficients corresponding to the to-be-decoded point cloud according to the target shift number;

According to the geometric distances between the reordered points to be decoded, a transformation tree structure corresponding to the point cloud to be decoded is constructed, and based on the transformation tree structure, an inverse transformation process is performed on the reconstructed transformation coefficients after the first shift operation is performed to obtain a reconstructed attribute value corresponding to the point cloud to be decoded;

A second shift operation is performed on the reconstructed attribute value corresponding to the to-be-decoded point cloud according to the target shift number to obtain reconstructed attribute information corresponding to the to-be-decoded point cloud.

Alternatively, the processor is used to perform the following operations:

Reordering the point cloud to be encoded based on the acquired geometric information of the point cloud to be encoded;

Performing a first shift operation on the attribute information of the reordered point cloud to be encoded according to a target shift number associated with the point cloud to be encoded;

According to the geometric distances between the reordered points to be encoded, a transformation tree structure corresponding to the point cloud to be encoded is constructed, and based on the transformation tree structure, the attribute information after the first shift operation is performed is transformed to obtain a transformation coefficient corresponding to the point cloud to be encoded;

Performing a second shift operation on the transform coefficients corresponding to the to-be-encoded point cloud according to the target shift number;

The transform coefficients after the second shift operation are quantized and encoded to generate a target bit stream.

The terminal embodiment corresponds to the above-mentioned terminal side method embodiment, and each implementation process and implementation mode of the above-mentioned method embodiment can be applied to the terminal embodiment and can achieve the same technical effect. Specifically, Figure 8 is a schematic diagram of the hardware structure of a terminal implementing the embodiment of the present application.

The terminal 800 includes but is not limited to: a radio frequency unit 801, a network module 802, an audio output unit 803, an input unit 804, a sensor 805, a display unit 806, a user input unit 807, an interface unit 808, a memory 809, and a processor 810.

Those skilled in the art will appreciate that the terminal 800 may also include a power source (such as a battery) for supplying power to various components, and the power source may be logically connected to the processor 810 through a power management system, so that the power management system can manage charging, discharging, and power consumption. The present invention may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently, which will not be described in detail here.

It should be understood that in the embodiment of the present application, the input unit 804 may include a graphics processing unit (GPU) 8041 and a microphone 8042, and the graphics processor 8041 processes the image data of the static picture or video obtained by the image capture device (such as a camera) in the video capture mode or the image capture mode. The display unit 806 may include a display panel 8061, and the display panel 8061 may be configured in the form of a liquid crystal display, an organic light emitting diode, etc. The user input unit 807 includes a touch panel 8071 and at least one of other input devices 8072. The touch panel 8071 is also called a touch screen. The touch panel 8071 may include two parts: a touch detection device and a touch controller. Other input devices 8072 may include, but are not limited to, a physical keyboard, function keys (such as a volume control key, a switch key, etc.), a trackball, a mouse, and a joystick, which will not be repeated here.

In the embodiment of the present application, after receiving downlink data from the network side device, the RF unit 801 can transmit the data to the processor 88 for processing; the RF unit 801 can send uplink data to the network side device. Generally, the RF unit 801 includes but is not limited to an antenna, an amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, etc.

The memory 809 can be used to store software programs or instructions and various data. The memory 809 may mainly include a first storage area for storing programs or instructions and a second storage area for storing data, wherein the first storage area may store an operating system, an application program or instruction required for at least one function (such as a sound playback function, an image playback function, etc.), etc. In addition, the memory 809 may include a volatile memory or a non-volatile memory, or the memory 809 may include both volatile and non-volatile memories. Among them, the non-volatile memory may 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 may be a random access memory (RAM), a static random access memory (SRAM), a dynamic random access memory (DRAM), a synchronous dynamic random access memory (SDRAM), a double data rate synchronous dynamic random access memory (DDRSDRAM), an enhanced synchronous dynamic random access memory (ESDRAM), a synchronous link dynamic random access memory (SLDRAM) and a direct memory bus random access memory (DRRAM). The memory 809 in the embodiment of the present application includes but is not limited to these and any other suitable types of memory.

The processor 810 may include one or more processing units; optionally, the processor 810 integrates an application processor and a modem processor, wherein the application processor mainly processes operations related to an operating system, a user interface, and application programs, and the modem processor mainly processes wireless communication signals, such as a baseband processor. It is understandable that the modem processor may not be integrated into the processor 810.

The processor 810 is configured to perform the following operations:

Acquire a target bitstream and a target shift number associated with the target bitstream;

Decoding and dequantizing the target bitstream to obtain reconstruction transform coefficients corresponding to the point cloud to be decoded;

Performing a first shift operation on the reconstructed transformation coefficients corresponding to the to-be-decoded point cloud according to the target shift number;

According to the geometric distances between the reordered points to be decoded, a transformation tree structure corresponding to the point cloud to be decoded is constructed, and the transformation tree structure corresponding to the point cloud to be decoded is constructed. Performing an inverse transform process on the reconstructed transform coefficients after the first shift operation in the transform tree structure to obtain a reconstructed attribute value corresponding to the point cloud to be decoded;

A second shift operation is performed on the reconstructed attribute value corresponding to the to-be-decoded point cloud according to the target shift number to obtain reconstructed attribute information corresponding to the to-be-decoded point cloud.

Alternatively, the processor 810 is further configured to perform the following operations:

Reordering the point cloud to be encoded based on the acquired geometric information of the point cloud to be encoded;

Performing a first shift operation on the attribute information of the reordered point cloud to be encoded according to a target shift number associated with the point cloud to be encoded;

According to the geometric distances between the reordered points to be encoded, a transformation tree structure corresponding to the point cloud to be encoded is constructed, and based on the transformation tree structure, the attribute information after the first shift operation is performed is transformed to obtain a transformation coefficient corresponding to the point cloud to be encoded;

Performing a second shift operation on the transform coefficients corresponding to the to-be-encoded point cloud according to the target shift number;

The transform coefficients after the second shift operation are quantized and encoded to generate a target bit stream.

The embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the various processes of the above-mentioned attribute transformation encoding method embodiment are implemented, or the various processes of the above-mentioned attribute transformation decoding method embodiment are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

The processor is the processor in the terminal described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of the above-mentioned attribute transformation encoding method embodiment, or to implement the various processes of the above-mentioned attribute transformation decoding method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

The embodiments of the present application further provide a computer program/program product, which is stored in a storage medium, and is executed by at least one processor to implement the various processes of the above-mentioned attribute transformation encoding method embodiment, or to implement the various processes of the above-mentioned attribute transformation decoding method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprises a..." does not exclude the existence of other identical elements in the process, method, article or device that includes the element. In addition, it should be pointed out that However, the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the relevant technology, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, computer, server, air conditioner, or network equipment, etc.) to execute the methods described in each embodiment of the present application.

The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims (22)

1. An attribute transformation decoding method, comprising:

   The decoding end obtains a target bitstream and a target shift number associated with the target bitstream, where the target shift number associated with the target bitstream is the shift number used by the encoding end to perform a shift operation;

   The decoding end decodes and dequantizes the target bitstream to obtain reconstruction transformation coefficients corresponding to the point cloud to be decoded;

   The decoding end performs a first shift operation on the reconstructed transformation coefficients corresponding to the to-be-decoded point cloud according to the target shift number;

   The decoding end constructs a transformation tree structure corresponding to the point cloud to be decoded according to the geometric distances between the reordered points to be decoded, and performs inverse transformation processing on the reconstructed transformation coefficients after the first shift operation based on the transformation tree structure to obtain a reconstructed attribute value corresponding to the point cloud to be decoded; the reordered points to be decoded are determined based on the reconstructed geometric information of the point cloud to be decoded obtained by decoding the target bitstream;

   The decoding end performs a second shift operation on the reconstructed attribute value corresponding to the point cloud to be decoded according to the target shift number to obtain the reconstructed attribute information corresponding to the point cloud to be decoded; the shift direction of the second shift operation is opposite to the shift direction of the first shift operation.
2. The method according to claim 1, wherein the target shift number is a shift number agreed upon by a protocol, or the target shift number is determined based on indication information carried in the target code stream.
3. The method according to claim 1 or 2, wherein the target value is determined based on a preset bit width value, a bit width value of the attribute information corresponding to the point cloud to be decoded, and the number of points to be decoded included in the point cloud to be decoded.
4. The method according to claim 3, wherein the target shift number is greater than or equal to 0 and less than or equal to the target value;

   Among them, the target value is the target difference divided by 2, the target difference is the difference between the first value and the second value, the first value is the difference between the preset bit width value and the bit width value of the attribute information corresponding to the point cloud to be decoded, and the second value is the value after performing a logarithmic operation on the number of points to be decoded included in the point cloud to be decoded.
5. The method according to claim 4, wherein the target value is an integer obtained by rounding down the ratio of the target difference value to 2.
6. An attribute transformation encoding method, comprising:

   The encoding end reorders the point cloud to be encoded based on the acquired geometric information of the point cloud to be encoded;

   The encoding end performs a first shift operation on the attribute information of the reordered point cloud to be encoded according to a target shift number associated with the point cloud to be encoded;

   The encoder constructs a transformation tree structure corresponding to the point cloud to be encoded according to the geometric distances between the reordered points to be encoded, and transforms the attribute information after the first shift operation based on the transformation tree structure to obtain transformation coefficients corresponding to the point cloud to be encoded;

   The encoder performs a second shift operation on the transform coefficients corresponding to the to-be-encoded point cloud according to the target shift number, where a shift direction of the second shift operation is opposite to a shift direction of the first shift operation;

   The encoding end quantizes and encodes the transformation coefficients after the second shift operation is performed to generate a target code stream.
7. The method according to claim 6, wherein the target shift number is a shift number agreed upon by a protocol, or the target shift number is determined based on pre-acquired indication information.
8. The method according to claim 6 or 7, wherein the target value is determined based on a preset bit width value, a bit width value of the attribute information corresponding to the point cloud to be encoded, and the number of points to be encoded included in the point cloud to be encoded.
9. The method according to claim 8, wherein the target shift number is greater than or equal to 0 and less than or equal to the target value;

   Among them, the target value is the target difference divided by 2, the target difference is the difference between the first value and the second value, the first value is the difference between the preset bit width value and the bit width value of the attribute information corresponding to the point cloud to be encoded, and the second value is the value after performing a logarithmic operation on the number of points to be encoded included in the point cloud to be encoded.
10. The method according to claim 9, wherein the target value is an integer obtained by rounding down the ratio of the target difference value to 2.
11. An attribute transformation decoding device, comprising:

    An acquisition module, used to acquire a target bitstream and a target shift number associated with the target bitstream, where the target shift number associated with the target bitstream is the shift number used by the encoder to perform a shift operation;

    A first processing module is used to decode and dequantize the target bitstream to obtain reconstruction transformation coefficients corresponding to the point cloud to be decoded;

    A first shift module, configured to perform a first shift operation on the reconstructed transformation coefficients corresponding to the to-be-decoded point cloud according to the target shift number;

    A second processing module is used to construct a transformation tree structure corresponding to the point cloud to be decoded according to the geometric distances between the reordered points to be decoded, and to perform inverse transformation processing on the reconstructed transformation coefficients after the first shift operation based on the transformation tree structure to obtain a reconstructed attribute value corresponding to the point cloud to be decoded; the reordered points to be decoded are determined based on the reconstructed geometric information of the point cloud to be decoded obtained by decoding the target code stream;

    The second shift module is used to perform a second shift operation on the reconstructed attribute value corresponding to the point cloud to be decoded according to the target shift number to obtain the reconstructed attribute information corresponding to the point cloud to be decoded; the shift direction of the second shift operation is opposite to the shift direction of the first shift operation.
12. The apparatus according to claim 11, wherein the target shift number is a shift number agreed upon by a protocol, or the target shift number is determined based on indication information carried in the target code stream.
13. The device according to claim 11 or 12, wherein the target value is determined based on a preset bit width value, a bit width value of the attribute information corresponding to the point cloud to be decoded, and the number of points to be decoded included in the point cloud to be decoded.
14. The device according to claim 13, wherein the target shift number is greater than or equal to 0 and less than or equal to the target value;

    Among them, the target value is the target difference divided by 2, the target difference is the difference between the first value and the second value, the first value is the difference between the preset bit width value and the bit width value of the attribute information corresponding to the point cloud to be decoded, and the second value is the value after performing a logarithmic operation on the number of points to be decoded included in the point cloud to be decoded.
15. The device according to claim 14, wherein the target value is an integer obtained by rounding down the ratio between the target difference and 2.
16. An attribute transformation encoding device, comprising:

    A reordering module, used for reordering the point cloud to be encoded based on the acquired geometric information of the point cloud to be encoded;

    A first shift module, configured to perform a first shift operation on the attribute information of the reordered point cloud to be encoded according to a target shift number associated with the point cloud to be encoded;

    A first processing module is used to construct a transformation tree structure corresponding to the point cloud to be encoded according to the geometric distances between the reordered points to be encoded, and transform the attribute information after the first shift operation is performed based on the transformation tree structure to obtain transformation coefficients corresponding to the point cloud to be encoded;

    A second shift module, configured to perform a second shift operation on the transformation coefficients corresponding to the to-be-encoded point cloud according to the target shift number, wherein a shift direction of the second shift operation is opposite to a shift direction of the first shift operation;

    The second processing module is used to quantize and encode the transformation coefficients after the second shift operation is performed to generate a target code stream.
17. The apparatus according to claim 16, wherein the target shift number is a shift number agreed upon by a protocol, or the target shift number is determined based on pre-acquired indication information.
18. The device according to claim 16 or 17, wherein the target value is determined based on a preset bit width value, a bit width value of the attribute information corresponding to the point cloud to be encoded, and the number of points to be encoded included in the point cloud to be encoded.
19. The device according to claim 18, wherein the target shift number is greater than or equal to 0 and less than or equal to the target value;

    Among them, the target value is the target difference divided by 2, the target difference is the difference between the first value and the second value, the first value is the difference between the preset bit width value and the bit width value of the attribute information corresponding to the point cloud to be encoded, and the second value is the value after performing a logarithmic operation on the number of points to be encoded included in the point cloud to be encoded.
20. The device according to claim 19, wherein the target value is an integer obtained by rounding down the ratio between the target difference and 2.
21. A terminal comprises a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the attribute transformation decoding method described in any one of claims 1 to 5 are implemented, or the steps of the attribute transformation encoding method described in any one of claims 6 to 10 are implemented.
22. A readable storage medium stores a program or instruction, and when the program or instruction is executed by a processor, the program or instruction implements the steps of the attribute transformation decoding method according to any one of claims 1 to 5, or implements the steps of the attribute transformation encoding method according to any one of claims 6 to 10.