WO2019001015A1

WO2019001015A1 - Method and device for encoding and decoding image data

Info

Publication number: WO2019001015A1
Application number: PCT/CN2018/078837
Authority: WO
Inventors: 赵寅; 杨海涛; 刘杉
Original assignee: 华为技术有限公司
Priority date: 2017-06-28
Filing date: 2018-03-13
Publication date: 2019-01-03
Also published as: TW201906415A; CN109151477B; CN109151477A; TWI667914B

Abstract

The present application relates to the field of image processing and addresses the problem of high coding complexity. Disclosed in embodiments of the present application are a method and device for encoding and decoding image data. The method of decoding image data particularly comprises: obtaining a code stream containing image data; parsing the code stream to obtain node dividing scheme information of a first-level coding tree; parsing the code stream to obtain node dividing scheme information of a second-level coding tree; if the node dividing scheme information of the second-level coding tree indicates that a dividing scheme corresponding to a first node in the second-level coding tree is a ternary tree division, parsing the code stream to obtain coding information of three sub-nodes of the first node, wherein each sub-node of the first node corresponds to one coding unit; and according to the coding information of the three sub-nodes of the first node, decoding and reconstructing the coding unit to obtain an image of corresponding image data.

Description

Method and device for encoding and decoding image data

The present application claims priority to Chinese Patent Application No. 200910509100.0, entitled "A Method for Encoding, Decoding, and Decoding of Image Data", filed on June 28, 2017, the entire contents of which are incorporated by reference. In this application.

Technical field

The embodiments of the present invention relate to the field of image processing, and in particular, to a method and an apparatus for encoding and decoding image data.

Background technique

The video codec standard H.265 divides a frame of image into Coding Tree Units (CTUs) that do not overlap each other, and uses each CTU as the root node of a Quad-Tree (QT) according to QT. The structure recursively divides each CTU into several leaf nodes. Each node in the QT structure corresponds to an image area. If a node is no longer divided, the node is called a leaf node, and its corresponding image area forms a coding unit (CU). Therefore, H.265 can be considered as a process of dividing a CTU into a group of CUs. The division of the CTU into a group of CUs corresponds to a coding tree.

The Joint Exploration Team on Future Video Coding (JVET) reference software Joint Exploration Model (JEM) proposed the QTBT division method, that is, the nodes in the first-level coding tree adopt the QT division method. The nodes in the second-level coding tree adopt the Binary Tree (BT) division method (the BT division method includes "horizontal dichotomy" and "vertical dichotomy"). Specifically, the CTU is first divided according to the QT division manner to obtain a plurality of QT leaf nodes; the leaf nodes of the QT may be divided according to the BT division manner. In the QTBT division mode, the CU shape is more diverse and can better adapt to the content of the partial image.

However, for each node, the encoding end device usually needs to calculate the Rate Distortion Cost (RD cost) for each partitioning method that the node can use, compare the calculated RD cost, and the smallest RD cost. The corresponding division mode is determined as the division manner of the node. Therefore, for each node, the coding end device needs to calculate the RD cost of multiple division modes, so that the coding complexity is high.

Summary of the invention

The embodiment of the present application provides a method and an apparatus for encoding and decoding image data, which can solve the problem of high coding complexity.

To achieve the above objective, the embodiment of the present application adopts the following technical solutions:

In a first aspect, a method for decoding image data is provided. After obtaining a code stream including image data, the decoding end device obtains node partitioning mode information of the first-level coding tree and a second-level coding tree by parsing the code stream. The node division mode information, if the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is a tri-tree partition, the decoding end device obtains the first node by parsing the code stream. The coding information of the three child nodes, one child node of the first node corresponds to one coding unit CU, so that the decoding end device can decode and reconstruct the coding unit according to the coding information of the three child nodes of the first node, and obtain corresponding image data. Image. In this application, the root node of the first-level coding tree corresponds to one CTU, and the leaf node of the first-level coding tree is performed by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree. Instructed, the root node of the second level coding tree is a leaf node of the first level coding tree.

The decoding end device in the embodiment of the present application only needs to determine that the partitioning manner corresponding to the first node is a tri-tree partition, and the encoding information of the three child nodes of the first node can be directly obtained, and the three child nodes of the first node need not be sequentially performed. Decoding is performed to speed up the decoding and reduce the complexity of decoding.

Optionally, in a possible implementation manner of the application, the node division manner corresponding to the first-level coding tree is different from the node division manner corresponding to the second-level coding tree.

Optionally, in another possible implementation manner of the present application, the node division manner corresponding to the first-level coding tree includes a quad-tree division, and the node division manner corresponding to the second-level coding tree includes a binary tree division and a tri-tree division .

In a second aspect, a decoding end device is provided, where the decoding end device includes an obtaining module, a parsing module, and a decoding rebuilding module. The obtaining module is configured to obtain a code stream that includes image data. The parsing module is configured to parse the code stream acquired by the acquiring module, and obtain node partitioning mode information of the first-level coding tree, where the root node of the first-level coding tree corresponds to a coding tree unit CTU, and the first-level coding tree The leaf node is indicated by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree, and is used for parsing the code stream to obtain the node division manner of the second-level coding tree. Information, wherein a root node of the second-level coding tree is a leaf node of the first-level coding tree, and information for the node division mode of the second-level coding tree indicates that the first node in the second-level coding tree corresponds to The division mode is a tri-tree division, and the code stream is parsed to obtain coding information of three child nodes of the first node, wherein one child node of the first node corresponds to one coding unit CU. The decoding reconstruction module is configured to perform decoding and reconstruction on the coding unit according to the coding information of the three child nodes of the first node obtained by the analysis module, to obtain an image corresponding to the image data.

For a detailed description of the second aspect and various implementations of the present application, reference may be made to the detailed description of the first aspect and various implementations thereof; and the beneficial effects of the second aspect and various implementations thereof may be referred to The analysis of the beneficial effects on the one hand and its various implementations will not be repeated here.

In a third aspect, a method for decoding image data is provided. After obtaining a code stream containing image data, the decoding end device obtains node partitioning mode information of the first-level coding tree and the second-level coding tree by parsing the code stream. The node division mode information, if the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is not continued to be divided according to the division manner of the second-level coding tree, the decoding end device The node division mode information of the third-level coding tree is obtained by parsing the code stream; if the node division mode information of the third-level coding tree indicates that the division manner corresponding to the first node is a tri-tree division, the decoding end device parses the code stream, The coding information of the three child nodes of the first node is obtained, and one child node of the first node corresponds to one coding unit CU, so that the decoding end device can decode and reconstruct the coding unit according to the coding information of the three child nodes of the first node. , an image corresponding to the image data is obtained. In this application, the root node of the first-level coding tree corresponds to one CTU, and the leaf node of the first-level coding tree is performed by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree. Instructed, the root node of the second-level coding tree is a leaf node of the first-level coding tree, and the first node is a root node of the third-level coding tree.

Optionally, in a possible implementation manner of the present application, the node division manner corresponding to the first-level coding tree includes a quad-tree division, and the node division manner corresponding to the second-level coding tree includes a binary tree division, and the third-level coding The corresponding node division manner includes a tri-tree division.

In a fourth aspect, a decoding end device is provided, where the decoding end device includes an obtaining module, a parsing module, and a decoding rebuilding module. The obtaining module is configured to obtain a code stream that includes image data. The parsing module is configured to parse the code stream acquired by the acquiring module, and obtain node partitioning mode information of the first-level coding tree, where the root node of the first-level coding tree corresponds to a coding tree unit CTU, and the first-level coding tree The leaf node is indicated by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree, and is used for parsing the code stream to obtain the node division manner of the second-level coding tree. Information, wherein a root node of the second-level coding tree is a leaf node of the first-level coding tree, and information for the node division mode of the second-level coding tree indicates that the first node in the second-level coding tree corresponds to The division mode is not to continue to divide according to the division manner of the second-level coding tree, and the code stream is parsed to obtain the node division manner information of the third-level coding tree, wherein the root node of the third-level coding tree is the first node, and If the node division mode information of the third-level coding tree indicates that the division manner corresponding to the first node is a tri-tree partition, the code stream is parsed, and the first node is obtained. Coding information child nodes, wherein a first node of the child node corresponding to one coding unit CU. The decoding reconstruction module is configured to perform decoding and reconstruction on the coding unit according to the coding information of the three child nodes of the first node obtained by the analysis module, to obtain an image corresponding to the image data.

For a detailed description of the fourth aspect of the present application and various implementations thereof, reference may be made to the detailed description in the third aspect and various implementation manners thereof; and the beneficial effects of the fourth aspect and various implementation manners thereof may be referred to The analysis of the beneficial effects in the three aspects and various implementations will not be repeated here.

In a fifth aspect, a decoding method for image data is provided. After obtaining a code stream including image data, the decoding end device parses the code stream to obtain a trigeminal leaf for indicating whether to limit the division of the trigeminal tree to continue dividing. a node mode identifier, node partitioning mode information of the first level coding tree, and node partitioning mode information of the second level coding tree, if the node partitioning mode information of the second level coding tree indicates the first node corresponding to the second level coding tree The division mode is a tri-tree division, and the tri-tree leaf node pattern identifier indicates that the node obtained by limiting the tri-tree division continues to be divided, and the decoding end device obtains the coding information of the three child nodes of the first node by parsing the code stream, and the first node One sub-node corresponds to one coding unit CU, so that the decoding end device can decode and reconstruct the coding unit according to the coding information of the three sub-nodes of the first node, and obtain an image corresponding to the image data. In this application, the root node of the first-level coding tree corresponds to one CTU, and the leaf node of the first-level coding tree is performed by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree. Instructed, the root node of the second level coding tree is a leaf node of the first level coding tree.

The embodiment of the present application adds a condition for restricting node division: if the division manner corresponding to the parent node of a node is a tri-tree division, the node does not continue to divide. The decoding end device only needs to determine that the corresponding division manner of a certain node is a tri-tree division, and the coding information of the child node of the node can be directly obtained, and the decoding of all the child nodes of the node is not required, thereby speeding up the decoding rate. Reduced the complexity of decoding. In addition, the decoding end device may determine the limitation of the node division according to the tri-tree leaf node mode identifier, thereby adaptively acquiring the node division information of each level coding tree.

In a sixth aspect, a decoding end device is provided, where the decoding end device includes an obtaining module, a parsing module, and a decoding rebuilding module. The obtaining module is configured to obtain a code stream that includes image data. The parsing module is configured to parse the code stream acquired by the acquiring module to obtain a tri-tree leaf node mode identifier, where the tri-tree leaf node mode identifier is used to indicate whether the node obtained by limiting the tri-tree partitioning is further divided, and is used for parsing the code stream. Obtaining node partitioning mode information of the first-level coding tree, where the root node of the first-level coding tree corresponds to one coding tree unit CTU, and the leaf node of the first-level coding tree is corresponding to the node division mode information of the first-level coding tree The node division manner is indicated by the root node of the first-level coding tree, and is used for parsing the code stream to obtain node division manner information of the second-level coding tree, wherein the root node of the second-level coding tree is the first level a leaf node of the coding tree, and a node division mode information for if the second level coding tree indicates that the first node corresponding to the second level coding tree corresponds to a trinomial division, and the trigeminal leaf node mode identifier indicates a restricted trigeminal The nodes obtained by the tree division continue to divide, parsing the code stream, and obtaining the coded letters of the three child nodes of the first node. Wherein a first node of the child node corresponding to one coding unit CU. The decoding reconstruction module is configured to perform decoding and reconstruction on the coding unit according to the coding information of the three child nodes of the first node obtained by the analysis module, to obtain an image corresponding to the image data.

For a detailed description of the sixth aspect and various implementation manners of the present application, reference may be made to the fifth aspect and the detailed description in the various implementation manners; and the beneficial effects of the sixth aspect and various implementation manners thereof may be referred to The analysis of the beneficial effects in the five aspects and various implementations will not be repeated here.

In a seventh aspect, a method for encoding image data is provided. After determining a CTU corresponding to an image block to be encoded, the encoding end device divides the CTU according to a node division manner corresponding to the first-level coding tree, to obtain a first-level coding. a leaf node of the tree, wherein the root node of the first-level coding tree corresponds to the CTU; the coding end device determines, according to the preset condition, a division manner that the first node in the second-level coding tree can use, and the second-level coding tree The root node is a leaf node of the first-level coding tree, and the preset condition includes: if the division mode corresponding to the parent node of the first node is a tri-tree division, determining that the first node is not divided; if the first node can use the division manner For no division, the encoding end device encodes the coding unit corresponding to the first node to obtain a coding unit code stream corresponding to the coding unit.

The preset condition in the embodiment of the present application limits the division of nodes in the second-level coding tree, and the corresponding division manner of a node in the second-level coding tree is a tri-tree division, and the child nodes of the node are no longer Continue to divide, thus greatly reducing the complexity of dividing the nodes in the second-level coding tree and reducing the coding complexity.

In addition, since the mapping manner of a node in the second-level coding tree is tri-tree partitioning, the child nodes of the node will not continue to be divided, so that the code stream sent by the encoding end device after encoding is no longer The division information including the child nodes of the node saves transmission bits and reduces the length of the code stream.

Optionally, in another possible implementation manner of the present application, if the partitioning manner that the first node can use does not include no partitioning, the encoding end device calculates, for each of the partitioning manners that the first node can use. The rate distortion cost is determined, and the division mode corresponding to the minimum rate distortion cost is determined as the target division mode corresponding to the first node, so that the coding end device can divide the first node by using the target division manner corresponding to the first node.

In an eighth aspect, an encoding end device is provided, the encoding end device comprising a determining module, a dividing module and an encoding module. The determining module is configured to determine a coding tree unit CTU corresponding to the image block to be encoded. The dividing module is configured to divide the CTU determined by the determining module according to a node partitioning manner corresponding to the first-level coding tree, to obtain a leaf node of the first-level coding tree, where the root node of the first-level coding tree corresponds to the CTU. The determining module is further configured to determine, according to a preset condition, a division manner that can be used by the first node in the second-level coding tree, where the preset condition includes: if the division manner corresponding to the parent node of the first node is a tri-tree division, It is determined that the first node is not divided, and the root node of the second-level coding tree is a leaf node of the first-level coding tree. The coding module is configured to: if the division manner that is determined by the determining module is not to be divided, the coding unit CU corresponding to the first node is encoded to obtain a coding unit code stream corresponding to the coding unit.

Optionally, in a possible implementation manner of the present application, the encoding end device provided by the embodiment of the present application further includes a computing module, where the calculating module is configured to: if the determining module determines that the first node is usable, the dividing manner is not included. Without division, the rate distortion cost of each of the division modes that the first node can use is calculated. The determining module is further configured to determine a partitioning manner corresponding to a minimum rate distortion cost as a target partitioning manner corresponding to the first node. The dividing module is specifically configured to divide the first node by using a target dividing manner corresponding to the first node determined by the determining module.

Optionally, in a possible implementation manner of the present application, the node division manner corresponding to the first-level coding tree includes a quad-tree division, and the node division manner corresponding to the second-level coding tree includes a binary tree division and a tri-tree division.

For a detailed description of the eighth aspect of the present application and various implementations thereof, reference may be made to the detailed description in the seventh aspect and various implementation manners thereof; and the beneficial effects of the eighth aspect and various implementation manners thereof may be referred to The analysis of the beneficial effects in the seven aspects and various implementations will not be repeated here.

According to a ninth aspect, a decoding end device is provided, wherein the decoding end device comprises: one or more processors, a memory, and a communication interface. The memory, communication interface is coupled to one or more processors; the memory is for storing computer program code, the computer program code comprising instructions, when the one or more processors execute the instructions, the decoding device performs the first aspect, The method for decoding image data according to the third aspect, the fourth aspect, the sixth aspect, and any one of the possible implementation manners.

A tenth aspect provides an encoding end device, wherein the encoding end device comprises: one or more processors, a memory, and a communication interface. The memory, communication interface is coupled to one or more processors; the memory is for storing computer program code, the computer program code comprising instructions, and when the one or more processors execute the instructions, the encoding end device performs the eighth aspect as described above An encoding method of image data as described in any of the possible implementations.

In an eleventh aspect, a computer readable storage medium is provided, wherein the computer readable storage medium stores instructions, wherein when the instructions are run on a decoding end device, the decoding end device is configured to perform The method for decoding image data according to the first aspect, the third aspect, the fourth aspect, the sixth aspect, and any one of the possible implementation manners.

According to a twelfth aspect, a computer readable storage medium is provided, wherein the computer readable storage medium stores instructions, wherein when the instructions are run on an encoding device, the encoding device is configured to perform The encoding method of the image data described in the above eighth aspect and any one of the possible implementation manners.

A thirteenth aspect, a computer program product comprising instructions for causing a decoding end device to perform the first aspect, the third aspect, the fourth aspect, and the sixth aspect as described above when the computer program product is run on the decoding end device And a decoding method of the image data as described in any of the possible implementations.

A fourteenth aspect, a computer program product comprising instructions for causing an encoding end device to perform the apparatus as described in the eighth aspect above and any one of the possible implementations as described above, when the computer program product is run on the encoding end device The encoding method of image data.

In the present application, the names of the above-mentioned decoding end device and the encoding end device are not limited to the device or the functional module itself. In actual implementation, these devices or functional modules may appear under other names. As long as the functions of the respective devices or functional modules are similar to the present application, they are within the scope of the claims and their equivalents.

These and other aspects of the present application will be more apparent from the following description.

DRAWINGS

FIG. 1 is a schematic structural diagram of different division manners provided by an embodiment of the present application;

2 is a schematic structural diagram of a quadtree hierarchy according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a combined division of a quadtree partition and a binary tree partition according to an embodiment of the present disclosure;

4 is a schematic structural diagram of an image processing system according to an embodiment of the present application;

FIG. 5 is a schematic structural diagram of hardware of a mobile phone according to an embodiment of the present application;

FIG. 6 is a schematic flowchart 1 of a method for decoding image data according to an embodiment of the present application;

FIG. 7 is a second schematic flowchart of a method for decoding image data according to an embodiment of the present disclosure;

FIG. 8 is a schematic flowchart 3 of a method for decoding image data according to an embodiment of the present disclosure;

FIG. 9 is a schematic flowchart of a method for encoding image data according to an embodiment of the present application;

FIG. 10 is a schematic structural diagram of a decoding end device according to an embodiment of the present disclosure;

FIG. 11 is a schematic structural diagram of an apparatus of an encoding end according to an embodiment of the present disclosure.

Detailed ways

The terms "first", "second", "third", and "fourth" and the like in the specification and claims of the present application and the above drawings are used to distinguish different objects, and are not intended to limit the specific order.

In the embodiments of the present application, the words "exemplary" or "such as" are used to mean an example, illustration, or illustration. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of the words "exemplary" or "such as" is intended to present the concepts in a particular manner.

In order to facilitate the understanding of the embodiments of the present application, the related elements involved in the embodiments of the present application are first introduced herein.

Coding Tree Unit (CTU): An image consists of multiple CTUs. One CTU usually corresponds to a square image area. As shown in Figure 1(a), image 10 consists of multiple CTUs (including CTU A). , CTU B, CTU C, etc.). The coding information corresponding to a certain CTU includes luminance values and/or chrominance values of pixels in a square image region corresponding to the CTU. Furthermore, the coding information corresponding to a certain CTU may further include syntax elements indicating how to divide the CTU into at least one CU, and a method of decoding each CU to obtain a reconstructed image.

An image area corresponding to one CTU may include 64×64, 128×128, or 256×256 pixels. In one example, a CTU of 64x64 pixels contains a rectangular pixel lattice of 64 columns of 64 pixels per column, each pixel containing a luminance component and/or a chrominance component.

It can be understood that the CTU can also correspond to a rectangular image area or an image area of other shapes. The image area corresponding to one CTU may also be an image area in which the number of pixels in the horizontal direction is different from the number of pixels in the vertical direction, for example, including 64 × 128 pixels.

Coding Unit (CU): generally corresponds to a rectangular area of A×B, A is the width of the rectangle, and B is the height of the rectangle. The width referred to in the embodiment of the present application refers to the width shown in FIG. 1 . The length in the X-axis direction (horizontal direction) in the two-dimensional Cartesian coordinate system XoY, the height refers to the length in the Y-axis direction (vertical direction) in the two-dimensional Cartesian coordinate system XoY shown in FIG. Here, the values of A and B may be the same or different. The values of A and B are usually an integer power of 2, for example: 256, 128, 64, 32, 16, 8, or 4. A CU can obtain a reconstructed image block of an A×B rectangular region by decoding processing, and the decoding process usually includes processing such as prediction, dequantization, and inverse transform to generate a predicted image and a residual. The reconstructed image block is obtained by superimposing the predicted image and the residual. A plurality of reconstructed image blocks can be used to obtain a final reconstructed image.

Quad-Tree (QT): A tree structure in which one node can be divided into four sub-nodes. In one example, the video codec standard H.265 adopts a quadtree-based CTU partitioning method: a CTU is used as a root node, and each node corresponds to a square image area; for a node, the node can no longer be divided ( At this time, the square image area corresponding to the node is a CU), and the node may be divided into four lower level nodes, that is, the square image area corresponding to the node is divided into four square areas of the same size (the width thereof) The height is half of the width and height of the front area, and each area corresponds to one node. As shown in Figure 1(b), CTU A is the root node, and CTU A is divided into four nodes a, b, c, and d. If the node a is not divided, the square image area corresponding to node a corresponds to one CU.

Binary Tree (BT): A tree structure in which a node can be divided into two sub-nodes. For a node on the binary tree structure, the node may not be divided, or the node may be divided into two nodes of the next level. The binary tree division method can include:

(1), horizontal two points

The image area corresponding to the node is divided into upper and lower areas of the same size, that is, the width of the divided image area remains unchanged, and the height becomes half of the divided image area, and each divided image area corresponds to A child node. As shown in FIG. 1(c), the node b is divided by a horizontal binary division method to generate a node e and a node f.

(2), vertical two points

The area corresponding to the node is divided into left and right areas of the same size, that is, the height of the divided image area remains unchanged, the width becomes half of the divided image area, and each divided image area corresponds to one Child node. As shown in Fig. 1(d), the node d is divided by a vertical binary division method to generate a node g and a node h.

It can be understood that the above horizontal dichotomy and vertical dichotomy are an example of the manner in which the binary tree is divided. The image area corresponding to the node may be divided into two sub-areas in another manner. For example, two high unequal sub-regions are horizontally divided, or vertically divided into two unequal regions.

Triple Tree (TT): A tree structure in which one node can be divided into three child nodes. For a node on the tri-tree structure, the node may not be divided, or the node may be divided into three lower-level nodes. The trigeminal division can include:

(1), horizontal three points

The image area corresponding to the node is divided into upper, middle and lower regions, and each region corresponds to one child node. In one example, the heights of the upper, middle, and lower regions are respectively 1/4, 1/2, and 1/4 of the height of the image region before division. As shown in FIG. 1(e), the node c is divided by a horizontal three-division method to generate a node j, a node k, and a node m. The height of the image region corresponding to the node j is the height 1/4 of the image region corresponding to the node c. The height of the image area corresponding to the node k is 1/2 of the height of the image area corresponding to the node c, and the height of the image area corresponding to the node m is 1/4 of the height of the image area corresponding to the node c. In another example, the heights of the upper, middle, and lower regions are respectively 1/3, 1/3, and 1/3 of the height of the image region before the division, that is, the image region corresponding to the node is as shown in FIG. The direction of the X-axis in the two-dimensional Cartesian coordinate system XoY is equally divided into three regions. As shown in Fig. 1(f), the node c is divided by a horizontal three-division method to generate a node j, a node k, and a node m. The height of the image region corresponding to the node j and the height of the image region corresponding to the node k correspond to the node m. The height of the image area is 1/3 of the height of the image area corresponding to the node c.

(2), vertical three points

The image area corresponding to the node is divided into three areas of left, middle and right, each area corresponding to one child node. In one example, the widths of the left, middle, and right image regions are respectively 1/4, 1/2, and 1/4 of the width of the image region before division. As shown in Fig. 1(g), the node c is divided by a vertical three-division method to generate a node p, a node q, and a node x. The width of the image region corresponding to the node p is the width of the image region corresponding to the node c. 4. The width of the image area corresponding to the node q is 1/2 of the width of the image area corresponding to the node c, and the width of the image area corresponding to the node x is 1/4 of the width of the image area corresponding to the node c. In another example, the heights of the left, middle, and right image regions are respectively 1/3, 1/3, and 1/3 of the height of the image region before the division, that is, the image region corresponding to the node is shown in FIG. The direction of the X-axis in the two-dimensional Cartesian coordinate system XoY is equally divided into three regions. As shown in FIG. 1(h), the node c is divided by a vertical three-division method to generate a node p, a node q, and a node x, the width of the image region corresponding to the node p, the width of the image region corresponding to the node q, and the node x. The width of the corresponding image area is 1/3 of the width of the image area corresponding to the node c.

Image encoding: The process of compressing a sequence of images into a stream of code.

Image decoding: The process of restoring a code stream into a reconstructed image according to specific grammar rules and processing methods.

The video codec standard H.265 uses the QT partitioning method to divide the CTU. Specifically, the CTU is used as the root node (root) of the QT structure, and the CTU is recursively divided into a plurality of leaf nodes according to the QT division manner. If a node is no longer split, the node is called a leaf node. As can be seen from the above description, an image is composed of a plurality of CTUs, and one CTU corresponds to one square image area, that is, one CTU corresponds to one image block. Each leaf node corresponds to one CU, and each CU is equivalent to a certain sub-image block in the image block corresponding to the CTU, and the sub-image block can no longer be divided by using the QT division manner. If it is necessary to continue to divide a certain node, the image area corresponding to the node is divided into four image areas of the same size. Referring to FIG. 1(b), after the image area corresponding to the node is divided, each generated after the division is generated. Each image area corresponds to a node, and it is also necessary to determine whether these nodes will continue to be divided. Whether a node is divided is indicated by a partition flag bit (such as split_cu_flag) corresponding to the node in the code stream. The level of the root node in the QT structure (referred to as the QT level) is 0, and the QT level of the child node generated by the QT partitioning method is 1 for the QT level of the parent node of the child node.

Exemplarily, the split flag bit of a certain node is represented by split_cu_flag, split_cu_flag=0 indicates that the node is no longer divided, and split_cu_flag=1 indicates that the node is continuously divided. As shown in FIG. 2, in the case where the value of split_cu_flag of a 64×64 CTU node (QT level is 0) is 1, the CTU node is divided into four 32×32 nodes (QT level is 1), and the fourth The 32×32 nodes are node A1, node A2, node A3, and node A4, respectively. Each of the four 32×32 nodes can be further divided or not divided according to its corresponding split_cu_flag. If the value of the split_cu_flag of the node A1 is 1, the node A1 is further divided, and the node A1 is divided into four 16×16 nodes (the QT level is 2), and the four 16×16 nodes are the node B1 and the node B2, respectively. , node B3, and node B4. And so on, until all nodes are no longer divided, so that a CTU is divided into a group of CUs. In the same QT structure, the minimum size of each CU (ie, the minimum size of the CU) is the same, and the minimum size of the CU is identified in the Sequence Parameter Set (SPS) of the code stream, for example, 8×8. The CU is the smallest CU. In the above recursive partitioning process, if the size of a certain node is equal to the minimum CU size, it is determined that the node is no longer divided, and it is not necessary to include the division flag bit of the node in the code stream.

The division manner in which the CTU is divided into a group of CUs corresponds to one coding tree, and FIG. 3(a) is an example of a coding tree. A coding tree may correspond to only one division, such as a quadtree; or it may correspond to multiple divisions, such as the aforementioned QTBT structure and the QT-BT/TT structure described below.

The first level coding tree, the second level coding tree, the third level coding tree, ..., the Nth coding tree respectively correspond to a set of different division modes, and N is a positive integer greater than 3. The set of different division manners may be a type of a certain tree, such as a trigeminal tree, a binary tree, or a quadtree; or a collection of division manners in the same tree type, such as horizontal dichotomy, vertical dichotomy, etc.; It can also be a combination of the two. It can be understood that a coding tree does not need to include multiple different levels of coding trees at the same time. For example, a coding tree may only include a first-level coding tree; or a coding tree may include first-level and second-level coding trees; or a coding tree may include a first-level coding tree, a second-level coding tree, and a A three-level coding tree.

In one example, the first level coding tree may include a quadtree partition, and the second level coding tree may include a binary tree partition and a triblock tree partition.

In another example, the first level coding tree may include quadtree partitioning, and the second level coding tree may include binary tree partitioning, triblock tree partitioning, and quadtree partitioning.

In another example, the first level coding tree may include quadtree partitioning and binary tree partitioning, and the second level coding tree includes triblock tree partitioning.

In another example, the first level coding tree may comprise a quadtree partition, the second level coding tree may comprise a binary tree partition, and the third level coding tree may comprise a triblock tree partition.

In another example, the first level coding tree may include a horizontal binary, the second level coding tree may include vertical binary and quadtree partitioning, and the third level coding tree may include vertical three and horizontal three.

The second level coding tree may also include other division manners, which is not specifically limited in this embodiment of the present application.

The coding end device usually adopts Rate Distortion Optimization (RDO) technology to determine which coding tree coding is used by the CTU. Specifically, for each node, the encoding end device calculates a Rate Distortion Cost (RD cost) for each of the partitioning modes that the node can use, compares the calculated RD cost, and corresponds to the minimum RD cost. The division method is determined as the division mode of the node.

Similar to the QT structure, the level of a node in the BT structure is called the BT level, and the BT level of the child node generated by the BT partitioning method is 1 for the BT level of the parent node of the child node. If the BT level of a node is equal to the maximum BT level, it is determined that the node is no longer divided. In general, the largest BT level in the BT structure is identified in the SPS.

In an example, the BT division mode is introduced on the basis of the QT division mode, wherein the QT division manner and the BT division manner are cascaded, and the division manner is called a QTBT division manner. Specifically, the CTU is divided according to the QT division manner, and the leaf nodes of the QT can continue to be divided by the BT division manner, that is, the first-level coding tree is QT, and the second-level coding tree is BT.

As shown in Fig. 3(a), each endpoint represents a node, the solid line indicates that the node is divided by QT division, the dotted line indicates that the node is divided by BT division, and A to M are 13 leaf nodes, and each leaf node corresponds to 1 CU. In the BT structure, 10 represents a vertical dichotomy and 11 represents a horizontal dichotomy. Fig. 3(b) shows an image area corresponding to the CTU divided according to the division manner shown in Fig. 3(a).

In the QTBT division mode, each CU has a QT level and a BT level. For a certain CU in the QTBT partitioning mode, the QT level of the CU is the QT level of the QT leaf node to which the CU belongs, and the BT level of the CU is the BT level of the BT leaf node to which the CU belongs. If the CTU is not divided, that is, there is only one CU, the QT level of the CU is 0, and the BT level is 0.

Exemplarily, in FIG. 3(a), the QT level of A and B is 1, and the BT level is 2; the QT level of C, D, and E is 1, and the BT level is 1; the QT level of F, K, and L is 2, the BT level is 1; the QT level of I and J is 2, the BT level is 0; the QT level of G and H is 2, the BT level is 2; the QT level of M is 1, and the BT level is 0.

In the QTBT division mode, the CU shape is more diverse and can better adapt to the content of the partial image. All CUs generated by the QT partitioning method in the H.265 standard can only be square, that is, the width of the CU is equal to the height of the CU. After the BT partitioning mode is introduced based on the QT partitioning mode, the width and height of the CU may be different. For example, the aspect ratio (the value is equal to the width divided by the height) is 2, 4, 8, 16, 1/2, 1/4. 1/8 or 1/16. Of course, in the QTBT division mode, the width and height of all CUs cannot be smaller than the side length of the minimum CU (for example, the minimum CU can be set to 4×4). In general, the SPS of a video stream contains the size information of the smallest CU.

On the basis of the above QTBT, a QT-BT/TT division mode may also be included, that is, nodes in the first-level coding tree use QT division mode, and nodes in the second-level coding tree may use BT division mode or TT division. the way. Specifically, the CTU is a root node of the first-level coding tree, and the CTU is divided into QT division manners to generate a plurality of leaf nodes of the first-level coding tree; and the leaf node of the first-level coding tree is used as the second-level coding tree. The root node divides the nodes in the second-level coding tree by BT partitioning (including horizontal binary and vertical binary) or TT partitioning (including horizontal three-point and vertical three-point) to generate several second-level coding trees. Leaf node.

However, for each node, the encoding end device usually needs to calculate the RD cost of each partitioning mode that the node can use, compare the calculated RD cost, and determine the partitioning mode corresponding to the minimum RD cost as the node's The way of division. In the QT-BT/TT division mode, since the nodes in the second-level coding tree can use the BT division mode, the TT division mode can also be used. Therefore, for each node in the second-level coding tree, the coding end devices are used. It is necessary to calculate the RD cost of the four division methods (horizontal, vertical, horizontal, and vertical) to determine the actual division of each node in the second-level coding tree. The coding complexity is high.

For the above problem, the embodiment of the present application provides a method for decoding image data. After obtaining a code stream including image data, the decoding end device obtains information about node partitioning manner of the first-level coding tree and second by analyzing the code stream. The node division mode information of the level coding tree, if the node division mode information of the second level coding tree indicates that the division manner corresponding to the first node in the second level coding tree is a trinomial division, the decoding end device obtains the parsing code stream to obtain The coding information of the three sub-nodes of the first node, one sub-node of the first node corresponds to one coding unit CU, so that the decoding end device can decode and reconstruct the coding unit according to the coding information of the three sub-nodes of the first node, An image corresponding to the image data is obtained. In this application, the root node of the first-level coding tree corresponds to one CTU, and the leaf node of the first-level coding tree is performed by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree. Instructed, the root node of the second level coding tree is a leaf node of the first level coding tree. The decoding end device in the embodiment of the present application only needs to determine that the partitioning manner corresponding to the first node is a tri-tree partition, and the encoding information of the three child nodes of the first node can be directly obtained, and the three child nodes of the first node need not be sequentially performed. Decoding is performed to speed up the decoding and reduce the complexity of decoding.

Correspondingly, the embodiment of the present application further provides an encoding method of image data, after the encoding end device determines the CTU corresponding to the image block to be encoded, the CTU is divided according to the node division manner corresponding to the first-level coding tree, a leaf node of the first level coding tree, wherein a root node of the first level coding tree corresponds to a CTU; the coding end device determines, according to a preset condition, a division manner that the first node in the second level coding tree can use, and second The root node of the level coding tree is a leaf node of the first level coding tree. The preset condition includes: if the division method corresponding to the parent node of the first node is a trinomial division, it is determined that the first node is not divided; if the first node can The coding mode used is not divided, and the coding end device encodes the coding unit corresponding to the first node to obtain a coding unit code stream corresponding to the coding unit. The preset condition in the embodiment of the present application limits the division of nodes in the second-level coding tree, and the corresponding division manner of a node in the second-level coding tree is a tri-tree division, and the child nodes of the node are no longer Continue to divide, thus greatly reducing the complexity of dividing the nodes in the second-level coding tree and reducing the coding complexity.

The embodiments of the present application provide a method for encoding and decoding image data, which is applicable to an image processing system. FIG. 4 is a schematic structural diagram of an image processing system according to an embodiment of the present application. As shown in FIG. 4, the image processing system includes an encoding end device 40 and a decoding end device 41. The encoding end device 40 and the decoding end device 41 may be independently configured or integrated in the same device, which is not specifically limited in this embodiment of the present application. In FIG. 1, the encoding end device 40 and the decoding end device 41 are independently set as an example. For the convenience of description, the following description will be made by taking the independent setting of the encoding end device and the decoding end device as an example.

Specifically, after capturing a certain image, the encoding end device 40 processes the CTU corresponding to each image in the image according to the division manner of the first-level coding tree and the division manner of the second-level coding tree, where If the partitioning mode of a node in the second-level coding tree is a tri-tree partition, the child nodes of the node are no longer divided. After the partitioning is completed, the encoding end device 40 acquires the CTU code stream, and sends the CTU code stream to the decoding end device 41. The CTU code stream is sent; the decoding end device 41 parses the acquired CTU code stream according to the split information of the node, and acquires a reconstructed image.

Both the encoding end device 40 and the decoding end device 41 may be various devices configured with a camera (such as a front camera or a rear camera), for example, the encoding end device and the decoding end device are wearable electronic devices (such as smart watches, etc.) ), Polaroid, can also be the mobile phone shown in Figure 5, but also can be a tablet, desktop computer, virtual reality device, laptop, ultra-mobile personal computer (UMPC), personal digital assistant ( Personal Digital Assistant (PDA), etc., the specific form of the encoding end device 40 and the decoding end device 41 is not particularly limited in the embodiment of the present application.

With reference to FIG. 4, as shown in FIG. 5, both the encoding end device 40 and the decoding end device 41 in this embodiment may be mobile phones. The embodiment will be specifically described below by taking a mobile phone as an example.

It should be understood that the illustrated mobile phone is only one example of the encoding end device 40 and the decoding end device 41, and the mobile phone may have more or fewer components than those shown in the figure, and two or more may be combined. Parts, or can have different part configurations. The various components shown in FIG. 5 may be implemented in hardware, software, or a combination of hardware and software, including one or more signal processing and/or application specific integrated circuits.

As shown in FIG. 5, the mobile phone includes an RF (Radio Frequency) circuit 50, a memory 51, an input unit 52, a display unit 53, a sensor 54, an audio circuit 55, and a Wireless Fidelity (Wi-Fi) module 56. The processor 57, the Bluetooth module 58, and the power source 59 and the like. It will be understood by those skilled in the art that the structure of the handset shown in FIG. 5 does not constitute a limitation to the handset, and may include more or less components than those illustrated, or some components may be combined, or different components may be arranged.

The following describes the components of the mobile phone in detail with reference to FIG. 5:

The RF circuit 50 can be used for transmitting and receiving information or during a call, and receiving and transmitting signals. The downlink information of the base station can be received and processed by the processor 57. In addition, the data related to the uplink is sent to the base station. Typically, RF circuitry includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and the like. In addition, RF circuitry 50 can also communicate with the network and other mobile devices via wireless communication. The wireless communication can use any communication standard or protocol, including but not limited to global mobile communication systems, general packet radio services, code division multiple access, wideband code division multiple access, long term evolution, email, short message service, and the like.

The memory 51 can be used to store software programs and data. The processor 57 executes various functions and data processing of the mobile phone by running software programs and data stored in the memory 51. The memory 51 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application required for at least one function (such as a sound playing function, an image playing function, etc.), and the like; the storage data area may be stored according to Data created by the use of the mobile phone (such as audio data, phone book, video, etc.). Further, the memory 51 may include a high speed random access memory, and may also include a nonvolatile memory such as at least one magnetic disk storage device, flash memory device, or other volatile solid state storage device. In the following embodiments, the memory 51 stores an operating system that enables the mobile phone to operate, such as developed by Apple.

Operating system, developed by Google Inc.

Open source operating system, developed by Microsoft Corporation

Operating system, etc.

An input unit 52, such as a touch screen, can be used to receive input numeric or character information and to generate signal inputs related to user settings and function controls of the handset. Specifically, the input unit 52 can include a touch screen 521 and other input devices 522. The touch screen 521, also referred to as a touch panel, can collect touch operations on or near the user (eg, the user operates on the touch screen 521 or near the touch screen 521 using any suitable object or accessory such as a finger, a stylus, or the like. ), and drive the corresponding connection device according to a preset program. Alternatively, the touch screen 521 may include two parts (not shown in FIG. 5) of the touch detecting device and the touch controller. Wherein, the touch detection device detects the touch orientation of the user, and detects a signal brought by the touch operation, and transmits the signal to the touch controller; the touch controller receives the touch information from the touch detection device, converts the touch information into contact coordinates, and sends the touch information. The processor 57 is provided and can receive instructions from the processor 57 and execute them. In addition, the touch screen 521 can be implemented in various types such as resistive, capacitive, infrared, and surface acoustic waves.

The display unit 53 (ie, the display screen) can be used to display information input by the user or information provided to the user and a graphical user interface (GUI) of various menus of the mobile phone. The display unit 53 may include a display panel 531 disposed on the front of the mobile phone. Optionally, the display panel 531 can be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), or the like. Further, the touch screen 521 can cover the display panel 531. When the touch screen 521 detects a touch operation on or near it, the touch screen 521 transmits to the processor 57 to determine the type of the touch event, and then the processor 57 displays the panel according to the type of the touch event. A corresponding visual output is provided on the 531. Although, in FIG. 5, the touch screen 521 and the display panel 531 are two independent components to implement the input and output functions of the mobile phone, in some embodiments, the touch screen 521 and the display panel 531 may be integrated to implement the mobile phone. Input and output functions.

In other embodiments, the touch screen 521 can also be provided with a pressure sensing sensor, so that when the user performs a touch operation on the touch panel, the touch panel can also detect the pressure of the touch operation, and the mobile phone can be more accurate. The touch operation is detected.

The handset may also include at least one type of sensor 54, such as a light sensor, motion sensor, and other sensors. Specifically, the light sensor may include an ambient light sensor and a proximity sensor, and the ambient light sensor may adjust the brightness of the display panel 531 according to the brightness of the ambient light, and the proximity light sensor is disposed on the front side of the mobile phone, when the mobile phone moves to the ear, according to Close to the detection of the light sensor, the mobile phone turns off the power of the display panel 531, so that the mobile phone can further save power. As a kind of motion sensor, the accelerometer sensor can detect the acceleration of each direction (usually three axes). When it is still, it can detect the magnitude and direction of gravity. It can be used to identify the gesture of the mobile phone (such as horizontal and vertical screen conversion, related Game, magnetometer attitude calibration), vibration recognition related functions (such as pedometer, tapping). Other sensors such as gyroscopes, barometers, hygrometers, thermometers, and infrared sensors that can be configured on the mobile phone are not described here.

An audio circuit 55, a speaker 551, and a microphone 552 provide an audio interface between the user and the handset. The audio circuit 55 can transmit the converted electrical data of the received audio data to the speaker 551, and is converted into a sound signal output by the speaker 551. On the other hand, the microphone 552 converts the collected sound signal into an electrical signal, and the audio circuit 55 is used by the audio circuit 55. After receiving, it is converted into audio data, and then the audio data is output to the RF circuit 50 for transmission to, for example, another mobile phone, or the audio data is output to the memory 51 for further processing.

Wi-Fi is a short-range wireless transmission technology. The mobile phone can help users to send and receive emails, browse web pages and access streaming media through the Wi-Fi module 56, which provides users with wireless broadband Internet access.

The processor 57 is a control center of the mobile phone, and connects various parts of the entire mobile phone by using various interfaces and lines, and executes various kinds of mobile phones by running or executing a software program stored in the memory 51 and calling data stored in the memory 51. Function and process data to monitor the phone as a whole. In some embodiments, processor 57 may include one or more processing units; processor 57 may also integrate an application processor and a modem processor, where the application processor primarily processes operating systems, user interfaces, applications, etc. The modem processor primarily handles wireless communications. It can be understood that the above modem processor can also be independently set.

The Bluetooth module 58 is configured to exchange information with other devices through a short-range communication protocol such as Bluetooth. For example, the mobile phone can establish a Bluetooth connection through the Bluetooth module 58 and a wearable electronic device (such as a smart watch) that also has a Bluetooth module, thereby performing data interaction.

The handset also includes a power source 59 (such as a battery) that powers the various components. The power supply can be logically coupled to the processor 57 through the power management system to manage functions such as charging, discharging, and power consumption through the power management system.

Hereinafter, a method for encoding and decoding image data provided by an embodiment of the present application will be described in detail in conjunction with specific embodiments.

FIG. 6 is a schematic flowchart diagram of a method for decoding image data according to an embodiment of the present application, and the decoding method can be applied to the image processing system shown in FIG. 4.

As shown in FIG. 6, the decoding method of the image data includes:

S600. The decoding end device obtains a code stream that includes image data.

Optionally, the code stream that includes the image data obtained by the decoding device includes a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), a slice header, or a slice header ( A slice segment header), and a CTU code stream, the CTU code stream carries image data.

S601. The decoding end device decodes the obtained code stream to obtain node division manner information of the first-level coding tree.

The root node of the first-level coding tree corresponds to a CTU, and the leaf node of the first-level coding tree is indicated by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree. The node division manner corresponding to the first-level coding tree includes quadtree partitioning.

After obtaining the code stream, the decoding end device parses the CTU code stream in the code stream to obtain node partitioning information of the first level coding tree.

Optionally, the method for the decoding end device to parse the CTU code stream to obtain the node partitioning information of the first level coding tree may be: the decoding end device uses the CTU as the root node of the first level coding tree, parses the CTU code stream, and obtains the CTU. The first identifier (such as SplitFlag) included in the syntax element of the code stream is used to indicate how to divide the CTU into at least one CU, that is, the first identifier indicates node division manner information of the first-level coding tree. In an example, if the value of a SplitFlag is 0, the node corresponding to the SplitFlag is a leaf node of the first-level coding tree; if the value of a SplitFlag is 1, the node corresponding to the SplitFlag is continuously obtained. SplitFlag of the four child nodes until the information of all leaf nodes of the first level coding tree is determined.

It should be noted that, if the width of the image region corresponding to a certain node is equal to the first threshold (for example, the first threshold is 8 or 16), the node is a leaf node of the first-level coding tree, and the SplitFlag corresponding to the node is The value is 0.

Optionally, the method for the decoding end device to parse the CTU code stream to obtain the node partitioning information of the first level coding tree may also be: the decoding end device uses the CTU as the root node of the first level coding tree, parses the CTU code stream, and obtains the a second identifier (such as NSFlag) included in the syntax element of the CTU code stream for indicating whether to divide the node of the first level coding tree; if the value of the second identifier is the first value (for example, 1), The node corresponding to the second identifier is a leaf node of the first-level coding tree, and is also a second-level coding leaf node; if the value of the second identifier is a second value (for example, 0), acquiring the third identifier included in the syntax element (such as QTSplitFlag); if the value of the third identifier is a third value (for example, 0), it indicates that the node corresponding to the third identifier is a first-level encoded leaf node, but not a leaf node of the second-level coding tree; If the value of the third identifier is a fourth value (for example, 1), the second identifier of the four child nodes of the node corresponding to the third identifier is continuously obtained until the information of all the leaf nodes of the first level coding tree is determined.

It should be noted that, if the width of the image region corresponding to a certain node is equal to the first threshold (for example, the first threshold is 8 or 16), the node is a leaf node of the first-level coding tree, and the third node corresponding to the node The value of the identification is the third value. In addition, if the width or height of the image area corresponding to a certain node is greater than the second threshold, and the value of the second identifier corresponding to the node is the second value, the value of the third identifier is the third value. If the mapping mode of the node is QT, the value of the second identifier corresponding to the node is the second value, and the value of the third identifier corresponding to the node is the third value.

S602. The decoding end device parses the obtained code stream to obtain node division mode information of the second-level coding tree.

The root node of the second-level coding tree is a leaf node of the first-level coding tree. The node division manner corresponding to the second-level coding tree is different from the node division manner corresponding to the first-level coding tree. In this embodiment, the node division manner corresponding to the second-level coding tree includes binary tree division and tri-tree division.

After obtaining the node partitioning mode information of the first-level coding tree, the decoding end device performs the first-level coding tree indicating the node partitioning manner corresponding to the node partitioning mode information of the first-level coding tree and the root node of the first-level coding tree. The leaf node is used as the root node of the second-level coding tree, and the CTU code stream is parsed to obtain the division mode information of the nodes of the second-level coding tree.

Optionally, the method for the decoding end device to parse the CTU code stream to obtain the partitioning mode information of the node of the second level coding tree may be: the decoding end device parses the CTU code stream, and obtains a method for indicating how to divide the second level coding tree. The fourth identifier of a node (such as STSplitMode), that is, the fourth identifier indicates the node division manner information of the second-level coding tree.

If a fourth identifier indicates no division (eg, STSplitMode=0), it indicates that the node corresponding to the fourth identifier is a leaf node of the second-level coding tree.

If a fourth identifier indicates a tri-tree partition (such as STSplitMode=3 or 4), it indicates that the node corresponding to the fourth identifier has three child nodes, and each of the three child nodes is a second-level code. Leaf node.

If a fourth identifier indicates a binary tree partition (such as STSplitMode=1 or 2), it indicates that the node corresponding to the fourth identifier has two child nodes, and the encoding end device continues to acquire two child nodes of the node corresponding to the fourth identifier. The fourth identifier is determined until information about all leaf nodes of the second level coding tree is determined.

It can be seen from the above description that for a certain CU in the QTBT partitioning mode, the QT level of the CU is the QT level of the QT leaf node to which the CU belongs, and the BT level of the CU is the BT level of the BT leaf node to which the CU belongs. That is, the second level coding tree level represents the level of a node relative to the root node of the second level coding tree in which the node is located. The second level coding tree level of the root node of the second level coding tree is 0. If a node of the second level coding tree is divided, the second level coding tree level of the child node of the node is the second of the node. Level coding tree level plus 1.

Optionally, the division manner corresponding to the second-level coding tree in this embodiment may further include other division manners except the binary tree division and the tri-tree division, which are not specifically limited in this embodiment of the present application.

Exemplarily, the division manner corresponding to the second-level coding tree in the embodiment further includes a quad-tree division; when the second-level coding tree level of a node is greater than the preset level and the height and width of the image region corresponding to the node When the ratio (the height of the image region corresponding to the node divided by the width of the image region corresponding to the node) is less than or equal to the third threshold, the division manner corresponding to the node further includes quadtree partitioning. In one example, STSplitMode=5 indicates that the partitioning mode corresponding to the node is quadtree partitioning.

Optionally, the method for the decoding end device to parse the CTU code stream to obtain the partitioning mode information of the node of the second level coding tree may further be: the decoding end device determines that the first information of a node of the second level coding tree satisfies certain conditions. , indicating that the node is a leaf node of the second-level coding tree. Here, the first information of the node refers to at least one of a width of an image area corresponding to the node, a height of an image area corresponding to the node, and a second level coding tree level of the node. In this case, the CTU code stream may not carry the fourth identifier corresponding to the node.

Exemplarily, if a node of the second-level coding tree meets any of the following conditions, the node is a leaf node of the second-level coding tree:

(1) The second level coding tree level of a node is equal to the preset maximum second level coding tree level (for example, the preset maximum second level coding tree level is 3, 4 or 2).

(2) The height and width of the image area corresponding to a certain node are equal to the height and width of the preset minimum CU.

(3) The height (or width) of the image area corresponding to a certain node is greater than the height (or width) of the preset maximum CU.

(4) The aspect ratio (or aspect ratio) of the image area corresponding to a certain node is greater than or equal to the preset ratio.

(5) The image area corresponding to a certain node includes a pixel value that is less than or equal to a preset pixel value.

Of course, the above conditions (1) to (5) are merely examples of the conditions for determining that a certain node is a leaf node of the second-level coding tree, and this condition is not limited.

Optionally, the encoding end device may obtain the preset maximum second level coding tree level, the preset minimum CU height (or width) from the SPS, the PPS, or the strip header in the code stream that includes the image data, The preset maximum CU height (or width), preset ratio, preset pixel value, of course, the preset maximum second-level coding tree level, the preset minimum CU height (or width), preset The height (or width) of the maximum CU, the preset ratio, and the preset pixel value may also be preset by the image processing system.

It can be seen from the above description that the fourth identifier in the embodiment of the present application is used to indicate how to divide a node in the second level coding tree. Optionally, the fourth identifier may include a node division identifier for indicating whether to continue to divide the node, a division direction identifier for indicating which direction to divide the node, and a division mode for indicating which manner the node is divided according to which manner Logo.

Exemplarily, the node division identifier is STSplitFlag. If the value of STSplitFlag is equal to 0, it indicates that the node corresponding to the STSplitFlag is not divided. If the value of STSplitFlag is equal to 1, it indicates that the node corresponding to the STSplitFlag is continued to be divided. The division direction identifier is STSplitDir. If the value of STSplitDir is equal to 0, it indicates that the node corresponding to the STSplitDir is divided according to the horizontal direction; if the value of STSplitDir is equal to 1, it indicates that the node divides the node corresponding to the STSplitDir in the vertical direction. The division mode identifier is STSplitType. If the value of the STSplitType is equal to 0, the division method corresponding to the node corresponding to the STSplitType is a binary tree division; if the value of the STSplitDir is equal to 1, the division corresponding to the node corresponding to the STSplitType is trifurcation. Tree division.

Optionally, the fourth identifier in the embodiment of the present application may further include a binary tree partition identifier that is used to indicate whether the node corresponding to the fourth identifier is divided according to a binary tree partitioning manner, and is used to indicate whether the fourth partition is divided according to a tri-tree partition manner. The tri-tree partition identifier and the division direction identifier of the corresponding node are identified (the division direction identifier is the same as the division direction identifier in the previous example).

Exemplarily, the binary tree partitioning identifier is BTFlag. If the value of the BTFlag is equal to 0, the mapping manner corresponding to the node corresponding to the fourth identifier is not the BT partition. If the value of the BTFlag is equal to 1, it indicates that the node corresponding to the fourth identifier corresponds to The division method is BT division. The tribtree partition identifier is TTFlag. If the value of the TTFlag is equal to 0, the partitioning mode corresponding to the node corresponding to the fourth identifier is not the TT partition. If the value of the TTFlag is equal to 1, the partition corresponding to the node corresponding to the fourth identifier is TT division.

Of course, the fourth identifier in the embodiment of the present application may also include any combination of the foregoing node division identifier, the foregoing division direction identifier, and the foregoing division mode identifier, which is not specifically limited in this embodiment of the present application.

It is easy to understand that if the division manner corresponding to the second-level coding tree further includes other division modes other than the binary tree division and the tri-tree division, the fourth identifier may include more identifiers, and details are not described herein again.

Optionally, the decoding device in the embodiment of the present application may perform S602 after executing S601, or may acquire information about a leaf node of the first-level coding tree for the first time in the process of executing S601. The leaf node of the first level coding tree immediately executes S602 until the last leaf node of the first level coding tree is obtained.

S603. If the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is a tri-tree division, the decoding end device parses the code stream to obtain the coding of the three sub-nodes of the first node. information.

In the embodiment of the present application, if the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is a tri-tree partition, the child node of the first node is the second-level The leaf node of the coding tree. The division manner corresponding to the first node is a tri-tree division, and therefore, the first node corresponds to three child nodes. That is to say, if the division manner corresponding to the first node is a tri-tree division, it is indicated that the three sub-nodes of the first node are all leaf nodes of the second-level coding tree.

Further, if the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is a tri-tree partition, the child node of the first node is encoded as a second-level coding. Based on the leaf node of the tree, the decoding device may further determine the information of the first node in combination with the conditions (1) to (5) of the leaf node described in S602 for describing that the node is the second-level coding tree.

Specifically, if the second level coding tree level of the first node is smaller than the preset maximum second level coding tree level, and the height (or width) of the image area corresponding to the first node is greater than the preset minimum CU height (or Width), and the height (or width) of the image region corresponding to the first node is less than or equal to the height (or width) of the preset maximum CU, and the division manner corresponding to the parent node of the first node is not a tri-tree partition, then decoding The end device acquires the partition mode information corresponding to the first node from the CTU code stream; otherwise, the decoding end device determines that the first node is a leaf node of the second level coding tree.

As can be seen from the above description, nodes that are no longer divided correspond to one CU. Correspondingly, each child node of the first node corresponds to one CU.

Specifically, the decoding end device parses the coding unit syntax structure in the code stream (for example, the coding_unit() syntax structure in H.265, the explanation of the coding_unit() syntax structure is described below, and obtains the coding of each CU. Information, the coding information of each CU includes information such as a prediction mode and a transform coefficient of the CU. Here, the decoding end device acquiring the encoding information of each CU means that the decoding end device obtains the encoding information of each leaf node of the second-level coding tree.

Optionally, the decoding end device in the embodiment of the present application may obtain the information of one leaf node of the second-level coding tree in the process of performing S602, parse the code stream, and obtain the coding information of the leaf node; After the coding information of the leaf node is obtained, the leaf information of the next second-level coding tree is obtained, and the coding information of the leaf node of the next second-level coding tree is obtained, and so on, until the last second-level second-level coding The leaf node of the tree.

In one example, the syntax table of the second level coding tree in the embodiment of the present application is as shown in Table 1. The coding_second_tree() is a grammatical structure of the second-level coding tree, and describes information of a node of the second-level coding tree.

In Table 1, x0 and y0 respectively represent the horizontal coordinate offset and the vertical coordinate offset of the upper left corner of the image region corresponding to the node with respect to the upper left corner of the image region corresponding to the CTU; log2CuWidth and log2CuHeight respectively represent the image region corresponding to the node The base-valued logarithm of width and height; stDepth represents the second-level coding tree hierarchy of the node, qtDepth represents the level of the first-level coded leaf node corresponding to the node on the first-level coding tree; parentMode represents the parent node of the node The way of dividing. "X>>Y" means that X is shifted right by Y bits; "X<<Y" means that X is shifted left by Y bits; ae(v) means that syntax elements are parsed using CABAC.

STSplitMode ranges from 0, 1, 2, 3, and 4. When the value of STSplitMode is 0, the node is a leaf node of the second-level coding tree, and the node corresponds to one CU. At this time, the coding unit information is parsed according to the CU syntax structure coding_unit(). The embodiment of the present application does not limit the manner in which the syntax elements of the coding unit information are organized. When the value of STSplitMode is 1 to 4, the node is divided into 2 or 3 sub-nodes by using horizontal dichotomy, vertical dichotomy, horizontal triad, and vertical three-point respectively, and for each sub-node, an image corresponding to each sub-node is determined. The width, height, coordinates, and second-level coding tree hierarchy of the region, and then parse these child nodes according to coding_second_tree().

In Table 1, when the second-level coding tree level of the node (represented by stDepth) is less than the preset maximum second-level coding tree level maxSTDepth, and the width and height of the image area corresponding to the node are less than or equal to the threshold maxSTSize, and When the width or height of the image area corresponding to the node is greater than the threshold value minCUSize, and the division mode corresponding to the parent node of the node is not tri-tree partitioning, the decoding end device acquires the node division mode information STSplitMode of the second-level coding tree from the code stream; otherwise , STSplitMode does not appear in the code stream, so the value of STSplitMode is set to 0 by default.

Optionally, the input variable of the coding_second_tree() may further include a restriction division manner of the node, and the restriction division manner of the node means that the node cannot be divided according to the division manner. It can be understood that the STSplitMode that the decoding end device resolves cannot be the division manner indicated by the above limitation division manner.

Table 1

In another example, the syntax table of the second level coding tree in the embodiment of the present application is as shown in Table 2. In Table 2, if the partitioning mode of the node is tri-tree partitioning, that is, STSplitMode is 3 or 4, the three child nodes of the node are leaf nodes of the second-level coding tree, and the encoding end device can obtain the three child nodes in turn. Encoding information.

S604. The decoding end device performs decoding and reconstruction on the coding unit according to the coding information of the three child nodes of the first node, to obtain an image corresponding to the image data.

The process of decoding and reconstructing a coding unit includes processing such as prediction, inverse quantization, inverse transform, loop filtering, and the like. Specifically, the process of performing decoding reconstruction for each coding unit includes:

(1) Selecting, according to a prediction mode included in the coding information of the CU, using intra prediction or inter prediction to obtain a prediction pixel of the CU.

(2) If the CU has a transform coefficient, the transform coefficient of the CU is inverse quantized and inverse transformed according to the quantization parameter and the transform mode, and the reconstructed residual of the CU is obtained. If the CU does not have a transform coefficient, the reconstructed residual of the CU is 0, that is, the reconstructed residual value of each pixel in the CU is 0.

(3) Adding the predicted pixel of the CU and the reconstructed residual of the CU, and performing loop filtering processing to obtain a reconstructed image block of the CU.

The encoding end device performs decoding reconstruction on each coding unit according to the above method, and acquires a reconstructed image block of each CU. After acquiring the reconstructed image block of each CU, the encoding end device obtains the final reconstructed image according to all the reconstructed image blocks obtained, that is, obtains an image corresponding to the image data.

The decoding end device in the embodiment of the present application only needs to determine that the partitioning manner corresponding to a certain node is a tri-tree partition, and the encoding information of the child node of the node can be directly obtained, and it is not necessary to sequentially decode all the child nodes of the node. Speed up the decoding and reduce the complexity of decoding.

In the embodiment shown in FIG. 6, if the division mode corresponding to the parent node of a node is a tri-tree division, the node does not continue to divide. This condition limits the division of nodes. Under the condition of this condition, the decoding method provided by the embodiment of the present application speeds up the decoding rate and reduces the complexity of decoding. This condition may be preset for the image processing system, or may be determined according to actual needs, which is not specifically limited in the embodiment of the present application.

Further, on the basis of the embodiment shown in FIG. 6, the decoding end device in the embodiment of the present application may further determine whether to limit the node obtained by the tri-tree to continue dividing after obtaining the code stream containing the image data, and then The image data is further analyzed based on the judgment result.

Specifically, in conjunction with FIG. 6, as shown in FIG. 7, the decoding method provided by the embodiment of the present application includes:

S700. The decoding end device obtains a code stream that includes image data.

For the S700, refer to the description of the foregoing S600, and details are not described herein again.

Table 2

S701. The decoding end device parses the obtained code stream to obtain a tri-tree leaf node mode identifier.

The tri-tree leaf node mode identifier is used to indicate whether the node obtained by limiting the tri-tree partitioning continues to divide.

Exemplarily, the tri-tree leaf node mode identifier is represented by tt_leaf_mode_enabled_flag, and the value of tt_leaf_mode_enabled_flag is a first value (for example, 1), and the node after the tri-tree partitioning in the CTU associated with the tt_leaf_mode_enabled_flag is a coded leaf node, that is, if a node corresponds to The division mode is a tri-tree partition, and the child node of the node is a leaf node of the coding tree; the tt_leaf_mode_enabled_flag is a second value (for example, 0), and the node after the tri-tree division in the CTU associated with the tt_leaf_mode_enabled_flag can continue to be divided, that is, if If the partitioning mode of a node is a tri-tree partition, the child nodes of the node may also correspond to other partitioning modes except for the partitioning.

Optionally, at least one of the SPS, the PPS, and the strip header in the code stream including the image data includes the tri-tree leaf node pattern identifier.

Specifically, if both the SPS and the PPS include the tri-tree leaf node pattern identifier, and the value of the tri-tree leaf node pattern identifier included in the SPS is different from the value of the tri-tree leaf node pattern identifier included in the PPS, the tri-tree leaf node pattern identifier included in the PPS is effective. The trigeminal leaf node pattern identifier included in the SPS is invalid. If both the SPS and the strip header include a tri-tree leaf node pattern identifier, and the value of the tri-tree leaf node pattern identifier included in the SPS is different from the value of the tri-tree leaf node pattern identifier included in the strip header, the tri-tree leaf node pattern identifier included in the strip header is valid. The trigeminal leaf node pattern identifier included in the SPS is invalid. If both the PPS and the strip header include the tri-tree leaf node pattern identifier, and the value of the tri-tree leaf node pattern identifier included in the PPS is different from the value of the tri-tree leaf node pattern identifier included in the strip header, the tri-tree leaf node pattern identifier included in the strip header is valid. However, the trigeminal leaf node pattern identifier included in the PPS is invalid. That is, if the trigeminal leaf node pattern identifiers appear simultaneously in the multi-layer syntax structure and the values of the trigeminal leaf node pattern identifiers in the different syntax structures are different, the trigeminal leaf node pattern identifier in the lowermost syntax structure is effective. The trigeminal leaf node pattern identifier in the upper grammatical structure is invalid.

Specifically, after obtaining the code stream containing the image data, the decoding end device parses the code stream, and obtains an effective trigeminal leaf node pattern identifier from the code stream.

Exemplarily, if the SPS includes tt_leaf_mode_enabled_flag, the decoding end device acquires the tt_leaf_mode_enabled_flag corresponding to the CTU from the SPS while decoding the CTU.

S702. The decoding end device decodes the obtained code stream to obtain node division manner information of the first-level coding tree.

S702 can refer to the description of S601 above, and details are not described herein again.

S703. The decoding end device parses the obtained code stream to obtain node division mode information of the second-level coding tree.

S703 can refer to the description of sending S602 above, and details are not described herein again.

S704. If the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is a tri-tree partition, and the tri-tree leaf node pattern identifier indicates that the node obtained by limiting the tri-tree partition continues to be divided. The decoding end device parses the code stream to obtain coding information of the three child nodes of the first node.

S704 is similar to the foregoing S603, except that the decoding end device in S704 needs to determine not only the node division manner information of the second-level coding tree but also the division manner corresponding to the first node in the second-level coding tree. For the tri-tree partitioning, it is also necessary to determine that the tri-tree leaf node mode identifier indicates that the node obtained by limiting the tri-tree partitioning continues to divide.

Exemplarily, Table 3 is a syntax table of the second level coding tree in this embodiment. Compared with Table 1, the parsing condition of STSplitMode in Table 3 is modified to: "The second-level coding tree level stDepth of the node is smaller than the preset maximum second-level coding tree level maxSTDepth, and the width or height of the image area corresponding to the node is greater than the threshold minCUSize And the parent node of the node is not divided by a trinomial partition or tt_leaf_mode_enabled_flag is non-zero.

table 3

S705. The decoding end device performs decoding and reconstruction on the coding unit according to the coding information of the three child nodes of the first node, to obtain an image corresponding to the image data.

S705 can refer to the above S604, and details are not described herein again.

In the embodiment shown in FIG. 6 and FIG. 7 , the division manner corresponding to the first-level coding tree includes a quad-tree division, and the division manner corresponding to the second-level coding tree includes a binary tree division and a tri-tree division. In a practical application, the division manner corresponding to the second-level coding tree may include only the binary tree division, so that the third-level coding tree is extracted, and the division manner corresponding to the third-level coding tree includes the tri-tree division.

As shown in FIG. 8, in this scenario, the method for decoding image data provided by the embodiment of the present application includes:

S800. The decoding end device obtains a code stream that includes image data.

For the S800, refer to the description of the foregoing S600, and details are not described herein again.

S801. The decoding end device decodes the obtained code stream to obtain node division manner information of the first-level coding tree.

S801 can refer to the description of S601 above, and details are not described herein again.

S802. The decoding end device parses the obtained code stream to obtain node division mode information of the second-level coding tree.

The root node of the second-level coding tree is a leaf node of the first-level coding tree. The node division manner corresponding to the second-level coding tree in this embodiment includes a binary tree division.

Similar to the above S602, the decoding end device parses the CTU code stream, and obtains a fourth identifier (such as STSplitMode) for indicating how to divide a node in the second-level coding tree, that is, the fourth identifier indicates the node division of the second-level coding tree. Way information.

In this embodiment, the node division manner corresponding to the second-level coding tree includes a binary tree division. Therefore, the fourth identifier in this embodiment may be used to indicate that a node is not divided, and may also be used to indicate that it corresponds to a node. The division method is horizontal two points or vertical two points.

Exemplarily, the fourth identifier is represented as STSplitMode, and the value of STSplitMode is 0, indicating that the node corresponding to the STSplitMode is not further divided; the value 1 or 2 of the STSplitMode indicates that the corresponding manner of the node corresponding to the STSplitMode is horizontal. Two points or two vertical points.

In conjunction with this example, Table 4 shows a syntax table for the second level coding tree in this embodiment. When the decoding device parses the value of STSplitMode to 0, it starts parsing the third-level coding tree syntax structure; when the value of STSplitMode is 1 or 2, the node is divided into 2 by horizontal dichotomy or vertical dichotomy, respectively. The child nodes are then parsed according to the coding_second_tree() syntax structure for each child node.

Table 4

Optionally, the fourth identifier in this embodiment may include a node partition identifier (such as STSplitFlag) for indicating whether to continue to divide according to a binary tree partition manner, and a split direction identifier (such as STSplitDir) for indicating a direction of the binary tree partition.

Exemplarily, the node division identifier is STSplitFlag. If the value of STSplitFlag is equal to 0, it indicates that the node corresponding to the STSplitFlag is not divided. If the value of STSplitFlag is equal to 1, it indicates that the node corresponding to the STSplitFlag is continued to be divided according to the binary tree division manner. The division direction identifier is STSplitDir. If the value of STSplitDir is equal to 0, it indicates that the node corresponding to the STSplitDir is divided according to the horizontal binary division manner; if the value of STSplitDir is equal to 1, it indicates that the node divides the node corresponding to the STSplitDir according to the vertical division method.

S803. If the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is not continued to be divided according to the division manner of the second-level coding tree, the decoding end device parses the code stream, The node division mode information of the third-level coding tree is obtained.

If the division manner corresponding to the first node in the second-level coding tree does not continue to be divided according to the division manner of the second-level coding tree, the first node is a leaf node of the second-level coding tree. The first node may be divided according to the division manner of the third-level coding tree. Therefore, the first node is the root node of the third-level coding tree. The division manner corresponding to the third-level coding tree in this embodiment includes a tri-tree division.

The first node is the root node of the third-level coding tree, and the third-level coding tree is divided into three-tree trees. Therefore, the three child nodes of the first node are the leaf nodes of the third-level coding tree.

Specifically, if the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is not continued to be divided according to the division manner of the second-level coding tree, the decoding end device parses the CTU code. The stream obtains a fifth identifier (such as TTSplitMode) for indicating how to divide a node in the third-level coding tree, that is, the fifth identifier indicates node division manner information of the third-level coding tree.

In this embodiment, the node division manner corresponding to the third-level coding tree includes a tri-tree division. Therefore, the fourth identifier in this embodiment may be used to indicate that a node is not divided, and may also be used to indicate that it corresponds to a certain node. It is divided into horizontal three points or vertical three points.

Exemplarily, the fifth identifier is represented by TTSplitMode, and the value of TTSplitMode is 0, indicating that the node corresponding to the TTSplitMode is not further divided; the value of TTSplitMode is 1 or 2, respectively, indicating that the corresponding mode corresponding to the node corresponding to TTSplitMode is horizontal. Three points or three vertical points.

Optionally, the fifth identifier in this embodiment may include a node partition identifier (such as TTSplitFlag) for indicating whether to divide according to a tri-tree partition manner, and a split direction identifier (such as TTSplitDir) for indicating a direction of the tri-tree partition.

Exemplarily, the node division identifier is TTSplitFlag. If the value of TTSplitFlag is equal to 0, it indicates that the node corresponding to the TTSplitFlag is not divided. If the value of TTSplitFlag is equal to 1, it indicates that the node corresponding to the TTSplitFlag is continued to be divided according to the tri-tree partition manner. The division direction identifier is TTSplitDir. If the value of TTSplitDir is equal to 0, it means that the node corresponding to the TTSplitDir is divided according to the horizontal three-point division manner; if the value of TTSplitDir is equal to 1, it indicates that the section is divided into the TTSplitDir according to the vertical three-point division manner. node.

S804. If the node division mode information of the third-level coding tree indicates that the division manner corresponding to the first node is a tri-tree division, the decoding end device parses the code stream to obtain coding information of three child nodes of the first node.

Wherein, one child node of the first node corresponds to one CU.

S804 may refer to the above S603, except that the decoding end device in S804 acquires the coding information of the leaf node of the third-level coding tree.

Illustratively, Table 5 shows a syntax table of the third level coding tree in this embodiment. In Table 5, when the second-level coding tree level stDepth of the node is satisfied to be smaller than the preset maximum second-level coding tree level maxSTDepth, the width and height of the image area corresponding to the node are less than or equal to the threshold maxSTSize, and the image corresponding to the node If the width or height of the area is greater than 2 times the threshold minCUSize, the decoding device parses TTSplitMode; otherwise, the value of TTSplitMode is 0. If the value of TTSplitMode is 0, the node corresponding to the TTSplitMode is a leaf node of the third-level coding tree, and the decoding device parses the CU syntax structure coding_unit() to obtain CU information; if the value of TTSplitMode is 1 or 2, decoding The terminal device sequentially parses the coding_unit() for the three child nodes of the node corresponding to the TTSplitMode to obtain CU information.

S805. The decoding end device performs decoding and reconstruction on the coding unit according to the decoding information of the three child nodes of the first node, to obtain an image corresponding to the image data.

S805 can refer to the above S604, and details are not described herein again.

Compared with the embodiment shown in FIG. 6 and FIG. 7 , the division manner corresponding to the second-level coding tree in this embodiment includes only the binary tree division, and the division manner corresponding to the third-level coding tree includes the tri-tree division, and the third The three child nodes of the root node of the level coding tree are the leaf nodes of the third-level coding tree, and the decoding end device can obtain the node division mode information of the second-level coding tree and the node division manner of the third-level coding tree more quickly. The information further increases the decoding rate.

table 5

In addition, the embodiment of the present application further provides an encoding method of image data, which can be applied to the image processing system shown in FIG. 4.

As shown in FIG. 9, the encoding method of the image data provided by the embodiment of the present application includes:

S900. The encoding end device determines a CTU corresponding to the image block to be encoded.

As can be seen from the foregoing description, an image is composed of a plurality of CTUs, and a CTU generally corresponds to a square image area. After acquiring an image, the encoding end device performs encoding processing on each CTU of the image.

The coding process of the CPT is the same for each CTU. Therefore, the coding process of one CTU by the coding end device is taken as an example for description.

S901: The coding end device divides the CTU according to a node division manner corresponding to the first-level coding tree, to obtain a leaf node of the first-level coding tree.

The root node of the first-level coding tree corresponds to the CTU, and the node division manner corresponding to the first-level coding tree is a quad-tree partition.

Specifically, the encoding end device determines the CTU as the root node of the first-level coding tree, and uses the QT division manner to recursively divide the CTU into at least one leaf node.

After acquiring the at least one leaf node of the first-level coding tree, the encoding end device determines each leaf node of the first-level coding tree as the root node of the second-level coding tree, and sequentially pairs each of the second-level coding trees. The root nodes perform the following steps until information about all leaf nodes of the second level coding tree is obtained. The embodiment of the present application is described by taking the processing of the first node in the second-level coding tree by the encoding end device as an example.

S902: The encoding end device determines, according to the preset condition, a division manner that can be used by the first node in the second-level coding tree, where the preset condition includes: if the division manner corresponding to the parent node of the first node is a tri-tree division, determining Does not divide the first node.

Generally, in the case where the division of the first node is without any restriction, the division manner that the first node can use includes no division, horizontal dichotomy, horizontal trisection, vertical dichotomy, vertical trisection, and quadtree division. . In this case, the encoding end device needs to calculate the RD cost of the six partitioning modes in turn, resulting in high coding complexity.

The embodiment of the present application provides a preset condition for limiting a division manner that can be used by the first node. The preset condition includes: if the parent node of the first node uses the tri-tree partitioning manner, it is determined that the first node is not divided. In this way, after the coding end device determines that the parent node of the first node is divided by the TT division mode, the first node is no longer divided, and the RD cost of the six division manners for the first node is not required to be calculated, thereby reducing the coding complexity.

In addition, the preset condition further includes: when the width of the image region corresponding to the first node, the height of the image region corresponding to the first node, and the second-level coding tree hierarchy of the first node satisfy a certain condition, determining that the parameter is not allowed The first node uses a first division manner, and the first division manner is at least one of a horizontal dichotomy, a horizontal triad, a vertical dichotomy, a vertical triad, and a quadtree division manner.

Exemplarily, when the width of the image area corresponding to the first node is equal to the width of the preset minimum CU, the first node is not allowed to use two division modes: vertical binary and vertical three; when the first node corresponds to When the height of the image area is equal to twice the height of the preset minimum CU, the first node is not allowed to use the horizontal three-point division manner; when the first node is the node of the second-level coding tree, the first node is not allowed to use the fourth node. The cross-tree partitioning mode; when the second-level coding tree level of the first node is equal to the preset maximum second-level coding tree hierarchy (represented by maxSTDepth), it is determined that the first node is not divided.

Of course, the foregoing example is only an example of the preset condition in the embodiment of the present application, and the preset condition in the embodiment of the present application may further include restrictions of other types of division manner.

S903. If the division manner that can be used by the first node is not divided, the encoding end device encodes the CU corresponding to the first node, and obtains a coding unit code stream corresponding to the CU.

If the division mode that the first node can use is no division, the first node is a leaf node of the second-level coding tree, and the first node corresponds to one CU. The encoding end device encodes the CU corresponding to the first node to obtain a coded unit code stream with the CU.

Specifically, the CU coding includes a prediction, a transform, a quantization, and an entropy coding. For a certain CU, the encoding end device encodes the CU, and the process of obtaining the CU code stream of the CU mainly includes:

(1) The encoding end device selects the intra prediction or the inter prediction according to the prediction mode to obtain the predicted pixel of the CU.

(2) The encoding end device changes and quantizes the residual between the original pixel of the CU and the predicted pixel of the CU to obtain a transform coefficient, and performs inverse quantization and inverse transform processing on the obtained transform coefficient, thereby obtaining the CU. Rebuild the residual.

(3) The encoding end device adds the predicted pixel of the CU and the reconstructed residual of the CU, and performs loop filtering processing to obtain the reconstructed pixel of the CU.

(4) The encoding end device entropy encodes the prediction mode and the transform coefficient of the CU to obtain a CU code stream.

For the detailed process of obtaining the CU code stream of the CU, the method for generating the CU code stream of the CU may refer to the existing method for generating the CU code stream, and details are not described herein again.

S904. If the division manner that the first node can use does not include no division, the encoding end device calculates an RD cost of each of the division manners that the first node can use.

For a certain division manner that can be used by the first node, the coding end device divides the first node by using the division manner, and obtains all the CUs after the first node is divided by the division manner, and the coding end device calculates the RD cost of each CU. The sum of the RD costs of all CUs is determined as the RD cost of the division mode.

Optionally, for any CU, the RD cost of the CU is equal to the sum of the Sum of Squared Errors (SSE) of the reconstructed distortion of the pixel included in the CU and the estimated number of bits of the CU corresponding code stream. with.

S905. The coding end device determines, by using a minimum rate distortion cost, a division manner as a target division manner corresponding to the first node.

S906. The coding end device divides the first node by using a target division manner corresponding to the first node.

After the coding end device divides the first node by using the target division manner corresponding to the first node, the S902-S906 is sequentially executed for each child node of the first node until all the leaf nodes in the second-level coding tree are acquired.

Each leaf node of the second-level coding tree corresponds to one CU, and after obtaining all the leaf nodes of the second-level coding tree, the coding end device can acquire the CU corresponding to each leaf node of the second-level coding tree. It can be seen from S903 that the encoding end device encodes one CU to obtain the CU code stream corresponding to the CU. Therefore, the encoding end device can obtain at least one CU code stream. In this way, the encoding end device can obtain the CTU code stream according to the at least one CU code stream, the node division manner information corresponding to the first level coding tree, and the node division manner information corresponding to the second level coding tree, thereby generating a code stream including the image data. .

The embodiment of the present application provides a decoding end device, which is used to perform the steps performed by the decoding end device in the decoding method of the above image data. The decoding device provided by the embodiment of the present application may include a module corresponding to the corresponding step.

The embodiment of the present application may perform the division of the function module on the decoding end device according to the foregoing method example. For example, each function module may be divided according to each function, or two or more functions may be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. The division of modules in the embodiments of the present application is schematic, and is only a logical function division, and may be further divided in actual implementation.

FIG. 10 shows a possible structural diagram of the terminal device involved in the foregoing embodiment in the case where the respective functional modules are divided by corresponding functions. As shown in FIG. 10, the decoding end device includes an obtaining module 1000, a parsing module 1001, and a decoding and resolving module 1010. The obtaining module 1000 is configured to support the decoding end device to perform S600, S700, and/or S800, etc. in the foregoing embodiments, and/or other processes for the techniques described herein; the parsing module 1001 is configured to support the decoding end device Performing S601, S602, S603, S701, S702, S703, S704, S801, S802, S803, and/or S804, etc. in the above embodiments, and/or other processes for the techniques described herein; decoding reconstruction module 1010 is for supporting the decoding device to perform S604, S705, and/or S805, etc. in the above embodiments, and/or other processes for the techniques described herein. All the related content of the steps involved in the foregoing method embodiments may be referred to the functional descriptions of the corresponding functional modules, and details are not described herein again. The decoding device provided by the embodiment of the present application includes, but is not limited to, the foregoing module. For example, the decoding device may further include a storage module 1011. The storage module 1011 can be used to store program code and data of the decoding end device.

In the case of an integrated unit, the parsing module 1001 and the decoding and resolving module 1011 in the embodiment of the present application may be the processor 57 in FIG. 5, and the obtaining module 1000 may be the RF circuit 50 in FIG. 5 and the RF The antenna 50 is connected to the circuit 50, and the memory module 1011 may be the memory 51 in FIG.

When the decoding device operates, the decoding device performs a decoding method of the image data of the embodiment shown in any of Figs. 6-8. For the decoding method of the specific image data, refer to the related description in the embodiment shown in any of the above-mentioned figures in FIG. 6 to FIG. 8 , and details are not described herein again.

Another embodiment of the present application further provides a computer readable storage medium including one or more program codes, the one or more programs including instructions, when a processor in a decoding end device is executing the In the program code, the decoding device performs a decoding method of the image data as shown in any of Figs. 6-8.

In another embodiment of the present application, there is also provided a computer program product comprising computer executed instructions stored in a computer readable storage medium; at least one processor of the decoding end device is The computer readable storage medium reads the computer execution instructions, and the at least one processor executes the computer execution instructions such that the decoding end device implements the decoding end device in the decoding method for performing the image data shown in any of FIGS. 6-8 A step of.

The embodiment of the present application provides an encoding end device, which is used to perform the steps performed by the encoding end device in the decoding method of the above image data. The encoding end device provided by the embodiment of the present application may include a module corresponding to the corresponding step.

The embodiment of the present application may perform the division of the function module on the encoding end device according to the foregoing method example. For example, each function module may be divided according to each function, or two or more functions may be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. The division of modules in the embodiments of the present application is schematic, and is only a logical function division, and may be further divided in actual implementation.

FIG. 11 is a schematic diagram showing a possible structure of the terminal device involved in the foregoing embodiment, in the case where the respective functional modules are divided by corresponding functions. As shown in FIG. 11, the encoding end device includes a determining module 1100, a dividing module 1101, an encoding module 1110, and a computing module 1111. The determining module 1100 is configured to support the encoding end device to perform S900, S902, and/or S905 and the like in the above embodiments, and/or other processes for the techniques described herein; the dividing module 1101 is configured to support the encoding end device Performing S901, and/or S906, etc. in the above embodiments, and/or other processes for the techniques described herein; the encoding module 1110 is configured to support the encoding end device to perform S903 in the above embodiment, and/or Other processes of the techniques described herein; computing module 1111 is for supporting the encoding end device to perform S904 in the above-described embodiments, and/or other processes for the techniques described herein. All the related content of the steps involved in the foregoing method embodiments may be referred to the functional descriptions of the corresponding functional modules, and details are not described herein again. Certainly, the encoding end device provided by the embodiment of the present application includes but is not limited to the foregoing module. For example, the encoding end device may further include a storage module 1102, a sending module 1103, and a receiving module 1104. The storage module 1102 can be used to store program code and data of the encoding end device. The transmitting module 1103 and the receiving module 1104 are configured to communicate with other devices.

The determining module 1100, the dividing module 1101, the encoding module 1110, and the computing module 1111 in the embodiment of the present application may be the processor 57 in FIG. 5, and the sending module 1103 and the receiving module 1104 may be in the form of an integrated unit. The RF circuit 50 in 5 and the antenna connected to the RF circuit 50, the memory module 1102 may be the memory 51 in FIG.

When the encoding device operates, the encoding device performs a decoding method of the image data of the embodiment shown in FIG. For the decoding method of the specific image data, refer to the related description in the embodiment shown in FIG. 9 above, and details are not described herein again.

Another embodiment of the present application further provides a computer readable storage medium comprising one or more program codes, the one or more programs including instructions, when a processor in an encoding end device is executing the At the time of the program code, the encoding side device executes the decoding method of the image data as shown in FIG.

In another embodiment of the present application, there is also provided a computer program product comprising computer executed instructions stored in a computer readable storage medium; at least one processor of the encoding end device is The computer readable storage medium reads the computer execution instructions, and the at least one processor executes the computer execution instructions such that the encoding end device implements the step of the encoding end device in the decoding method of the image data shown in FIG.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using a software program, it may occur in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present application are generated in whole or in part. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be from a website site, computer, server or data center Transfer to another website site, computer, server, or data center by wire (eg, coaxial cable, fiber optic, digital subscriber line (DSL), or wireless (eg, infrared, wireless, microwave, etc.). The computer readable storage medium can be any available media that can be accessed by a computer or a data storage device such as a server, data center, or the like that includes one or more available media. The usable medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (such as a solid state disk (SSD)).

Through the description of the above embodiments, those skilled in the art can clearly understand that for the convenience and brevity of the description, only the division of the above functional modules is illustrated. In practical applications, the above functions can be allocated according to needs. It is completed by different functional modules, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be used. The combination may be integrated into another device, or some features may be ignored or not performed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in an electrical, mechanical or other form.

The units described as separate components may or may not be physically separated, and the components displayed as units may be one physical unit or multiple physical units, that is, may be located in one place, or may be distributed to multiple different places. . Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a standalone product, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present application may be embodied in the form of a software product in the form of a software product in essence or in the form of a contribution to the prior art, and the software product is stored in a storage medium. A number of instructions are included to cause a device (which may be a microcontroller, chip, etc.) or a processor to perform all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like, which can store program codes. .

The foregoing is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto, and any changes or substitutions within the technical scope of the present application should be covered by the scope of the present application. . Therefore, the scope of protection of the present application should be determined by the scope of the claims.

Claims

A method for decoding image data, characterized in that the decoding method comprises:

Obtaining a code stream containing the image data;

Parsing the code stream to obtain node partitioning mode information of the first-level coding tree, where a root node of the first-level coding tree corresponds to a coding tree unit CTU, and a leaf node of the first-level coding tree is a Determining a node partitioning manner corresponding to node partitioning mode information of the first-level coding tree and indicating a root node of the first-level coding tree;

Parsing the code stream to obtain node partitioning mode information of the second-level coding tree, where a root node of the second-level coding tree is a leaf node of the first-level coding tree;

If the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is a tri-tree partition, parsing the code stream to obtain three child nodes of the first node. Encoding information, wherein one of the child nodes of the first node corresponds to one coding unit CU;

Decoding and reconstructing the coding unit according to coding information of three child nodes of the first node to obtain an image corresponding to the image data.
The decoding method according to claim 1, wherein the node division manner corresponding to the first-level coding tree is different from the node division manner corresponding to the second-level coding tree.
The decoding method according to claim 1 or 2, wherein the node division manner corresponding to the first-level coding tree comprises a quad-tree division, and the node division manner corresponding to the second-level coding tree includes a binary tree division and Trigeminal tree division.
A method for decoding image data, characterized in that the decoding method comprises:

Obtaining a code stream containing the image data;

Parsing the code stream to obtain node partitioning mode information of the first-level coding tree, where a root node of the first-level coding tree corresponds to a coding tree unit CTU, and a leaf node of the first-level coding tree is a Determining a node partitioning manner corresponding to node partitioning mode information of the first-level coding tree and indicating a root node of the first-level coding tree;

Parsing the code stream to obtain node partitioning mode information of the second-level coding tree, where a root node of the second-level coding tree is a leaf node of the first-level coding tree;

If the node division mode information of the second-level coding tree indicates that the division manner corresponding to the first node in the second-level coding tree is not continued to be divided according to the division manner of the second-level coding tree, parsing the code stream, and obtaining The node division mode information of the third level coding tree, wherein the root node of the third level coding tree is the first node;

If the node division mode information of the third-level coding tree indicates that the division manner corresponding to the first node is a tri-tree partition, parsing the code stream to obtain coding information of three child nodes of the first node, where One of the child nodes of the first node corresponds to one coding unit CU;

Decoding and reconstructing the coding unit according to decoding information of three child nodes of the first node to obtain an image corresponding to the image data.
The decoding method according to claim 4, wherein the node partitioning manner corresponding to the first-level coding tree comprises a quadtree partitioning, and the node partitioning manner corresponding to the second-level coding tree comprises a binary tree partitioning, The node division manner corresponding to the third-level coding includes tri-tree division.
A method for decoding image data, characterized in that the decoding method comprises:

Obtaining a code stream containing the image data;

Parsing the code stream to obtain a tri-tree leaf node pattern identifier, where the tri-tree leaf node pattern identifier is used to indicate whether to limit the node obtained by the tri-tree partition to continue to divide;

Parsing the code stream to obtain node partitioning mode information of the first-level coding tree, where a root node of the first-level coding tree corresponds to a coding tree unit CTU, and a leaf node of the first-level coding tree is a Determining a node partitioning manner corresponding to node partitioning mode information of the first-level coding tree and indicating a root node of the first-level coding tree;

Parsing the code stream to obtain node partitioning mode information of the second-level coding tree, where a root node of the second-level coding tree is a leaf node of the first-level coding tree;

If the node division mode information of the second-level coding tree indicates that the first node in the second-level coding tree corresponds to a tri-tree partition, and the tri-tree leaf mode identifier indicates that the node obtained by limiting the tri-tree partition continues Performing division, parsing the code stream, and obtaining coding information of three child nodes of the first node, where one of the child nodes of the first node corresponds to one coding unit CU;

Decoding and reconstructing the coding unit according to coding information of three child nodes of the first node to obtain an image corresponding to the image data.
The decoding method according to claim 6, wherein the node division manner corresponding to the first-level coding tree is different from the node division manner corresponding to the second-level coding tree.
A method for encoding image data, characterized in that the encoding method comprises:

Determining a coding tree unit CTU corresponding to the image block to be encoded;

And dividing the CTU according to a node division manner corresponding to the first-level coding tree, to obtain a leaf node of the first-level coding tree, where a root node of the first-level coding tree corresponds to the CTU;

And determining, according to the preset condition, a division manner that can be used by the first node in the second-level coding tree, where the preset condition includes: if the division manner corresponding to the parent node of the first node is a tri-tree division, determining not to divide The first node, the root node of the second level coding tree is a leaf node of the first level coding tree;

If the division manner that can be used by the first node is not divided, the coding unit CU corresponding to the first node is encoded to obtain a coding unit code stream corresponding to the coding unit.
The coding method according to claim 8, wherein the node division manner corresponding to the first-level coding tree is different from the node division manner corresponding to the second-level coding tree.
The encoding method according to claim 8 or 9, wherein the encoding method further comprises:

Calculating a rate-distortion cost for each of the partitioning modes that the first node can use if the partitioning manner that the first node can use does not include no partitioning;

Determining, by using a minimum rate distortion cost, a division manner corresponding to the target division manner corresponding to the first node;

And dividing the first node by using a target division manner corresponding to the first node.
The coding method according to any one of claims 8 to 10, wherein the node division manner corresponding to the first-level coding tree comprises a quad-tree division, and the node division manner corresponding to the second-level coding tree Includes binary tree partitioning and trigeminal tree partitioning.
A decoding end device, comprising:

An obtaining module, configured to obtain a code stream that includes the image data;

a parsing module, configured to parse the code stream obtained by the acquiring module, to obtain node partitioning mode information of the first-level coding tree, where a root node of the first-level coding tree corresponds to a coding tree unit CTU The leaf node of the first-level coding tree is indicated by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree, and is used for parsing the code Streaming, obtaining node partitioning mode information of the second level coding tree, wherein a root node of the second level coding tree is a leaf node of the first level coding tree, and for if the second level coding tree The node division mode information indicates that the division manner corresponding to the first node in the second-level coding tree is a tri-tree partition, and the code stream is parsed to obtain coding information of three child nodes of the first node, where the One of the child nodes of a node corresponds to one coding unit CU;

And a decoding and reconstruction module, configured to perform decoding and reconstruction on the coding unit according to the coding information of the three child nodes of the first node obtained by the analysis module, to obtain an image corresponding to the image data.
The decoding device according to claim 12, wherein the node division manner corresponding to the first-level coding tree is different from the node division manner corresponding to the second-level coding tree.
The decoding device according to claim 12 or 13, wherein the node division manner corresponding to the first level coding tree comprises a quadtree partition, and the node division manner corresponding to the second level coding tree comprises a binary tree division. And trigeminal division.
A decoding end device, comprising:

An obtaining module, configured to obtain a code stream that includes the image data;

a parsing module, configured to parse the code stream obtained by the acquiring module, to obtain node partitioning mode information of the first-level coding tree, where a root node of the first-level coding tree corresponds to a coding tree unit CTU The leaf node of the first-level coding tree is indicated by the node division manner corresponding to the node division mode information of the first-level coding tree and the root node of the first-level coding tree, and is used for parsing the code Streaming, obtaining node partitioning mode information of the second level coding tree, wherein a root node of the second level coding tree is a leaf node of the first level coding tree, and for if the second level coding tree The node division mode information indicates that the first node in the second-level coding tree has a division manner that does not continue to be divided according to the division manner of the second-level coding tree, and parses the code stream to obtain a node division of the third-level coding tree. Mode information, where the root node of the third-level coding tree is the first node, and if the node division mode information of the third-level coding tree indicates that the first node corresponds to Ternary tree is divided to division manner, parsing the bitstream, the encoded information to obtain three sub-nodes of the first node, wherein a first node of the child nodes corresponding to one coding unit of the CU;

And a decoding and reconstruction module, configured to perform decoding and reconstruction on the coding unit according to the coding information of the three child nodes of the first node obtained by the analysis module, to obtain an image corresponding to the image data.
The decoding device according to claim 15, wherein the node division manner corresponding to the first level coding tree comprises a quadtree partition, and the node division manner corresponding to the second level coding tree comprises a binary tree division. The node division manner corresponding to the third-level coding includes tri-tree partitioning.
A decoding end device, comprising:

An obtaining module, configured to obtain a code stream that includes the image data;

a parsing module, configured to parse the code stream obtained by the acquiring module, to obtain a tri-tree leaf node pattern identifier, where the tri-tree leaf node pattern identifier is used to indicate whether the node obtained by limiting the tri-tree partitioning is further divided, and used for Parsing the code stream to obtain node partitioning mode information of the first-level coding tree, where a root node of the first-level coding tree corresponds to a coding tree unit CTU, and a leaf node of the first-level coding tree is a Deriving a node partitioning manner corresponding to the node partitioning mode information of the first-level coding tree and indicating the root node of the first-level coding tree, and parsing the codestream to obtain a node partitioning manner of the second-level coding tree Information, wherein a root node of the second-level coding tree is a leaf node of the first-level coding tree, and information for node division mode if the second-level coding tree indicates a second-level coding tree The division manner corresponding to the first node is a tri-tree division, and the tri-tree leaf node pattern identifier indicates that the node obtained by limiting the tri-tree division continues to be divided. And parsing the code stream to obtain coding information of three child nodes of the first node, where one of the child nodes of the first node corresponds to one coding unit CU;

And a decoding and reconstruction module, configured to perform decoding and reconstruction on the coding unit according to the coding information of the three child nodes of the first node obtained by the analysis module, to obtain an image corresponding to the image data.
The decoding device according to claim 17, wherein the node division manner corresponding to the first-level coding tree is different from the node division manner corresponding to the second-level coding tree.
An encoding end device, comprising:

a determining module, configured to determine a coding tree unit CTU corresponding to the image block to be encoded;

a dividing module, configured to divide the CTU determined by the determining module according to a node division manner corresponding to the first-level coding tree, to obtain a leaf node of the first-level coding tree, and a root of the first-level coding tree The node corresponds to the CTU;

The determining module is further configured to determine, according to a preset condition, a division manner that can be used by the first node in the second-level coding tree, where the preset condition includes: if the parent node of the first node corresponds to a division manner For dividing into a tri-tree, determining that the first node is not divided, and the root node of the second-level coding tree is a leaf node of the first-level coding tree;

And an encoding module, configured to: if the partitioning mode that is determined by the determining, by the determining module, is not divided, the coding unit CU corresponding to the first node is encoded, and the coding corresponding to the coding unit is obtained. Unit code stream.
The encoding device according to claim 19, wherein the node division manner corresponding to the first-level coding tree is different from the node division manner corresponding to the second-level coding tree.
The encoding device according to claim 19 or 20, wherein the encoding device further comprises a computing module:

The calculating module is configured to calculate a rate distortion cost of each of the partitioning modes that the first node can use if the determining module determines that the dividing manner that the first node can use does not include no partitioning;

The determining module is further configured to determine a partitioning manner corresponding to a minimum rate distortion cost as a target partitioning manner corresponding to the first node;

The dividing module is specifically configured to divide the first node by using a target dividing manner corresponding to the first node determined by the determining module.
The coding end device according to any one of claims 19 to 21, wherein the node division manner corresponding to the first level coding tree comprises a quadtree division, and the node division corresponding to the second level coding tree The modes include binary tree partitioning and tri-tree partitioning.
A decoding end device, characterized in that: the decoding end device comprises: one or more processors, a memory, a communication interface;

The memory, the communication interface is coupled to the one or more processors; the memory is for storing computer program code, the computer program code comprising instructions when the one or more processors execute the instructions The decoding end device performs the decoding method of the image data according to any one of claims 1-7.
An encoding end device, wherein the encoding end device comprises: one or more processors, a memory, and a communication interface;

The memory, the communication interface is coupled to the one or more processors; the memory is for storing computer program code, the computer program code comprising instructions when the one or more processors execute the instructions The encoding end device performs the encoding method of the image data according to any one of claims 8-11.
A computer readable storage medium having stored therein instructions, wherein when the instructions are run on a decoding end device, causing the decoding end device to perform as in claims 1-7 A method of decoding image data as described in any one of the preceding claims.
A computer readable storage medium having stored therein instructions, wherein when the instructions are run on an encoding end device, causing the encoding end device to perform as in claims 8-11 A method of encoding image data as described in any one of the preceding claims.