阅读说明：本技术 图像编译系统中根据块分离结构的图像解码方法和设备 (Image decoding method and apparatus according to block separation structure in image coding system ) 是由 南廷学 金昇焕 张炯文 林宰显 于 2018-04-03 设计创作，主要内容包括：根据本发明的借助于解码设备执行的图像解码方法包括下述步骤：获取与第一目标块有关的第一分离信息,如果第一分离标志指示第一目标块要被分离,则将第一目标块分离成第一子块；获取与作为第一目标块的第一子块之一的第二目标块有关的MPT分离信息；基于MPT分离信息将第二目标块分离成第二子块；以及对第二子块进行解码,其中,第二子块是非正方形块。(The image decoding method according to the invention, performed by means of a decoding device, comprises the following steps: obtaining first separation information related to the first target block, and separating the first target block into first sub-blocks if the first separation flag indicates that the first target block is to be separated; acquiring MPT split information on a second target block that is one of first sub-blocks of the first target block; splitting the second target block into second sub-blocks based on the MPT split information; and decoding a second sub-block, wherein the second sub-block is a non-square block.)

1. A video decoding method performed by a decoding apparatus, comprising:

acquiring first separation information for a first target block through a bitstream;

splitting the first target block into first sub-blocks when the first split flag indicates that the first target block is split;

obtaining multi-partition tree (MPT)) split information for a second target block through the bitstream, wherein the second target block is one of the first sub-blocks of the first target block;

separating the second target block into second sub-blocks based on the MPT separation information; and

the second sub-block is decoded and the first sub-block is decoded,

wherein the second sub-block is a non-square block.

2. The method of claim 1, wherein the MPT separation information includes MPT separation type information and MPT separation direction information of the second target block;

wherein the MPT separation type information indicates the number of the second sub-blocks into which the second target block is separated, and

wherein the MPT separation direction information represents a separation direction of the second target block.

3. The method of claim 2, wherein when the size of the second target block is 2 nx 2N and the number of the second sub-blocks represented by the MPT split type information is equal to 2 and the split direction of the second target block represented by the MPT split direction information represents a vertical direction, the second target block is split into N x 2N-sized second sub-blocks, and

wherein when the size of the second target block is 2N × 2N and the number of the second sub-blocks represented by the MPT split type information is equal to 2 and the split direction of the second target block represented by the MPT split direction information represents a horizontal direction, the second target block is split into 2N × N-sized second sub-blocks.

4. The method of claim 2, wherein when the size of the second target block is 2 nx 2N and the number of the second sub-blocks represented by the MPT split type information is equal to 3 and the split direction of the second target block represented by the MPT split direction information represents a vertical direction, the second target block is split into an N x 2N-sized second sub-block and an N/2 x 2N-sized second sub-block, and

wherein when the size of the second target block is 2N × 2N and the number of the second sub-blocks represented by the MPT split type information is equal to 3 and the split direction of the second target block represented by the MPT split direction information represents a horizontal direction, the second target block is split into a 2N × N-sized second sub-block and a 2N × N/2-sized second sub-block.

5. The method of claim 4, wherein the MPT separation information includes MPT sub-separation type information when the size of the second target block is 2 Nx 2N and the number of the second sub-blocks represented by the MPT separation type information is equal to 3 and the separation direction of the second target block represented by the MPT separation direction information represents a vertical direction;

wherein, when the MPT sub-separation type information indicates a type 0, a left second sub-block is derived as the Nx 2N-sized second sub-block among the second sub-blocks,

wherein, when the MPT sub-separation type information indicates type 1, a center second sub-block is derived as the Nx 2N-sized second sub-block among the second sub-blocks, and

wherein, when the MPT sub-separation type information indicates type 2, a right-side second sub-block is derived as the Nx 2N-sized second sub-block among the second sub-blocks.

6. The method of claim 4, wherein the MPT separation information includes MPT sub-separation type information when the size of the second target block is 2 Nx 2N and the number of the second sub-blocks represented by the MPT separation type information is equal to 3 and the separation direction of the second target block represented by the MPT separation direction information represents a horizontal direction;

wherein, when the MPT sub-separation type information indicates a type 0, an upper side second sub-block is derived as the 2 NxN-sized second sub-block among the second sub-blocks,

wherein, when the MPT sub-separation type information indicates type 1, a center second sub-block is derived as the 2 NxN-sized second sub-block among the second sub-blocks, and

wherein, when the MPT sub-separation type information indicates type 2, a lower side second sub-block is derived as the 2 NxN-sized second sub-block among the second sub-blocks.

7. The method of claim 2, wherein when the size of the second target block is 2 nx 2N and the number of the second sub-blocks represented by the MPT split type information is equal to 4 and the split direction of the second target block represented by the MPT split direction information represents a vertical direction, the second target block is split into N/2 x 2N-sized second sub-blocks, and

wherein when the size of the second target block is 2N × 2N and the number of the second sub-blocks represented by the MPT separation type information is equal to 4 and the separation direction of the second target block represented by the MPT separation direction information represents a horizontal direction, the second target block is separated into second sub-blocks of 2N × N/2 size.

8. The method of claim 1, wherein the MPT separation information includes a Multi-partition Tree (MPT) separation flag of the second target block,

wherein the MPT separation flag indicates whether the second target block is separated into the second sub-block of the non-square block,

wherein the MPT separation information includes MPT separation direction information and MPT separation type information for the second target block when a value of the MPT separation flag is equal to 1;

wherein the MPT separation direction information represents a separation direction of the second target block,

wherein the MPT split type information indicates the number of the second sub-blocks into which the second target block is split;

wherein when the size of the second target block is 2N × 2N and the number of the second sub-blocks represented by the MPT separation type information is equal to 2 and the separation direction of the second target block represented by the MPT separation direction information represents a vertical direction, the second target block is separated into N × 2N-sized second sub-blocks, and

wherein when the size of the second target block is 2N × 2N and the number of the second sub-blocks represented by the MPT separation type information is equal to 2 and the separation direction of the second target block represented by the MPT separation direction information represents a horizontal direction, the second target block is separated into 2N × N-sized second sub-blocks.

9. The method of claim 8, wherein when the size of the second target block is 2 nx 2N and the number of the second sub-blocks represented by the MPT split type information is equal to 3 and the split direction of the second target block represented by the MPT split direction information represents a vertical direction, the second target block is split into an N x 2N-sized second sub-block and an N/2 x 2N-sized second sub-block, and

wherein when the size of the second target block is 2 NxN and the number of the second sub-blocks represented by the MPT separation type information is equal to 3 and the separation direction of the second target block represented by the MPT separation direction information represents a horizontal direction, the second target block is separated into a 2 NxN-sized second sub-block and a 2 NxN/2-sized second sub-block.

10. The method of claim 9, wherein the MPT split information includes MPT sub-split type information when the size of the second target block is 2 nx 2N and the number of the second sub-blocks represented by the MPT split type information is equal to 3 and the split direction of the second target block represented by the MPT split direction information represents a vertical direction;

wherein, when the MPT sub-separation type information indicates a type 0, a left second sub-block is derived as the Nx 2N-sized second sub-block among the second sub-blocks,

wherein, when the MPT sub-separation type information indicates type 1, a center second sub-block is derived as the Nx 2N-sized second sub-block among the second sub-blocks, and

wherein, when the MPT sub-separation type information indicates type 2, a right-side second sub-block is derived as the Nx 2N-sized second sub-block among the second sub-blocks.

11. The method of claim 9, wherein the MPT split information includes MPT sub-split type information when the size of the second target block is 2 nx 2N and the number of the second sub-blocks represented by the MPT split type information is equal to 3 and the split direction of the second target block represented by the MPT split direction information represents a horizontal direction;

wherein, when the MPT sub-separation type information indicates a type 0, an upper side second sub-block is derived as the 2 NxN-sized second sub-block among the second sub-blocks,

wherein, when the MPT sub-separation type information indicates type 1, a center second sub-block is derived as the 2 NxN-sized second sub-block among the second sub-blocks, and

wherein, when the MPT sub-split type information indicates type 2, a lower side second sub-block is derived as the 2 NxN-sized second sub-block among the second sub-blocks.

12. The method of claim 2, wherein second separation information for the second target block is acquired through the bitstream, and the second target block is separated into the second sub-blocks based on the MPT separation information when the second target block is not separated based on the second separation information for the second target block,

wherein a number of bits of a binarized character string representing the MPT separation information is variable based on a separation type of the second target block.

13. The method of claim 1, wherein the second target block is separated into 2 or 3 second sub-blocks in a vertical direction or a horizontal direction based on the MPT separation information,

wherein when the size of the second target block is 2N × 2N and the second target block is separated into 2 second sub-blocks in the vertical direction, the second target block is separated into N × 2N-sized second sub-blocks,

wherein when the size of the second target block is 2N × 2N and the second target block is separated into 2 second sub-blocks in the horizontal direction, the second target block is separated into 2N × N second sub-blocks,

wherein, when the second target block has a size of 2 Nx 2N and the second target block is separated into 3 second sub-blocks in the vertical direction, the second target is separated into a left second sub-block of N/2 x 2N size, a center second sub-block of N x 2N size, and a right second sub-block of N/2 x 2N size, and

wherein, when the size of the second target block is 2 nxn 2N and the second target block is separated into 3 second sub-blocks in the horizontal direction, the second target is separated into an upper second sub-block of 2 nxn/2 size, a central second sub-block of 2 nxn size, and a lower second sub-block of 2 nxn/2 size.

14. The method as claimed in claim 13, wherein, when the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, a binarization string of the MPT separation information is equal to 10, and

wherein, when the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information is equal to 11.

15. A decoding apparatus that performs image decoding, comprising:

an entropy decoder acquiring first separation information for a first target block through a bitstream, and acquiring multi-partition tree (MPT) separation information for a second target block through the bitstream, wherein the second target block is one of first sub-blocks of the first target block;

a picture divider that divides the first target block into first sub-blocks and divides the second target block into second sub-blocks based on the MPT separation information when the first separation flag indicates that the first target block is separated; and

a predictor that decodes the second sub-block,

wherein the second sub-block is a non-square block.

Technical Field

The present disclosure relates to an image coding technique, and more particularly, to an image decoding method and apparatus according to a block division structure in an image coding system.

Background

Demands for high-resolution, high-quality images such as High Definition (HD) images and Ultra High Definition (UHD) images are increasing in various fields. Since the image data has high resolution and high quality, the amount of information or bits to be transmitted increases relative to conventional image data. Therefore, when image data is transmitted using a medium such as a conventional wired/wireless broadband line or stored using an existing storage medium, transmission costs and storage costs thereof increase.

Accordingly, there is a need for an efficient image compression technique for efficiently transmitting, storing, and reproducing information of high-resolution and high-quality images.

Disclosure of Invention

Technical purpose

The technical purpose of the present disclosure is to provide a method and apparatus that can enhance image coding efficiency.

Another technical object of the present disclosure is to provide a method and apparatus that can separate (or partition) pictures according to a multi-partition tree (MPT) structure.

It is still another technical object of the present disclosure to provide a method and apparatus that can separate (or partition) a picture into non-square blocks according to a multi-partition tree (MPT) structure and can perform decoding on a per non-square block basis.

Technical scheme

According to an exemplary embodiment of the present disclosure, there is provided a video decoding method performed by a decoding apparatus. The method comprises the following steps: acquiring first separation information for the first target block, and separating the first target block into first sub-blocks when the first separation flag indicates that the first target block is separated; obtaining multi-partition tree (MPT) split information for a second target block, wherein the second target block is one of the first sub-blocks of the first target block; splitting the second target block into second sub-blocks based on the MPT split information; and decoding a second sub-block, wherein the second sub-block is a non-square block.

According to another exemplary embodiment of the present disclosure, there is provided a decoding apparatus that performs image decoding. The decoding apparatus includes: an entropy decoder acquiring first separation information for a first target block through a bitstream and acquiring multi-partition tree (MPT) separation information for a second target block through the bitstream, wherein the second target block is one of first sub-blocks of the first target block; a picture divider that divides the first target block into first sub-blocks and divides the second target block into second sub-blocks based on the MPT separation information when the first separation flag indicates that the first target block is separated; and a predictor that decodes a second sub-block, wherein the second sub-block is a non-square block.

According to yet another exemplary embodiment of the present disclosure, there is provided a video encoding method performed by an encoding apparatus. The method comprises the following steps: splitting the first target block into first sub-blocks; splitting the second target block into second sub-blocks, wherein the second target block is one of the first sub-blocks; decoding the second sub-block; and generating first separation information for the first target block and MPT separation information for the second target block and encoding and outputting the generated information, wherein the second sub-block is a non-square block.

According to yet another exemplary embodiment of the present disclosure, a video encoding apparatus is provided herein. The encoding device includes: a picture divider that divides the first target block into first sub-blocks and the second target block into second sub-blocks, wherein the second target block is one of the first sub-blocks; a predictor that decodes the second sub-block; and an entropy encoder generating first separation information for the first target block and MPT separation information for the second target block, and encoding and outputting the generated information, wherein the second sub-block is a non-square block.

Advantageous effects

According to the present disclosure, a picture may be separated (or divided) into blocks having different shapes according to a multi-partition tree (MPT) structure, and by doing so, prediction efficiency may be enhanced, and overall coding efficiency may be enhanced.

According to the present disclosure, a picture may be separated (or divided) into blocks having different shapes according to a multi-partition tree (MPT) structure, and by doing so, transformation efficiency may be enhanced, and overall coding efficiency may be enhanced.

Drawings

Fig. 1 is a schematic diagram illustrating a configuration of a video encoding apparatus to which the present invention can be applied.

Fig. 2 is a schematic diagram illustrating a configuration of a video decoding apparatus to which the present invention can be applied.

Fig. 3 shows an example of separating CUs according to the syntax of a binary quadtree tree (QTBT) structure and a QTBT structure.

Fig. 4 shows an exemplary transmission of syntax for the QTBT structure of a target CU.

Fig. 5 shows an example of separating target CUs according to the QTMPT structure.

Fig. 6 shows an exemplary transmission of syntax of the QTMPT structure for the target CU.

Fig. 7 shows an exemplary transmission of syntax of the QTMPT structure for the target CU.

Fig. 8 is a general diagram of a video encoding method performed by an encoding apparatus according to the present invention.

Fig. 9 is an overall view of a video decoding method performed by a decoding apparatus according to the present invention.

Detailed Description

The present disclosure may be modified in various forms and specific embodiments thereof will be described and illustrated in the accompanying drawings. However, the examples are not intended to limit the present disclosure. The terminology used in the following description is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. An expression in the singular includes an expression in the plural as long as it is clearly read in a different manner. Terms such as "including" and "having" are intended to indicate the presence of features, numbers, steps, operations, elements, components, or combinations thereof used in the following description, and thus it should be understood that the possibility of the presence or addition of one or more different features, numbers, steps, operations, elements, components, or combinations thereof is not excluded.

On the other hand, the elements in the drawings described in the present disclosure are separately drawn for convenience of explaining different specific functions, and it is not meant that the elements are implemented by separate hardware or separate software. For example, two or more of the elements may be combined to form a single element, or one element may be divided into a plurality of elements. Embodiments in which elements are combined and/or divided are within the present disclosure without departing from the concepts of the present disclosure.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, the same reference numerals are used to designate the same elements throughout the drawings, and the same description of the same elements will be omitted.

In this specification, in general, a picture means a unit representing an image at a specific time, and a slice is a unit constituting a part of the picture. One picture may be composed of a plurality of slices, and the terms of the picture and the slices may be mixed with each other as necessary.

A pixel or a pixel may mean the smallest unit constituting one picture (or image). Further, "sample" may be used as a term corresponding to a pixel. The samples may generally represent pixels or values of pixels, may represent only pixels of a luminance component (pixel values), and may represent only pixels of a chrominance component (pixel values).

The unit indicates a basic unit of image processing. The unit may include at least one of a specific region and information related to the region. Alternatively, the unit may be mixed with terms such as block, area, and the like. Typically, an mxn block may represent a set of samples or transform coefficients arranged in M columns and N rows.

Fig. 1 schematically illustrates the structure of a video encoding apparatus to which the present disclosure is applicable.

Referring to fig. 1, the video encoding apparatus (100) may include a picture divider (105), a predictor (110), a residual processor (120), an entropy encoder (130), an adder (140), a filter (150), and a memory (160). The residual processor (120) may include a subtractor (121), a transformer (122), a quantizer (123), a re-arranger (124), a dequantizer (125), and an inverse transformer (126).

A picture divider (105) may separate an input picture into at least one processing unit.

In an example, a processing unit may be referred to as a Coding Unit (CU). In this case, the coding units may be recursively separated from the Largest Coding Unit (LCU) according to a quadtree binary tree (QTBT) structure. For example, one coding unit may be separated into a plurality of coding units of deeper depths based on a quadtree structure and/or a binary tree structure. In this case, for example, the quad tree structure may be applied first, and the binary tree structure may be applied later. Alternatively, a binary tree structure may be applied first. The compilation process according to the present disclosure may be performed based on a final compilation unit that is no longer further segregated. In this case, depending on image characteristics, the maximum coding unit may be used as the final coding unit based on coding efficiency or the like, or the coding unit may be recursively separated into lower-depth coding units as necessary and a coding unit having an optimal size may be used as the final coding unit. Here, the coding process may include processes such as prediction, transformation, and reconstruction, which will be described later.

In another example, a processing unit may include a Coding Unit (CU), a Prediction Unit (PU), or a Transform Unit (TU). The coding units may be split from a Largest Coding Unit (LCU) into deeper depth coding units according to a quadtree structure. In this case, depending on image characteristics, the maximum coding unit may be directly used as the final coding unit based on coding efficiency or the like, or the coding unit may be recursively separated into coding units of deeper depths as necessary and a coding unit having an optimal size may be used as the final coding unit. When a minimal coding unit (SCU) is set, a coding unit may not be separated into coding units smaller than the minimal coding unit. Here, the final coding unit refers to a coding unit that is divided or separated into a prediction unit or a transform unit. The prediction unit is a unit divided from the coding unit, and may be a unit of sample prediction. Here, the prediction unit may be divided into subblocks. The transform unit may be divided from the coding unit according to a quadtree structure, and may be a unit for deriving a transform coefficient and/or a unit for deriving a residual signal from the transform coefficient. Hereinafter, the coding unit may be referred to as a Coding Block (CB), the prediction unit may be referred to as a Prediction Block (PB), and the transform unit may be referred to as a Transform Block (TB). A prediction block or prediction unit may refer to a specific region in the form of blocks in a picture and includes an array of prediction samples. Further, a transform block or transform unit may refer to a specific region in the form of a block in a picture and include an array of transform coefficients or residual samples.

The predictor (110) may perform prediction on a processing target block (hereinafter, a current block), and may generate a prediction block including prediction samples of the current block. The prediction unit performed in the predictor (110) may be a coding block, or may be a transform block, or may be a prediction block.

The predictor (110) may determine whether to apply intra prediction or inter prediction to the current block. For example, the predictor (110) may determine whether to apply intra prediction or inter prediction in units of CUs.

In the case of intra prediction, the predictor (110) may derive prediction samples of the current block based on reference samples outside the current block in a picture to which the current block belongs (hereinafter, current picture). In this case, the predictor (110) may derive the prediction sample based on an average or interpolation of neighboring reference samples of the current block (case (i)), or may derive the prediction sample based on a reference sample existing in a specific (prediction) direction with respect to the prediction sample among the neighboring reference samples of the current block (case (ii)). Case (i) may be referred to as a non-directional mode or a non-angular mode, and case (ii) may be referred to as a directional mode or an angular mode. In intra-prediction, the prediction modes may include, as examples, 33 directional modes and at least two non-directional modes. The non-directional mode may include a DC mode and a planar mode. The predictor (110) may determine a prediction mode to be applied to the current block by using prediction modes applied to neighboring blocks.

In the case of inter prediction, the predictor (110) may derive prediction samples for the current block based on samples specified by the motion vector on a reference picture. The predictor (110) may derive prediction samples of the current block by applying any one of a skip mode, a merge mode, and a Motion Vector Prediction (MVP) mode. In case of the skip mode and the merge mode, the predictor (110) may use motion information of neighboring blocks as motion information of the current block. In case of the skip mode, unlike the merge mode, a difference (residual) between the prediction sample and the original sample is not transmitted. In case of the MVP mode, the motion vectors of neighboring blocks are used as a motion vector predictor, and thus, as a motion vector predictor of the current block to derive a motion vector of the current block.

In the case of inter prediction, the neighboring blocks may include spatially neighboring blocks existing in the current picture and temporally neighboring blocks existing in the reference picture. The reference picture including the temporally adjacent block may also be referred to as a collocated picture (colPic). The motion information may include a motion vector and a reference picture index. Information such as prediction mode information and motion information may be (entropy) encoded and then output as a bitstream.

When motion information of temporally adjacent blocks is used in the skip mode and the merge mode, the highest picture in the reference picture list may be used as a reference picture. Reference pictures included in the reference picture list may be aligned based on a Picture Order Count (POC) difference between the current picture and the corresponding reference picture. POC corresponds to display order and can be distinguished from coding order.

A subtractor (121) generates a residual sample, which is a difference between the original sample and the predicted sample. If skip mode is applied, residual samples may not be generated as described above.

A transformer (122) transforms the residual samples in units of transform blocks to generate transform coefficients. The transformer (122) may perform transformation based on the size of a corresponding transform block and a prediction mode applied to a coding block or a prediction block spatially overlapping with the transform block. For example, if intra prediction is applied to a coding block or a prediction block overlapping with a transform block and the transform block is a 4 × 4 residual array, residual samples may be transformed using a Discrete Sine Transform (DST) transform kernel and otherwise transformed using a Discrete Cosine Transform (DCT) transform kernel.

A quantizer (123) may quantize the transform coefficients to generate quantized transform coefficients.

A rearranger (124) rearranges the quantized transform coefficients. The rearranger (124) may rearrange the quantized transform coefficients in the form of blocks into one-dimensional vectors by a coefficient scanning method. Although the rearranger (124) is described as a separate component, the rearranger (124) may be part of the quantizer (123).

An entropy encoder (130) may perform entropy encoding on the quantized transform coefficients. Entropy encoding may include encoding methods such as exponential golomb, Context Adaptive Variable Length Coding (CAVLC), Context Adaptive Binary Arithmetic Coding (CABAC), and the like. In addition to the quantized transform coefficients, the entropy encoder (130) may perform encoding on information (e.g., syntax element values, etc.) required for video reconstruction, together or separately. Entropy coding information may be transmitted or stored in units of a Network Abstraction Layer (NAL) in the form of a bitstream.

The dequantizer (125) dequantizes the values (transform coefficients) quantized by the quantizer (123), and the inverse transformer (126) inverse transforms the values dequantized by the dequantizer (125) to generate residual samples.

An adder (140) adds the residual samples to the prediction samples to reconstruct the picture. Residual samples may be added to prediction samples in block units to generate reconstructed blocks. Although the adder (140) is described as a separate component, the adder (140) may be part of the predictor (110). Meanwhile, the adder (140) may be referred to as a reconstructor or a reconstruction block generator.

The filter (150) may apply deblocking filtering and/or sample adaptive offset to the reconstructed picture. Artifacts at block boundaries or distortion in quantization in reconstructed pictures can be corrected by deblocking filtering and/or sample adaptive shifting. After deblocking filtering is completed, sample adaptive offset may be applied in units of samples. The filter (150) may apply an Adaptive Loop Filter (ALF) to the reconstructed picture. ALF may be applied to reconstructed pictures to which deblocking filtering and/or sample adaptive offset has been applied.

The memory (160) may store information required for reconstructing a picture (decoded picture) or encoding/decoding. Here, the reconstructed picture may be a reconstructed picture filtered by the filter (150). The stored reconstructed pictures may be used as reference pictures for (inter) prediction of other pictures. For example, the memory (160) may store (reference) pictures for inter prediction. Here, the picture for inter prediction may be specified according to a reference picture set or a reference picture list.

Fig. 2 schematically illustrates the structure of a video decoding apparatus to which the present disclosure is applicable.

Referring to fig. 2, the video decoding apparatus (200) may include an entropy decoder (210), a residual processor (220), a predictor (230), an adder (240), a filter (250), and a memory (260). The residual processor (220) may include a re-arranger (221), a dequantizer (222), and an inverse transformer (223).

When a bitstream including video information is input, the video decoding apparatus (200) may reconstruct video in association with a process of processing the video information in the video encoding apparatus.

For example, the video decoding apparatus (200) may perform video decoding using a processing unit applied in the video encoding apparatus. Thus, the processing unit block of video decoding may be, for example, a coding unit, and in another example, may be a coding unit, a prediction unit, or a transform unit. The coding unit may be separated from the maximum coding unit according to a quadtree structure and/or a binary tree structure.

A prediction unit and a transform unit may be further used in some cases, and in this case, the prediction block is a block derived or divided from a coding unit, and may be a unit of sample prediction. Here, the prediction unit may be divided into subblocks. The transform unit may be separated from the coding unit according to a quadtree structure, and may be a unit that derives a transform coefficient or a unit that derives a residual signal from the transform coefficient.

The entropy decoder (210) may parse the bitstream to output information required for video reconstruction or picture reconstruction. For example, the entropy decoder (210) may decode information in a bitstream based on a coding method such as exponential golomb coding, CAVLC, CABAC, or the like, and may output a value of a syntax element required for video reconstruction and a quantized value of a transform coefficient with respect to a residual.

More specifically, the CABAC entropy decoding method may receive a bin corresponding to each syntax element in a bitstream, determine a context model using decoding target syntax element information and decoding information adjacent to and decoding a target block or information of a symbol/bin decoded in a previous step, predict bin generation probabilities according to the determined context model, and perform arithmetic decoding of the bins to generate symbols corresponding to each syntax element value. Here, the CABAC entropy decoding method may update the context model using information of the symbol/bin decoded for the context model of the next symbol/bin after determining the context model.

Information on prediction among information decoded in the entropy decoder (210) may be provided to the predictor (250), and residual values, i.e., quantized transform coefficients, on which entropy decoding has been performed by the entropy decoder (210) may be input to the rearranger (221).

The rearranger (221) may rearrange the quantized transform coefficients into a two-dimensional block form. The rearranger (221) may perform rearrangement corresponding to coefficient scanning performed by the encoding apparatus. Although the re-arranger (221) is described as a separate component, the re-arranger (221) may be part of the dequantizer (222).

A dequantizer (222) may dequantize the quantized transform coefficients based on a (de) quantization parameter to output transform coefficients. In this case, information for deriving the quantization parameter may be signaled from the encoding device.

An inverse transformer (223) may inverse transform the transform coefficients to derive residual samples.

A predictor (230) may perform prediction on the current block and may generate a prediction block including prediction samples of the current block. The unit of prediction performed in the predictor (230) may be a coding block, or may be a transform block or may be a prediction block.

The predictor (230) may determine whether to apply intra-prediction or inter-prediction based on information about the prediction. In this case, the unit for determining which one to use among intra prediction and inter prediction may be different from the unit for generating the prediction samples. In addition, the unit for generating the prediction samples may also be different in inter prediction and intra prediction. For example, it may be determined in units of CUs which one is to be applied among inter prediction and intra prediction. Also, for example, in inter prediction, prediction samples may be generated by determining a prediction mode in units of PUs, and in intra prediction, prediction samples may be generated in units of TUs by determining a prediction mode in units of PUs.

In the case of intra prediction, the predictor (230) may derive prediction samples for the current block based on neighboring reference samples in the current picture. The predictor (230) may derive prediction samples for the current block by applying a directional mode or a non-directional mode based on neighboring reference samples for the current block. In this case, the prediction mode to be applied to the current block may be determined by using the intra prediction modes of the neighboring blocks.

In the case of inter prediction, the predictor (230) may derive prediction samples for the current block based on samples specified in a reference picture according to a motion vector. The predictor (230) may derive prediction samples for the current block using one of a skip mode, a merge mode, and an MVP mode. Here, motion information required for inter prediction of a current block provided by the video encoding apparatus, for example, a motion vector and information on a reference picture index, may be acquired or derived based on the information on prediction.

In the skip mode and the merge mode, motion information of neighboring blocks may be used as motion information of the current block. Here, the neighboring blocks may include spatially neighboring blocks and temporally neighboring blocks.

The predictor (230) may construct a merge candidate list using motion information of available neighboring blocks, and use information indicated by a merge index on the merge candidate list as a motion vector of the current block. The merge index may be signaled by the encoding device. The motion information may include a motion vector and a reference picture. When motion information of temporally adjacent blocks is used in the skip mode and the merge mode, the highest picture in the reference picture list may be used as a reference picture.

In case of the skip mode, a difference (residual) between the prediction sample and the original sample is not transmitted, unlike the merge mode.

In case of the MVP mode, the motion vector of the current block may be derived using the motion vectors of neighboring blocks as a motion vector predictor. Here, the neighboring blocks may include spatially neighboring blocks and temporally neighboring blocks.

When the merge mode is applied, for example, the merge candidate list may be generated using motion vectors of reconstructed spatially neighboring blocks and/or motion vectors corresponding to Col blocks, which are temporally neighboring blocks. The motion vector of the candidate block selected from the merge candidate list is used as the motion vector of the current block in the merge mode. The above information on prediction may include a merge index indicating a candidate block having a best motion vector selected from candidate blocks included in the merge candidate list. Here, the predictor (230) may derive a motion vector of the current block using the merge index.

When a Motion Vector Prediction (MVP) mode is applied as another example, a motion vector predictor candidate list may be generated using motion vectors of reconstructed spatially neighboring blocks and/or motion vectors corresponding to Col blocks, which are temporally neighboring blocks. That is, motion vectors of reconstructed spatial neighboring blocks and/or motion vectors corresponding to Col blocks, which are temporal neighboring blocks, may be used as motion vector candidates. The above-mentioned information on prediction may include a prediction motion vector index indicating a best motion vector selected from motion vector candidates included in the list. Here, the predictor (230) may select a prediction motion vector of the current block from among motion vector candidates included in the motion vector candidate list using the motion vector index. A predictor of the encoding apparatus may obtain a Motion Vector Difference (MVD) between a motion vector of a current block and the motion vector predictor, encode the MVD, and output the encoded MVD in the form of a bitstream. That is, the MVD may be obtained by subtracting the motion vector predictor from the motion vector of the current block. Here, the predictor (230) may acquire a motion vector included in the information on prediction, and derive the motion vector of the current block by adding the motion vector difference to the motion vector predictor. In addition, the predictor may obtain or derive a reference picture index indicating a reference picture from the above-described information on prediction.

An adder (240) may add the residual samples to the prediction samples to reconstruct the current block or the current picture. The adder (240) may reconstruct the current picture by adding residual samples to the prediction samples in units of blocks. When the skip mode is applied, no residual is sent, and thus the prediction samples may become reconstructed samples. Although the adder (240) is described as a separate component, the adder (240) may be part of the predictor (230). Meanwhile, the adder (240) may be referred to as a reconstructor or a reconstruction block generator.

The filter (250) may apply deblock filtering, sample adaptive offset, and/or ALF to the reconstructed picture. Here, the sample adaptive offset may be applied in units of samples after the deblocking filtering. The ALF may be applied after deblock filtering and/or applying a sample adaptive offset.

The memory (260) may store information required for reconstructing a picture (decoded picture) or decoding. Here, the reconstructed picture may be a reconstructed picture filtered by the filter (250). For example, the memory (260) may store pictures for inter prediction. Here, the picture for inter prediction may be specified according to a reference picture set or a reference picture list. The reconstructed picture may be used as a reference picture for other pictures. The memory (260) may output the reconstructed pictures in output order.

In the case where encoding is performed on an input picture as described above, encoding may be performed on a one-processing-unit basis. The processing unit may be indicated as a Coding Unit (CU). Meanwhile, since the coding is performed in units of areas including similar information within the picture, the conversion efficiency can be improved. Also, by doing so, the overall compilation efficiency can be improved. In addition, since coding is performed in units of areas including similar information in a picture, prediction efficiency can be improved. Also, by doing so, the overall compilation efficiency can be improved. However, in the case of separating (or dividing) a picture into only square CUs only by applying a Quadtree (QT) structure, there may be a limitation in performing the separation (or division) so that CUs may accurately include similar information. For example, information indicating a specific entity within a picture may be widely located in a diagonal direction. Also, in this case, if information indicating a specific entity is included only by using one CU, a wider range of other information may be included in addition to the information indicating the specific entity. And, if information indicating a specific entity is included by using the plurality of square CUs, compiling will be performed on each of the plurality of CUs. Therefore, the compiling efficiency may be lowered. In this case, by separating the picture into non-square CUs including information indicating a specific entity, coding efficiency can be further improved. Accordingly, the present disclosure proposes a method of separating (or dividing) an input picture into a square CU and a non-square CU by using another separation structure as well as a Quadtree (QT) structure. By doing so, it is possible to separate a picture into CUs having different shapes according to information included within the picture, and it is possible to more efficiently perform compilation.

Fig. 3 shows an example of separating CUs according to the syntax of a binary quadtree tree (QTBT) structure and a QTBT structure.

The QTBT structure may indicate a structure in which CUs (or CTUs) are separated (or partitioned) according to the QT structure and then separated according to a Binary Tree (BT) structure. More specifically, a QTBT structure may indicate an isolated structure configured by a combination of QT structure and BT structure. Here, in the case of compiling pictures in units of CTUs, the CTUs may be separated (or divided) according to the QT structure, and leaf nodes of the QT structure may be additionally separated according to the BT structure. Here, a leaf node may indicate a CU that is no longer separated in the QT structure, and the leaf node may also be referred to as a terminal node. In addition, the QT structure may indicate that a 2N × 2N-sized CU (or CTU) is split into 4N × N-sized sub-CUs, and the BT structure may indicate that a 2N × 2N-sized CU is split into 2N × 2N-sized sub-CUs, or 2N × N sub-CUs. Referring to (a) of fig. 3, a CU may be separated into square CUs of lower depths according to a QT structure, and furthermore, among the square CUs, a specific CU may be separated into non-square CUs of lower depths according to a BT structure.

Fig. 3 (b) may illustrate an exemplary transmission of syntax of the QTBT structure. As shown in (b) of fig. 3, the solid line may indicate a QT structure, and the dotted line may indicate a BT structure. In addition, starting from the top and extending downward (i.e., from the top-down direction), syntax for CUs starting from a higher depth to a lower depth may be indicated. In addition, syntax for the upper-left CU, the upper-right CU, the lower-left CU, and the lower-right CU may be indicated separately from the left end toward the right end (i.e., the left-right direction). More specifically, the index shown at the highest (or uppermost) position may indicate syntax for an n-depth CU, and the index shown at the second highest position may indicate syntax for an (n +1) -depth CU, and the index shown at the third position from the top may indicate syntax for an (n +2) -depth CU, and the index shown at the fourth position from the top may indicate syntax for an (n +3) -depth CU. Furthermore, an index marked with bold words may indicate a value of a syntax corresponding to the QT structure, while an index not marked with bold words may indicate a value of a syntax corresponding to the BT structure.

Referring to fig. 3 (b), a QT split flag indicating whether or not a CU is to be split (or split) according to the QT structure may be transmitted. More specifically, a flag indicating whether to split a CU of 2N × 2N size into 4 sub-CUs of N × N size may be transmitted. QT _ split _ flag may indicate a syntax element for the QT split flag. For example, in the case where the value of the QT split flag is equal to 1, CI may be split into 4 sub-CUs. Also, in the case where the value of the QT split flag is equal to 0, the CU may not be split. In addition, in order to adjust the QT structure corresponding to the input image, information about the maximum CU size, the minimum CU size, the maximum depth, and the like within the QT structure may be transmitted. The above information on the QT structure can be transmitted separately for each slice type or for each image component (luminance component, chrominance component, etc.).

Referring to (b) of fig. 3, information on the BT structure may be transmitted for terminal nodes that are no longer separated in the QT structure. More specifically, information on the BT structure may be transmitted for CUs corresponding to the terminal nodes in the QT structure. Here, information including information on the BT structure may be referred to as MPT information. For example, a BT separation flag indicating whether separation (or division) of a CU is performed according to the BT structure, i.e., whether to apply the BT structure for the CU, may be transmitted. The BT _ split _ flag may indicate a syntax element for the BT split flag. More specifically, in the case where the value of the BT separation flag is equal to 1, the CU may be separated into 2 sub-CUs, and in the case where the value of the BT separation flag is equal to 0, the CU may not be separated. In addition, in order to adjust the BT structure corresponding to the input image, information about the maximum CU size, the minimum CU size, the maximum depth, and the like within the BT structure may be transmitted. The above information about the QT structure may be sent separately for each slice type or for each image component. In the case of separating CUs according to the BT structure, CUs may be separated in the horizontal or vertical direction. In other words, a CU of 2N × 2N size may be separated into sub-CUs of 2N × N size, or a CU of 2N × 2N size may be separated into sub-CUs of N × 2N size. A BT split mode index indicating a direction along which the CU is to be split, i.e., the split type of the CU, may be sent. BT _ split _ mode may indicate a syntax element for the BT split mode index. For example, in the case where the value of the BT split mode index is equal to 1, the CU may be split in the vertical direction, i.e., into sub-CUs of N × 2N size, and in the case where the value of the BT split mode index is equal to 0, the CU may be split in the horizontal direction, i.e., into sub-CUs of 2N × N size.

Fig. 4 shows an exemplary transmission of syntax for the QTBT structure of a target CU.

Referring to fig. 4, a QT _ split _ flag for the target CU may be transmitted. As described above, the QT _ split _ flag may indicate whether the target CU is split according to the QT structure. More specifically, the QT _ split _ flag may indicate whether the target CU is split into sub-CUs having sizes corresponding to half height and half width of the target CU.

More specifically, for example, in a case where the value of the QT _ split _ flag of the target CU is equal to 1, that is, in a case where the QT _ split _ flag indicates that the target CU is split into sub-CUs each having a size corresponding to half the height and half the width of the target CU, the target CU may be split into the corresponding sub-CUs. In this case, a QT _ split _ flag corresponding to the sub-CU may be transmitted. More specifically, the target CU may be recursively separated into lower depth CUs, thereby deriving CUs of the terminal node that can no longer be separated.

Meanwhile, in a case where a value of QT _ split _ flag of the target CU of the terminal node is equal to 0, that is, in a case where the QT _ split _ flag indicates that the target CU is not separated into sub-CUs each having a size corresponding to half height and half width of the target CU, the BT _ split _ flag corresponding to the target CU may be transmitted. As described above, the BT _ split _ flag may indicate whether the target CU is split according to the BT structure. More specifically, for example, the BT _ split _ flag indicates whether to separate a target CU of 2N × 2N size into sub-CUs of N × 2N size or sub-CUs of 2N × N size. In the case of applying the BT structure to the target CU, the shape of the CU separated from the target CU may be determined according to the BT _ split _ flag and the BT _ split _ mode values.

More specifically, in the case where the value of BT _ split _ flag is equal to 1, the target CU may be separated into N × 2N-sized sub-CUs or 2N × N-sized sub-CUs, and if the value of the BT separation flag is equal to 0, the target CU may not be separated. And, in case the BT _ split _ flag indicates that the target CU is separated according to the BT structure, the BT _ split _ mode for the target CU may be transmitted. BT _ split _ mode may indicate the direction along which the CU is to be separated, i.e. the separation type of the CU. For example, in case that the value of BT _ split _ mode is equal to 1, a CU may be split in the vertical direction, i.e., into sub-CUs of N × 2N size, and in case that the value of BT _ split _ mode is equal to 0, a CU may be split in the horizontal direction, i.e., into sub-CUs of 2N × N size.

In addition, the syntax indicating the QTBT structure may be as shown in the following table.

[ Table 1]

Here, the QT _ split _ flag may indicate a syntax element of the QT split flag described above, the BT _ split _ flag may indicate a syntax element of the BT split flag described above, and the BT _ split _ mode may indicate a syntax element of the BT split mode index described above.

The CUs may be separated and the leaf nodes of the QT structure may additionally be separated according to the MPT structure.

According to the QTBT structure described above, a target CU of 2N × 2N size corresponding to a leaf node of the QT structure may be separated into sub-CUs of 2N × 2N size, or may be separated into sub-CUs of 2N × N size. However, as shown in fig. 5 (a) to (j), the target CU corresponding to the leaf node of the QT structure may be separated into 2, 3, or 4 sub-CUs each having a different shape. More specifically, the MPT structure may represent a structure in which the target CU is separated into a plurality of non-square sub-CUs that are different in shape.

More specifically, referring to (a) and (b) of fig. 5, the target CU may be separated into 2 sub-CUs along the vertical direction or the horizontal direction according to the MPT structure. More specifically, according to the MPT structure, a target CU of 2N × 2N size may be separated into sub-CUs of 2N × 2N size, or may be separated into sub-CUs of 2N × N size.

In addition, referring to (c) to (h) of fig. 5, the target CU may be separated into 3 sub-CUs along the vertical direction or the horizontal direction according to the MPT structure. If the target CU is split into 3 sub-CUs, the target CU may be split into one large-sized sub-CU and 2 small-sized sub-CUs, or the target CU may be split equally into 3 sub-CUs, i.e., the target CU may be split into 3 equal-sized sub-CUs. The scheme for separating the target CU into one large-size sub-CU and 2 small-size sub-CUs may include various separation (or division) methods depending on the location of the large-size sub-CU.

For example, as shown in fig. 5(c), according to the MPT structure, a target CU of 2N × 2N size can be separated into one sub-CU of N/2 × 2N size, one sub-CU of N × 2N, and one sub-CU of N/2 × 2N. As shown in fig. 5(c), a target CU of 2N × 2N size may be separated in the order of one sub CU of N/2 × 2N size, one sub CU of N × 2N, and one sub CU of N/2 × 2N from left to right according to the MPT structure.

Alternatively, for example, as shown in (d) of fig. 5, a target CU of 2N × 2N size may be separated into one sub-CU of N/2 × 2N size, one sub-CU of N/2 × 2N, and one sub-CU of N × 2N according to the MPT structure. More specifically, as shown in fig. 5(d), a target CU of 2N × 2N size may be separated in the order of one sub-CU of N/2 × 2N size, one sub-CU of N/2 × 2N, and one sub-CU of N × 2N from left to right according to the MPT structure.

Alternatively, for example, as shown in (e) of fig. 5, a target CU of 2N × 2N size may be separated into one sub-CU of N × 2N size, one N/2 × 2N sub-CU, and one N/2 × 2N sub-CU according to the MPT structure. More specifically, as shown in fig. 5(e), a target CU of 2N × 2N size may be separated in the order of one sub-CU of N × 2N size, one sub-CU of N/2 × 2N, and one sub-CU of N/2 × 2N from left to right according to the MPT structure.

Alternatively, for example, as shown in (f) of fig. 5, a target CU of 2N × 2N size may be separated into one sub-CU of 2N × N/2 size, and one sub-CU of 2N × N/2 according to the MPT structure. More specifically, as shown in (f) of fig. 5, a target CU of 2N × 2N size may be separated in the order of one sub-CU of 2N × N/2 size, one sub-CU of 2N × N, and one sub-CU of 2N × N/2 from top to bottom according to the MPT structure.

Alternatively, for example, as shown in (g) of fig. 5, a target CU of 2N × 2N size may be separated into one sub-CU of 2N × N/2 size, one sub-CU of 2N × N/2, and one sub-CU of 2N × N according to the MPT structure. More specifically, as shown in fig. 5(g), a target CU of 2N × 2N size may be separated in the order of one sub-CU of 2N × N/2 size, one sub-CU of 2N × N/2, and one sub-CU of 2N × N from top to bottom according to the MPT structure.

Alternatively, for example, as shown in (h) of fig. 5, according to the MPT structure, a target CU of 2N × 2N size may be separated into one sub-CU of 2N × N size, one sub-CU of 2N × N/2, and one sub-CU of 2N × N/2. More specifically, as shown in fig. 5(h), a target CU of 2N × 2N size may be separated in the order of 1 sub-CU of 2N × N size, 1 sub-CU of 2N × N/2, and 1 sub-CU of 2N × N/2 from top to bottom according to the MPT structure.

Alternatively, for example, as shown in (i) and (j) of fig. 5, a target CU of 2N × 2N size may be separated into 4 sub-CUs along the vertical direction or the horizontal direction according to the MPT structure. More specifically, a target CU of 2N × 2N size may be separated into 4 sub-CUs of N/2 × 2N size, or may be separated into 4 sub-CUs of 2N × N/2 size. Meanwhile, if the separation according to the BT structure is recursively applied to the target CU and the sub-CUs of the target CU, the separation may be performed as shown in (i) or (j) of fig. 5. However, in the MPT structure, the target CU can be separated into 4 sub-CUs by a single separation process without repeating the separation process.

Meanwhile, in order to adjust the MPT structure corresponding to the input image, information about a maximum CU size, a minimum CU size, a maximum depth, and the like within the MPT structure may be transmitted. The above information on the MPT structure can be sent separately for each slice type or for each image component (luminance component, chrominance component, etc.). Alternatively, the above information on the MPT structure may be transmitted through a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), or a slice header, respectively.

Fig. 6 shows an exemplary transmission of syntax of the QTMPT structure for the target CU.

Referring to fig. 6, a QT _ split _ flag for the target CU may be transmitted. As described above, the QT _ split _ flag may indicate whether the target CU is split according to the QT structure. More specifically, the QT _ split _ flag may indicate whether the target CU is split into sub-CUs having sizes corresponding to half height and half width of the target CU.

More specifically, for example, in a case where the value of the QT _ split _ flag of the target CU is equal to 1, that is, in a case where the QT _ split _ flag indicates that the target CU is separated into sub-CUs each having a size corresponding to half the height and half the width of the target CU, the target CU may be separated into the corresponding sub-CUs. In this case, a QT _ split _ flag corresponding to the sub-CU may be transmitted. More specifically, the target CU may be recursively separated into lower depth CUs, thereby deriving CUs of the terminal node that can no longer be separated.

Meanwhile, in a case where a value of QT _ split _ flag for the target CU of the terminal node is equal to 0, that is, in a case where the QT _ split _ flag indicates that the target CU is not separated into sub-CUs each having a size corresponding to half height and half width of the target CU, information on the MPT structure corresponding to the target CU of the terminal node may be transmitted. Here, information including information on the MPT structure may be referred to as MPT separation information. For example, the MPT separation information may include MPT separation type information corresponding to the target CU. More specifically, in the case where the value of QT _ split _ flag corresponding to the target CU of the terminal node is equal to 0, MPT _ split _ type for the target CU may be transmitted. The MPT _ split _ type may indicate syntax for MPT split type information. The MPT _ split _ type may, for example, indicate whether to split a target CU of 2N × 2N size into a plurality of non-square sub-CUs of varying shapes. The non-square sub-CUs may include N/2 × 2N sized sub-CUs, N × 2N sized sub-CUs, 2N × N/2 sized sub-CUs, and/or 2N × N sized sub-CUs.

More specifically, for example, in the case where the value of MPT _ split _ type of the target CU is equal to 0, the target CU may not be separated. In addition, in a case where a value of MPT _ split _ type of the target CU is not equal to 0, a shape of the sub-CU separated from the target CU may be determined according to the MPT _ split _ type and the MPT _ split _ mode. More specifically, the MPT separation information may include MPT separation type information and MPT separation direction information corresponding to the target CU. Here, the MPT _ split _ type may indicate a syntax corresponding to MPT split type information, and the MPT _ split _ mode may indicate a syntax corresponding to MPT split direction information.

For example, if the value of MPT _ split _ type is equal to 1, the target CU may be split into 2 sub-CUs. More specifically, in the case where the value of MPT _ split _ type is equal to 1 and the value of MPT _ split _ mode is equal to 1, the target CU may be separated into 2N × 2N-sized sub-CUs as shown in (a) of fig. 5 described above. In addition, in the case where the value of MPT _ split _ type is equal to 1 and the value of MPT _ split _ mode is equal to 0, the target CU may be separated into 2 sub-CUs of 2N × N size, as shown in (b) of fig. 5 described above.

In addition, for example, in the case where the value of MPT _ split _ type is equal to 2, the target CU may be separated into 3 sub-CUs. In addition, in the case where the value of MPT _ split _ type is equal to 2 and the value of MPT _ split _ mode is equal to 1, the target CU may be separated into 3 sub-CUs along the vertical direction. In addition, in the case where the value of MPT _ split _ type is equal to 2 and the value of MPT _ split _ mode is equal to 0, the target CU may be split into 3 sub-CUs in the horizontal direction. In case that the separation direction of the target CU is derived based on the MPT _ split _ type, the MPT _ sub _ split _ type corresponding to the target CU may be transmitted, and the MPT _ sub _ split _ type may indicate sub-separation information of the target CU. The MPT separation information may include MPT sub-separation type information corresponding to the target CU. Also, herein, the MPT _ sub _ split _ type may indicate syntax for MPT sub-split type information.

More specifically, in the case of separating the target CU into 3 sub-CUs, the sub-separation information of the target CU may be derived based on the MPT _ sub _ split _ type.

More specifically, in the case where the value of MPT _ split _ type is equal to 2 and the value of MPT _ split _ mode is equal to 1 and the value of MPT _ sub _ split _ type is equal to 0, the target CU may be separated into one N/2 × 2N-sized left-side sub-CU, one N × 2N-sized center sub-CU, and one N/2 × 2N-sized right-side sub-CU, as shown in (c) of fig. 5 described above. In addition, in the case where the value of MPT _ split _ type is equal to 2 and the value of MPT _ split _ mode is equal to 1 and the MPT _ sub _ split _ type is equal to 1, the target CU may be separated into one N/2 × 2N-sized left sub-CU, one N/2 × 2N-sized center sub-CU, and one N × 2N-sized right sub-CU, as shown in (d) of fig. 5 described above. In addition, in the case where the value of MPT _ split _ type is equal to 2 and the value of MPT _ split _ mode is equal to 1 and the value of MPT _ sub _ split _ type is equal to 2, the target CU may be separated into one N × 2N-sized left sub-CU, one N/2 × 2N-sized center sub-CU, and one N/2 × 2N-sized right sub-CU, as shown in (e) of fig. 5 described above. In addition, in case that the value of MPT _ split _ type is equal to 2 and the value of MPT _ split _ mode is equal to 0 and the value of MPT _ sub _ split _ type is equal to 0, the target CU may be separated into one 2 nxn/2-sized upper sub-CU, one 2 nxn-sized center sub-CU, and one 2 nxn/2-sized lower sub-CU, as shown in (f) of fig. 5 described above. In addition, in the case where the value of MPT _ split _ type is equal to 2 and the value of MPT _ split _ mode is equal to 0 and MPT _ sub _ split _ type is equal to 1, the target CU may be separated into one 2N × N/2-sized upper sub-CU, 1 2N × N/2-sized center sub-CU, and 1 2N × N-sized lower sub-CU, as shown in (g) of fig. 5 described above. In addition, in case that the value of MPT _ split _ type is equal to 2 and the value of MPT _ split _ mode is equal to 0 and MPT _ sub _ split _ type is equal to 2, the target CU may be separated into one 2N × N sized upper sub-CU, one 2N × N/2 sized center sub-CU and one 2N × N/2 sized lower sub-CU, as shown in (h) of fig. 5 described above.

Also, for example, in the case where the value of MPT _ split _ type is equal to 3, the target CU may be split into 4 sub-CUs. More specifically, in the case where the value of MPT _ split _ type is equal to 3 and the value of MPT _ split _ mode is equal to 1, the target CU may be separated into 4N/2 × 2N-sized sub-CUs as shown in (i) of fig. 5 described above. In addition, in the case where the value of MPT _ split _ type is equal to 3 and the value of MPT _ split _ mode is equal to 0, the target CU may be separated into 4 sub-CUs of 2N × N/2 size, as shown in (j) of fig. 5 above.

Meanwhile, although the syntax of the QTMPT structure may be transmitted as described above, an exemplary transmission of the syntax of another QTMPT structure may be proposed as described below.

Fig. 7 shows an exemplary transmission of syntax of the QTMPT structure for the target CU. As described above in fig. 6, in the case where the value of MPT _ split _ type is not equal to 0, MPT _ split _ mode may be transmitted in common. However, referring to fig. 7, the MPT _ split _ mode can be resolved earlier than the MPT _ split _ type.

Referring to fig. 7, a QT _ split _ flag for the target CU may be transmitted. As described above, the QT _ split _ flag may indicate whether the target CU is split according to the QT structure. More specifically, the QT _ split _ flag may indicate whether the target CU is split into sub-CUs having sizes corresponding to half height and half width of the target CU.

More specifically, for example, in a case where the value of the QT _ split _ flag of the target CU is equal to 1, that is, in a case where the QT _ split _ flag indicates that the target CU is split into sub-CUs each having a size corresponding to half the height and half the width of the target CU, the target CU may be split into the corresponding sub-CUs. In this case, a QT _ split _ flag corresponding to the sub-CU may be transmitted. More specifically, the target CU may be recursively separated into lower depth CUs, thereby deriving CUs of the terminal node that can no longer be separated.

Meanwhile, in a case where a value of QT _ split _ flag of the target CU of the terminal node is equal to 0, that is, in a case where the QT _ split _ flag indicates that the target CU is not split into sub-CUs having sizes corresponding to half height and half width of the target CU, the MPT split information may include an MPT split flag of the target CU. More specifically, in the case where the value of QT _ split _ flag for the target CU of the terminal node is equal to 0, the MPT _ split _ flag for the target CU may be transmitted. The MPT _ split _ flag may indicate syntax for the MPT split flag. The MPT _ split _ flag may indicate whether the target CU is separated according to the MPT structure. More specifically, for example, the MPT _ split _ flag may indicate whether to separate a target CU of 2N × 2N size into non-square sub-CUs of varying shapes. The non-square sub-CUs may include N/2 × 2N sized sub-CUs, N × 2N sized sub-CUs, 2N × N/2 sized sub-CUs, and/or 2N × N sized sub-CUs. In the case where the value of MPT _ split _ flag is equal to 0, the target CU may not be separated. In addition, in the case where the value of MPT _ split _ flag is equal to 1, the target CU may be separated according to the MPT structure, and MPT _ split _ mode and MPT _ split _ type may be transmitted. In the case where the value of the MPT _ split _ flag is equal to 1, that is, in the case where the target CU is separated according to the MPT structure, the shape of the CU separated from the target CU may be determined according to the MPT _ split _ mode and the MPT _ split _ type.

More specifically, in the case where the value of MPT _ split _ flag is equal to 1, that is, in the case where the target CU is separated according to the MPT structure, the separation direction of the target CU may be derived based on MPT _ split _ mode. For example, in the case where the value of MPT _ split _ mode is equal to 1, the target CU may be separated in the vertical direction, and in the case where the value of MPT _ split _ mode is equal to 0, the target CU may be separated in the horizontal direction.

Subsequently, the separation type of the target CU may be derived based on the MPT _ split _ type. For example, in case the value of MPT _ split _ type is equal to 0, the target CU may be split into 2 sub-CUs. More specifically, in the case where the value of MPT _ split _ mode is equal to 1 and the value of MPT _ split _ type is equal to 0, the target CU may be separated into 2N × 2N-sized sub-CUs as described in (a) of fig. 5 above. In addition, in the case where the value of MPT _ split _ mode is equal to 0 and the value of MPT _ split _ type is equal to 0, the target CU may be separated into 2 sub-CUs of 2N × N size, as described in (b) of fig. 5 above.

In addition, as another example, in the case where the value of MPT _ split _ type is equal to 1, the target CU may be split into 3 sub-CUs. In case that the value of MPT _ split _ type is equal to 1, that is, in case of splitting the target CU into 3 sub-CUs, MPT _ sub _ split _ type for the target CU may be transmitted, and the MPT _ sub _ split _ type may indicate sub-split information of the target CU. More specifically, in the case of separating the target CU into 3 sub-CUs, the sub-separation information of the target CU may be derived based on the MPT _ sub _ split _ type.

More specifically, in the case where the value of MPT _ split _ mode is equal to 1 and the value of MPT _ split _ type is equal to 1 and the value of MPT _ sub _ split _ type is equal to 0, the target CU may be separated into one N/2 × 2N-sized left sub-CU, one N × 2N-sized center sub-CU, and one N/2 × 2N-sized right sub-CU, as shown in (c) of fig. 5 described above. In addition, in case that the value of MPT _ split _ mode is equal to 1 and the value of MPT _ split _ type is equal to 1 and the value of MPT _ sub _ split _ type is equal to 1, the target CU may be separated into one N/2 × 2N-sized left-side CU, one N/2 × 2N-sized center sub-CU, and one N × 2N-sized right-side sub-CU, as shown in (d) of fig. 5 described above. In addition, in the case where the value of MPT _ split _ mode is equal to 1 and the value of MPT _ split _ type is equal to 1 and the value of MPT _ sub _ split _ type is equal to 2, the target CU may be separated into one N × 2N-sized left sub-CU, one N/2 × 2N-sized center sub-CU, and one N/2 × 2N-sized right sub-CU, as described in (e) of fig. 5 above. In addition, in case that the value of MPT _ split _ mode is equal to 0 and the value of MPT _ split _ type is equal to 1 and the value of MPT _ sub _ split _ type is equal to 0, the target CU may be separated into one 2 nxn/2-sized upper sub-CU, one 2 nxn-sized center sub-CU, and one 2 nxn/2-sized lower sub-CU, as described above in (f) of fig. 5. In addition, in case that the value of MPT _ split _ mode is equal to 0 and the value of MPT _ split _ type is equal to 1 and the value of MPT _ sub _ split _ type is equal to 1, the target CU may be separated into one 2 nxn/2-sized upper sub-CU, one 2 nxn/2-sized center sub-CU, and one 2 nxn-sized lower sub-CU, as described above in (g) of fig. 5. Further, in case that the value of MPT _ split _ mode is equal to 0 and the value of MPT _ split _ type is equal to 1 and the value of MPT _ sub _ split _ type is equal to 2, the target CU may be separated into one 2N × N sized upper sub-CU, one 2N × N/2 sized center sub-CU and one 2N × N/2 sized lower sub-CU, as described above in (h) of fig. 5.

In addition, as another example, in the case where the value of MPT _ split _ type is equal to 2, the target CU may be split into 4 sub-CUs. More specifically, in the case where the value of MPT _ split _ mode is equal to 1 and the value of MPT _ split _ type is equal to 2, the target CU may be separated into 4N/2 × 2N-sized sub-CUs, as described above in (i) of fig. 5. In addition, in the case where the value of MPT _ split _ mode is equal to 0 and the value of MPT _ split _ type is equal to 2, the target CU may be separated into 4 sub-CUs of 2N × N/2 size, as described above in (j) of fig. 5.

As described above, the number of sub-CUs derived by separating the target CU may be derived based on the MPT _ split _ type. Meanwhile, in general, depending on an input image, the number of segmentations into which a block is separated, that is, the case of the separation type of generating the block may not be the same. More specifically, the ratio (or scale) of the block separation type may vary according to the input image. For example, the proportion of block types according to which a block is split into 2 partitions may be high, or the proportion of block types according to which a block is split into 3 partitions may be high, or the proportion of block types according to which a block is split into 4 partitions may be high. Therefore, coding efficiency can be improved by using a binarization method that allocates a binarization string having a small number of bits to a syntax having a high rate of separation type.

Accordingly, binarization strings for MPT _ slice _ type and MPT _ sub _ slice _ type of the above-described separation types shown in (a) to (j) of fig. 5, which are derived based on various binarization methods, may be derived as shown in the following table.

[ Table 2]

	Binarization method 1	Binarization method 2	Binarization method 3
				MPT-2(5(a),5(b))	0	00	0
MPT-3 type 0(5(c),5(f))	100	10	10
				MPT-3 type 1(5(d),5(g))	1010	110	1110
MPT-3 type 2(5(e),5(h))	1011	111	1111
				MPT-4(5(i),5(j))	11	01	110

Here, MPT-2 indicates a separation type according to which a block is separated (or divided) into 2 sub-blocks, as shown in (a) and (b) of fig. 5. MPT-3 type 0 indicates a separation type according to which a block is separated (or divided) into 3 subblocks, as shown and described in (c) and (f) of fig. 5, and here, MPT-3 type 0 indicates that a central subblock corresponds to a subblock having a larger size. The MPT-3 type 1 indicates a separation type according to which one block is separated (or divided) into 3 sub-blocks, as shown and described in (d) and (g) of fig. 5, and here, the MPT-3 type 1 indicates that the right sub-block or the lower sub-block corresponds to a sub-block having a larger size. The MPT-3 type 2 indicates a separation type according to which a block is separated (or divided) into 3 sub-blocks, as shown and described in (e) and (h) of fig. 5, and here, the MPT-3 type 2 indicates that a left sub-block or an upper sub-block corresponds to a sub-block having a larger size. And, MPT-4 indicates a separation type according to which a block is separated into 4 sub-blocks, as shown and described in (i) and (j) of fig. 5.

Referring to table 2, the binarization method 1 may first determine whether the separation type corresponds to MPT-2. More specifically, in the case where a first value of syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2.

In the case where the separation type of the target block does not correspond to MPT-2, that is, in the case where the first value of the syntax of the information on the MPT structure of the target block is not equal to 0, MPT-4 and MPT-4 can be distinguished from each other based on the second value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-3. And, in case that a second value of syntax of the information on the MPT structure of the target block is equal to 1, the separation type of the target block may be determined as MPT-4. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 1, in the case where MPT _ split _ type is equal to 0, the split type of the target block can be derived as MPT-2. In case of MPT _ split _ type equal to 10, the split type of the target block can be derived as MPT-3. And, in case of MPT _ split _ type equal to 11, the split type of the target block can be derived as MPT-4.

In addition, the split type of the target block is determined to be MPT-3, i.e., in case that MPT _ split _ type is equal to 10, MPT _ sub _ split _ type of the target block may be additionally transmitted. Based on the MPT _ sub _ split _ type, the split type of the target block may be determined as MPT-3 type 0, MPT-3 type 1, or MPT-3 type 2. According to the binarization method 1, in case MPT _ sub _ split _ type is equal to 0, the split type of the target block can be derived as MPT-3 type 0. In case of MPT _ sub _ split _ type equal to 10, the split type of the target block can be derived as MPT-3 type 1. And, in case of MPT _ sub _ split _ type equal to 11, the split type of the target block can be derived as MPT-3 type 2. Therefore, according to the binarization method 1, in the case where the separation type of the target block corresponds to the MPT-3 type 0, a binarization string indicating the syntax of the MPT structure of the target block may be indicated as 100. In the case where the separation type of the target block corresponds to MPT-3 type 1, a binarization string indicating syntax of the MPT structure of the target block may be indicated as 1010. In the case where the separation type of the target block corresponds to MPT-3 type 2, a binarization string indicating syntax of the MPT structure of the target block may be indicated as 1011. The binarization method may be used in a case where the ratio (or ratio) of the block having the separation type MPT-2 and the ratio (or ratio) of the block having the separation type MPT-4 within the input image are high. Therefore, the compiling efficiency can be improved.

In addition, referring to Table 2, the binarization method 2 may first determine whether the separation type corresponds to MPT-2 or MPT-4. More specifically, in the case where a first value of syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2 or MPT-4. And, in case that a first value of syntax of the acquired information on the MPT structure of the target block is not equal to 0, the split type of the target block may be determined to be MPT-3. More specifically, in the case where the separation type of the target block is determined to be MPT-2 or MPT-4, that is, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, MPT-2 and MPT-4 may be distinguished from each other based on the second value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2. And, in case that a second value of syntax of the information on the MPT structure of the target block is equal to 1, the separation type of the target block may be determined as MPT-4. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 2, in the case where MPT _ split _ type is equal to 00, the split type of the target block can be derived as MPT-2. In case of MPT _ split _ type equal to 1, the split type of the target block can be derived as MPT-3. And, in case of MPT _ split _ type equal to 01, the split type of the target block can be derived as MPT-4.

In addition, in case that the split type of the target block is determined to be MPT-3, that is, in case that MPT _ split _ type is equal to 1, MPT _ sub _ split _ type of the target block may be additionally transmitted. Based on the MPT _ sub _ split _ type, the split type of the target block may be determined as MPT-3 type 0, MPT-3 type 1, or MPT-3 type 2. According to the binarization method 2, in case MPT _ sub _ split _ type is equal to 0, the split type of the target block can be derived as MPT-3 type 0. In case of MPT _ sub _ split _ type equal to 10, the split type of the target block can be derived as MPT-3 type 1. And, in case of MPT _ sub _ split _ type equal to 11, the split type of the target block can be derived as MPT-3 type 2. Therefore, according to the binarization method 2, in the case where the separation type of the target block corresponds to the MPT-3 type 0, the binarization string indicating the syntax of the MPT structure of the target block may be indicated as 10. In the case where the separation type of the target block corresponds to MPT-3 type 1, a binarization string indicating syntax of the MPT structure of the target block may be indicated as 110. In the case where the separation type of the target block corresponds to MPT-3 type 2, a binarization string indicating syntax of the MPT structure of the target block may be represented as 111. The binarization method 2 may be used in the case where the proportion (or ratio) of the blocks having the MPT-3 separation type within the input image is greater than the proportion of the blocks having the MPT-2 separation type MPT-3. Therefore, the compiling efficiency can be improved.

Further, referring to table 2, the binarization method 3 may first determine whether the separation type corresponds to MPT-2. For example, in the case where a first value of syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2.

In the case where the split type of the target block does not correspond to MPT-2, that is, in the case where the first value of the syntax of the acquisition information on the MPT structure of the target block is not equal to 0, it may be determined whether the split type of the target block corresponds to MPT-3 type 0 based on the second value of the syntax of the acquired information on the MPT structure of the target block. For example, in the case where the second value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined to be MPT-3 type 0.

In the case where the split type of the target block does not correspond to the MPT-3 type 0, that is, in the case where the second value of the syntax of the acquisition information on the MPT structure of the target block is not equal to 0, it may be determined whether the split type of the target block corresponds to the MPT-4 based on the third value of the syntax of the information on the MPT structure of the target block. For example, in the case where the third value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-4.

In the case where the split type of the target block does not correspond to MPT-4, that is, in the case where the third value of the syntax of the acquisition information on the MPT structure of the target block is not equal to 0, it may be determined whether the split type of the target block corresponds to MPT-3 type 1 or MPT-3 type 2 based on the remaining value of the syntax of the information on the MPT structure of the target block. For example, in the case where the remaining value of the syntax of the acquired information regarding the MPT structure of the target block is equal to 10, the separation type of the target block may be determined as MPT-3 type 1. Also, in the case where the remaining value of the syntax of the acquired information on the MPT structure of the target block is equal to 11, the split type of the target block may be determined to be MPT-3 type 2. The binarization method 3 may be used in a case where the proportion (or ratio) of the blocks having the separation type of the MPT-3 type 0 is higher than the proportion (or ratio) of the blocks having the separation type of the MPT-4 type within the input image. Therefore, the compiling efficiency can be improved.

Meanwhile, a binarization method of information indicating a separation type of a target block according to an MPT structure may be adaptively selected in units of a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), a slice or a block, and the like, and transmission may be performed in units of the SPS, the PPS, the slice or the block, and the like. Alternatively, a binarization method of adaptively deriving information indicating a separation type of a target block according to an MPT structure in units of slices or blocks may be used.

Alternatively, as another example, it may be first determined whether to perform the separation on the target block according to the MPT. In this case, a binarized string indicating MPT separation (or segmentation) information may be derived as shown in the following table.

[ Table 3]

	Binarization method 1	Binarization method 2	Binary valueChemical method 3
				Without separation	0	0	0
MPT-2(5(a),5(b))	1 0	1 00	1 0
				MPT-3 type 0(5(c),5(f))	1 10 0	1 10	1 10
MPT-3 type 1(5(d),5(g))	1 10 10	1 11 0	1 11 10
				MPT-3 type 2(5(e),5(h))	1 10 11	1 11 1	1 11 11
MPT-4(5(i),5(j))	1 11	1 01	1 11 0

Here, MPT-2 indicates a separation type according to which a block is separated (or divided) into 2 sub-blocks, as shown and described in (a) and (b) of fig. 5. MPT-3 type 0 indicates a separation type according to which a block is separated (or divided) into 3 subblocks, as shown and described in (c) and (f) of fig. 5, and here, MPT-3 type 0 indicates that a central subblock has a larger size. MPT-3 type 1 indicates a type of separation according to which a block is separated (or divided) into 3 sub-blocks, as shown and described in (d) and (g) of fig. 5 above, and here, MPT-3 type 1 indicates that the right sub-block or the lower sub-block has a larger size. MPT-3 type 2 indicates a type of separation according to which a block is separated (or divided) into 3 sub-blocks, as shown and described above in (e) and (h) of fig. 5, and here, MPT-3 type 2 indicates that the left or upper sub-block has a larger size. And, MPT-4 indicates a separation type according to which a block is separated into 4 sub-blocks, as shown and described in (i) and (j) of fig. 5 above.

Referring to the binarization method 1 of table 3, it may be first determined whether to perform separation (or segmentation) according to MPT. More specifically, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the target block may not be separated according to the MPT.

In case of separating the target block according to the MPT, that is, in case that a first value of a syntax of the information on the MPT structure of the target block is not equal to 0, it may be determined whether the separation type corresponds to the MPT-2 based on a second value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2.

In the case where the separation type of the target block does not correspond to MPT-2, that is, in the case where the second value of the syntax of the information on the MPT structure of the target block is not equal to 0, MPT-3 and MPT-4 can be distinguished from each other based on the third value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where a third value of syntax of information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined to be MPT-3. And, in case that a third value of syntax of information on the MPT structure of the target block is equal to 1, the separation type of the target block may be determined as MPT-4. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 1, in the case where MPT _ split _ type is equal to 10, the split type of the target block can be derived as MPT-2. In case of MPT _ split _ type equal to 110, the split type of the target block can be derived as MPT-3. And, in case of MPT _ split _ type equal to 111, the split type of the target block can be derived as MPT-4.

In addition, the split type of the target block is determined to be MPT-3, i.e., in case that the MPT _ split _ type is equal to 110, the MPT _ sub _ split _ type of the target block may be additionally transmitted. Based on the MPT _ sub _ split _ type, the split type of the target block may be determined as MPT-3 type 0, MPT-3 type 1, or MPT-3 type 2. According to the binarization method 1, in case MPT _ sub _ split _ type is equal to 0, the split type of the target block can be derived as MPT-3 type 0. In case of MPT _ sub _ split _ type equal to 10, the split type of the target block can be derived as MPT-3 type 1. And, in case of MPT _ sub _ split _ type equal to 11, the split type of the target block can be derived as MPT-3 type 2. Therefore, according to the binarization method 1, in the case where the separation type of the target block corresponds to the MPT-3 type 0, a binarization string indicating the syntax of the MPT structure of the target block may be indicated as 1100. In the case where the separation type of the target block corresponds to the MPT-3 type 1, a binarization string indicating syntax of the MPT structure of the target block may be indicated as 11010. In the case where the separation type of the target block corresponds to the MPT-3 type 2, a binarization string indicating syntax of the MPT structure of the target block may be represented as 11011. In the case where the proportion (or ratio) of the block having the MPT-2 separation type and the proportion of the block having the MPT-4 separation type within the input image are both high, the binarization method 1 may be used. Therefore, the compiling efficiency can be improved.

In addition, referring to the binarization method 2 of table 3, it may be first determined whether to perform separation (or segmentation) according to MPT. More specifically, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the target block may not be separated according to the MPT.

In the case of separating the target block according to the MPT, that is, in the case where the first value of the syntax of the information on the MPT structure of the target block is not equal to 0, it may be first determined whether the separation type corresponds to MPT-2 or MPT-4 based on the second value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2 or MPT-4. And, in case that a second value of syntax of the acquired information on the MPT structure of the target block is not equal to 0, the split type of the target block may be determined as MPT-3. More specifically, in the case where the separation type of the target block is determined to be MPT-2 or MPT-4, that is, in the case where the second value of the syntax of the information on the MPT structure of the target block is equal to 0, MPT-2 and MPT-4 can be distinguished from each other based on the third value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where a third value of syntax of information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined to be MPT-2. And, in case that a third value of syntax of information on the MPT structure of the target block is equal to 1, the separation type of the target block may be determined as MPT-4. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 2, in the case where MPT _ split _ type is equal to 100, the split type of the target block can be derived as MPT-2. In case of MPT _ split _ type equal to 11, then the split type of the target block can be derived as MPT-3. And, in case of MPT _ split _ type equal to 101, the split type of the target block can be derived as MPT-4.

In addition, in case that the split type of the target block is determined to be MPT-3, that is, in case that MPT _ split _ type is equal to 11, MPT _ sub _ split _ type for the target block may be additionally transmitted. Based on the MPT _ sub _ split _ type, the split type of the target block may be determined as MPT-3 type 0, MPT-3 type 1, or MPT-3 type 2. According to the binarization method 2, in case MPT _ sub _ split _ type is equal to 0, the split type of the target block can be derived as MPT-3 type 0. In case of MPT _ sub _ split _ type equal to 10, the split type of the target block can be derived as MPT-3 type 1. And, in case of MPT _ sub _ split _ type equal to 11, the split type of the target block can be derived as MPT-3 type 2. Therefore, according to the binarization method 2, in the case where the separation type of the target block corresponds to the MPT-3 type 0, a binarization string indicating the syntax of the MPT structure of the target block may be indicated as 110. In the case where the separation type of the target block corresponds to MPT-3 type 1, a binarization string indicating syntax of the MPT structure of the target block may be indicated as 1110. In the case where the separation type of the target block corresponds to MPT-3 type 2, a binarization string indicating syntax of the MPT structure of the target block may be indicated as 1111. In the case where the proportion (or ratio) of the blocks having the MPT-3 separation type within the input image is greater than the proportion of the blocks having the MPT-2 separation type, the binarization method 2 may be used. Therefore, the compiling efficiency can be improved.

Further, referring to the binarization method 3 of table 3, it may be first determined whether to perform separation of the target block according to MPT. More specifically, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the target block may not be separated according to the MPT.

In the case of separating the target block according to the MPT, that is, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is not equal to 0, it may be first determined whether the separation type corresponds to MPT-2 based on the second value of the syntax of the information on the MPT structure of the target block. For example, in the case where the second value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2.

In the case where the split type of the target block does not correspond to MPT-2, that is, in the case where the second value of the syntax of the acquisition information on the MPT structure of the target block is not equal to 0, based on the third value of the syntax of the acquired information on the MPT structure of the target block, it may be determined whether the split type of the target block corresponds to MPT-3 type 0. For example, in the case where the third value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined as MPT-3 type 0.

In the case where the split type of the target block does not correspond to the MPT-3 type 0, that is, in the case where the third value of the syntax of the acquisition information on the MPT structure of the target block is not equal to 0, it may be determined whether the split type of the target block corresponds to the MPT-4 based on the fourth value of the syntax of the information on the MPT structure of the target block. For example, in the case where the fourth value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-4.

In the case where the split type of the target block does not correspond to MPT-4, that is, in the case where the fourth value of the syntax of the acquisition information on the MPT structure of the target block is not equal to 0, it may be determined whether the split type of the target block corresponds to MPT-3 type 1 or MPT-3 type 2 based on the remaining value of the syntax of the information on the MPT structure of the target block. For example, in the case where the remaining value of the syntax of the acquired information regarding the MPT structure of the target block is equal to 10, the separation type of the target block may be determined as MPT-3 type 1. Also, in the case where the remaining value of the syntax of the acquired information on the MPT structure of the target block is equal to 11, the split type of the target block may be determined to be MPT-3 type 2. The binarization method 3 may be used in a case where the proportion (or ratio) of the separation type block having the MPT-3 type 0 is higher than the proportion of the separation type block having the MPT-4 within the input image. Therefore, the compiling efficiency can be improved.

Meanwhile, a binarization method of information indicating a separation type of a target block according to an MPT structure may be adaptively selected in units of a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), a slice or a block, and the like, and transmission may be performed in units of the SPS, the PPS, the slice or the block, and the like. Alternatively, a binarization method of adaptively deriving information indicating a separation type of a target block according to an MPT structure in units of slices or blocks may be used.

Alternatively, among the above separation types, an MPT structure using only MPT-2, MPT-3 type 0, and MPT-4 and excluding MPT-3 type 1 and MPT-3 type 2 may be applied. In this case, the binarized character strings of the MPT _ slice _ type and the MPT _ sub _ slice _ type of the separation type can be derived as shown in the following table.

[ Table 4]

	Binarization method 4	Binarization method 5	Binarization method 6
				MPT-2(5(a),5(b))	0	10	10
MPT-3 type 0(5(c),5(f))	10	0	11
				MPT-4(5(i),5(j))	11	11	0

Here, MPT-2 indicates a separation type according to which a block is separated (or divided) into 2 sub-blocks, as shown and described in (a) and (b) of fig. 5 above. MPT-3 type 0 indicates a split type according to which a block is split (or divided) into 3 subblocks, as shown and described in (c) and (f) of fig. 5, and here, MPT-3 type 0 indicates that a central subblock has a larger size. And, MPT-4 indicates a separation type according to which a block is separated into 4 sub-blocks, as shown and described in (i) and (j) of fig. 5 above.

Referring to the binarization method 4 of table 4, it may be first determined whether the separation type of the target block corresponds to MPT-2. More specifically, in the case where a first value of syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2.

In the case where the split type of the target block does not correspond to MPT-2, that is, in the case where the first value of the syntax of the information on the MPT structure of the target block is not equal to 0, MPT-3 type 0 and MPT-4 can be distinguished from each other based on the second value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined as MPT-3 type 0. And, in case that a second value of syntax of the information on the MPT structure of the target block is equal to 1, the separation type of the target block may be determined as MPT-4. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 4, in the case where MPT _ split _ type is equal to 0, the split type of the target block can be derived as MPT-2. In case of MPT _ split _ type equal to 10, the split type of the target block can be derived as MPT-3 type 0. And, in case of MPT _ split _ type equal to 11, the split type of the target block can be derived as MPT-4. In the case where the proportion (or ratio) of blocks having the separation type MPT-2 within the input image is high, the binarization method 4 may be used. Therefore, the compiling efficiency can be improved.

In addition, referring to the binarization method 5 of table 4, it may be first determined whether the separation type of the target block corresponds to MPT-3 type 0. More specifically, in the case where a first value of syntax of the acquired information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined to be MPT-3 type 0.

In the case where the split type of the target block does not correspond to the MPT-3 type 0, that is, in the case where the first value of the syntax of the information on the MPT structure of the target block is not equal to 0, MPT-2 and MPT-4 can be distinguished from each other based on the second value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2. And, in case that a second value of syntax of the information on the MPT structure of the target block is equal to 1, the separation type of the target block may be determined as MPT-4. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 5, in the case where MPT _ split _ type is equal to 0, the split type of the target block can be derived as MPT-3 type 0. In case of MPT _ split _ type equal to 10, the split type of the target block can be derived as MPT-2. And, in case of MPT _ split _ type equal to 11, the split type of the target block can be derived as MPT-4. In the case where the proportion (or ratio) of the separation type blocks having MPT-3 type 0 within the input image is high, the binarization method 5 may be used. Therefore, the compiling efficiency can be improved.

In addition, referring to the binarization method 6 of table 4, it may be first determined whether the separation type of the target block corresponds to MPT-4. More specifically, in the case where a first value of syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-4.

In the case where the split type of the target block does not correspond to MPT-4, that is, in the case where the first value of the syntax of the information on the MPT structure of the target block is not equal to 0, MPT-2 and MPT-3 type 0 can be distinguished from each other based on the second value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2. And, in case that a second value of syntax of information on the MPT structure of the target block is equal to 1, the split type of the target block may be determined as MPT-3 type 0. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 6, in the case where MPT _ split _ type is equal to 0, the split type of the target block can be derived as MPT-4. In case of MPT _ split _ type equal to 10, the split type of the target block can be derived as MPT-2. And, in case of MPT _ split _ type equal to 11, the split type of the target block can be derived as MPT-3 type 0. In the case where the proportion (or ratio) of blocks having the separation type MPT-4 within the input image is high, the binarization method 6 may be used. Therefore, the compiling efficiency can be improved.

Meanwhile, a binarization method of information indicating a separation type of a target block according to an MPT structure may be adaptively selected in units of a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), a slice or a block, and the like, and transmission may be performed in units of the SPS, the PPS, the slice or the block, and the like. Alternatively, a binarization method of adaptively deriving information indicating a separation type of a target block according to an MPT structure in units of slices or blocks may be used.

Alternatively, as another example, a binarization string for MPT _ slice _ type and MPT _ sub _ slice _ type of the separation type may be derived as shown in the following table.

[ Table 5]

	Binarization method 4	Binarization method 5	Binarization method 6
				Without separation	0	0	0
MPT-2(5(a),5(b))	1 0	1 10	1 10
				MPT-3 type 0(5(c),5(f))	1 10	1 0	1 11
MPT-4(5(i),5(j))	111	111	10

Here, MPT-2 indicates a separation type according to which a block is separated (or divided) into 2 sub-blocks, as shown and described in (a) and (b) of fig. 5 above. The MPT-3 type 0 indicates a split type according to which a block is split (or divided) into 3 subblocks, as shown in (c) and (f) of fig. 5 above, and here, the MPT-3 type 0 indicates that a central subblock has a larger size. And, MPT-4 indicates a separation type of separating a block into 4 sub-blocks, as shown and described in (i) and (j) of fig. 5 above.

Referring to the binarization method 4 of table 5, it may be first determined whether to perform separation (or segmentation) according to MPT. More specifically, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the target block may not be separated according to the MPT.

In the case of separating the target block according to the MPT, that is, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is not equal to 0, it may be first determined whether the separation type corresponds to MPT-2 based on the second value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2.

In the case where the split type of the target block does not correspond to MPT-2, that is, in the case where the second value of the syntax of the information on the MPT structure of the target block is not equal to 0, MPT-3 type 0 and MPT-4 can be distinguished from each other based on the third value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where a third value of syntax of information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined as MPT-3 type 0. And, in case that a third value of syntax of information on the MPT structure of the target block is equal to 1, the separation type of the target block may be determined as MPT-4. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 4, in the case where MPT _ split _ type is equal to 10, the split type of the target block can be derived as MPT-2. In case of MPT _ split _ type equal to 110, the split type of the target block can be derived as MPT-3 type 0. And, in case of MPT _ split _ type equal to 111, the split type of the target block can be derived as MPT-4. In the case where the proportion (or ratio) of blocks having the separation type MPT-2 within the input image is high, the binarization method 4 may be used. Therefore, the compiling efficiency can be improved.

Referring to the binarization method 5 of table 5, it may be first determined whether to perform separation (or segmentation) according to MPT. More specifically, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the target block may not be separated according to the MPT.

In the case of separating the target block according to the MPT, that is, in the case where the first value of the syntax of the information on the MPT structure of the target block is not equal to 0, it may be determined whether the separation type of the target block corresponds to the MPT-3 type 0 based on the second value of the syntax of the acquired information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined to be MPT-3 type 0.

In the case where the split type of the target block does not correspond to the MPT-3 type 0, that is, in the case where the second value of the syntax of the information on the MPT structure of the target block is not equal to 0, MPT-2 and MPT-4 can be distinguished from each other based on the third value of the syntax of the information on the MPT structure of the target block. More specifically, in the case where a third value of syntax of information on the MPT structure of the target block is equal to 0, the split type of the target block may be determined to be MPT-2. And, in case that a third value of syntax of information on the MPT structure of the target block is equal to 1, the separation type of the target block may be determined as MPT-4. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 5, in the case where MPT _ split _ type is equal to 10, the split type of the target block can be derived as MPT-3 type 0. In case of MPT _ split _ type equal to 110, the split type of the target block can be derived as MPT-2. And, in case of MPT _ split _ type equal to 111, the split type of the target block can be derived as MPT-4. In the case where the proportion (or ratio) of the separation type blocks having MPT-3 type 0 within the input image is high, the binarization method 5 may be used. Therefore, the compiling efficiency can be improved.

The efficiency can be enhanced.

Referring to the binarization method 6 of table 5, it may be first determined whether to perform separation (or segmentation) according to MPT. More specifically, in the case where the first value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the target block may not be separated according to the MPT.

In the case of separating the target block according to the MPT, that is, in the case where the first value of the syntax of the information on the MPT structure of the target block is not equal to 0, it may be first determined whether the separation type of the target block corresponds to the MPT-4 based on the second value of the syntax of the acquired information on the MPT structure of the target block. More specifically, in the case where the second value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-4.

In the case where the split type of the target block does not correspond to MPT-4, that is, in the case where the second value of the syntax of the acquisition information on the MPT structure of the target block is not equal to 0, MPT-2 and MPT-3 type 0 can be distinguished from each other by the third value of the syntax based on the information on the MPT structure of the target block. More specifically, in the case where the third value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2. And, in case that a third value of syntax of the acquired information on the MPT structure of the target block is equal to 1, the split type of the target block may be determined as MPT-3 type 0. Meanwhile, the syntax may indicate the above-described MPT _ split _ type. More specifically, according to the binarization method 6, in the case where MPT _ split _ type is equal to 10, the split type of the target block can be derived as MPT-4. In case of MPT _ split _ type equal to 110, the split type of the target block can be derived as MPT-2. And, in case of MPT _ split _ type equal to 111, the split type of the target block can be derived as MPT-3 type 0. In the case where the proportion (or ratio) of blocks having the separation type MPT-4 within the input image is high, the binarization method 6 may be used. Therefore, the compiling efficiency can be improved.

Meanwhile, a binarization method of information indicating a separation type of a target block according to an MPT structure may be adaptively selected in units of a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), a slice or a block, and the like, and transmission may be performed in units of the SPS, the PPS, the slice or the block, and the like. Alternatively, a binarization method of adaptively deriving information indicating a separation type of a target block according to an MPT structure in units of slices or blocks may be used.

Alternatively, among the above separation types, an MPT structure using only MPT-2 and MPT-3 type 0 may be applied. In this case, a binarized string for MPT _ slice _ type of the separation type can be derived as shown in the following table.

[ Table 6]

	Binarization method 7
		Without separation	0
MPT-2(3(a),3(b))	1 0
		MPT-3 type 0(3(c),3(f))	1 1

Here, MPT-2 indicates a separation type according to which a block is separated (or divided) into 2 sub-blocks, as shown and described in (a) and (b) of fig. 5 above. And, the MPT-3 type 0 indicates a split type according to which the block is split (or divided) into 3 subblocks, as shown and described in (c) and (f) of fig. 5 above, and here, the MPT-3 type 0 indicates a split type in which a central subblock corresponds to a subblock having a larger size.

Referring to the binarization method 7 of table 6, it may be first determined whether to perform separation (or segmentation) according to MPT. More specifically, in a case where a first value of syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block indicates that MPT separation (or segmentation) is not performed.

In the case where the split type of the target block does not correspond to MPT split, that is, in the case where the first value of the syntax of the information on the MPT structure of the target block is not equal to 0, based on the second value of the syntax of the acquired information on the MPT structure of the target block, it may be first determined whether the split type of the target block corresponds to MPT-2 or MPT-3 type 0. More specifically, in the case where the second value of the syntax of the acquired information on the MPT structure of the target block is equal to 0, the separation type of the target block may be determined to be MPT-2.

In the case where the separation type of the target block does not correspond to MPT-2, that is, in the case where the second value of the syntax of the acquisition information on the MPT structure of the target block is not equal to 0, the type of the separation target block may be determined to be MPT-3 type 0. Meanwhile, the syntax may indicate the above-described MPT _ split _ type.

More specifically, according to the binarization method 7 of table 6, in the case where MPT _ split _ type is equal to 10, the split type of the target block can be derived as MPT-2. In case of MPT _ split _ type equal to 11, then the split type of the target block can be derived as MPT-3 type 0.

Fig. 8 is a general diagram of a video encoding method performed by an encoding apparatus according to the present invention. The method shown in fig. 8 may be performed by the encoding device disclosed in fig. 1. More specifically, for example, steps S800 to S810 of fig. 8 may be performed by a picture divider of an encoding apparatus, step S820 may be performed by a predictor of the encoding apparatus, and step S830 may be performed by an entropy encoder of the encoding apparatus.

The encoding apparatus separates (or partitions) the first target block into first sub-blocks (S800). The encoding apparatus may separate the first target block into first sub-blocks according to a Quadtree (QT) structure. More specifically, for example, the encoding apparatus may separate the first target block into 4 first sub-blocks. The first sub-blocks may each have dimensions corresponding to half the height and half the width of the target block. Meanwhile, the encoding apparatus may generate a Quadtree (QT) split flag corresponding to the first target block. The QT split flag may indicate whether or not the target block is split into sub-blocks having sizes corresponding to half the height and half the width of the target block.

The encoding apparatus separates a second target block, which is one of the first sub-blocks, into second sub-blocks (S810). The second target block may not be split according to the QT structure. The encoding apparatus may separate the second target block into the second sub-blocks without separating the second target block according to the QT structure. The second sub-block may correspond to a non-square block.

The second target block may be split into second sub-blocks according to a multi-partition tree (MPT) structure. In this case, the second target block may be separated into second sub-blocks corresponding to a plurality of non-square blocks having different shapes. The second target blocks may be separated in the vertical direction or may be separated in the horizontal direction.

For example, the second target block may be separated into 2, 3, or 4 second sub-blocks in a vertical direction or a horizontal direction according to the MPT separation structure. More specifically, in the case where the size of the second target block corresponds to 2N × 2N, the second target block may be separated into 2N × 2N-sized second sub-blocks, 2N × N-sized second sub-blocks, 1N × 2N-sized second sub-block and 2N/2 × 2N-sized second sub-blocks, 1 2N × N-sized second sub-block and 2N × N/2-sized second sub-blocks, 4N/2 × 2N-sized second sub-blocks, or 4 2N × N/2-sized second sub-blocks. Here, in the case of separating the second target block into 1N × 2N-sized second sub-blocks and 2N/2 × 2N-sized second sub-blocks, the N × 2N-sized second sub-blocks may be derived as a left-side second sub-block, a center second sub-block, or a right-side second sub-block. In addition, in the case of separating the second target block into 1 second sub-block of 2N × N size and 2 second sub-blocks of 2N × N/2 size, the second sub-block of 2N × N size may be derived as an upper second sub-block, a center second sub-block, or a lower second sub-block. Meanwhile, the encoding apparatus may generate MPT separation information indicating the MPT separation type of the second target block. The number of bits in the binarized string indicating MPT separation information may vary based on the separation type of the second target block. For example, a binarized string indicating MPT separation information most frequently applied to a separation type of a block among separation types within an input image (or target picture) may be derived as a binarized string having the smallest number of bits among the number of bits in the binarized string indicating the separation type. As shown in the above table 2 or table 3, a binarized character string of MPT separation information derived based on the separation type can be derived. For example, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 0. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 100, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1010, where the second sub-block of the N × 2N size or 2N × N size corresponds to the center second sub-block. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1011, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. Alternatively, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 00. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110, where the second sub-block of the N × 2N size or 2N × N size corresponds to the center second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 01. Alternatively, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 0. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 1110, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the center second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1111, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1100, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 11010, where the second sub-block of N × 2N size or 2N × N size corresponds to the central second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 11011, where the N × 2N-sized or 2N × N-sized second sub-block corresponds to the right-side or lower-side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 100. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 1110, where the N × 2N-sized or 2N × N-sized second sub-block corresponds to the central second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1111, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 101. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11110, where the second sub-block of the N × 2N size or 2N × N size corresponds to the center second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11111, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1110.

Alternatively, as another example, the second target block may be separated into 2, 3, or 4 second sub-blocks along the vertical direction or the horizontal direction according to the MPT separation structure. More specifically, in the case where the size of the second target block corresponds to 2N × 2N, the second target block may be separated into 2N × 2N-sized second sub-blocks, 2N × N-sized second sub-blocks, 1N × 2N-sized second sub-block and 2N/2 × 2N-sized second sub-blocks, 1 2N × N-sized second sub-block and 2N × N/2-sized second sub-blocks, 4N/2 × 2N-sized second sub-blocks, or 4 2N × N/2-sized second sub-blocks. Here, in the case of separating the second target block into 1N × 2N-sized second sub-blocks and 2N/2 × 2N-sized second sub-blocks, the N × 2N-sized second sub-blocks may be derived as a center second sub-block. In addition, in the case of separating the second target block into 1 second sub-block of 2N × N size and 2 second sub-blocks of 2N × N/2 size, the second sub-block of 2N × N size may be derived as the center second sub-block. Meanwhile, the encoding apparatus may generate MPT separation information indicating the MPT separation type of the second target block. The number of bits indicating MPT separation information in the binarized string may vary based on the separation type of the second target block. In this case, for example, as shown in the above table 4 or table 5, a binarized character string of MPT separation information derived based on the separation type can be derived. For example, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 0. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. Alternatively, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 0. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. Alternatively, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 0. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10.

Alternatively, as another example, the second target block may be separated into 2 or 3 second sub-blocks in a vertical direction or a horizontal direction according to the MPT separation structure. More specifically, the second target block may be separated into 2 or 3 second sub-blocks along the vertical direction or the horizontal direction based on the MPT separation information. Here, in the case where the size of the second target block corresponds to 2N × 2N and the second target block is separated into 2 second sub-blocks in the vertical direction, the second target block may be separated into N × 2N-sized second sub-blocks. Also, in the case where the size of the second target block corresponds to 2N × 2N and the second target block is separated into 2 second sub-blocks in the horizontal direction, the second target block may be separated into 2N × N second sub-blocks in size. Also, in case that the size of the second target block corresponds to 2N × 2N and the second target block is separated into 3 second sub-blocks in the vertical direction, the second target block may be separated into one left second sub-block of N/2 × 2N size, one center second sub-block of N × 2N size, and one right second sub-block of N/2 × 2N size. Also, in case that the size of the second target block corresponds to 2N × 2N and the second target block is separated into 3 second sub-blocks in the horizontal direction, the second target block may be separated into one upper second sub-block of 2N × N/2 size, one central second sub-block of 2N × N/2 size, and one lower second sub-block of 2N × N/2 size. Meanwhile, the encoding apparatus may generate MPT separation information indicating the MPT separation type of the second target block. The number of bits indicating MPT separation information in the binarized string may vary according to the separation type of the second target block. In this case, for example, a binarized character string of MPT separation information derived based on the separation type may be derived as shown in table 6 above. For example, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. Also, in the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. In addition, the binarization character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT.

The encoding apparatus decodes the second sub-block (S820). The encoding device may perform a process such as transform, intra/inter prediction, etc., on the second sub-block and may generate reconstructed samples corresponding to the second sub-block. And, then, the encoding apparatus may generate a reconstructed picture based on the generated reconstructed sample.

The encoding apparatus generates first separation information for the first target block and MPT separation information for the second target block, and encodes and outputs the generated information (S830). The encoding apparatus may encode the first separation information and the MPT separation information corresponding to the second target block, and may output the encoded information through a bitstream, and the bitstream may be stored in a recording medium (non-transitory computer-readable medium). The encoding apparatus may generate first separation information corresponding to the first target block. The first split information may include a Quadtree (QT) split flag corresponding to the first target block. The QT split flag may indicate whether or not the target block is split into sub-blocks having sizes corresponding to half the height and half the width of the target block. In addition, the encoding apparatus may generate second split information corresponding to the second target block, and the second split information may include a QT split flag corresponding to the second target block.

Further, the encoding apparatus may generate MPT separation information corresponding to the second target block. Meanwhile, in the case of separating the second target block based on the QT separation information corresponding to the second target block, the MPT separation information may be generated. More specifically, the MPT split information can be generated without splitting the second target block according to the QT structure.

For example, the MPT split information may include multi-partition tree (MPT) split type information and MPT split direction information corresponding to the second target block. The MPT split type information may indicate the number of second sub-blocks into which the second target block is split. And, the MPT separation direction information may indicate a separation direction of the second target block. More specifically, in the case where the value of the MPT split type information is equal to 0, the MPT split type information may indicate that the second target block is not split. In case that the value of the MPT split type information is equal to 1, the MPT split type information may indicate that the number of second sub-blocks is equal to 2. In case that the value of the MPT split type information is equal to 2, the MPT split type information may indicate that the number of second sub-blocks is equal to 3. And, in case that the value of the MPT split type information is equal to 3, the MPT split type information may indicate that the number of second sub-blocks is equal to 4. In addition, in the case where the value of the MPT separation direction information is equal to 0, this may indicate that the separation direction of the second target block corresponds to the horizontal direction. Also, in the case where the value of the MPT separation direction information is equal to 1, this may indicate that the separation direction of the second target block corresponds to the vertical direction.

In addition, in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, the MPT split information may include MPT sub-split type information corresponding to the second target block. In the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, it may be indicated whether the split type of the second target block corresponds to type 0, type 1, or type 2. More specifically, in the case where the value of the MPT sub-split type information is equal to 0, the MPT sub-split type information may indicate type 0. In case that the value of the MPT sub-split type information is equal to 1, the MPT sub-split type information may indicate type 1. In case that the value of the MPT sub-split type information is equal to 2, the MPT sub-split type information may indicate type 2. In case that the MPT sub-division type information indicates type 0, a left second sub-block among the second sub-blocks may be derived as an N × 2N sized second sub-block. In case that the MPT sub-division type information indicates type 1, among the second sub-blocks, a center second sub-block may be derived as an N × 2N sized second sub-block. In the case where the MPT sub-division type information indicates type 2, among the second sub-blocks, the right second sub-block may be derived as an N × 2N sized second sub-block.

In addition, in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the MPT split information may include MPT sub-split type information corresponding to the second target block. In the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, it may be indicated whether the split type of the second target block corresponds to type 0, type 1, or type 2. More specifically, in the case where the value of the MPT sub-split type information is equal to 0, the MPT sub-split type information may indicate type 0. In case that the value of the MPT sub-split type information is equal to 1, the MPT sub-split type information may indicate type 1. In case that the value of the MPT sub-split type information is equal to 2, the MPT sub-split type information may indicate type 2. In case that the MPT sub-division type information indicates type 0, among the second sub-blocks, an upper side second sub-block may be derived as a 2N × N sized second sub-block. In case that the MPT sub-division type information indicates type 1, among the second sub-blocks, a central second sub-block may be derived as a 2N × N sized second sub-block. In case that the MPT sub-division type information indicates type 2, among the second sub-blocks, a lower side second sub-block may be derived as a 2N × N sized second sub-block.

In addition, as another example, the MPT split information may include a multi-partition tree (MPT) split flag for the second target block. The MPT split flag may indicate whether the second target block is split into second sub-blocks corresponding to non-square blocks. More specifically, in the case where the value of the MPT separate flag is equal to 0, the MPT separate flag may indicate that the second target block is not separated. And, in case that the value of the MPT split flag is equal to 1, the MPT split flag may indicate that the second target block is split into the second sub-blocks according to the MPT structure. More specifically, in the case where the value of the MPT split flag is equal to 1, the MPT split flag may indicate that the second target block is split into the second sub-blocks corresponding to the non-square blocks.

In addition, in the case where the value of the MPT separation flag is equal to 1, the MPT separation information may include MPT separation direction information and MPT separation type information of the second target block. The MPT separation direction information may indicate a separation direction of the second target block. And, the MPT split type information may indicate the number of second sub-blocks into which the second target block is split. More specifically, in the case where the value of the MPT separation direction information is equal to 0, this may indicate that the separation direction of the second target block corresponds to the horizontal direction. Also, in the case where the value of the MPT separation direction information is equal to 1, this may indicate that the separation direction of the second target block corresponds to the vertical direction. In addition, in case that the value of the MPT split type information is equal to 0, the MPT split type information may indicate that the number of second sub-blocks is equal to 2. In case that the value of the MPT split type information is equal to 1, the MPT split type information may indicate that the number of second sub-blocks is equal to 3. And, in case that the value of the MPT split type information is equal to 2, the MPT split type information may indicate that the number of second sub-blocks is equal to 4.

In addition, in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, the MPT split information may include MPT sub-split type information corresponding to the second target block. In the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, it may be indicated whether the split type of the second target block corresponds to type 0, type 1, or type 2. More specifically, in the case where the value of the MPT sub-split type information is equal to 0, the MPT sub-split type information may indicate type 0. In case that the value of the MPT sub-split type information is equal to 1, the MPT sub-split type information may indicate type 1. In case that the value of the MPT sub-split type information is equal to 2, the MPT sub-split type information may indicate type 2. In case that the MPT sub-division type information indicates type 0, among the second sub-blocks, the left second sub-block may be derived as an N × 2N sized second sub-block. In case that the MPT sub-division type information indicates type 1, among the second sub-blocks, the center second sub-block may be derived as a second sub-block of N × 2N size. In the case where the MPT sub-division type information indicates type 2, among the second sub-blocks, the right second sub-block may be derived as an N × 2N sized second sub-block.

In addition, in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the MPT split information may include MPT sub-split type information corresponding to the second target block. In the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, it may be indicated whether the split type of the second target block corresponds to type 0, type 1, or type 2. More specifically, in the case where the value of the MPT sub-split type information is equal to 0, the MPT sub-split type information may indicate type 0. In case that the value of the MPT sub-split type information is equal to 1, the MPT sub-split type information may indicate type 1. In case that the value of the MPT sub-split type information is equal to 2, the MPT sub-split type information may indicate type 2. In case that the MPT sub-division type information indicates type 0, among the second sub-blocks, an upper side second sub-block may be derived as a 2N × N sized second sub-block. In case that the MPT sub-division type information indicates type 1, among the second sub-blocks, a central second sub-block may be derived as a 2N × N sized second sub-block. In case that the MPT sub-division type information indicates type 2, among the second sub-blocks, a lower side second sub-block may be derived as a 2N × N sized second sub-block.

Meanwhile, the MPT separation information may be signaled via a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), or a slice header, etc.

In addition, the number of bits in the binarized string indicating MPT separation information may vary based on the separation type of the second target block. For example, a binarized string indicating MPT separation information most frequently applied to a separation type of a block among separation types within an input image (or target picture) may be derived as a binarized string having the smallest number of bits among the number of bits in the binarized string indicating the separation type. The binarized character string of the MPT separation information derived based on the separation type may be derived as shown in the above table 2, table 3, table 4, table 5, or table 6. Meanwhile, the bitstream including the MPT separation information may be transmitted to the decoding apparatus via a network or a (digital) storage medium. Here, the network may include a broadcasting network and/or a communication network, etc., and the digital storage medium may include various storage media such as USB, SD, CD, DVD, blu-ray, HDD, SSD, etc.

Fig. 9 is an overall view of a video decoding method performed by a decoding apparatus according to the present invention. The method shown in fig. 9 may be performed by the decoding device disclosed in fig. 2. More specifically, for example, steps S900 and S920 may be performed by an entropy decoder of the decoding apparatus, steps S910 and S930 may be performed by a picture divider of the decoding apparatus, and step S940 may be performed by a predictor of the decoding apparatus.

The decoding apparatus acquires first separation information for the first target block through the bitstream (S900). The decoding apparatus may acquire first separation information corresponding to the first target block through the bitstream. The first information may include a Quadtree (QT) split flag corresponding to the first target block. The QT split flag may indicate whether or not the target block is split into sub-blocks having sizes corresponding to half the height and half the width of the target block.

When the first separation information indicates that the first target block is separated, the decoding apparatus separates the first target block into first sub-blocks (S910). In the case where the QT split flag included in the first split information indicates that the first target block is being split, the decoding apparatus may split the first target block into first sub-blocks. For example, the first target block may be separated into 4 first sub-blocks, and the first sub-blocks may correspond to sub-blocks having a size corresponding to half the height and half the width of the target block.

The decoding apparatus acquires MPT separation information of a second target block, which is one of the first sub-blocks of the first target block (S920). The decoding apparatus may acquire MPT separation information of the second target block through the bitstream. Further, the MPT separation information may be signaled via a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), or a slice header.

The decoding apparatus separates the second target block into second sub-blocks based on the MPT separation information (S930). The decoding apparatus may split the second target block into the second sub-blocks according to a multi-partition tree (MPT) split type, which is derived based on the MPT split information. Meanwhile, second separation information corresponding to the second target block may be acquired through the bitstream, and the second target block may be separated into second sub-blocks based on the MPT separation information without separating the second target block based on the second separation information corresponding to the second target block. More specifically, the second split information may include a QT split flag for the second target block. In the case where the QT split flag corresponding to the second target block indicates that the second target block is not split into sub-blocks having sizes corresponding to half the height and half the width of the second target block, the MPT split information may be acquired. More specifically, the MPT split information can be acquired without splitting the second target block based on the QT split flag corresponding to the second target block.

For example, the second target block may be separated into 2, 3, or 4 second sub-blocks in a vertical direction or a horizontal direction based on the MPT separation information. More specifically, in the case where the size of the second target block corresponds to 2N × 2N, the second target block may be separated into 2N × 2N-sized second sub-blocks, 2N × N-sized second sub-blocks, 1N × 2N-sized second sub-block and 2N/2 × 2N-sized second sub-blocks, 1 2N × N-sized second sub-block and 2N × N/2-sized second sub-blocks, 4N/2 × 2N-sized second sub-blocks, or 4 2N × N/2-sized second sub-blocks. Here, in the case of separating the second target block into 1N × 2N-sized second sub-blocks and 2N/2 × 2N-sized second sub-blocks, the N × 2N-sized second sub-blocks may be derived as a left second sub-block, a center second sub-block, or a right second sub-block. In addition, in the case of separating the second target block into 1 second sub-block of 2N × N size and 2 second sub-blocks of 2N × N/2 size, the second sub-block of 2N × N size may be derived as the upper second sub-block, the center second sub-block, or the lower second sub-block. Meanwhile, the number of bits in the binarized string indicating MPT separation information may vary based on the separation type of the second target block. For example, a binarized character string indicating MPT separation information most frequently applied to a separation type of a block among separation types within an input image (or target picture) may be taken as a binarized character string having the smallest number of bits among the binarized character strings indicating the separation types. As shown in the above table 2 or table 3, a binarized character string of MPT separation information derived based on the separation type can be derived. For example, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 0. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 100, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1010, where the second sub-block of the N × 2N size or 2N × N size corresponds to the center second sub-block. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1011, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. Alternatively, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 00. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110, where the second sub-block of the N × 2N size or 2N × N size corresponds to the center second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 01. Alternatively, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 0. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 1110, where the N × 2N-sized or 2N × N-sized second sub-block corresponds to the central second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1111, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1100, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 11010, where the second sub-block of N × 2N size or 2N × N size corresponds to the central second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 11011, where the N × 2N-sized or 2N × N-sized second sub-block corresponds to the right-side or lower-side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 100. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 1110, where the N × 2N-sized or 2N × N-sized second sub-block corresponds to the central second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1111, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 101. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110, where the second sub-block of the N × 2N size or the 2N × N size corresponds to the left or upper side second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11110, where the second sub-block of the N × 2N size or 2N × N size corresponds to the center second sub-block. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11111, where the second sub-block of the N × 2N size or 2N × N size corresponds to the right or lower side second sub-block. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 1110.

Alternatively, as another example, the second target block may be separated into 2, 3, or 4 second sub-blocks in a vertical direction or a horizontal direction according to the MPT separation structure. More specifically, in the case where the size of the second target block corresponds to 2N × 2N, the second target block may be separated into 2N × 2N-sized second sub-blocks, 2N × N-sized second sub-blocks, 1N × 2N-sized second sub-block and 2N/2 × 2N-sized second sub-blocks, 1 2N × N-sized second sub-block and 2N × N/2-sized second sub-blocks, 4N/2 × 2N-sized second sub-blocks, or 4 2N × N/2-sized second sub-blocks. Here, in the case of separating the second target block into 1N × 2N-sized second sub-blocks and 2N/2 × 2N-sized second sub-blocks, the N × 2N-sized second sub-blocks may be derived as the center second sub-block. In addition, in the case of separating the second target block into 1 second sub-block of 2N × N size and 2 second sub-blocks of 2N × N/2 size, the second sub-block of 2N × N size may be derived as the center second sub-block. Meanwhile, the number of bits in the binarized string indicating MPT separation information may vary based on the separation type of the second target block. In this case, for example, as shown in the above table 4 or table 5, a binarized character string of MPT separation information derived based on the separation type can be derived. For example, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 0. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. Alternatively, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 0. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. Alternatively, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarization character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 0. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110. In the case where the second target block is separated into 3 second sub-blocks along the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111. Alternatively, the binarized character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT. In the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 110. In the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 111. In the case where the second target block is separated into 4 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10.

Alternatively, as another example, the second target block may be separated into 2 or 3 second sub-blocks in a vertical direction or a horizontal direction based on the MPT separation information. More specifically, the second target block may be separated into 2 or 3 second sub-blocks along the vertical direction or the horizontal direction based on the MPT separation information. Here, in the case where the size of the second target block corresponds to 2N × 2N and the second target block is separated into 2 second sub-blocks in the vertical direction, the second target block may be separated into N × 2N-sized second sub-blocks. Also, in the case where the size of the second target block corresponds to 2N × 2N and the second target block is separated into 2 second sub-blocks in the horizontal direction, the second target block may be separated into 2N × N second sub-blocks. Also, in case that the size of the second target block corresponds to 2N × 2N and the second target block is separated into 3 second sub-blocks in the vertical direction, the second target block may be separated into one left second sub-block of N/2 × 2N size, one center second sub-block of N × 2N size, and one right second sub-block of N/2 × 2N size. Also, in case that the size of the second target block corresponds to 2N × 2N and the second target block is separated into 3 second sub-blocks in the horizontal direction, the second target block may be separated into one upper second sub-block of 2N × N/2 size, one central second sub-block of 2N × N/2 size, and one lower second sub-block of 2N × N/2 size. Meanwhile, the number of bits in the binarized string indicating MPT separation information may vary based on the separation type of the second target block. In this case, for example, a binarized character string of MPT separation information derived based on the separation type may be derived as shown in table 6 above. For example, in the case where the second target block is separated into 2 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 10. Also, in the case where the second target block is separated into 3 second sub-blocks in the vertical direction or the horizontal direction, the binarized character string of the MPT separation information may be equal to 11. In addition, the binarization character string of the MPT separation information may be equal to 0 without separating the second target block according to the MPT.

Meanwhile, the MPT separation information may include the following information.

For example, the MPT split information may include multi-partition tree (MPT) split type information and MPT split direction information corresponding to the second target block. The MPT split type information may indicate the number of second sub-blocks into which the second target block is split. And, the MPT separation direction information may indicate a separation direction of the second target block. More specifically, in the case where the value of the MPT split type information is equal to 0, the MPT split type information may indicate that the second target block is not split. In case that the value of the MPT split type information is equal to 1, the MPT split type information may indicate that the number of second sub-blocks is equal to 2. In case that the value of the MPT split type information is equal to 2, the MPT split type information may indicate that the number of second sub-blocks is equal to 3. And, in case that the value of the MPT split type information is equal to 3, the MPT split type information may indicate that the number of second sub-blocks is equal to 4. In addition, in the case where the value of the MPT separation direction information is equal to 0, this may indicate that the separation direction of the second target block corresponds to the horizontal direction. Also, in the case where the value of the MPT separation direction information is equal to 1, this may indicate that the separation direction of the second target block corresponds to the vertical direction. The second target block may be split into second sub-blocks based on the MPT split information.

Here, in the case where the size of the second target block corresponds to 2N × 2N and the number of second sub-blocks indicated by the MPT split information is equal to 2, and in the case where the split direction of the second target block is indicated by the MPT split direction information to correspond to the vertical direction, the second target block may be split into N × 2N-sized second sub-blocks. Also, in a case where the size of the second target block corresponds to 2N × 2N and the number along the second sub-block indicated by the MPT split information is equal to 2, and in a case where the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the second target block may be split into second sub-blocks of 2N × N size.

In addition, as another example, in the case where the size of the second target block is equal to 2N × 2N, and in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the splitting direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, the second target block may be split into N × 2N-sized second sub-blocks and N/2 × 2N-sized second sub-blocks. And, in case that the size of the second target block is equal to 2N × 2N, and in case that the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the split direction of the second target block indicated by the second split direction information corresponds to the horizontal direction, the second target block may be split into the second sub-block of 2N × N size and the second sub-block of 2N × N/2 size. In this case, for example, in the case where the splitting direction of the second target block indicated by the MPT splitting direction information corresponds to the vertical direction, among the second sub-blocks, the center second sub-block may be derived as an N × 2N-sized second sub-block. Also, in the case where the splitting direction of the second target block indicated by the MPT splitting direction information corresponds to the horizontal direction, among the second sub-blocks, the center second sub-block may be derived as a second sub-block of 2N × N size. Meanwhile, in the case where the size of the second target block is equal to 2N × 2N, and in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3, and in the case where the block split direction of the second target indicated by the MPT split direction information corresponds to the vertical direction, the MPT split information may include MPT sub-split type information. In case that the value of the MPT sub-split type information is equal to 0, the MPT sub-split type information may indicate type 0. In case that the value of the MPT sub-split type information is equal to 1, the MPT sub-split type information may indicate type 1. And, in case that the value of the MPT sub-separation type information is equal to 2, the MPT sub-separation type information may indicate type 2. In case that the MPT sub-division type information indicates type 0, among the second sub-blocks, the left second sub-block may be derived as an N × 2N sized second sub-block. In case that the MPT sub-division type information indicates type 1, among the second sub-blocks, a central second sub-block may be derived as an N × 2N sized second sub-block. And, in case the MPT sub-split type information indicates type 2, a right second sub-block of the second sub-blocks may be derived as an N × 2N sized second sub-block. In addition, in the case where the size of the second target block is equal to 2N × 2N, and in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3, and in the case where the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the MPT split information may include the MPT sub-split type information. In case that the value of the MPT sub-split type information is equal to 0, the MPT sub-split type information may indicate type 0. In case that the value of the MPT sub-split type information is equal to 1, the MPT sub-split type information may indicate type 1. And, in case that the value of the MPT sub-separation type information is equal to 2, the MPT sub-separation type information may indicate type 2. In case that the MPT sub-division type information indicates type 0, among the second sub-blocks, an upper side second sub-block may be derived as a 2N × N sized second sub-block. In case that the MPT sub-division type information indicates type 1, among the second sub-blocks, a central second sub-block may be derived as a 2N × N sized second sub-block. And, in case the MPT sub-division type information indicates type 2, among the second sub-blocks, a lower side second sub-block may be derived as a 2N × N sized second sub-block.

Here, in the case where the size of the second target block corresponds to 2N × 2N and the number of second sub-blocks indicated by the MPT split information is equal to 4, and in the case where the split direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, the second target block may be split into N/2 × 2N-sized second sub-blocks. And, in a case where the size of the second target block corresponds to 2N × 2N and the number of second sub-blocks indicated by the MPT split information is equal to 4, and in a case where the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the second target block may be split into second sub-blocks of 2N × N/2 size.

Meanwhile, as another example, the MPT split information may include a multi-partition tree (MPT) split flag for the second target block. The MPT split flag may indicate whether the second target block is being split into a second sub-block corresponding to a non-square block. More specifically, in the case where the value of the MPT separate flag is equal to 0, the MPT separate flag may indicate that the second target block is not separated. And, in case that the value of the MPT split flag is equal to 1, the MPT split flag may indicate that the second target block is split into the second sub-blocks according to the MPT structure. More specifically, in the case where the value of the MPT split flag is equal to 1, the MPT split flag may indicate that the second target block is split into the second sub-blocks corresponding to the non-square blocks.

In addition, in the case where the value of the MPT separation flag is equal to 1, the MPT separation information may include MPT separation direction information and MPT separation type information of the second target block. The MPT separation direction information may indicate a separation direction of the second target block. And, the MPT split type information may indicate the number of second sub-blocks into which the second target block is split. More specifically, in the case where the value of the MPT separation direction information is equal to 0, this may indicate that the separation direction of the second target block corresponds to the horizontal direction. Also, in the case where the value of the MPT separation direction information is equal to 1, this may indicate that the separation direction of the second target block corresponds to the vertical direction. In addition, in case that the value of the MPT split type information is equal to 0, the MPT split type information may indicate that the number of second sub-blocks is equal to 2. In case that the value of the MPT split type information is equal to 1, the MPT split type information may indicate that the number of second sub-blocks is equal to 3. And, in case that the value of the MPT split type information is equal to 2, the MPT split type information may indicate that the number of second sub-blocks is equal to 4. The second target block may be separated into second sub-blocks based on the MPT separation information.

Here, in the case where the size of the second target block corresponds to 2N × 2N and the number along the second sub-block indicated by the MPT split information is equal to 2, and in the case where the split direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, the second target block may be split into N × 2N-sized second sub-blocks. And, in a case where the size of the second target block corresponds to 2N × 2N and the number along the second sub-block indicated by the MPT split information is equal to 2, and in a case where the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the second target block may be split into second sub-blocks of 2N × N size.

In addition, as another example, in the case where the size of the second target block is equal to 2N × 2N, and in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the splitting direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, the second target block may be split into N × 2N-sized second sub-blocks and N/2 × 2N-sized second sub-blocks. Also, in the case where the size of the second target block is equal to 2N × 2N, and in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3 and the splitting direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the second target block may be split into a second sub-block of 2N × N size and a second sub-block of 2N × N/2 size. In this case, for example, in the case where the splitting direction of the second target block indicated by the MPT splitting direction information corresponds to the vertical direction, among the second sub-blocks, the center second sub-block may be derived as a second sub-block of N × 2N size. Also, in the case where the splitting direction of the second target block indicated by the MPT splitting direction information corresponds to the horizontal direction, among the second sub-blocks, the center second sub-block may be derived as a second sub-block of 2N × N size. Meanwhile, in the case where the size of the second target block is equal to 2N × 2N, and in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3, and in the case where the split direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, the MPT split information may include MPT sub-split type information. In case that the value of the MPT sub-split type information is equal to 0, the MPT sub-split type information may indicate type 0. In case that the value of the MPT sub-split type information is equal to 1, the MPT sub-split type information may indicate type 1. And, in case that the value of the MPT sub-separation type information is equal to 2, the MPT sub-separation type information may indicate type 2. In case that the MPT sub-division type information indicates type 0, among the second sub-blocks, the left second sub-block may be derived as an N × 2N sized second sub-block. In case that the MPT sub-division type information indicates type 1, among the second sub-blocks, a central second sub-block may be derived as an N × 2N sized second sub-block. And, in case the MPT sub-split type information indicates type 2, among the second sub-blocks, the right second sub-block may be derived as an N × 2N sized second sub-block. In addition, in the case where the size of the second target block is equal to 2N × 2N, and in the case where the number of second sub-blocks indicated by the MPT split type information is equal to 3, and in the case where the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the MPT split information may include the MPT sub-split type information. In case that the value of the MPT sub-split type information is equal to 0, the MPT sub-split type information may indicate type 0. In case that the value of the MPT sub-split type information is equal to 1, the MPT sub-split type information may indicate type 1. And, in case that the value of the MPT sub-separation type information is equal to 2, the MPT sub-separation type information may indicate type 2. In case that the MPT sub-division type information indicates type 0, among the second sub-blocks, the upper side second sub-block may be derived as a 2N × N sized second sub-block. In case that the MPT sub-division type information indicates type 1, among the second sub-blocks, a central second sub-block may be derived as a 2N × N sized second sub-block. And, in case the MPT sub-division type information indicates type 2, among the second sub-blocks, a lower side second sub-block may be derived as a 2N × N sized second sub-block.

Here, in the case where the size of the second target block corresponds to 2N × 2N and the number of second sub-blocks indicated by the MPT split information is equal to 4, and in the case where the split direction of the second target block indicated by the MPT split direction information corresponds to the vertical direction, the second target block may be split into N/2 × 2N-sized second sub-blocks. And, in a case where the size of the second target block corresponds to 2N × 2N and the number along the second sub-block indicated by the MPT split information is equal to 4, and in a case where the split direction of the second target block indicated by the MPT split direction information corresponds to the horizontal direction, the second target block may be split into the second sub-blocks of 2N × N/2 size.

Meanwhile, the number of bits in the binarization string indicating the MPT separation information based on the separation type of the second target block may be variable. For example, a binarized string indicating MPT separation information most frequently applied to a separation type of a block among separation types within an input image (or target picture) may be derived as a binarized string having the smallest number of bits among the number of bits in the binarized string indicating the separation type. The binarized character string of the MPT separation information derived based on the separation type may be derived as shown in the above table 2, table 3, table 4, table 5, or table 6.

The decoding apparatus decodes the second sub-block (S940). The decoding device may decode the second sub-block. More specifically, the decoding apparatus may generate the prediction samples of the second sub-block by performing intra or inter prediction on the second sub-block. Thereafter, the decoding device may generate reconstructed (or restored) samples corresponding to the second sub-block based on the prediction samples, and may then generate a reconstructed picture based on the generated reconstructed samples.

Meanwhile, although not shown in the drawings, the decoding apparatus may directly use the prediction samples as reconstructed (or restored) samples according to the prediction mode, or the decoding apparatus may generate reconstructed samples by adding residual samples to the prediction samples. In the case where there are residual samples for the target block, the decoding apparatus may receive information on a residual of the target block, and the information on the residual may include information on a phase. The information on the residual may include transform coefficients corresponding to residual samples. The decoding apparatus may derive a residual sample (or a residual sample array) corresponding to the target block based on the residual information. The decoding device may generate reconstructed samples based on the predicted samples and the residual samples. And, the decoding device may then derive a reconstructed block or a reconstructed picture based on the recovered samples. Thereafter, as described above, the decoding apparatus may apply a loop filtering process such as a deblocking filtering and/or SAO process to the restored picture as necessary to enhance subjective/objective image quality.

According to the present disclosure as described above, a picture can be separated (or divided) into blocks having different shapes according to a multi-partition tree (MPT) structure, and by doing so, prediction efficiency can be improved, and overall coding efficiency can be enhanced.

In addition, according to the present disclosure, a picture may be separated (or divided) into blocks having different shapes according to a multi-partition tree (MPT) structure, and by doing so, transformation efficiency may be enhanced, and overall coding efficiency may be enhanced.

In the above embodiments, the method is described based on a flowchart having a series of steps or blocks. The present disclosure is not limited to the order of the above steps or blocks. As noted above, some steps or blocks may occur concurrently or in a different order than other steps or blocks. Further, those skilled in the art will appreciate that the steps illustrated in the above flowcharts are not exclusive, that other steps may be included, or that one or more steps in the flowcharts may be deleted without affecting the scope of the present disclosure.

The above-described method according to the present disclosure may be implemented in software. The encoding device and/or the decoding device according to the present disclosure may be included in a device that performs image processing, such as a television, a computer, a smart phone, a set-top box, or a display device.

When the embodiments of the present disclosure are implemented in software, the above-described methods may be implemented by modules (procedures, functions, and so on) that perform the above-described functions. Such modules may be stored in memory and executed by a processor. The memory may be internal or external to the processor, and may be coupled to the processor using a variety of well-known means. The processor may include an Application Specific Integrated Circuit (ASIC), other chipset, logic circuit, and/or data processing device. The memory may include ROM (read only memory), RAM (random access memory), flash memory, memory cards, storage media, and/or other storage devices.