CN102761742B - Transform block division methods, transform block divides coding method and the coding/decoding method of parameter - Google Patents

Abstract

The invention provides a transformation block division method, a division parameter coding method and a decoding method of the transformation block. The transformation block division method includes: obtaining the minimum value of the size of the preset transformation block; when performing non-square division on the transformation block, if the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block, then Stop dividing the transform block. In the embodiment of the present invention, when performing non-square division on the transformation block, when one of the width or height of the transformation block is equal to the minimum size of the preset transformation block, the division is stopped.

Description

Transformation block division method, encoding method and decoding method of transformation block division parameters

technical field

Embodiments of the present invention relate to image coding technology, and in particular, to a transform block division method, an encoding method and a decoding method of transform block division parameters.

Background technique

In order to reduce the bandwidth occupied by video transmission, video data needs to be encoded. Among them, the inter-frame compression method is a common video encoding technology, which can compress the video image to be transmitted and reduce the data of video transmission.

The inter-frame compression method is a video coding technology based on motion estimation. The process of encoding video images at the video encoding end includes: first, dividing the image block to be encoded into several equal-sized sub-image blocks; then, for each sub-image block Image block, search for the image block that best matches the current sub-image block in the reference image as the prediction block; then, subtract the sub-image block from the corresponding pixel value of the prediction block to obtain a residual, and obtain each sub-image The residuals corresponding to the blocks are combined to obtain the residuals of the image blocks; then the values obtained by transforming and quantizing the residuals of the image blocks are entropy encoded; finally, the bit stream and motion vector information obtained by the entropy encoding are concurrently To the decoding end, wherein the motion vector information represents the position difference between the current sub-image block and the prediction block. After receiving the bit stream and motion vector information sent by the encoding end, the decoding end performs the opposite process to that of the encoding end to obtain the original data of the corresponding image block. At present, in the process of image coding, the residual of the image block is transformed by using the transformation block (also called the change matrix) to transform the residual to obtain the transformation coefficient matrix to remove the redundant information of the image block and improve Coding efficiency of image blocks. Due to the different distribution rules of the residuals of image blocks, using a transformation block of a certain size to transform them often does not achieve a good transformation effect, so it is necessary to use transformation blocks of different sizes to transform the residuals of image blocks. Perform transformation processing to obtain the best transformation effect.

In the existing image block encoding process, it is necessary to divide the transformation block to obtain a transformation block suitable for transforming the residual of the image block, wherein the initial size of the transformation block is usually square, that is, the height and width of the transformation block are equal . When the traditional method divides the transformation block, it adopts square division, that is, divides the transformation block into multiple square sub-transformation blocks with equal width and height, and then uses the square transformation block to transform the residual of the image block.

Because when the image block is divided, non-square division methods such as horizontal division and vertical division will be used, and this non-square division will reflect the texture information of the image block. At this time, if the square transformation block is used to perform During the transformation process, the square transformation block may span the residuals corresponding to the two adjacent sub-image blocks. Since the residuals corresponding to the two adjacent sub-image blocks will have jumpy transformations, at this time, when the square transformation block is used for transformation , it will make the transformation effect weaken, and the redundant information of the image block cannot be effectively removed, and the coding efficiency will be reduced. For this reason, the prior art also proposes a method for transforming the residual of an image block by using a non-square transform block, wherein, when dividing the transform block, the division method is consistent with the image block, and the division is obtained by The shape of the sub-transform block is consistent with the size of the sub-image block, so that the problem of not being able to effectively remove redundant information of the image block exists when the square transform block is used to process the residual of the image block. In addition, in the process of dividing the transformation block, the division parameter of the transformation block needs to be encoded, and each transformation block needs to encode the division parameter of the transformation block to indicate whether the transformation block needs to be divided.

However, when dividing the transformation, the minimum value of the size of the transformation block is usually preset, while the existing transformation block division process using non-square transformation blocks divides the width and height of the transformation block into preset transformation blocks When the minimum value of the size of , the division will stop. In this way, when dividing the transformation block, there may be a division method that uses horizontal division, vertical division, or horizontal division and vertical division at the same time. The encoding of the transformation block parameters is complicated. As a result, the division logic of the transform block is complicated, and the divided transform block will also affect the encoding efficiency of the image block, increasing the complexity of encoding.

Contents of the invention

Embodiments of the present invention provide a transformation block division method, a coding method and a decoding method of transformation block division parameters, which can effectively divide transformation blocks and improve the coding efficiency of image blocks.

An embodiment of the present invention provides a transformation block division method, including:

Obtain the minimum value of the size of the preset transformation block;

When performing non-square division of the transformation block, if the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block, then stop dividing the transformation block;

Wherein, the non-square division refers to a division method of dividing an image block or a transform block into widths and heights.

An embodiment of the present invention further provides a coding method for transforming block division parameters, including:

Obtain the minimum value of the size of the preset transformation block;

According to the relationship between the size of the transform block and the minimum value of the size of the preset transform block, determine whether to encode the division parameter of the transform block;

The division parameter of the transform block is used to indicate whether to divide the transform block or not.

The embodiment of the present invention also provides a decoding method for transforming block division parameters, which is characterized in that it includes:

Obtain the minimum value of the size of the preset transformation block;

According to the relationship between the size of the transform block and the minimum value of the size of the preset transform block, determine whether to decode the division parameter of the transform block;

The division parameter of the transform block is used to indicate whether to divide the transform block or not.

In addition, an embodiment of the present invention also provides an apparatus for dividing transform blocks, including:

a size obtaining module, configured to obtain the minimum value of the size of the preset transformation block;

A transformation block division module, configured to stop dividing the transformation block if the width or height of the transformation block is equal to the minimum size of the preset transformation block when performing non-square division of the transformation block;

Wherein, the minimum value of the size of the preset transformation block is the minimum value of the width or height of the transformation block, or the minimum value of the average value of the sum of width and height; the non-square division refers to dividing the image block or the transformation block Divide into division methods ranging in width and height.

An embodiment of the present invention provides an encoding device for transforming block division parameters, including:

a size obtaining module, configured to obtain the minimum value of the size of the preset transformation block;

A parameter encoding module, configured to determine whether to encode the division parameter of the transform block according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block;

The division parameter of the transform block is used to indicate whether to divide the transform block or not.

An embodiment of the present invention provides a decoding device for transforming block division parameters, including:

a size obtaining module, configured to obtain the minimum value of the size of the preset transformation block;

A parameter decoding module, configured to judge whether to decode the division parameter of the transform block according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block;

The division parameter of the transform block is used to indicate whether to divide the transform block or not.

An embodiment of the present invention provides an image encoding and decoding system, including:

An encoding device for transform block division parameters, configured to determine whether to encode the division parameters of the transform block according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block;

The decoding device of the transformation block division parameter is used to judge whether to decode the division parameter of the transformation block according to the relationship between the size of the transformation block and the minimum value of the size of the preset transformation block;

Wherein, the division parameter of the transform block is used to indicate whether to divide the transform block or not to divide

The transformation block division method provided by the embodiment of the present invention, the encoding method and decoding method of the transformation block division parameters, when performing non-square division on the transformation block, as long as one of the width or height of the transformation block is equal to the size of the preset transformation block If it is the minimum value, the division of the transform block is stopped, and the coding efficiency of the image block is improved.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Figures 1a-1d are structural schematic diagrams of image blocks divided by symmetrical division;

Fig. 2a-Fig. 2d are structural schematic diagrams of image blocks divided by asymmetrical division;

Fig. 3a-Fig. 3c are schematic diagrams of the size of the change block used by the image block;

FIG. 4 is a schematic flowchart of a transform block division method provided by Embodiment 1 of the present invention;

FIG. 5 is a schematic flowchart of a transform block division method provided in Embodiment 2 of the present invention;

FIG. 6 is a schematic flowchart of a transform block division method provided by Embodiment 3 of the present invention;

FIG. 7 is a schematic flowchart of a method for encoding transformation block division parameters provided by Embodiment 4 of the present invention;

FIG. 8 is a schematic flowchart of a decoding method for transform block division parameters provided in Embodiment 5 of the present invention;

FIG. 9 is a schematic structural diagram of an apparatus for dividing transform blocks according to Embodiment 6 of the present invention;

FIG. 10 is a schematic structural diagram of an apparatus for dividing transform blocks provided by Embodiment 7 of the present invention;

FIG. 11 is a schematic structural diagram of an apparatus for dividing transform blocks provided by Embodiment 8 of the present invention;

FIG. 12 is a schematic structural diagram of an apparatus for dividing transform blocks provided by Embodiment 9 of the present invention;

FIG. 13 is a schematic structural diagram of an encoding device for transforming block division parameters provided by Embodiment 10 of the present invention;

FIG. 14 is a schematic structural diagram of an encoding device for transforming block division parameters provided by Embodiment 11 of the present invention;

FIG. 15 is a schematic structural diagram of an encoding device for transforming block division parameters provided by Embodiment 12 of the present invention;

FIG. 16 is a schematic structural diagram of a decoding device for transforming block division parameters provided by Embodiment 13 of the present invention;

FIG. 17 is a schematic structural diagram of a decoding device for transforming block division parameters provided by Embodiment 14 of the present invention;

FIG. 18 is a schematic structural diagram of a decoding device for transforming block division parameters provided by Embodiment 15 of the present invention;

FIG. 19 is a schematic structural diagram of an image encoding and decoding system provided by Embodiment 16 of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are the Some, but not all, embodiments are invented. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In order to facilitate the understanding of the technical solutions of the embodiments of the present invention, the division of image blocks and the division of transformation blocks in video coding are firstly described below.

The division of image blocks:

In existing video coding systems and decoding standards, such as Moving Picture Experts Group (Moving Picture Experts Group, MPEG), Enhanced Video Coding (Advanced Video Coding, H.264/AVC), an image block, or macroblock (macroblock) ), super-macroblock (super-macroblock), etc., can be divided into several sub-image blocks, the size of these sub-image blocks is 16x16, 16x8, 8x16, 8x8, 8x4, 4x8, 4x4, etc. Motion estimation and motion compensation, the encoding end of the image needs to send the codeword identifying the division method of the image block to the decoding end of the image, so that the decoding end of the image can know the division method of the image encoding end, and according to the division method and motion vector information, determine corresponding prediction block. In the existing video coding and decoding standards, these sub-image blocks are rectangular blocks of NXM (both N and M are integers greater than 0), and N and M have a multiple relationship.

Among them, the commonly used ways for an image block to be divided into sub-image blocks are: 2Nx2N division method, the image block only contains one sub-image block, that is, the image block is not divided into smaller sub-image blocks, as shown in Figure 1a; 2NxN division method, divide the image block into two sub-image blocks of equal size up and down, as shown in Figure 1b; Nx2N division method, divide the image block into two sub-image blocks of equal size on the left and right, as shown in Figure 1c; NxN division In this way, the image block is divided into four sub-image blocks of equal size, as shown in Fig. 1d. In each of the above division methods, N is any positive integer, and the above division methods are all symmetrical division methods.

In addition, the image block can also use an asymmetrical division method, as shown in Figure 2a to Figure 2d, wherein, the division method shown in Figure 2a and 2b divides an image block into two upper and lower rectangular sub-image blocks of unequal size; The division methods shown in 2c and 2d divide an image block into two left and right rectangular sub-image blocks of unequal size. Specifically, Fig. 2a shows a 2NxnU division method, where n=0.5N, among the two sub-image blocks divided by this division method, the upper sub-image block is 2Nx0.5N, and the lower sub-image block is 2Nx1.5N, Among them, U in 2NxnU means that the image dividing line moves relative to the vertical bisector of the image block, and 2NxnU means that the image dividing line moves n relative to the vertical bisector of the image block, where n=x*N, where x is greater than or Equal to 0 and less than or equal to 1; Figure 2b shows the use of 2NxnD division method, where n=0.5N, in the two sub-image blocks divided by this division method, the upper sub-image block is 2Nx1.5N, and the lower sub-image The block is 2Nx0.5N, where D in 2NxnD means that the image dividing line moves down relative to the vertical bisector of the image block, and 2NxnD means that the image dividing line moves down by n relative to the vertical bisector of the image block, where n=x* N, where x is greater than or equal to 0 and less than or equal to 1; Figure 2c shows the nLx2N division method, where n=0.5N, in the two sub-image blocks divided by this division method, the left sub-image block is 0.5Nx2N , where, L in nLx2N means that the image dividing line moves left relative to the vertical bisector of the image block, nLx2N means that the image dividing line moves left n relative to the vertical bisector of the image block, where n=x*N, x is greater than Or equal to 0 and less than or equal to 1, the sub-image block on the right is 1.5Nx2N; Figure 2d shows the nRx2N division method, where n=0.5N, among the two sub-image blocks divided by this division method, the left sub-image The block size is 1.5Nx2N, and the sub-image block on the right is 0.5Nx2N. The R in nRx2N means that the image dividing line moves to the right relative to the vertical bisector of the image block, and nRx2N means that the image dividing line moves right by n relative to the vertical bisector of the image block. , where n=x*N, x is greater than or equal to 0 and less than or equal to 1.

In the division method of the above-mentioned image block, the image block is divided into a plurality of sub-image blocks arranged in the vertical direction through the horizontal division line. At this time, the division direction adopted is the horizontal division direction. The method is collectively referred to as the horizontal division method; and the vertical division method is to divide the image block into multiple sub-image blocks arranged in the horizontal direction through the vertical division line, and the division direction adopted at this time is the vertical division direction. , nRx2N division methods are collectively referred to as the vertical division method; at the same time, the image block is divided into four sub-image blocks through the horizontal division line and the vertical division line, and the division direction adopted at this time is the horizontal and vertical division directions. vertical division. The horizontal division method and the vertical division method are called non-square division methods, and each divided sub-image block has a non-square structure, while the horizontal and vertical division methods are called a square division method, and each divided sub-image block has a square structure.

During the encoding process of the image block, it is necessary to query the prediction block of the divided sub-image block. Therefore, the above division method of the image block can also be referred to by the type of the prediction block, and the division method of the image block corresponds to the type of the prediction block.

In the image block division using a non-square division method, the division method can reflect the texture information of the area where the image block is located. When the image block is divided horizontally, the texture of the area where the image block is located tends to have the characteristics of horizontal texture. When When the image block is divided vertically, the texture of the area where the image block is located tends to have the characteristics of vertical texture. The efficiency of transformation coding can be further improved if the shape of the transformation block matching the image texture features is adopted. Specifically, when the image block is divided horizontally, the transformation block is in the shape of a horizontal strip to adapt to the transformation coding with the characteristics of horizontal texture. ; When the image block is divided vertically, the transformation block is in the shape of a vertical strip to adapt to the transformation coding with the feature of vertical texture. Therefore, when dividing the transformation block, a non-square division method can also be used to divide the transformation block into a non-square structure consistent with the sub-image blocks, so as to match the texture features of the image blocks and improve the coding efficiency of the image blocks.

Transform block division:

In video coding and decoding technology, you can use the transformation block (that is, the transformation matrix) to remove the correlation of the residual of the image block, that is, to remove the redundant information of the image block, in order to improve the coding efficiency. The transformation of the data block in the image block is usually Two-dimensional transformation is used, that is, the residual information of the data block is multiplied by an NXM transformation matrix and its transpose matrix at the encoding end, and the transformation coefficients are obtained after the multiplication. The above steps can be described using the following formula:

f=T'×C×T

Wherein, C represents the residual information of the data block, T and T' represent the transformation matrix and the transposition matrix of the transformation matrix, and f represents the transformation coefficient matrix obtained after the transformation of the residual information of the data block. Among them, the transformation matrix can be a discrete cosine transformation (Discrete Cosine Transform, DCT) matrix, an integer transformation (Integer Transform) matrix, a KL transformation (Karhunen Lòeve Transform, KLT) matrix, etc., wherein KLT can better consider image blocks or image Texture information for block residuals.

Performing the above processing on the residual information of the image block is equivalent to converting the residual information of the image block from the spatial domain to the frequency domain, and the transformation coefficient matrix obtained after processing is concentrated in the low-frequency area; After the above transformation, quantization, entropy coding and other processing are performed on the transformation coefficient matrix obtained after transformation, and the bit stream obtained by entropy coding is sent to the decoding end.

In order for the decoding end to know the type and size of the transformation matrix used by the encoding end, usually, the encoding end will send indication information indicating the transformation matrix used by the current image block to the decoding end, and the decoding end determines the transformation matrix used by the encoding end according to the above indication information. The transformation matrix, according to the characteristics of the transformation matrix (orthogonality of the transformation matrix, etc.), decodes the bit stream sent by the encoder to obtain the transformation coefficient matrix, and multiplies the transformation coefficient matrix with the transformation matrix and its transpose matrix, which can be recovered to obtain The residual information of the data block approximately consistent with the encoding end. The above steps can be described using the following formula:

C=T×f×T',

Wherein, C represents the residual information of the data block, T and T' represent the transformation matrix and the transposition matrix of the transformation matrix, and f represents the transformation coefficient matrix obtained by the decoding end.

Since the residuals of image blocks may have different distribution rules, using a transformation matrix of a certain size often cannot achieve a good transformation effect. Therefore, it is necessary to try to use different sizes of transformation blocks for the residuals of image blocks. Therefore, for A 2Nx2N image block can use a transformation matrix with a size of 2Nx2N, a transformation matrix with a size of NxN, or a transformation matrix with a size of 0.5Nx0.5N. Therefore, in order to effectively represent how an image block uses a transformation matrix of different sizes , you can use the tree identification method. When identifying the size of the transformation block used by the image block, the first layer in the code stream has an indicator bit for identifying whether the image block uses a transformation matrix with a size of 2Nx2N. If the image block uses a transformation matrix with a size of 2Nx2N (As shown in Figure 3a), the indicator bit is 0; if the image block does not use 2Nx2N transformation, the indicator bit is 1, indicating that the transformation matrix with a size of 2Nx2N needs to be further divided into four transformation matrices with a size of NxN , and use 4 bits in the second layer structure of the code stream to identify whether each transformation matrix with a size of NxN is further divided; if the image block uses the transformation structure shown in Figure 3b, all 4 bits are 0, indicating Each transformation matrix with a size of NxN will not be further divided; when the transformation structure shown in Figure 3c is selected, 2 of the 4 bits are 0, 2 bits are 1, and 2 bits are 0. The transformation matrix of size NxN in the lower left and upper right is no longer divided; 2 bits of 1 indicate that the transformation matrix of size NxN in the upper left and lower right needs to be further divided to obtain a transformation matrix with a size of 0.5Nx0.5N; then In the third layer structure of the code stream, 4 bits are used to indicate whether the transformation matrix with a size of 0.5Nx0.5N on the upper left needs to be further divided, and 4 bits are used to indicate whether the transformation matrix with a size of 0.5Nx0.5N to the lower right needs to be transformed The matrix is further divided. If the image block uses the transformation structure shown in FIG. 3c, the above 4+4 bits are all 0, indicating that no further division will be made. Through the above layer-by-layer identification in the code stream, the transformation size used by the image block and the sub-image block can be effectively and flexibly indicated.

It can be seen that when transforming the residual of the image block, the transform block needs to be divided to obtain the size of the transform block used by the image block, obtain the best transform effect, and eliminate redundant information of the image block. Provides coding efficiency for image blocks.

When dividing the transformation block, the transformation block can be divided into a size equal to or smaller than the image block, and in the encoding and decoding process of the transformation block, the number of division layers allowed by the transformation block is usually preset, and the preset The minimum value of the size of the transformation block, where the number of division layers allowed by the transformation block refers to the maximum number of division layers that can be used by the transformation block. The initial division size of the block is 2Nx2N, the transformation block can be divided from the 0th layer to the 1st layer, and the size of the transformation block is changed from 2Nx2N to NxN. Alternatively, the image coding device may also write indication information identifying the maximum number of divisional layers that can be used in the code stream, so as to notify the image decoding device of the maximum number of divisional layers that can be used, for example, in the image coding device and the image decoding device in advance The minimum transformation block size is set to 0.5N. If the size of the transformation block is NxN, when the transformation block is divided to 0.5Nx0.5N, the transformation block will not be further divided.

The above two methods can also be used in combination. For example, the image encoding device and the image decoding device preset that a maximum of three layers can be used, and the minimum value of the preset transform block size is 0.5N. If the size of the transform block initially divided is 2Nx2N, the transform block can be divided from layer 0 to layer 2, and its size is divided from 2Nx2N to NxN and further divided into 0.5Nx0.5N. If the initial division size of the transformation block is NxN, the transformation block can be divided from layer 0 to layer 1, and its size is transformed from NxN to 0.5Nx0.5N. At this time, the size of the transformation block has reached the minimum size of the preset transformation block , at this time the transform block is no longer divided.

In practical applications, the division of the transformation block can be divided by quadtree or binary tree division. The quadtree division means that the transformation block is divided into four, and the divided The size of the transformation block is the same, that is, the width of all transformation blocks after division is equal, and the height of all transformation blocks after division is equal; the binary tree division method means that the transformation block is divided into two, and the size of each transformation block after division same.

In addition, in order to match the texture characteristics of the image block, when dividing the transformation block, the same division method as the image block can also be adopted, that is, the transformation block is divided in a non-square division method. However, the existing transformation block In the case of non-square division, the size of both sides of the transformation block needs to be equal to the minimum value of the size of the preset transformation block before stopping the division. For example, when the transformation block of 2Mx2M is divided into non-square division, it is divided from 2Mx2M to 0.5Mx2M, and When dividing from 0.25MxM to 0.25Mx0.25M, assuming that the minimum size of the preset transform block is 0.25M, the 0.25MxM transform block will continue to be divided into 0.25Mx0.25M. The problem with this division method is that the shape of the transformation block obtained by dividing the transformation block along the side not equal to the minimum size, that is, the aspect ratio of the transformation block, is inconsistent with the shape of the transformation block before division. This inconsistency will affect the coding efficiency of the transformation block, and will cause the transformation block to have three division directions at the same time in the non-square division: the horizontal division direction (the transformation block is divided from 2Mx2M to 0.5Mx2M), the horizontal and vertical division directions (the transformation block Divided by 0.5Mx2M into 0.25MxM) and vertical division direction (the transformation block is divided into 0.25Mx0.25M by 0.25MxM), which will lead to an increase in the logical complexity of the division, and the encoding end needs to try the encoding of the 0.25Mx0.25M transformation block Efficiency will also increase the complexity of the encoding side. In this embodiment, the same division method as that of the image block can be used when dividing the transform block, and a quadtree method of dividing one into four can be used for division.

In the embodiment of the present invention, when the transformation block is divided by a non-square division method, as long as the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block, the division of the transformation block is stopped, so as to improve the efficiency of the transformation block. Coding efficiency. The division of transform blocks will be described below with specific embodiments.

FIG. 4 is a schematic flowchart of a transform block division method provided by Embodiment 1 of the present invention. As shown in Figure 4, the method of this embodiment may include the following steps:

Step 101. Obtain the minimum value of the size of the preset transformation block;

Step 102. When performing non-square division of the transformation block, if the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block, stop dividing the transformation block;

Among them, the minimum value of the size of the preset transformation block is the minimum value of the width or height of the transformation block, or the minimum value of the average value of the sum of the width and height of the transformation block; non-square division refers to dividing the image block or transformation block Divide into different width and height.

This embodiment can be applied to image encoding and decoding processing, and the transformation block can be divided to obtain the size of the transformation block that satisfies the transformation processing of the residual of the image block. Specifically, when the image block is divided into non-square, As long as the width or height of the transformation block is equal to the minimum size of the preset transformation block, the division of the transformation block will stop. In this way, the width and height of the divided transformation blocks are all consistent in shape, that is, the ratio of width to height is consistent, and the image block The coding efficiency will be improved.

To sum up, the transformation block division method provided by the embodiment of the present invention, when performing non-square division on the transformation block, as long as one of the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block, the transformation block is stopped. The division can make the shape of each divided transform block consistent, and improve the transform coding efficiency of the image block.

FIG. 5 is a schematic flowchart of a transform block division method provided by Embodiment 2 of the present invention. As shown in FIG. 5, when this embodiment divides the transform block, the following steps may be included:

Step 201, judging whether to use non-square division for the transform block, if yes, execute step 203, otherwise, execute step 202;

Step 202: Divide the transformation block by using a square division method until the size of the transformation block is equal to the minimum size of the preset transformation block, stop dividing and end;

Step 203: Perform non-square division on the transform block, and judge whether one of the width or height of the divided transform block is equal to the minimum size of the preset transform block, if yes, stop dividing the transform block, and end, otherwise, Step 203 is continued until one of the width or height of the divided transform block is equal to the minimum size of the preset transform block.

Those skilled in the art can understand that the initial size of the transformation block is square, that is, the width and height are equal. When the transformation block is divided into non-square, it is divided from square to non-square. At this time, the width of the initial transformation block will be divided It is a quarter of the original, or the height will be divided into a quarter of the original, therefore, the prerequisite for partitioning from square to non-square is that the initial size of the transform block is at least the minimum value of the size of the preset transform block 4 times of , that is, only when the width or height of the transform block is at least 4 times the minimum value of the size of the preset transform block, the transform block is divided into a non-square shape, otherwise, the transform block is divided into a square shape.

Specifically, assuming that the size of the image block is 2Mx2M, the maximum value of the size of the preset transform block is 2M, the minimum value of the size of the preset transform block is 0.5M, and the initial value of the size of the transform block is equal to the size of the image block, transform The number of division layers allowed to be divided into blocks is 3 layers, and the division method of image blocks is Nx2N. Since the initial value of the transformation block is 2Mx2M, and 2M is 4 times the minimum value of 0.5M for the size of the preset transformation block, the transformation block can be used The non-square division method consistent with the image block, that is, the Nx2N horizontal division method is used to perform non-square division on the transform block. And when the initial size of the transform block is MxM, the minimum size of the preset transform block is 0.5M, since the size of the transform block is twice the minimum size of the preset transform block, then the transform block is square Divide, that is, divide the MxM transform block into 0.5Mx0.5M transform blocks.

In practical applications, since the maximum size of the transformation block corresponding to the image block is smaller than or equal to the size of the image block, and the maximum size of the preset transformation block may be smaller than the size of the image block, therefore, the maximum size of the transformation block corresponding to the image block The size may be equal to the size of the image block or the maximum size of a preset transform block. Therefore, when judging whether to divide the transformation block into a non-square shape, it is also necessary to judge the relationship between the size of the transformation block and the maximum size of the preset image block, so as to determine the division method of the transformation block. Specifically, when the image block is divided horizontally, the width of the transformation block is equal to the height of the transformation block, and the average value of the sum of the width and height of the transformation block is less than or equal to the maximum size of the preset transformation block, the horizontal division method is adopted , divide the transformation block so that the width of the transformed transformation block after division is equal to the width of the transformation block before division, and the height of the transformation block after division is smaller than the height of the transformation block before division; when the image block is divided vertically, the width of the transformation block is equal to The height of the transformation block, and the average value of the sum of the width and height of the transformation block is less than the maximum value of the size of the preset transformation block, the vertical division method is used to divide the transformation block, so that the width of the divided transformation block is smaller than the division The height of the previous transformation block, the height of the transformed transformation block after division is equal to the height of the transformation block before division; when the image block is divided horizontally or vertically, the width and height of the transformation block are different, and the sum of the width and height of the transformation block is When the average value is greater than the maximum size of the preset transformation block, horizontal division or vertical division is adopted, so that the width of the divided transformation block is smaller than the width of the transformation block before division, and the height of the divided transformation block is smaller than that of the transformation block before division. high. In addition, a square division manner may be used to divide the transform block.

When the image block division method is horizontal division, the width of the transformation block is equal to the height of the transformation block before division, and the average value of the width and height of the transformation block before division is less than or equal to the preset maximum size of the transformation block, The divided transformation block adopts non-square transformation, and the width of the non-square transformation is equal to the width of the transformation block before the division, and the height of the non-square transformation is smaller than the height of the transformation block before the division ;

When the image block division method is vertical division, the width of the transformation block before division is equal to the height of the transformation block before division, and the average value of the width and height of the transformation block before division is less than or equal to the preset maximum size of the transformation block , the divided transformation block adopts non-square transformation, and the height of the non-square transformation is equal to the height of the transformation block before the division, and the width of the non-square transformation is smaller than the width of the transformation block before the division ;

When the image block division method is horizontal division method or vertical division method, the width of the transformation block before division is not equal to the height of the transformation block before division, and the average value of the width and height of the transformation block before division is greater than the preset transformation block At the maximum size, the transform block adopts non-square transform, and the height of the non-square transform is smaller than the height of the transform block before division, and the width of the non-square transform is smaller than the width of the transform block before division .

In the above-mentioned embodiments of the present invention, when performing non-square division on the transformation block, it may also be determined whether to stop dividing the transformation block in combination with the preset number of division layers allowed for division of the transformation block. Specifically, when dividing the transformation block in this embodiment, the following steps are further included: obtaining the number of division layers allowed for the transformation block, wherein, performing non-square division on the transformation block, and when the width or height of the transformation block is equal to the preset When the size of the transform block is at the minimum value, stopping the division of the transform block can be specifically: performing non-square division on the transform block, and when the number of division layers of the transformation block is less than the preset number of division layers, and the width or height of the transformation block is equal to When the minimum value of the size of the transform block is preset, the division of the transform block is stopped.

Suppose the size of the image block is 2Mx2M, the maximum size of the preset transformation block is M, the minimum value of the preset transformation block size is 0.25M, the initial value of the size of the transformation block is equal to the size of the image block, and the transformation block allows division The number of divided layers is 4, and the image block division method is Nx2N. Since the initial value of the transformation block is 2Mx2M, its size is larger than the maximum size of the preset transformation block, so the size of the transformation block is divided from 2Mx2M to MxM, and the number of division layers is changed from layer 0 to layer 1; due to the preset transformation The minimum size of the block is 0.25M, and the transformation block can continue to be divided from the first layer to the second layer, and its size changes from MxM to 0.25MxM, because the width of the transformation block is equal to the minimum value of the size of the preset transformation block 0.25 M, at this time, the transform block is no longer divided.

FIG. 6 is a schematic flowchart of a transform block division method provided by Embodiment 3 of the present invention. Specifically, as shown in Figure 6, the method of this embodiment may include the following steps:

Step 301, obtain the maximum value of the size of the image block, the division method of the image block, and the size of the preset transformation block, the size of the image block is the average value of the width and height of the image block, and the size of the preset transformation block The maximum value of is the maximum value of the width or height of the transform block, or the average value of the sum of the width and height of the transform block;

Step 302: Obtain a first parameter according to the size of the image block and the maximum value of the size of the preset transformation block, the first parameter is used to represent the size of the largest transformation block corresponding to the image block, and the size of the transformation block The size is the average of the width and height of the transformed block;

Step 303: Obtain a second parameter according to the division method of the image block, the first parameter, and the minimum size of the preset transform block, and the second parameter is used to represent the smallest transform block corresponding to the image block Whether the size of is greater than the minimum value of the size of the preset transform block;

Step 304, according to the second parameter, judge whether to perform non-square division on the transform block, if yes, execute step 306, otherwise, execute step 305;

Step 305: Divide the transformation block by using a square division method until the size of the transformation block is equal to the minimum size of the preset transformation block, stop dividing, and end;

Step 306: Perform non-square division on the transform block, and judge whether one of the width or height of the divided transform block is equal to the minimum size of the preset transform block, if yes, stop dividing the transform block, and end, otherwise, Continue to execute step 304 until one of the width or height of the divided transform block is equal to the minimum size of the preset transform block.

In this embodiment, in the above step 302, according to the size of the image block and the maximum value of the size of the preset transformation block, obtaining the first parameter includes: when the size of the image block is larger than the size of the preset transformation block When the maximum value, the first parameter is equal to the maximum value of the size of the preset transformation block; when the size of the image block is smaller than the maximum value of the size of the preset transformation block, the first parameter is equal to the maximum value of the size of the preset transformation block The size of the image block; when the size of the image block is equal to the maximum value of the size of the preset transform block, the first parameter is equal to the size of the image block.

In this embodiment, the size of the image block, the size of the transformation block, the maximum value of the size of the preset transformation block, and the minimum value of the size of the preset transformation block are all represented by logarithms with base 2, wherein the above step 303 In the above, according to the division method of the image block, the first parameter and the minimum value of the size of the preset transformation block, obtaining the second parameter includes: when the division method of the image block is non-square division, and the When the value of the first parameter is greater than the minimum value of the size of the preset transform block plus 1, the value of the second parameter is set to 1; otherwise, the value of the second parameter is set to 0.

In this embodiment, in the above step 304, according to the second parameter, judging whether to perform non-square division on the transform block includes: when the value of the second parameter is 1, judging whether to use a non-square partition on the transform block Square division, otherwise, adopt square division for the transformation block; wherein, the square division refers to a division method of dividing the image block or the transformation block into different widths and heights.

The principle and implementation of the embodiment of the present invention will be described in more detail below by taking the process of dividing the size of a transform block of an image block with a size of 32x32 as an example.

Suppose the size of the image block is 32x32, the division method of the image block is the vertical division method, that is, the division method of the image block is one of Nx2N, nLNx2N, nRx2N, the maximum size of the preset transformation block is 32, and the preset transformation block The minimum value of the size is 4, and the number of division layers allowed by the preset transform block is 4 layers. Among them, the size of the image block, the size of the transformation block, and the maximum and minimum values of the size of the preset transformation block are expressed by logarithms with base 2. Specifically, the size of the image block is expressed by log2CbSize, and the size of the image block The relationship with log2CbSize can be expressed as: the size of the image block=1<<log2CbSize; the width and height of the transformation block are represented by the parameters log2TrafoHeight and log2TrafoWidth, and the relationship between the height of the transformation block and log2TrafoHeight can be expressed as: the height of the transformation block=1< <log2TrafoHeight; the relationship between the width of the transformation block and log2TrafoWidth can be expressed as: the width of the transformation block=1<<log2TrafoWidth; the maximum value of the size of the preset transformation block is represented by Log2MaxTrafoSize, and the relationship between the maximum size of the transformation block and Log2MaxTrafoSize can be It is expressed as: the maximum value of the size of the transformation block=1<<Log2MaxTrafoSize; the minimum value of the size of the preset transformation block is represented by Log2MinTrafoSize, and the relationship between the minimum value of the size of the transformation block and Log2MinTrafoSize can be expressed as: the minimum size of the transformation block Value=1<<Log2MinTrafoSize, therefore, in this example, the initial values of log2CbSize, log2TrafoHeight and log2TrafoWidth are all 5, Log2MaxTrafoSize=5, Log2MinTrafoSize=2.

In addition, the size of the transformation block can also be represented by log2TrafoSize, which is used to represent the average width and height of the transformation block. Therefore, the relationship between log2TrafoSize, log2TrafoHeight and log2TrafoWidth can be expressed as: log2TrafoSize=(log2TrafoHeight+log2TrafoHeight)>>1, that is, log2TrafoSize It is the average of log2TrafoHeight and log2TrafoWidth.

In the calculation operation of each size expressed by the index in this example, "<<" represents the left shift operation, 1<<log2TrafoHeight is equivalent to 2log2TrafoHeight operation; 1<<log2TrafoWidth is equivalent to 2log2TrafoWidth operation; 1<<log2TrafoSize is equivalent to 2log2TrafoSize operation; ">>" represents a right shift operation, (log2TrafoHeight+log2TrafoHeight)>>1 is equivalent to (log2TrafoHeight+log2TrafoHeight)/2 operation.

In this example, when the transform block is divided into smaller sub-transform blocks, the change of the transform block size can be reflected by adding or subtracting the values of the parameters log2TrafoHeight, log2TrafoWidth and log2TrafoSize. For example, when the size of the current transformation block is 16x16, the value of log2TrafoHeight is 4, the value of log2TrafoWidth is 4, and the value of log2TrafoSize is 4. When the transformation block is divided into 16x4 sub-transformation blocks, the size of the divided transformation block becomes 16x4, at this time, the value of log2TrafoWidth remains unchanged at 4, the value of log2TrafoHeight becomes 2, and the value of log2TrafoSize becomes 3.

In this example, the division of the transformation block is divided into four. When the transformation block is divided into non-square, the length of one side of the divided transformation block will be four times the length of the other side. Therefore, when the When the transformation block is divided into non-square, when the width of the divided transformation block is greater than the height, the following relationship will exist: log2TrafoWidth=log2TrafoHeight+2, when the width of the divided transformation block is smaller than the height, log2TrafoHeight=log2TrafoWidth+2.

Since the size of the transformation block is expressed in exponential form, the size of the transformation block log2TrafoSize is the average value of the width (log2TrafoWidth) and height (log2TrafoHeight), that is, log2TrafoSize=(log2TrafoHeight+log2TrafoHeight)>>1. Therefore, when the width or height of the transform block is equal to the minimum size of the preset transform block, log2TrafoSize=Log2MinTrafoSize+1.

Therefore, in the process of image encoding and decoding, when the transformation block is divided into non-square, and the value of log2TrafoSize is equal to Log2MinTrafoSize+1, the division of the transformation block will be stopped; and in the process of image encoding and decoding, it is possible to divide the transformation block Carry out square division, and in the square division, the value of log2TrafoSize needs to be equal to Log2MinTrafoSize, the transformation block will stop dividing, so the variable Log2MinTrafoSizePlus1 can be introduced in the process of encoding and decoding to determine whether the transformation block adopts non-square division, when Log2MinTrafoSizePlus1 is equal to 1 When , the transformation block can be divided into non-square parts. In the codec system, there are restrictions on whether the transformation block can be divided into non-square parts. For example, when the size of the transformation block is a certain size, such as 8x8, and the minimum size of the transformation block is 4 , then non-square transformation can no longer be performed. Therefore, when the limit is satisfied, when the transformation block needs to be further divided, non-square division can be used; when Log2MinTrafoSizePlus1 is equal to 0, non-square division is not allowed for transformation, and square division is used. , and no matter whether the transform block is divided into non-square or square, the transform block will stop dividing when log2TrafoSize=Log2MinTrafoSize+Log2MinTrafoSizePlus1. Wherein, the Log2MinTrafoSizePlus1 is the above-mentioned second parameter.

In this example, when the transform block is divided, the transform block will not be divided until the width or height of the transform block is at least 4 times the minimum size of the preset transform block. In the encoding and decoding process of the image block, the maximum value of the size of the transformation block is also preset. Therefore, when the size of the transformation block is larger than the maximum size of the preset transformation block, the transformation block needs to be divided. into smaller transformed blocks.

Since the maximum size of the transformation block used by the image block is equal to the size of the image block, before determining whether the transformation block adopts non-square division, it is also necessary to determine the maximum size of the transformation block corresponding to the image block, that is, to determine the transformation using non-square division The initial division size of the block. Let the initial division size of the transformation block be Log2MaxTrafoSizeInCu, since the initial value of the transformation block is equal to the size log2CbSize of the image block, when log2CbSize is greater than the maximum value Log2MaxTrafoSize of the preset transformation block, the value of Log2MaxTrafoSizeInCu is equal to Log2MaxTrafoSize; otherwise, log2CbSize is equal to or When it is smaller than the maximum value Log2MaxTrafoSize of the size of the preset transformation block, the value of Log2MaxTrafoSizeInCu is equal to log2CbSize, which can be expressed in mathematical form as follows:

Log2MaxTrafoSizeInCu=log2CbSize>Log2MaxTrafoSize? Log2MaxTrafoSize:log2CbSize.

It can be seen that the initial size of the transformation block is at least 4 times the minimum size of the preset transformation block, which can be expressed as Log2MaxTrafoSizeInCu>(Log2MinTrafoSize+1), that is, the value of Log2MaxTrafoSizeInCu is at least (Log2MinTrafoSize+1), because Log2MaxTrafoSizeInCu, Log2MinTrafoSize, etc. The parameters are all expressed in exponential form, it can be seen that the initial size of the transformation block at this time is at least 4 times the minimum value of the size of the preset transformation block.

The precondition for the non-square division of the transform block is that the image block adopts a horizontal division mode or a vertical division mode. In the present invention, in addition to the horizontal division method (2NxN, 2NxnU, 2NxnD) and the vertical division method (Nx2N, nLx2N, nRx2N), the square division method of 2Nx2N and NxN can also be used, so let PART2Nx2N and PART NxN represent the image block respectively. 2Nx2N and NxN division methods, when the following conditions are met, the transformation block adopts non-square division (that is, the value of Log2MaxTrafoSizeInCu is 1), otherwise the transformation block does not adopt non-square division (that is, the value of Log2MaxTrafoSizeInCu is 0):

if(nsrqt_enabled_flag&&Log2MaxTrafoSizeInCu>(Log2MinTrafoSize+1)&&PartMode!=PART_2NX2N&&PartMode!=PART_NXN)

Among them, nsrqt enabled flag is a flag bit that allows the use of non-square division in the process of encoding and decoding.

When the size of the transformation block is greater than 4 times the minimum size of the preset transformation block (ie log2TrafoSize>(Log2MinTrafoSize+Log2MinTrafoSizePlus1)), the image encoding end needs to write the transformation block division parameters, and the decoding end needs to analyze the transformation block division parameters ; Otherwise (ie log2TrafoSize==(Log2MinTrafoSize+Log2MinTrafoSizePlus1)) the encoder does not write the division parameters of the transformation block, and the decoder does not decode the division parameters of the transformation block. The encoding and decoding of the transformation block division parameters by the encoding end and the decoding end will be described in detail in the following embodiments.

It can be seen from this example that, through the second parameter, it can be determined whether the transform block is divided into squares, and the size of the divided transform block can be determined. Those skilled in the art can understand that the second parameter is an intermediate variable used to facilitate image coding, and the second parameter can be obtained as required in practical applications, and is not limited to the method for obtaining the second parameter described above.

In the above-mentioned embodiments of the present invention, the division of the transformation block refers to the division of the brightness block of the image block. In practical applications, the chrominance block in the image block is half of the brightness block. Therefore, the chrominance block in the image block When the block is divided, the following steps are also included:

Obtain the size of the largest transform block of the chrominance block corresponding to the image block;

Whether the size of the transform block corresponding to the chroma block in the determined transform block exceeds the size of the largest transform block of the chroma block corresponding to the image block, and if so, the transform size corresponding to the chroma block in the divided transform block Reset to the largest transform block size of the chroma block corresponding to the image block.

Those skilled in the art can understand that the size of the largest transform block corresponding to the chrominance block of the above-mentioned image block means that the largest transform block corresponding to the image block is half the size of the largest transform block allowed to be used by the image block. When the size of is less than or equal to the maximum size of the preset transform block, the size of the largest transform block corresponding to the image block is the size of the image block, otherwise, it is equal to the maximum size of the preset transform block.

To facilitate the description of the division of chrominance blocks, the division of chrominance blocks during the encoding and decoding process of video in 4:2:0 format in the video encoding and decoding system will be described below. Wherein, the 4:2:0 format means that the size of the chrominance component in the video is half of the brightness component. For example, if the size of the video is 416x240, the size of the brightness in an image is 416x240, and the size of the chrominance is 208x120. Since video images are encoded in units of blocks, the size of a chroma block is always half the size of a luma block when encoding in the 4:2:0 format, for example, the size of a luma block is 32x32, and the size of a chroma block is 16x16 . In the above transform block encoding and decoding process, the transform block size of chroma and the transform block size of luma follow the same relationship, for example, when the transform block size of luma is 8x8, the transform block size of chroma is 4x4.

Since the minimum value of the size of the transform block is usually preset in the codec system, for example, the minimum value of the size of the preset transform block is 4, so when the size of the transform block of the chroma is halved according to the size of the transform block of the luma, it is possible It will cause the size of the chroma transformation block to be smaller than the minimum size of the preset transformation block. For example, when the size of the luma transformation block is 4x4, the size of the chroma transformation block is 2x2. At this time, the size of the chroma transformation block is already smaller than the preset size. Let the minimum value of the transform block size be 4. In this case, it is necessary to reset the size of the transform block of the chroma, and reset the size of the transform block of the chroma to be consistent with the size of the transform block of the luma, that is, reset the size to 4x4.

When the transformation block adopts non-square division, several additional cases will be added. Let the minimum value of the size of the default transform block be 4. It can be seen that when the transform block is divided into non-square, the corresponding minimum transform block size is 16x4 or 4x16. When the size of the luma transform block is 16x4 or 4x16, and the size of the chroma transform block is 8x2 or 2x8, the size of the chroma transform block needs to be reset. However, the resetting process also needs to consider the transform block size allowed by the chroma block in the current image block.

Specifically, when the image block size is 32x32, and the preset maximum transform block size is 32x32, the image block is divided horizontally. At this time, the maximum transform block size that can be used by the luma block is 32, and the corresponding transform block can be divided from 32x32 to 16x16 and further divided to 16x4. The maximum transform block size that can be used by a chroma block is 16. Since the transform block size of chroma is always halved by the size of luma transform block, the corresponding transform block can be divided from 16x16 to 16x4 and further divided to 8x2. Since 8x2 is already smaller than the minimum size of the preset transform block, the size of the transform block needs to be reset. Since the maximum transform block size that can be used by the chroma block is 16, the transform block size of the chroma can be reset to 16x4 at this time.

When the image block size is 16x16, and the preset maximum transform block size is 32x32, the image block is divided horizontally. At this time, the maximum transform block size that can be used by the luma block is 16, and the corresponding transform block can be divided from 16x16 to 16x4. The maximum transform block size that can be used by a chroma block is 8. Since the size of a chroma transform block is always halved by the size of a luma transform block, the corresponding transform block can be divided from 8x8 to 8x2. Since 8x2 is already smaller than the minimum size of the preset transform block, the size of the transform block needs to be reset. Since the maximum transform block size that can be used by the chroma block is 8, the size of the transform block of the chroma cannot be reset to 16x4 at this time, so the size of the chroma block can only be reset to 8x8.

To sum up, it can be seen that in the case of 4:2:0 format encoding, if the transformation block adopts a non-square division method, the following additional judgment steps exist for the size of the transformation block of chroma: determine whether the size of the transformation block has reached the minimum Transform block size; if the size of the transform block has reached the minimum transform block size, obtain the maximum transform block size corresponding to the current image block; judge whether its size will exceed the maximum corresponding to the current image block according to the transform block size of the chroma block Transform the block size, if it exceeds, reset its size to the preset value.

In this embodiment, when the transform block is divided, as long as one of the width or height of the transform block is equal to the minimum value of the size of the preset transform block, the division of the transform block is stopped. In the video codec system, according to the transform The relationship between the size of the block and the minimum value of the size of the preset transform block encodes or decodes the division parameters of the transform block. Different embodiments will be described below.

FIG. 7 is a schematic flowchart of a method for encoding transformation block division parameters provided by Embodiment 4 of the present invention. This embodiment can encode the division parameters of the transform block at the encoding end in the video codec system. Specifically, as shown in FIG. 7, this embodiment can include the following steps:

Step 401. Obtain the minimum value of the size of the preset transformation block;

Step 402, according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block, determine whether to encode the division parameters of the transform block;

The division parameter of the transform block is used to indicate whether to divide the transform block or not.

In this embodiment, the above-mentioned step 402 may specifically include: when the transformation block adopts non-square division, and the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block, judging that the transformation block does not need to be coded partition parameter, otherwise, the partition parameter of the coded transform block.

In this embodiment, the above step 402 may also include: judging whether to encode the division parameter of the transformation block according to the second parameter, wherein the second parameter is used to indicate whether the size of the smallest transformation block corresponding to the image block is larger than the predetermined Sets the minimum size of the transform block.

Among them, the second parameter can be obtained through the following steps:

Obtain the size of the image block, the division method of the image block, and the maximum value of the size of the preset transformation block;

According to the size of the image block and the maximum value of the size of the preset transformation block, a first parameter is obtained, and the first parameter is used to indicate the size of the largest transformation block corresponding to the image block;

The second parameter is obtained according to the division manner of the image block, the first parameter, and the minimum value of the size of the preset transformation block.

In this embodiment, according to the second parameter, the division parameters for judging whether to encode and transform the block include:

When the size of the transformation block is greater than the minimum value of the size of the preset transformation block plus the second parameter, the division parameter of the transformation block is encoded; otherwise, the division parameter of the transformation block does not need to be encoded.

The acquisition of the second parameter and the first parameter in this embodiment is the same as that in the embodiment of the transformation block division method of the present invention described above, and will not be repeated here.

In the codec system, the maximum value of the number of division layers that can be divided by the transformation block is usually set, that is, the preset number of division layers. Therefore, when encoding the division parameters of the transformation block, the following steps may also be included: obtaining the transformation The preset number of division layers allowed for the block to be divided; when the number of division layers of the transform block is equal to the preset number of division layers, it is determined that the division parameters of the transform block do not need to be coded. In the process of transform block encoding, as long as any condition of the size of the transform block or the number of division layers meets the above requirements, it is not necessary to encode the division parameters of the transformation block, that is, the transformation block does not need division parameters, which means that the transformation block does not need divided.

Correspondingly, the embodiment of the present invention also provides a decoding method of transform block division parameters.

FIG. 8 is a schematic flowchart of a decoding method for transform block division parameters provided by Embodiment 5 of the present invention. As shown in FIG. 8, the decoding method of the transform block in this embodiment may include the following steps:

Step 501. Obtain the minimum value of the size of a preset transform block;

Step 502, according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block, determine whether to decode the division parameter of the transform block;

The division parameter of the transform block is used to indicate whether to divide the transform block or not.

The decoding method in this embodiment is actually a process corresponding to the above encoding method. Specifically, in the above step 502, it is judged whether to decode the transform according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block. Block partitioning parameters can include:

When the transformation block adopts non-square transformation, and the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block, it is judged that the division parameter of the transformation block does not need to be decoded; otherwise, the division parameter of the transformation block is decoded.

In addition, in the actual decoding process, the above step 502 may specifically include: judging whether to decode the division parameter of the transformation block according to the second parameter, the second parameter is used to indicate whether the size of the smallest transformation block corresponding to the image block is larger than the predetermined Sets the minimum size of the transform block.

The above-mentioned second parameter can be obtained through the following steps: obtain the size of the image block, the division method of the image block, and the maximum value of the size of the preset transformation block; according to the size of the image block and the maximum value of the size of the preset transformation block, Obtain a first parameter, the first parameter is used to represent the size of the largest transform block corresponding to the image block; according to the division method of the image block, the first parameter and the minimum value of the size of the preset transform block, Get the second parameter. The judging whether to decode the division parameter of the transform block according to the second parameter includes: decoding the division parameter of the transform block when the size of the transform block is greater than the minimum value of the size of the preset transform block plus the second parameter.

In addition, the decoding method of this embodiment may also include:

Obtain the preset number of division layers allowed for the transformation block;

When the number of division layers of the transform block is equal to the preset number of division layers, it is determined that the division parameters of the transform block do not need to be decoded.

During the decoding process, when the number of division layers of the transform block has reached the preset number of division layers, the decoding of the division parameters of the transform block can be stopped.

Those of ordinary skill in the art can understand that all or part of the steps for realizing the above-mentioned method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the It includes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other various media that can store program codes.

FIG. 9 is a schematic structural diagram of an apparatus for dividing transform blocks according to Embodiment 6 of the present invention. As shown in FIG. 9, the apparatus for dividing transform blocks in this embodiment may include:

A size obtaining module 1, configured to obtain the minimum value of the size of the preset transformation block;

The transformation block division module 2 is used for performing non-square division on the transformation block, if the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block, then stop dividing the transformation block;

Wherein, the minimum value of the size of the preset transformation block is the minimum value of the width or height of the transformation block, or the minimum value of the average value of the sum of width and height; the non-square division refers to dividing the image block or the transformation block Divide into division methods ranging in width and height.

The apparatus for dividing transform blocks in this embodiment realizes the division of transform blocks based on the steps of the method for dividing transform blocks in the present invention. For the specific implementation process, refer to the description of the method embodiments of the present invention described above, which will not be repeated here.

FIG. 10 is a schematic structural diagram of an apparatus for dividing transform blocks provided by Embodiment 7 of the present invention. As shown in Figure 10, on the basis of the illustration shown in Figure 9 above, this embodiment may further include:

A partition judging module 3, configured to judge whether to perform non-square partition on the transform block.

As shown in Figure 10, the division judgment module 3 may specifically include:

A division method obtaining unit 31, configured to obtain the division method of the image block;

The first judging unit 32 is configured to: when the image block is divided horizontally, the width of the transformation block is equal to the height of the transformation block, and the average value of the sum of the width and height of the transformation block is less than or equal to the size of the preset transformation block When the maximum value, and the width or height of the transform block is at least 4 times the minimum value of the size of the preset transform block, it is judged that the transform block is divided into a non-square, so that the width of the divided transform block is equal to The width of the transformation block before division, and the height of the transformation block after division is smaller than the height of the transformation block before division;

The second judging unit 33 is used for when the image block is divided vertically, the width of the transformation block is equal to the height of the transformation block, and the average value of the sum of the width and height of the transformation block is smaller than the maximum value of the size of the preset transformation block , and the width or height of the transform block is at least 4 times the minimum size of the preset transform block, it is determined that the transform block is divided into a non-square shape, so that the width of the transformed block after division is smaller than that before division The height of the transformation block, the height of the transformed transformation block after division is equal to the height of the transformation block before division;

The third judging unit 34 is used for when the image block is divided horizontally or vertically, the width and height of the transformation block are not equal, and the average value of the sum of the width and height of the transformation block is greater than the size of the preset transformation block maximum value, and the width or height of the transform block is at least 4 times the minimum value of the size of the preset transform block, it is judged that the transform block is divided into a non-square shape, so that the width of the transformed transform block after division is less than The width of the transform block before division, and the height of the transform block after division is smaller than the height of the transform block before division.

FIG. 11 is a schematic structural diagram of an apparatus for dividing transform blocks provided by Embodiment 8 of the present invention. Different from the above-mentioned embodiment shown in FIG. 10, as shown in FIG. 11, in this embodiment, the division judgment module 3 specifically includes:

The first acquiring unit 35 is configured to acquire the size of the image block, the division method of the image block and the maximum value of the size of the preset transformation block, the size of the image block is the average value of the width and height of the image block, and the preset Let the maximum value of the size of the transformation block be the maximum value of the width and height of the transformation block, or the minimum value of the average value of the sum of width and height;

The first parameter obtaining unit 36 is configured to obtain a first parameter according to the size of the image block and the maximum value of the size of the preset transformation block, and the first parameter is used to represent the size of the largest transformation block corresponding to the image block , the size of the transform block is the average value of the width and height of the transform block;

The second parameter acquisition unit 37 is configured to obtain a second parameter according to the division method of the image block, the first parameter and the minimum value of the size of the preset transformation block, and the second parameter is used to represent the image whether the size of the smallest transform block corresponding to the block is greater than the minimum size of the preset transform block;

The division determination unit 38 is configured to determine whether to perform non-square division on the transform block according to the second parameter.

In this embodiment, the first parameter acquiring unit 36 is specifically configured to: when the size of the image block is greater than the maximum size of the preset transform block, the first parameter is equal to the size of the preset transform block the maximum value of the image block; when the size of the image block is smaller than the maximum value of the size of the preset transform block, the first parameter is equal to the size of the image block; and when the size of the image block is equal to the preset When the maximum value of the size of the transformation block is assumed, the first parameter is equal to the size of the image block.

In this embodiment, the size of the image block, the size of the transform block, the maximum value of the size of the preset transform block, and the minimum value of the size of the preset transform block are all represented by a logarithm with base 2; and each size is represented by an exponent When expressing, the above-mentioned second parameter acquisition unit 37 can be specifically used when the division method of the image block is to adopt non-square division, and the value of the first parameter is greater than the minimum value of the size of the preset transformation block plus 1 , set the value of the second parameter to 1, otherwise set the value of the second parameter to 0; the above-mentioned division judgment unit 38 can be specifically used to determine whether the second parameter is allowed when the value of the second parameter is 1 Using non-square partitioning for the transform block, otherwise, using square partitioning for the transform block;

Wherein, the square division refers to a division method of dividing an image block or a transformation block into widths and heights.

FIG. 12 is a schematic structural diagram of an apparatus for dividing transform blocks according to Embodiment 9 of the present invention. On the basis of the above embodiments shown in FIG. 9 , FIG. 10 or FIG. 11 , as shown in FIG. 12 , this embodiment may further include:

A division parameter acquisition module 4, configured to acquire the preset number of division layers allowed to be divided by the transform block;

The transformation block division module 2 can specifically be used to perform non-square division on the transformation block, and the number of division layers of the transformation block is less than the preset number of division layers, and the width or height of the transformation block is equal to the preset transformation block When the minimum value of the size of , stop dividing the transform block.

In addition, as shown in Figure 12, this embodiment may also include:

Chroma transformation block size acquisition module 5, used to obtain the size of the largest transformation block of the chrominance block corresponding to the image block;

The chroma transform block reset module 6 is used to judge whether the size of the transform block corresponding to the chroma block in the divided transform block exceeds the size of the largest transform block of the chroma block corresponding to the image block, and if so, the The transform size corresponding to the chroma block in the divided transform block is reset to the size of the largest transform block of the chroma block corresponding to the image block.

For the specific implementation process of each embodiment of the transform block division device of the present invention, refer to the description of the embodiment of the transform block division method of the present invention above, and details are not repeated here.

FIG. 13 is a schematic structural diagram of an encoding device for transforming block division parameters provided by Embodiment 10 of the present invention. As shown in Figure 13, the encoding device of this embodiment includes:

A size acquiring module 10, configured to acquire a minimum value of the size of a preset transform block;

A parameter encoding module 20, configured to determine whether to encode the division parameters of the transform block according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block;

The division parameter of the transform block is used to indicate whether to divide the transform block or not.

In this embodiment, the above-mentioned parameter encoding module 20 can specifically be used to determine that encoding is not required when the transformation block is divided into non-square, and the width or height of the transformation block is equal to the minimum value of the size of the preset transformation block. The partition parameter of the transform block, otherwise, the partition parameter of the encoded transform block.

FIG. 14 is a schematic structural diagram of an encoding device for transforming block division parameters provided by Embodiment 11 of the present invention. In this embodiment, the parameter encoding module 20 may specifically be configured to determine whether to encode the division parameter of the transform block according to the second parameter. Specifically, as shown in Figure 14, this embodiment may also include:

The second acquiring unit 210 is configured to acquire the size of the image block, the division method of the image block and the maximum value of the size of the preset transformation block;

The first parameter obtaining unit 211 is configured to obtain the first parameter according to the size of the image block and the maximum value of the size of the preset transformation block;

The second parameter obtaining unit 212 is configured to obtain the second parameter according to the division method of the image block, the first parameter and the minimum value of the size of the preset transformation block.

In this embodiment, the second parameter is used to indicate whether the size of the smallest transform block corresponding to the image block is greater than the minimum size of the preset transform block; the first parameter is used to indicate whether the size of the smallest transform block corresponding to the image block The size of the largest transform block.

In this embodiment, the above-mentioned parameter encoding module 20 can specifically be used to encode the division parameters of the transform block when the size of the transform block is greater than the minimum value of the size of the preset transform block plus the second parameter; otherwise, not The partition parameters of the coded transform block are required.

FIG. 15 is a schematic structural diagram of an encoding device for transforming block division parameters provided by Embodiment 12 of the present invention. On the basis of the above embodiment shown in FIG. 13 or FIG. 14, as shown in FIG. 14, this embodiment may further include:

A division parameter acquisition module 30, configured to acquire the preset number of division layers allowed for division of the transform block;

The parameter encoding module 20 is specifically configured to determine that it is not necessary to encode the division parameters of the transformation block when the number of division layers of the transformation block is equal to the preset number of division levels.

For the specific implementation process of the device for encoding transform block division parameters of the present invention, refer to the embodiment of the encoding method for transform block division parameters of the present invention described above, which will not be repeated here.

FIG. 16 is a schematic structural diagram of a decoding apparatus for transforming block division parameters provided by Embodiment 13 of the present invention. As shown in Figure 16, the decoding device in this embodiment may include:

A size acquiring module 40, configured to acquire the minimum value of the size of the preset transform block;

The parameter decoding module 50 is configured to judge whether to decode the division parameter of the transform block according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block;

The division parameter of the transform block is used to indicate whether to divide the transform block or not.

In this embodiment, the above-mentioned parameter decoding module 50 can specifically be used to determine that no decoding transformation is required when the transformation block adopts non-square transformation, and the width or height of the transformation block is equal to the minimum value of the preset transformation block size. The partition parameter of the block, otherwise, the partition parameter of the decoded transformed block.

FIG. 17 is a schematic structural diagram of a decoding apparatus for transforming block division parameters provided by Embodiment 14 of the present invention. Different from the technical solution of the above-mentioned embodiment shown in FIG. 16 , in this embodiment, the parameter decoding module 50 is specifically configured to judge whether to decode the division parameter of the transformation block according to the second parameter. Specifically, as shown in Figure 17, this embodiment may also include:

The second obtaining unit 510 is configured to obtain the size of the image block, the division method of the image block and the maximum value of the size of the preset transformation block;

The first parameter obtaining unit 511 is configured to obtain the first parameter according to the size of the image block and the maximum value of the size of the preset transformation block;

The second parameter obtaining unit 512 is configured to obtain the second parameter according to the division method of the image block, the first parameter and the minimum size of the preset transformation block.

In this embodiment, the above-mentioned second parameter is used to indicate whether the size of the smallest transform block corresponding to the image block is greater than the minimum size of the preset transform block; the above-mentioned first parameter is used to indicate whether the size of the image block corresponds to The size of the largest transform block. Wherein, the parameter decoding module 50 is specifically configured to decode the division parameter of the transform block when the size of the transform block is greater than the minimum value of the size of the preset transform block plus the second parameter.

FIG. 18 is a schematic structural diagram of a decoding apparatus for transforming block division parameters provided by Embodiment 15 of the present invention. On the basis of the technical solution of the above embodiment shown in Figure 16 or Figure 17, as shown in Figure 18, this embodiment may further include:

A division parameter acquisition module 60, configured to acquire the preset number of division layers allowed for division of the transform block;

The parameter decoding module 50 can be specifically configured to determine that the division parameters of the transformation block do not need to be decoded when the number of division layers of the transformation block is equal to the preset number of division levels.

For the specific implementation process of the decoding device for transforming block division parameters of the present invention, refer to the above-mentioned embodiment of the decoding method for transform block division parameters of the present invention, which will not be repeated here.

FIG. 19 is a schematic structural diagram of an image encoding and decoding system provided by Embodiment 16 of the present invention. As shown in Figure 19, the image encoding and decoding system of this embodiment includes:

The encoding device 100 for transform block division parameters is configured to determine whether to encode the division parameters of the transform block according to the relationship between the size of the transform block and the minimum value of the size of the preset transform block;

The decoding device 200 of the transformation block division parameter is used to determine whether to decode the division parameter of the transformation block according to the relationship between the size of the transformation block and the minimum value of the size of the preset transformation block;

Wherein, the division parameter of the transform block is used to indicate whether to divide the transform block or not to divide

In this embodiment, the encoding device 100 for transforming block division parameters can specifically adopt the encoding device for transforming block division parameters provided by the above-mentioned embodiments of the present invention, and can refer to the description of the embodiment shown in FIG. 13 , FIG. 14 or FIG. 15 for details; The block division parameter decoding device 200 can specifically adopt the above-mentioned decoding device for transforming block division parameters provided by the embodiment of the present invention, and for details, refer to the description of the embodiment shown in FIG. 16 , FIG. 17 or FIG. 18 , which will not be repeated here.

Those skilled in the art can understand that other processing processes in the process of encoding images by the image encoding and decoding system in this embodiment, such as decomposing image blocks, quantizing image blocks, and entropy encoding, are similar to existing image encoding and decoding systems. The process is the same or similar, and will not be repeated here.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (40)

1. a kind of transform block division methods, it is characterised in that including：

Obtain the minimum value of the size of default transform block；

To transform block when carrying out non-square division, if the size in the default transform block wide or high of the transform block Minimum value, then stop dividing the transform block；

Wherein, it refers to that image block or transform block are divided into wide and division methods not etc. high that the non-square is divided；

Before non-square division is carried out to transform block, also include：Judge whether to carry out non-square division to the transform block；

It is described to judge whether that non-square division is carried out to the transform block to be included：

Obtain the dividing mode of image block；

When image block uses horizontal division, the width of the transform block is equal to the height of transform block, the sum wide and high of the transform block Average value be less than or equal to default transform block size maximum, and the transform block it is wide or high be at least it is described default When the minimum value of the size of transform block adds 2, judge to divide the transform block using non-square so that transform block after division Width is equal to the width of transform block before dividing, the height of the height less than transform block before dividing of the transform block after division；

When image block uses vertical division, the width of the transform block is equal to the height of transform block, the sum wide and high of the transform block Average value be less than default transform block size maximum, and the wide or high of the transform block is at least the default transform block The minimum value of size when adding 2, judge to divide the transform block using non-square so that the width of the transform block after division is less than The width of transform block before dividing, the height of the high transform block before dividing of the transform block after division；

When image block uses horizontal division or vertical division, wide and high, the wide and height of the transform block of the transform block The average value of sum is more than the maximum of the size of default transform block, and the wide or high of the transform block is at least the default change Change the minimum value of the size of block plus when 2, judge to divide the transform block using non-square so that the width of the transform block after division Less than the width of transform block before dividing, the height of the height less than transform block before dividing of the transform block after division；

Wherein, the size of the size of transform block and default transform block with 2 for the logarithm of radix is represented.

2. transform block division methods according to claim 1, it is characterised in that the non-square is divided to be included：2NxN draws Divide method, or 2NxnU division methods, or 2NxnD division methods, or Nx2N division methods, or nLx2N division methods, or nRx2N Division methods.

3. transform block division methods according to claim 1, it is characterised in that also include：

Obtain the default division number of plies that transform block allows to divide；

It is described when carrying out non-square to transform block and divide, if the size in default transform block wide or high of the transform block Minimum value, then stop carrying out division to the transform block including：

Carry out non-square division to transform block, and the division number of plies in the transform block divides the number of plies, and the change less than default During the minimum value of the size in default transform block wide or high for changing block, stop the division to the transform block.

4. transform block division methods according to claim 1, it is characterised in that also include：

Obtain the size of the maximum transform block of the corresponding chrominance block of image block；

Whether the size of the corresponding transform block of chrominance block exceedes the corresponding chrominance block of described image block most in the transform block of judgement The size of big transform block, is that the size of the corresponding transform block of the chrominance block is reset into the corresponding chrominance block of described image block Maximum transform block size.

5. a kind of transform block division methods, it is characterised in that including：

Obtain the minimum value of the size of default transform block；

To transform block when carrying out non-square division, if the size in the default transform block wide or high of the transform block Minimum value, then stop dividing the transform block；

Wherein, it refers to that image block or transform block are divided into wide and division methods not etc. high that the non-square is divided；

Before non-square division is carried out to transform block, also include：Judge whether to carry out non-square division to the transform block；

It is described to judge whether that non-square division is carried out to the transform block to be included：

Obtain the maximum of the size of the size, the dividing mode of image block and default transform block of image block, described image block Size be the average value wide and high of image block, the maximum of the size of the default transform block is the wide and high of transform block Maximum, or the average value of sum wide and high maximum；

According to the size of image block, and the size of default transform block maximum, obtain the first parameter, first parameter is used In the size for representing the corresponding maximum transform block of described image block；

The minimum value of the size of dividing mode, first parameter and the default transform block according to image block, obtains the Whether two parameters, second parameter is used to represent the size of the corresponding minimum transform block of described image block more than the default change Change the minimum value of the size of block；

According to second parameter, judge whether to carry out non-square division to the transform block.

6. transform block division methods according to claim 5, it is characterised in that the size according to image block, and The maximum of the size of default transform block, obtains the first parameter, and first parameter is used to represent that described image block is corresponding most The size of big transform block includes：

When the maximum of the size that the size of described image block is more than the default transform block, first parameter is equal to described The maximum of the size of default transform block；

When the maximum of the size that the size of described image block is less than the default transform block, first parameter is equal to described The size of image block；

When the maximum of the size that the size of described image block is equal to the default transform block, first parameter is equal to described The size of image block, or first parameter is equal to the maximum of the size of the default transform block.

7. transform block division methods according to claim 5 or 6, it is characterised in that the size of described image block, default become The minimum value for changing the maximum of the size of block and the size of default transform block is adopted with 2 as the logarithm of radix is represented；

The minimum value of the size of the dividing mode, first parameter and the default transform block according to image block, obtains Obtaining the second parameter includes：

When the dividing mode of described image block is to be divided using non-square, and the value of first parameter is more than default transform block When the minimum value of size adds 1, the value of second parameter is set to 1, the value of second parameter is otherwise set to 0；

It is described according to second parameter, judge whether to carry out the transform block non-square and divide to include：

When the value of second parameter is 1, judgement allows to divide the transform block using non-square, otherwise, to the change Block is changed using square division；

Wherein, it refers to that image block or transform block are divided into wide and division methods not etc. high that the non-square is divided.

8. transform block division methods according to claim 5, it is characterised in that the non-square is divided to be included：2NxN draws Divide method, or 2NxnU division methods, or 2NxnD division methods, or Nx2N division methods, or nLx2N division methods, or nRx2N Division methods.

9. transform block division methods according to claim 5, it is characterised in that also include：

Obtain the default division number of plies that transform block allows to divide；

It is described when carrying out non-square to transform block and divide, if the size in default transform block wide or high of the transform block Minimum value, then stop carrying out division to the transform block including：

Carry out non-square division to transform block, and the division number of plies in the transform block divides the number of plies, and the change less than default During the minimum value of the size in default transform block wide or high for changing block, stop the division to the transform block.

10. transform block division methods according to claim 5, it is characterised in that also include：

Obtain the size of the maximum transform block of the corresponding chrominance block of image block；

Whether the size of the corresponding transform block of chrominance block exceedes the corresponding chrominance block of described image block most in the transform block of judgement The size of big transform block, is that the size of the corresponding transform block of the chrominance block is reset into the corresponding chrominance block of described image block Maximum transform block size.

A kind of 11. transform blocks divide the coding method of parameter, it is characterised in that including：

Obtain the minimum value of the size of default transform block；

Relation between the minimum value of the size of size and the default transform block according to transform block, judges whether transcoding, coding transform The division parameter of block；

The division parameter of the transform block is used for expression and transform block is divided or is not divided；

Relation between the minimum value of the size of the size and the default transform block according to transform block, judges whether coding The division parameter of transform block includes：

According to the second parameter, judge whether the division parameter of transcoding, coding transform block；

Also include：

Obtain the maximum of the size of the size, the dividing mode of image block and default transform block of image block；

According to the size of image block, and the size of default transform block maximum, obtain the first parameter；

The minimum value of the size of dividing mode, first parameter and the default transform block according to image block, obtains the Two parameters.

12. transform blocks according to claim 11 divide the coding method of parameter, it is characterised in that described according to transform block Size and the default transform block size minimum value between relation, judge whether the division parameter bag of transcoding, coding transform block Include：

When transform block using non-square divide, and the size in the default transform block wide or high of the transform block minimum During value, judge not needing the division parameter of transcoding, coding transform block, otherwise, the division parameter of transcoding, coding transform block.

13. transform blocks according to claim 11 divide the coding method of parameter, it is characterised in that second parameter is used Whether it is more than the minimum value of the size of the default transform block in the size for representing the corresponding minimum transform block of image block；

First parameter is used to represent the size of the corresponding maximum transform block of described image block.

14. transform blocks according to claim 13 divide the coding method of parameter, it is characterised in that described according to image block Size, and the size of default transform block maximum, obtain the first parameter include：

When the maximum of the size that the size of described image block is more than the default transform block, first parameter is equal to described The maximum of the size of default transform block；

When the maximum of the size that the size of described image block is less than the default transform block, first parameter is equal to described The size of image block；

When the maximum of the size that the size of described image block is equal to the default transform block, first parameter is equal to described The size of image block, or first parameter is equal to the maximum of the size of the default transform block.

15. transform blocks according to claim 13 divide the coding method of parameter, it is characterised in that described according to the second ginseng Number, judging whether the division parameter of transcoding, coding transform block includes：

When the minimum value that the size of the transform block is more than the size of default transform block adds second parameter, transcoding, coding transform block Division parameter, otherwise, it is not necessary to the division parameter of transcoding, coding transform block.

16. transform blocks according to claim 11 divide the coding method of parameter, it is characterised in that also include：

Obtain the default division number of plies that transform block allows to divide；

The coding method that the transform block divides parameter also includes：

When the division number of plies of transform block is equal to the default division number of plies, judge not needing the division parameter of transcoding, coding transform block.

A kind of 17. transform blocks divide the coding/decoding method of parameter, it is characterised in that including：

Obtain the minimum value of the size of default transform block；

Relation between the minimum value of the size of size and the default transform block according to transform block, judges whether decoded transform The division parameter of block；

The division parameter of the transform block is used for expression and transform block is divided or is not divided；

Relation between the minimum value of the size of the size and the default transform block according to transform block, judges whether decoding The division parameter of transform block includes：

According to the second parameter, judge whether the division parameter of decoded transform block.

18. transform blocks according to claim 17 divide the coding/decoding method of parameter, it is characterised in that also include：

Obtain the maximum of the size of the size, the dividing mode of image block and default transform block of image block；

According to the size of image block, and the size of default transform block maximum, obtain the first parameter；

The minimum value of the size of dividing mode, first parameter and the default transform block according to image block, obtains the Two parameters.

19. transform blocks according to claim 18 divide the coding/decoding method of parameter, it is characterised in that second parameter is used Whether it is more than the minimum value of the size of the default transform block in the size for representing the corresponding minimum transform block of image block；

First parameter is used to represent the size of the corresponding maximum transform block of described image block.

20. transform blocks according to claim 19 divide the coding/decoding method of parameter, it is characterised in that described according to image block Size, and the size of default transform block maximum, obtain the first parameter include：

When the maximum of the size that the size of described image block is more than the default transform block, first parameter is equal to described The maximum of the size of default transform block；

When the maximum of the size that the size of described image block is less than the default transform block, first parameter is equal to described The size of image block；

When the maximum of the size that the size of described image block is equal to the default transform block, first parameter is equal to described The size of image block, or first parameter is equal to the maximum of the size of the default transform block.

21. transform blocks according to claim 19 divide the coding/decoding method of parameter, it is characterised in that described according to the second ginseng Number, judging whether the division parameter of decoded transform block includes：

When the minimum value that the size of the transform block is more than the size of default transform block adds second parameter, decoded transform block Division parameter.

22. transform blocks according to claim 17 divide the coding/decoding method of parameter, it is characterised in that also include：

Obtain the default division number of plies that transform block allows to divide；

The coding/decoding method that the transform block divides parameter also includes：

When the division number of plies of transform block is equal to the default division number of plies, judge not needing the division parameter of decoded transform block.

A kind of 23. transform blocks divide device, it is characterised in that including：

Dimension acquisition module, the minimum value of the size for obtaining default transform block；

Transform block division module, for transform block carry out non-square divide when, if the transform block is wide or high in institute The minimum value of the size of default transform block is stated, then stops dividing the transform block；

Wherein, the minimum value of the size of the default transform block is the minimum value wide or high of transform block, or sum wide and high Average value minimum value；It refers to that image block or transform block are divided into wide and division methods not etc. high that the non-square is divided

Also include：

Judge module is divided, for judging whether to carry out non-square division to the transform block；

The division judge module includes：

Dividing mode acquiring unit, the dividing mode for obtaining image block；

First judging unit, for using horizontal division when image block, the width of the transform block is equal to the height of transform block, the change Change the sum wide and high of block average value be less than or equal to default transform block size maximum, and the width of the transform block or When the minimum value that height is at least the size of the default transform block adds 2, judge to divide the transform block using non-square so that The width of the transform block after division is equal to the width of transform block before dividing, and the height of the transform block after division is less than transform block before dividing It is high；

Second judging unit, for using vertical division when image block, the width of the transform block is equal to the height of transform block, the change Change the sum wide and high of block average value be less than default transform block size maximum, and the transform block wide or height at least When adding 2 for the minimum value of the size of the default transform block, judge to divide the transform block using non-square so that after division Transform block width of the width less than transform block before dividing, the height of the high transform block before dividing of transform block after division；

3rd judging unit, for using horizontal division or vertical division, wide and high, the institute of the transform block when image block State the sum wide and high of transform block average value be more than default transform block size maximum, and the transform block wide or height When the minimum value of the size of at least described default transform block adds 2, judge to divide the transform block using non-square so that draw The width of the transform block after point is less than the width for dividing preceding transform block, the height of the height less than transform block before dividing of the transform block after division；

Wherein, the size of the size of transform block and default transform block with 2 for the logarithm of radix is represented.

24. transform blocks according to claim 23 divide device, it is characterised in that also include：

Parameter acquisition module is divided, the default division number of plies divided for obtaining transform block to allow；

The transform block division module, specifically for carrying out non-square division to transform block, and in the division layer of the transform block Number divides the number of plies less than default, and during the minimum value of the size in default transform block wide or high of the transform block, it is right to stop The division of the transform block.

25. transform blocks according to claim 23 divide device, it is characterised in that also include：

Chromaticity transformation block size acquisition module, the size of the maximum transform block for obtaining the corresponding chrominance block of image block；

Chromaticity transformation block resets module, and whether the size for judging the corresponding transform block of chrominance block in the transform block after dividing surpasses The size of the maximum transform block of the corresponding chrominance block of described image block is crossed, is then by chrominance block pair in the transform block after the division The size of the transform block answered resets to the size of the maximum transform block of the corresponding chrominance block of described image block.

A kind of 26. transform blocks divide device, it is characterised in that including：

Dimension acquisition module, the minimum value of the size for obtaining default transform block；

Transform block division module, for transform block carry out non-square divide when, if the transform block is wide or high in institute The minimum value of the size of default transform block is stated, then stops dividing the transform block；

Wherein, the minimum value of the size of the default transform block is the minimum value wide or high of transform block, or sum wide and high Average value minimum value；It refers to that image block or transform block are divided into wide and division methods not etc. high that the non-square is divided

Also include：

Judge module is divided, for judging whether to carry out non-square division to the transform block；

The division judge module includes：

First acquisition unit, the size for obtaining the size of image block, the dividing mode of image block and default transform block Maximum, the size of described image block is the average value wide and high of image block, the maximum of the size of the default transform block Be the maximum wide and high of transform block, or the average value of sum wide and high minimum value；

First parameter acquiring unit, for the size according to image block, and the size of default transform block maximum, obtain the One parameter, first parameter is used to represent the size of the corresponding maximum transform block of described image block；

Second parameter acquiring unit, for the dividing mode according to image block, first parameter and the default transform block Size minimum value, obtain the second parameter, second parameter be used for represent the corresponding minimum transform block of described image block Whether size is more than the minimum value of the size of the default transform block；

Judging unit is divided, for according to second parameter, judging whether to carry out non-square division to the transform block.

27. transform blocks according to claim 26 divide device, it is characterised in that the first parameter acquiring unit, specific to use When the maximum of the size for being more than the default transform block when the size of described image block, first parameter is equal to described pre- If the maximum of the size of transform block；When the maximum of the size that the size of described image block is less than the default transform block, First parameter is equal to the size of described image block；And when the size of described image block is equal to the chi of the default transform block During very little maximum, first parameter is equal to the size of described image block.

28. transform blocks according to claim 26 or 27 divide device, it is characterised in that the size of described image block, pre- If the minimum value of the size of the maximum of the size of transform block and default transform block is adopted with 2 as the logarithm of radix is represented；

Second parameter acquiring unit, specifically for being to be divided using non-square when the dividing mode of described image block, and institute When stating the value of the first parameter more than the minimum value of the size for presetting transform block plus 1, the value of second parameter is set to 1, otherwise The value of second parameter is set to 0；

The division judging unit, specifically for when the value of second parameter is 1, judgement allows to use the transform block Non-square is divided, and otherwise, square division is used to the transform block；

Wherein, it refers to that image block or transform block are divided into wide and division methods not etc. high that the non-square is divided.

29. transform blocks according to claim 26 divide device, it is characterised in that also include：

Parameter acquisition module is divided, the default division number of plies divided for obtaining transform block to allow；

The transform block division module, specifically for carrying out non-square division to transform block, and in the division layer of the transform block Number divides the number of plies less than default, and during the minimum value of the size in default transform block wide or high of the transform block, it is right to stop The division of the transform block.

30. transform blocks according to claim 26 divide device, it is characterised in that also include：

Chromaticity transformation block size acquisition module, the size of the maximum transform block for obtaining the corresponding chrominance block of image block；

Chromaticity transformation block resets module, and whether the size for judging the corresponding transform block of chrominance block in the transform block after dividing surpasses The size of the maximum transform block of the corresponding chrominance block of described image block is crossed, is then by chrominance block pair in the transform block after the division The size of the transform block answered resets to the size of the maximum transform block of the corresponding chrominance block of described image block.

A kind of 31. transform blocks divide the code device of parameter, it is characterised in that including：

Dimension acquisition module, the minimum value of the size for obtaining default transform block；

Parameter coding module, for the pass between the minimum value of the size according to transform block and the size of the default transform block System, judges whether the division parameter of transcoding, coding transform block；

The division parameter of the transform block is used for expression and transform block is divided or is not divided；

The parameter coding module, specifically for according to the second parameter, judging whether the division parameter of transcoding, coding transform block；

Also include：

Second acquisition unit, the size for obtaining the size of image block, the dividing mode of image block and default transform block Maximum；

First parameter acquiring unit, for the size according to image block, and the size of default transform block maximum, obtain the One parameter；

Second parameter acquiring unit, for the dividing mode according to image block, first parameter and the default transform block Size minimum value, obtain the second parameter.

32. transform blocks according to claim 31 divide the code device of parameter, it is characterised in that the parameter coding mould Block, specifically for when transform block using non-square divide, and the transform block the chi in the default transform block wide or high During very little minimum value, judge not needing the division parameter of transcoding, coding transform block, otherwise, the division parameter of transcoding, coding transform block.

33. transform blocks according to claim 31 divide the code device of parameter, it is characterised in that second parameter is used Whether it is more than the minimum value of the size of the default transform block in the size for representing the corresponding minimum transform block of image block；

First parameter is used to represent the size of the corresponding maximum transform block of described image block.

34. transform blocks according to claim 31 divide the code device of parameter, it is characterised in that the parameter coding mould Block, when adding second parameter specifically for being more than the minimum value of size of default transform block when the size of the transform block, compiles The division parameter of code conversion block, otherwise, it is not necessary to the division parameter of transcoding, coding transform block.

35. transform blocks according to claim 31 divide the code device of parameter, it is characterised in that also include：

Parameter acquisition module is divided, the default division number of plies divided for obtaining transform block to allow；

The parameter coding module, specifically for when the division number of plies of transform block is equal to the default division number of plies, judging not Need the division parameter of transcoding, coding transform block.

A kind of 36. transform blocks divide the decoding apparatus of parameter, it is characterised in that including：

Dimension acquisition module, the minimum value of the size for obtaining default transform block；

Parameter decoding module, for the pass between the minimum value of the size according to transform block and the size of the default transform block System, judges whether the division parameter of decoded transform block；

The division parameter of the transform block is used for expression and transform block is divided or is not divided；

The parameter decoding module, specifically for according to the second parameter, judging whether the division parameter of decoded transform block.

37. transform blocks according to claim 36 divide the decoding apparatus of parameter, it is characterised in that also include：

Second acquisition unit, the size for obtaining the size of image block, the dividing mode of image block and default transform block Maximum；

First parameter acquiring unit, for the size according to image block, and the size of default transform block maximum, obtain the One parameter；

Second parameter acquiring unit, for the dividing mode according to image block, first parameter and the default transform block Size minimum value, obtain the second parameter.

38. transform block according to claim 37 divides the decoding apparatus of parameter, it is characterised in that second parameter is used Whether it is more than the minimum value of the size of the default transform block in the size for representing the corresponding minimum transform block of image block；

First parameter is used to represent the size of the corresponding maximum transform block of described image block.

39. transform block according to claim 38 divides the decoding apparatus of parameter, it is characterised in that parameter decoding module, When minimum value specifically for being more than the size of default transform block when the size of the transform block adds second parameter, decoding becomes Change the division parameter of block.

40. transform blocks according to claim 36 divide the decoding apparatus of parameter, it is characterised in that also include：

Parameter acquisition module is divided, the default division number of plies divided for obtaining transform block to allow；

The parameter decoding module, specifically for when the division number of plies of transform block is equal to the default division number of plies, judging not Need the division parameter of decoded transform block.