APPARATUS AND METHOD FOR ENCODING A MOTION VECTOR BY USING A BASIC MOTION VECTOR AND APPARATUS AND METHOD FOR DECODING

Abstract

A method for decoding a move vector includes: determining at least one candidate block of a prediction move vector (PMV) used to determine a PMV of a current block; determining the availability of a move vector from at least the candidate block of the PMV; when there is a candidate block of the PMV that was determined to be unavailable, determining the PMV of the current block by using a default move vector (MV); and obtaining a move vector of the current block based on the determined PMV.

Description

APPARATUS AND METHOD FOR ENCODING MOTION VECTOR BY USING A BASIC MOTION VECTOR AND APPARATUS AND METHOD FOR DECODING Field of Invention The present disclosure relates to the fields of video encoding and decoding. More particularly, the present disclosure relates to a method and apparatus for encoding a motion vector of a video, and a method and apparatus for decoding a motion vector of a video. Background of the Invention In video encoding and decoding methods, for the purpose of encoding an image, a visual representation may be divided into macroblocks and each of the macroblocks may be encoded by using inter-prediction or intra-prediction. Inter-prediction refers to a method for compressing an image by removing temporal redundancy between visual representations, a representative example of which is motion estimation coding. In motion estimation coding, each block of a current visual representation is predicted by using at least one reference visual representation. A reference block that is most similar to a block Reí 350519 current is found within a predetermined search range by using a predetermined evaluation function. A current block is predicted based on a reference block, and a residual block is encoded. This residual block is obtained by subtracting a prediction block generated as a prediction result from the current block. In this case, to achieve more accurate prediction, interpolation is performed within a search interval of the reference visual representation. Sub-pel-unit pixels smaller than integer-pel-unit pixels can be generated, and interprediction can be performed on the generated sub-pel-unit pixels. In a codec such as H.264 Advanced Video Coding (AVC) and High Efficiency Video Coding (HEVC), for the purpose of predicting a motion vector of a current block, a motion vector of previously coded blocks adjacent to the current block or blocks included in a previously coded visual representation is used as a prediction motion vector of the current block. Summary of the Invention SOLUTION TO THE PROBLEM A method for decoding a motion vector, according to one embodiment, may include: determining at least one prediction motion vector (PMV) candidate block used to determine a PMV of a current block; determining the availability of a motion vector of at least the PMV candidate block; when there is a PMV candidate block that is determined to be unavailable, determining the PMV of the current block by using a default motion vector (MV); and obtaining a motion vector of the current block based on the determined PMV. ADVANTAGEOUS EFFECTS OF THE DESCRIPTION An apparatus and method for encoding a motion vector and an apparatus and method for decoding a motion vector according to an embodiment may determine an accurate prediction motion vector for a current block by using a default motion vector, thereby reducing a bit rate for representing a residual motion vector and improving quality of a reconstructed image. Brief Description of the Figures A brief explanation of each figure is provided to more fully understand the associated figures. FIGURE 1 is a block diagram of an image decoding apparatus for decoding an image based on at least one of block shape information and division shape information, according to an embodiment. FIGURE 2 is a block diagram of an image coding apparatus for coding an image based on at least one of block shape information and division shape information, according to an embodiment. FIGURE 3 illustrates a process in which a current coding unit is divided to determine at least one coding unit, according to an embodiment. FIGURE 4 illustrates a process for determining at least one coding unit by partitioning a non-square coding unit, in accordance with one embodiment. FIGURE 5 illustrates a process for dividing a coding unit based on at least one of block shape information and partition shape information, according to an embodiment. FIGURE 6 illustrates a method for determining a predetermined coding unit from among an odd number of coding units, according to one embodiment. FIGURE 7 illustrates a processing order of a plurality of coding units when the plurality of coding units are determined by dividing a current coding unit, according to an embodiment. FIGURE 8 illustrates a process for determining that a current coding unit should be split into an odd number of coding units, when the coding units are not processable in a predetermined order, according to an embodiment. FIGURE 9 illustrates a process for determining at least one coding unit by dividing a first coding unit, according to one embodiment. FIGURE 10 illustrates that a shape into which a second coding unit is divisible is restricted when the second coding unit having a non-square shape, which is determined by dividing a first coding unit, satisfies a predetermined condition, according to an embodiment. FIGURE 11 illustrates a process for dividing a square coding unit when the division shape information indicates that the square coding unit should not be divided into four square coding units, according to an embodiment. FIGURE 12 illustrates that a processing order among a plurality of coding units may be changed depending on a process for dividing a coding unit, according to an embodiment. FIGURE 13 illustrates a process for determining a depth of a coding unit as a shape and size of the coding unit change, when the coding unit is repeatedly divided such that a plurality of coding units are determined, according to an embodiment. FIGURE 14 illustrates depths that are determinable based on shapes and sizes of coding units, and part indices (PIDs) to distinguish coding units, according to one embodiment. FIGURE 15 illustrates that a plurality of coding units are determined based on a plurality of predetermined data units that are included in a visual representation, according to an embodiment. FIGURE 16 illustrates a processing block that serves as a criterion for determining an order of determining reference coding units that are included in a visual representation, according to a modality. FIGURE 17 illustrates coding units determinable by visual representation when a combination of forms into which a coding unit is divisible is different by visual representation, according to a modality. FIGURE 18 illustrates various forms of a coding unit determinable based on division shape information representable as a binary code, according to one embodiment. FIGURE 19 illustrates other forms of a coding unit determinable based on division shape information representable as a binary code, according to one embodiment. FIGURE 20 is a block diagram of an image encoding and decoding system for performing loop filtering. FIGURE 21 illustrates an example of filter units included in the larger coding unit and filtering performance information of a filter unit, according to one embodiment. FIGURE 22 illustrates a process for performing a combination or division between determined coding units according to a predetermined coding method, according to one embodiment. FIGURE 23 illustrates an index according to a Z-scan order of a coding unit, according to one embodiment. FIGURE 24 is a diagram of a reference sample for intra-prediction of a coding unit, according to one modality. FIGURE 25 is a block diagram illustrating a configuration of a motion vector decoding apparatus according to one embodiment. FIGURE 26 is a flowchart for describing a method for decoding a motion vector, according to an embodiment. FIGURE 27 is a block diagram illustrating a configuration of a motion vector coding apparatus according to one embodiment. FIGURE 28 is a flowchart for describing a method for encoding a motion vector, according to an embodiment. FIGURE 29 is a diagram illustrating spatial blocks and temporal blocks associated with a current block. FIGURE 30 is a diagram illustrating default motion vector (MV) candidate blocks for determining a default MV. FIGURES 31 and 32 are diagrams illustrating prediction motion vector (PMV) candidate blocks for determining a PMV. FIGS. 33A-33D are diagrams illustrating pixel positions that may be indicated by motion vectors according to a 1 / 4 pixel unit motion vector resolution (MVR), a 1 / 2 pixel unit MVR, a 1 pixel unit MVR, and a 2 pixel unit MVR when a minimum MVR that is selectable for a current block is the 1 / 4 pixel unit MVR. FIGURES 34 and 35 are graphs to describe a method for setting a default MV. FIGURE 36 is a diagram illustrating an exemplary syntax for describing a process for obtaining an MVR index of a current block. Detailed Description of the Invention A method for decoding a motion vector, according to one embodiment, may include: determining at least one prediction motion vector (PMV) candidate block used to determine a PMV of a current block; determining the availability of a motion vector of at least the PMV candidate block; when there is a PMV candidate block that was determined to be unavailable, determining the PMV of the current block by using a default motion vector (MV); and obtaining a motion vector of the current block based on the determined PMV. The method may further include determining the default MV based on motion vectors of a plurality of default MV candidate blocks associated with the current block. Determining the default MV may include: sequentially determining, based on a priority order, whether motion vectors exist with respect to the plurality of candidate default MV blocks; and determining the default MV based on the motion vectors of the plurality of candidate default MV blocks, based on an order in which the motion vectors are identified. The method may further include determining a motion vector derived via decoder-side motion vector derivation (DMVD) as the default MV. Determining the default MV may include determining the default MV based on the motion vector of the default MV candidate block having a reference picture index that is the same as a reference picture index of the current block. Determining the default MV may include determining the default MV based on a motion vector of a default MV candidate block having a reference picture index that is the same as a reference picture index of the current block. Determining the default MV may include: selecting at least one default MV candidate block based on the motion vector sizes of the plurality of default MV candidate blocks; and determining the default MV based on the motion vector of at least the selected default MV candidate block. The selection of at least the default MV candidate block may include selecting a default MV candidate block having the largest motion vector or the smallest motion vector from among the plurality of default MV candidate blocks. Determining the default MV may include determining the default MV based on an average value or an intermediate value of the motion vectors of the plurality of default MV candidate blocks. Determining the default MV may include determining the default MV by using a motion vector of a default MV candidate block selected from the plurality of default MV candidate blocks, the default MV candidate block being selected based on the number of times in which the default MV candidate block is determined to be a PMV in a previously decoded visual representation, a previously decoded slice, or the previously decoded largest coding unit. The determination of the default MV may include iviA / a / zuzo / uii ooo determining a plurality of default MVs each corresponding to an address, from the plurality of candidate blocks of default MVs each being located at a different address from each other, based on the current block. The plurality of default MVs may include a first default MV and a second default MV, and determining the default MV may include determining the first default MV by using a motion vector of a default MV candidate block located in a first direction based on the current block, and determining the second default MV by using a motion vector of a default MV candidate block located in a second direction based on the current block. Determining the PMV of the current block may include: when at least the PMV candidate block includes a PMV candidate block located in the first direction based on the current block and a PMV candidate block located in the second direction based on the current block, assigning the first default MV as the motion vector of the PMV candidate block located in the first direction, when there is no motion vector in the PMV candidate block located in the first direction; and assigning the second default MV as the motion vector of the PMV candidate block located in the second direction, when there is no motion vector in the PMV candidate block located in the second direction to determine the PMV of the current block. The method may further include determining a motion vector resolution with respect to the current block, and determining the PMV of the current block may include, when the motion vector does not exist in at least the determined PMV candidate block that is used for the PMV according to the motion vector resolution, based on the result of determining the availability of the motion vector, assigning the default MV to the PMV candidate block with respect to which the motion vector does not exist. Determining the PMV of the current block may include: setting the default MV based on the motion vector resolution of the current block; and determining the PMV of the current block based on the set default MV. Determining the PMV of the current block may include: based on the result of determining the availability of the motion vector, constructing a prediction candidate list from the motion vector of at least the PMV candidate block; when the number of prediction candidates included in the IVIA / a / ZUzí J / UII ooo prediction candidate list is less than a predetermined number, add the default MV to the prediction candidate list such that the number of prediction candidates becomes the predetermined number; and determine the PMV of the current block based on the prediction candidates included in the prediction candidate list. Determining the PMV of the current block may include assigning the default MV to a PMV candidate block relative to which there is no motion vector among at least the PMV candidate block at a predetermined location. An apparatus for decoding a motion vector, according to one embodiment, includes: a default motion vector determiner configured to determine a default motion vector (MV) of a current block; and a prediction decoder configured to determine the availability of at least one prediction motion vector (PMV) candidate block used to determine a PMV of the current block, and when there is a PMV candidate block that was determined to be unavailable, configured to determine the PMV of the current block by using the determined default MV and obtain a motion vector of the current block based on the determined PMV. iviA / a / zuzo / uii ooo A method for encoding a motion vector, according to one embodiment, includes: determining the availability of a motion vector from at least one prediction motion vector (PMV) candidate block used to determine a PMV of a current block; and when there is a PMV candidate block that was determined to be unavailable, determining the PMV of the current block by using a default motion vector (MV). Since the present disclosure allows for various changes and numerous embodiments, exemplary embodiments will be illustrated in the figures and set forth in detail in the written description. However, this is not intended to limit the present disclosure to particular modes of practice, and it should be appreciated that all changes, equivalents, and replacements that do not depart from the spirit and technical scope of the present disclosure are encompassed by the present disclosure. In the discussion of the present description, certain detailed explanations of the related art are omitted because they are considered likely to unnecessarily obscure the essence of the present description. Also, the numerals (e.g., first and second) used in the discussion of the embodiments of the description are intended only to distinguish one component from another. iviA / a / zuzo / uii ooo When a component is referred to as being connected to or accessed by any other component, it should be understood that the component may be connected or accessed directly to and by the other component, but another new component may also be interposed between them, unless specifically stated otherwise. With respect to an element with a suffix such as "unit" or "module," two or more elements may be combined into one element, or one element may be divided into two or more elements according to functions. Furthermore, each of the respective components described below may additionally perform some or all of the functions among functions performed by other components in addition to a primary function performed by each component, and some functions among primary functions performed by the respective components may be performed exclusively by other components. Also, the term image or visual representation used in this document may refer to a still image of an image, or a moving image, that is, an image itself. Also, the term "sample" used in this document refers to data that is assigned to a sampling location in an image and must be processed. For example, pixels in an image in a spatial domain or transform coefficients in a transform domain can be samples. A unit that includes one or more samples can be defined as a block. Also, the term current block used in this document may refer to a block of the larger coding unit, a coding unit, a prediction unit, or a transform unit of a current image being encoded or decoded. Also, the term motion vector resolution (MVR) used in this document can refer to the accuracy of a pixel position that can be indicated by a motion vector determined through inter-prediction between pixels included in a reference image (or an interpolated reference image). When an MVR has a unit of N pixels (N being a rational number), it means that a motion vector can have the accuracy of a unit of N pixels.For example, a 1 / 4 pixel unit MVR may mean that a motion vector may indicate a pixel position of a 1 / 4 pixel unit (i.e., a sub-pixel unit) in an interpolated reference image, and a 1 pixel MVR of one unit may mean that a motion vector may indicate a pixel position corresponding to a 1 pixel unit (i.e., a integer unit of pixel) in an interpolated reference image. Also, the term candidate MVR used in this document refers to one or more MVRs that can be selected as an MVR of a block, and the term candidate block refers to one or more blocks that are assigned to a candidate MVR and can be used as a block for a prediction motion vector of a block that is inter-predicted. Also, the term pixel unit used in this document can be used interchangeably with the terms pixel precision and pixel accuracy. Hereinafter, an image coding method and apparatus and an image decoding method and apparatus based on a coding unit and a transform unit according to the tree structure according to an embodiment will be described with reference to FIGS. 1 to 24. An image coding apparatus 200 and an image decoding apparatus 100 that are described with reference to FIGS. 1 to 24 may respectively include a motion vector coding apparatus 2700 and a motion vector decoding apparatus 2500 that are described with reference to FIGS. FIGURES 25 to 36. FIGURE 1 is a block diagram of the image decoding apparatus 100 for decoding an image based on at least one of block shape information and division shape information, according to an embodiment. 1 , according to one embodiment, the image decoding apparatus 100 may include the bit stream acquirer 110 for obtaining predetermined information such as split shape information or block shape information from a bit stream, and the decoder 120 for decoding an image by using the obtained information. When the bit stream acquirer 110 of the image decoding apparatus 100 obtains at least one of the block shape information and the split shape information according to one embodiment, the decoder 120 of the image decoding apparatus 100 may determine at least one coding unit for splitting an image based on at least one of the block shape information and the split shape information. According to one embodiment, the decoder 120 of the image decoding apparatus 100 may determine a shape of the coding unit based on the block shape information. For example, the block shape information may include information indicating whether the coding unit has a square shape or a non-square shape. The decoder 120 may determine the shape of the coding unit by using the block shape information. According to one embodiment, the decoder 120 may determine a manner in which a coding unit is to be divided based on the division manner information. For example, the division manner information may indicate information about a shape of at least one coding unit included in the coding unit. According to one embodiment, the decoder 120 may determine whether or not the coding unit is divided according to the division shape information. The division shape information may include information about at least the coding unit included in the coding unit, and when the division shape information indicates that only one coding unit is included in the coding unit or is not divided, the decoder 120 may determine that the coding unit including the division shape information is not divided. When the division shape information indicates that the coding unit is divided into a plurality of coding units, the decoder 120 may divide the coding unit into the plurality of coding units included in the coding unit based on the division shape information. According to one embodiment, the division shape information may indicate the number of coding units into which the coding unit is to be divided or a direction in which the coding unit is to be divided. For example, the division shape information may indicate that the coding unit is divided in at least one direction between a vertical direction and a horizontal direction or is not divided. FIGURE 3 illustrates a process in which the image decoding apparatus 100 determines at least one coding unit by dividing a current coding unit according to a mode. A block shape may include 4Nx4N, 4Nx2N, 2Nx4N, 4NxN, or Nx4N. N may be a positive integer. Block shape information is information indicating at least one of a ratio or size of a shape, a direction, a width, and a height of a coding unit. The shape of the coding unit may include a square shape and a non-square shape. When the width and height of the coding unit are the same (4Nx4N), the image decoding apparatus 100 may determine the block shape information of the coding unit as a square shape. The image decoding apparatus 100 may determine the shape of the coding unit as a non-square shape. When the width and height of the coding unit are different from each other (4Nx2N, 2Nx4N, 4NxN or Nx4N), the image decoding apparatus 100 may determine the block shape information of the coding unit as a non-square shape. When the shape of the coding unit is a non-square shape, the image decoding apparatus 100 may determine the ratio of the width and the height in the block shape information of the coding unit as at least one of 1:2, 2:1, 1:4, 4:1, 1:8 and 8:1. Also, the image decoding apparatus 100 may determine whether the coding unit is a horizontal direction or a vertical direction, based on a length of the width and a length of the height of the coding unit.Also, the image decoding apparatus 100 may determine the size of the coding unit, based on at least one of the length of the width, the length of the height and an area of ​​the coding unit. According to one embodiment, the image decoding apparatus 100 may determine a shape of the coding unit by using the block shape information, and may determine into what shape the coding unit is divided by using information about a division shape mode. That is, a coding unit division method indicated by the information about the division shape mode may be determined according to what block shape is indicated by the block shape information used by the image decoding apparatus 100. The image decoding apparatus 100 may obtain information about the splitting shape mode of a bit stream. However, the present disclosure is not limited thereto, and the image decoding apparatus 100 and the image coding apparatus 200 may obtain information about the pre-promised splitting shape mode based on the block shape information. The image decoding apparatus 100 may obtain information about the pre-promised splitting shape mode for the largest coding unit or the smallest coding unit. For example, the image decoding apparatus 100 may determine that a size of the largest coding unit is 256x256. The image decoding apparatus 100 may determine information about the pre-promised splitting shape mode by using quadruple splitting.Quadruple division is a division shape mode in which the width and height of the coding unit are divided in half. The image decoding apparatus 100 may obtain the coding unit having a size of 128x128 from the larger coding unit having a size of 256x256 based on the information about the division shape mode. Also, the image decoding apparatus 100 may determine that a size of the smaller coding unit is 4x4. The image decoding apparatus 100 may obtain the information about the division shape mode indicating not to perform division for the smaller coding unit. According to one embodiment, the image decoding apparatus 100 may use the block shape information indicating that the current coding unit has a square shape. For example, the image decoding apparatus 100 may determine whether to not divide a square coding unit, whether to divide the square coding unit vertically, whether to divide the square coding unit horizontally, or whether to divide the square coding unit into four coding units, based on the information about the division shape mode.With reference to FIG. 3, when the block shape information of a current coding unit 300 indicates a square shape, the decoder 120 may determine that a coding unit 310a having the same size as the current coding unit 300 is not divided, based on the information about the division shape mode indicating that division is not performed, or may determine the divided coding units 310b, 310c, or 310d based on the information about the division shape mode indicating a predetermined division method. 3 , according to one embodiment, the image decoding apparatus 100 may determine two coding units 310b obtained by vertically dividing the current coding unit 300, based on information about the division shape mode indicating to perform division vertically. The image decoding apparatus 100 may determine two coding units 310c obtained by horizontally dividing the current coding unit 300, based on information about the division shape mode indicating to perform division horizontally. The image decoding apparatus 100 may determine four coding units 310d obtained by vertically and horizontally dividing the current coding unit 300, with IVIA / a / ZUzí J / UII ooo based on information about the splitting shape mode that indicates performing vertical and horizontal splitting. However, the splitting methods for the square coding unit are not limited to the methods described above, and the splitting shape mode information may indicate various methods. The predetermined splitting methods for splitting the square coding unit will be described in detail later in relation to various embodiments. FIGURE 4 illustrates a process, performed by the image decoding apparatus 100, for determining at least one coding unit by dividing a non-square coding unit, according to an embodiment. According to one embodiment, the image decoding apparatus 100 may use block shape information indicating that a current coding unit has a non-square shape. The image decoding apparatus 100 may determine whether to not divide the current non-square coding unit or to divide the current non-square coding unit by using a predetermined division method based on information about a division shape mode. With reference to FIG. 4 , when the block shape information of a current coding unit 400 or 450 indicates IVIA / a / ZUzíó / UII or a non-square shape, the image decoding apparatus 100 may determine that a coding unit 410 or 460 having the same size as the current coding unit 400 or 450 is not divided, based on the information about the division shape mode indicating not to perform the division, or may determine divided coding units 420a and 420b, 430a to 430c, 470a and 470b, or 480a to 480c based on the information about the division shape mode indicating a predetermined division method. The predetermined division methods for dividing a non-square coding unit will be described in detail later in relation to various embodiments. According to one embodiment, the image decoding apparatus 100 may determine a method of dividing a coding unit by using the information about the division shape mode, and in this case, the division shape information may indicate the number of one or more coding units generated by dividing the coding unit. Referring to FIG. 4 , when the information about the division shape mode indicates dividing the current coding unit 400 or 450 into two coding units, the image decoding apparatus 100 may determine two coding units 420a and 420b, or 470a and 470b included in the coding unit. IVIA / a / ZUzíó / UII ooo current coding unit 400 or 450, by splitting the current coding unit 400 or 450 based on the information about the splitting shape mode. According to one embodiment, when the image decoding apparatus 100 divides the current non-square coding unit 400 or 450 based on the information about the division shape mode, the location of a long side of the current non-square coding unit 400 or 450 may be considered. For example, the image decoding apparatus 100 may determine a plurality of coding units by dividing the long side of the current coding unit 400 or 450, taking into account the shape of the current coding unit 400 or 450. According to one embodiment, when the information about the splitting manner mode indicates to split a coding unit into an odd number of blocks, the image decoding apparatus 100 may determine an odd number of coding units included in the current coding unit 400 or 450. For example, when the information about the splitting manner mode indicates to split the current coding unit 400 or 450 into three coding units, the image decoding apparatus 100 may split the current coding unit 400 or 450 into three coding units 430a, 430b and 430c iviA / a / zuzo / uii ooo or 480a, 480b and 480c. According to one embodiment, a ratio of a width to a height of the current coding unit 400 or 450 may be 4:1 or 1:4. When the ratio of the width to the height is 4:1, a length of the width is larger than a length of the height, and thus the block shape information may be horizontal. When the ratio of the width to the height is 1:4, a length of the width is smaller than a length of the height, and thus the block shape information may be vertical. The image decoding apparatus 100 may determine to divide the current coding unit into an odd number of blocks based on information about the division shape mode. Also, the image decoding apparatus 100 may determine a division direction of the current coding unit 400 or 450 based on the block shape information of the current coding unit 400 or 450.For example, when the current coding unit 400 is in a vertical direction, the image decoding apparatus 100 may horizontally divide the current coding unit 400 and may determine the coding units 430a, 430b, and 430c. Also, when the current coding unit 450 is in a horizontal direction, the image decoding apparatus 100. QQQI can vertically divide the current coding unit 450 and can determine the coding units 480a, 480b and 480c. According to one embodiment, the image decoding apparatus 100 may determine an odd number of coding units included in the current coding unit 400 or 450, and the sizes of all of the determined coding units may not be the same. For example, a predetermined coding unit 430b or 480b among the determined odd number of coding units 430a, 430b and 430c, or 480a, 480b and 480c may have a size different from the size of the other coding units 430a and 430c, or 480a and 480c. That is, the coding units which can be determined by dividing the current coding unit 400 or 450 may have multiple sizes, and in some cases, the entire odd number of coding units 430a, 430b, and 430c, or 480a, 480b, and 480c may have different sizes. According to one embodiment, when the information about the splitting manner mode indicates splitting a coding unit into an odd number of blocks, the image decoding apparatus 100 may determine an odd number of coding units included in the current coding unit 400 or 450, and may place a predetermined restriction on at least one coding unit from among the odd number of coding units generated by splitting the current coding unit 400 or 450.4, the image decoding apparatus 100 may allow a decoding method of the coding unit 430b or 480b to be different from that of the other coding units 430a and 430c, or 480a and 480c, wherein the coding unit 430b or 480b is at a central location among the three coding units 430a, 430b and 430c, or 480a, 480b and 480c generated by dividing the current coding unit 400 or 450. For example, the image decoding apparatus 100 may restrict the coding unit 430b or 480b at the central location to no longer be divided or to be divided only a predetermined number of times, as opposed to the other coding units 430a and 430c, or 480a and 480c. FIGURE 5 illustrates a process, performed by the image decoding apparatus 100, for dividing a coding unit based on at least one of block shape information and information about a division shape mode, according to an embodiment. According to one embodiment, the image decoding apparatus 100 may determine whether to divide or not divide a first square coding unit 500 into 400 coding units, based on at least one of the block shape information and the information about the division shape mode. According to one embodiment, when the information about the division shape mode indicates dividing the first coding unit 500 in a horizontal direction, the image decoding apparatus 100 may determine a second coding unit 510 when dividing the first coding unit 500 in a horizontal direction. A first coding unit, a second coding unit, and a third coding unit used according to one embodiment are terms used to understand a relationship before and after dividing a coding unit.For example, a second coding unit may be determined by dividing a first coding unit, and a third coding unit may be determined by dividing the second coding unit. It will be understood that a relationship between the first coding unit, the second coding unit, and the third coding unit follows the descriptions above. According to one embodiment, the image decoding apparatus 100 may determine whether to divide or not divide the determined second coding unit 510 into coding units, based on at least one of the block shape information and the information about the splitting shape mode. With reference to FIG. 5, the image decoding apparatus 100 may divide or not divide the second non-square coding unit 510, which is determined by dividing the first coding unit 500, into one or more third coding units 520a, or 520b, 520c, and 520d based on at least one of the block shape information and the information about the splitting shape mode.The image decoding apparatus 100 may obtain at least one of the block shape information and the information about the splitting shape mode, and may split a plurality of second coding units in various ways (e.g., 510) by splitting the first coding unit 500, based on at least the information obtained from among the block shape information and the information about the splitting shape mode, and the second coding unit 510 may be split by using the method of splitting the first coding unit 500, based on at least one of the block shape information and the information about the splitting shape mode.According to one embodiment, when the first coding unit 500 is divided into the second coding units 510 based on at least one of the block shape information and the information about the splitting shape mode of the first unit. IVIA / a / ZUzí J / UII ooo coding 500, the second coding unit 510 may also be divided into third coding units 520a, or 520b, 520c, and 520d based on at least one of the block shape information and information about the splitting shape mode of the second coding unit 510. That is, a coding unit may be repeatedly divided based on at least one of the block shape information and information about the splitting shape mode of each coding unit. Therefore, a square coding unit may be determined by dividing a non-square coding unit, and a non-square coding unit may be determined by repeatedly dividing the square coding unit. 5 , a predetermined coding unit from among an odd number of third coding units 520b, 520c, and 520d determined by dividing the second non-square coding unit 510 (e.g., a coding unit at a center location or a square coding unit) may be repeatedly divided. According to one embodiment, the third square coding unit 520b from among the odd number of third coding units 520b, 520c, and 520d may be divided in a horizontal direction into a plurality of fourth coding units. A fourth non-square coding unit 530b or 530d from among the plurality of fourth coding units 530a, 530b, 530c, and 530d may be divided into a plurality of coding units. For example, the fourth non-square coding unit 530 or 530d can be divided again into an odd number of coding units.A method that can be used to repeatedly divide a coding unit will be described below in relation to several embodiments. According to one embodiment, the image decoding apparatus 100 may divide each of the third coding units 520a, or 520b, 520c, and 520d into coding units, based on at least one of the block shape information and the information about the division shape mode. Also, the image decoding apparatus 100 may determine not to divide the second coding unit 510 based on at least one of the block shape information and the information about the division shape mode. According to one embodiment, the image decoding apparatus 100 may divide the second non-square coding unit 510 into the odd number of third coding units 520b, 520c, and 520d. The image decoding apparatus 100 may place a predetermined restriction on a predetermined third coding unit of IVIA / a / ZUzí J / UII ooo among the odd number of third coding units 520b, 520c and 520d. For example, the image decoding apparatus 100 may restrict the third coding unit 520c at a central location among the odd number of third coding units 520b, 520c and 520d so that it is no longer divided or is divided an adjustable number of times. 5, the image decoding apparatus 100 may restrict the third coding unit 520c, which is at the center location among the odd number of third coding units 520b, 520c, and 520d included in the second non-square coding unit 510, to no longer be divided, to be divided by using a predetermined division method (e.g., divided into only four coding units or divided by using a method of dividing the second coding unit 510), or to be divided only a predetermined number of times (e.g., divided only n times (where n>0)).However, the restrictions on the third coding unit 520c at the central location are not limited to the examples described above, and may include various restrictions for decoding the third coding unit 520c at the central location in a manner iviA / a / zuzo / uii ooo different from the other third coding units 520b and 520d. According to an embodiment, the image decoding apparatus 100 may obtain at least one of block shape information and information about the splitting shape mode, which is used to split a current coding unit, from a predetermined location in the current coding unit. FIGURE 6 illustrates a method, performed by the image decoding apparatus 100, for determining a predetermined coding unit from among an odd number of coding units, according to an embodiment. 6 , at least one of the block shape information and information about a split shape mode of a current coding unit 600 or 650 may be obtained from a sample at a predetermined location among a plurality of samples included in the current coding unit 600 or 650 (e.g., a sample 640 or 690 at a center location). However, the predetermined location in the current coding unit 600, from which at least one of the block shape information and information about the split shape mode may be obtained, is not limited to the center location in the iviA / a / zuzo / uii ooo FIGURE 6 , and may include a plurality of locations included in the current coding unit 600 (e.g., top, bottom, left, right, top left, bottom left, top right, and bottom right locations). The image decoding apparatus 100 may obtain at least one of the block shape information and the information about the splitting shape mode from the predetermined location, and may determine whether or not to split the current coding unit into coding units of a plurality of shapes and sizes. According to one embodiment, when the current coding unit is divided into a predetermined number of coding units, the image decoding apparatus 100 may select one of the coding units. Various methods may be used to select one of a plurality of coding units, as will be described later in relation to various embodiments. According to one embodiment, the image decoding apparatus 100 may divide the current coding unit into a plurality of coding units, and may determine a coding unit at a predetermined location. According to one embodiment, the image decoding apparatus 100 may use information indicating locations of an odd number of coding units to determine a coding unit at a central location among the odd number of coding units. Referring to FIG. 6, the image decoding apparatus 100 may determine an odd number of coding units 620a, 620b, and 620c or an odd number of coding units 660a, 660b, and 660c by dividing the current coding unit 600 or the current coding unit 650. The image decoding apparatus 100 may determine the coding unit 620b at a central location or the coding unit 660b at a central location by using information about locations of the odd number of coding units 620a, 620b, and 620c or the odd number of coding units 660a, 660b, and 660c.For example, the image decoding apparatus 100 may determine the coding unit 620b at the center location by determining the locations of the coding units 620a, 620b, and 620c based on information indicating locations of predetermined samples included in the coding units 620a, 620b, and 620c. In detail, the image decoding apparatus 100 may determine the coding unit 620b at the center location by determining the locations of the coding units 620a, 620b, and 620c based on information indicating locations of the. IVIA / a / ZUzíó / UII ooo upper left samples 630a, 630b and 630c of coding units 620a, 620b and 620c. According to one embodiment, the information indicating the locations of the upper left samples 630a, 630b and 630c, which are included in the coding units 620a, 620b and 620c, respectively, may include information about locations or coordinates of the coding units 620a, 620b and 620c. 620c in a visual representation. According to one embodiment, the information indicating the locations of the upper left samples 630a, 630b and 630c, which are included in the coding units 620a, 620b and 620c, respectively, may include information indicating widths or heights of the coding units 620a, 620b and 620c included in the current coding unit 600, and the widths or heights may correspond to information indicating differences between the coordinates of the coding units 620a, 620b and 620c in the visual representation. That is, the image decoding apparatus 100 can determine the coding unit 620b at the center location by directly using the information about the locations or coordinates of the coding units 620a, 620b and 620c. 620c in the visual representation, or by using the IVIA / a / ZUzí J / UII ooo information about the widths or heights of the coding units, which correspond to the difference values ​​between the coordinates. According to one embodiment, the information indicating the location of the upper left sample 630a of the upper coding unit 620a may include coordinates (xa, ya), the information indicating the location of the upper left sample 630b of the intermediate coding unit 620b may include coordinates (xb, yb), and the information indicating the location of the upper left sample 630c of the lower coding unit 620c may include coordinates (xc, ye). The image decoding apparatus 100 may determine the intermediate coding unit 620b by using the coordinates of the upper left samples 630a, 630b and 630c which are included in the coding units 620a, 620b and 620c, respectively.For example, when the coordinates of the upper left samples 630a, 630b, and 630c are sorted in ascending or descending order, the coding unit 620b including the coordinates (xb, yb) of the sample 630b at a center location may be determined as a coding unit at a center location from among the coding units 620a, 620b, and 620c determined by dividing the current coding unit 600.However, the coordinates indicating the locations of the upper left samples 630a, 630b, and 630c may include coordinates indicating absolute locations in the visual representation, or may use coordinates (dxb, dyb) indicating a relative location of the upper left sample 630b of the middle coding unit 620b and coordinates (dxc, dyc) indicating a relative location of the upper left sample 630c of the lower coding unit 620c with reference to the location of the upper left sample 630a of the upper coding unit 620a.Also, a method for determining a coding unit at a predetermined location by using coordinates of a sample included in the coding unit as information indicating a location of the sample is not limited to the method described above, and may include various arithmetic methods capable of using the coordinates of the sample. According to one embodiment, the image decoding apparatus 100 may divide the current coding unit 600 into the plurality of coding units 620a, 620b, and 620c, and may select one of the coding units 620a, 620b, and 620c based on a predetermined criterion. For example, the image decoding apparatus 100 may select the coding unit 620b having a size different from that of the others from among the coding units 620a, 620b, and 620c. According to one embodiment, the image decoding apparatus 100 may determine the widths or heights of the coding units 620a, 620b, and 620c by using the coordinates (xa, ya) indicating the location of the upper left sample 630a of the upper coding unit 620a, the coordinates (xb, yb) indicating the location of the upper left sample 630b of the middle coding unit 620b, and the coordinates (xc, ye) indicating the location of the upper left sample 630c of the lower coding unit 620c. The image decoding apparatus 100 may determine the respective sizes of the coding units 620a, 620b, and 620c by using the coordinates (xa, ya), (xb, yb), and (xc, ye) indicating the locations of the coding units 620a, 620b, and 620c.According to one embodiment, the image decoding apparatus 100 may determine the width of the upper coding unit 620a to be a width of the current coding unit 600. The image decoding apparatus 100 may determine the height of the upper coding unit 620a to be ybya. According to one embodiment, the image decoding apparatus 100 may determine the width iviA / a / zuzo / uii ooo of the intermediate coding unit 620b to be a width of the current coding unit 600. The image decoding apparatus 100 may determine the height of the intermediate coding unit 620b to be yc-yb.According to one embodiment, the image decoding apparatus 100 may determine the width or height of the lower coding unit 620c by using the width or height of the current coding unit 600 or the widths or heights of the upper and middle coding units 620a and 620b. The image decoding apparatus 100 may determine a coding unit, which has a size different from that of the others, based on the determined widths and heights of the coding units 620a to 620c. With reference to FIG. 6, the image decoding apparatus 100 may determine the middle coding unit 620b, which has a size different from the size of the upper and lower coding units 620a and 620c, as the coding unit of the predetermined location.However, the above-described method performed by the image decoding apparatus 100 for determining a coding unit having a size different from the size of other coding units corresponds to an example for determining a coding unit at a predetermined location by using the coding unit sizes determined based on sample coordinates, and thus various methods can be used for determining a coding unit at a predetermined location by comparing the coding unit sizes determined based on predetermined sample coordinates. The image decoding apparatus 100 may determine a width or a height of each of the coding units 660a, 660b, and 660c by using the coordinates (xd, yd) which are information indicating a location of an upper left sample 670a of the left coding unit 660a, the coordinates (xe, ye) which are information indicating a location of an upper left sample 670b of the middle coding unit 660b, and the coordinates (xf, yf) which are information indicating a location of an upper left sample 670c of the right coding unit 660c. The image decoding apparatus 100 may determine sizes of the coding units 660a, 660b, and 660c by using the coordinates (xd, yd), (xe, ye), and (xf, yf) indicating locations of the coding units 660a, 660b, and 660c. According to one embodiment, the image decoding apparatus 100 may determine the width IVIA / a / ZUzí J / UII ooo of the left coding unit 660a to be xexd. The image decoding apparatus 100 may determine the height of the left coding unit 660a as the height of the current coding unit 650. According to one embodiment, the image decoding apparatus 100 may determine the width of the intermediate coding unit 660b to be xf-xe. The image decoding apparatus 100 may determine the height of the intermediate coding unit 660b to be the height of the current coding unit 600. According to one embodiment, the image decoding apparatus 100 may determine the width or height of the right coding unit 660c by using the width or height of the current coding unit 650 and the width and height of the left coding unit 660a and the intermediate coding unit 660b.The image decoding apparatus 100 may determine a coding unit having a size different from that of the others based on the determined widths and heights of the coding units 660a, 660b, and 660c. Referring to FIG. 6, the image decoding apparatus 100 may determine the intermediate coding unit 660b having a size different from the size of the left coding unit iviA / a / zuzo / uii ooo. 660a and the right coding unit 660c, as the coding unit of the predetermined location. However, the method described above, performed by the image decoding apparatus 100, for determining a coding unit having a size different from the size of the other coding units corresponds to only one example of determining a coding unit at a predetermined location by using the coding unit sizes, which are determined based on sample coordinates, and in this way, various methods can be used to determine a coding unit at a predetermined location by comparing the coding unit sizes, which are determined based on predetermined sample coordinates. However, the sample locations considered to determine coding unit locations are not limited to the upper left locations described above, and information about arbitrary sample locations included in the coding units can be used. According to one embodiment, the image decoding apparatus 100 may select a coding unit at a predetermined location from among an odd number of coding units determined by the image decoding apparatus 100. IVIA / a / ZUzí J / UII ooo dividing the current coding unit, considering the shape of the current coding unit. For example, when the current coding unit has a non-square shape, a width of which is larger than a height, the image decoding apparatus 100 may determine the coding unit at the predetermined location in a horizontal direction. That is, the image decoding apparatus 100 may determine one of the coding units at different locations in a horizontal direction and may place a restriction on the coding unit. When the current coding unit has a non-square shape, a height of which is larger than a width, the image decoding apparatus 100 may determine the coding unit at the predetermined location in a vertical direction.That is, the image decoding apparatus 100 may determine one of the coding units at different locations in a vertical direction and may place a restriction on the coding unit. According to one embodiment, the image decoding apparatus 100 may use information indicating respective locations of an even number of coding units, to determine the coding unit at the predetermined location among the even number of coding units. The image decoding apparatus 100 may use information indicating respective locations of an even number of coding units, to determine the coding unit at the predetermined location among the even number of coding units. IVIA / a / ZUzí J / UII ooo images 100 may determine an even number of coding units by dividing the current coding unit, and may determine the coding unit at the predetermined location by using information about the locations of the even number of coding units. An operation related thereto may correspond to the operation of determining a coding unit at a predetermined location (e.g., a center location) from among an odd number of coding units, which have been described in detail above in connection with FIG. 6, and thus detailed descriptions thereof are not provided herein. According to one embodiment, when a current non-square coding unit is divided into a plurality of coding units, predetermined information about a coding unit at a predetermined location may be used in a division operation to determine the coding unit at the predetermined location from among the plurality of coding units. For example, the image decoding apparatus 100 may use at least one of block shape information and information about a division shape mode, which is stored in a sample included in a coding unit at a central location, in a division operation to determine the coding unit at the central location from among the plurality of coding units determined by dividing the current coding unit. Referring to FIG. 6, the image decoding apparatus 100 may divide the current coding unit 600 into the plurality of coding units 620a, 620b, and 620c based on at least one of the block shape information and the information about the splitting shape mode, and may determine the coding unit 620b at a central location among the plurality of coding units 620a, 620b, and 620c. Additionally, the image decoding apparatus 100 may determine the coding unit 620b at the central location, in view of a location from which at least one of the block shape information and the information about the division shape mode is obtained. That is, at least one of the block shape information and the information about the division shape mode of the current coding unit 600 may be obtained from the sample 640 at a central location of the current coding unit 600, and when the current coding unit 600 is divided into the plurality of coding units 620a, 620b, and 620c based on at least one of the block shape information and the information about the division shape mode, the sample 640 may be obtained from the sample 640. IVIA / a / ZUzí J / UII ooo information about the split shape mode, the coding unit 620b including the sample 640 may be determined as the coding unit at the center location. However, the information used to determine the coding unit at the center location is not limited to at least one of block shape information and information about the split shape mode, and various kinds of information may be used to determine the coding unit at the center location. According to one embodiment, the predetermined information for identifying the coding unit at the predetermined location may be obtained from a predetermined sample that is included in a coding unit that is determined. With reference to FIG. 6, the image decoding apparatus 100 may use at least one of block shape information and information about the split shape mode, which is obtained from a sample at a predetermined location in the current coding unit 600 (for example, a sample at a center location of the current coding unit 600) to determine a coding unit at a predetermined location from among the plurality of coding units 620a, 620b and 620c determined by splitting the current coding unit 600 (for example, a coding unit at a center location from among a plurality of split coding units).That is, the image decoding apparatus 100 may determine the sample at the predetermined location by considering a block shape of the current coding unit 600, determine the coding unit 620b including a sample, from which predetermined information (for example, at least one of the block shape information and the information about the splitting shape mode) may be obtained, from among the plurality of coding units 620a, 620b, and 620c determined by splitting the current coding unit 600, and may place a predetermined constraint on the coding unit 620b.Referring to FIG. 6, according to one embodiment, the image decoding apparatus 100 may determine the sample 640 at the center location of the current coding unit 600 as the sample from which the predetermined information can be obtained, and may place a predetermined constraint on the coding unit 620b including the sample 640, in a decoding operation. However, the location of the sample from which the predetermined information can be obtained is not limited to the location described above, and may include arbitrary locations of samples included in the coding unit 620b that are determined for a constraint. According to one embodiment, the location of the sample from which the predetermined information can be obtained can be determined based on the shape of the current coding unit 600. According to one embodiment, the block shape information may indicate whether the current coding unit has a square or non-square shape, and the location of the sample from which the predetermined information can be obtained can be determined based on the shape. For example, the image decoding apparatus 100 may determine a sample located on a boundary for halving at least one of the width and the height of the current coding unit as the sample from which the predetermined information can be obtained, by using at least one of information about the width of the current coding unit and information about the height of the current coding unit.As another example, when the block shape information of the current coding unit indicates a non-square shape, the image decoding apparatus 100 may determine one of samples adjacent to a boundary for halving a long side of the current coding unit, as the sample from which the information can be obtained. IVIA / a / ZUzíó / UII ooo default. According to one embodiment, when the current coding unit is divided into a plurality of coding units, the image decoding apparatus 100 may use at least one of the block shape information and the information about the division shape mode to determine a coding unit at a predetermined location among the plurality of coding units.According to one embodiment, the image decoding apparatus 100 may obtain at least one of block shape information and information about the split shape mode from a sample at a predetermined location in a coding unit, and may divide the plurality of coding units generated by dividing the current coding unit by using at least one of the block shape information and information about the split shape mode obtained from the sample at the predetermined location in each of the plurality of coding units. That is, a coding unit may be repeatedly divided based on at least one of the block shape information and information about the split shape mode obtained from the sample at the predetermined location in each coding unit.An operation for repeatedly dividing a coding unit has been described iviA / a / zuzo / uii ooo above in connection with FIGURE 5, and thus detailed descriptions thereof will not be provided at this point. According to one embodiment, the image decoding apparatus 100 may determine one or more coding units by dividing the current coding unit, and may determine a decoding order of one or more of the coding units, based on a predetermined block (e.g., the current coding unit). FIGURE 7 illustrates a processing order of a plurality of coding units when the image decoding apparatus 100 determines the plurality of coding units by dividing a current coding unit, according to an embodiment. According to one embodiment, the image decoding apparatus 100 may determine second coding units 710a and 710b by dividing a first coding unit 700 in a vertical direction, determine second coding units 730a and 730b by dividing the first coding unit 700 in a horizontal direction, or determine second coding units 750a to 750d by dividing the first coding unit 700 in vertical and horizontal directions, based on the block shape information and the block shape information. IVIA / a / ZUzí J / UII ooo about a mode of division form. Referring to FIG. 7, the image decoding apparatus 100 may determine to process the second coding units 710a and 710b, which are determined by dividing the first coding unit 700 in a vertical direction, in a horizontal direction order 710c. The image decoding apparatus 100 may determine to process the second coding units 730a and 730b, which are determined by dividing the first coding unit 1400 in a horizontal direction, in a vertical direction order 730c.The image decoding apparatus 100 may determine to process the second coding units 750a to 750d, which are determined by dividing the first coding unit 700 in vertical and horizontal directions, in a predetermined order to process coding units in one row and then process coding units in a next row (for example, in a raster scan order or Z-scan order 750e). According to one embodiment, the image decoding apparatus 100 may repeatedly divide coding units. With reference to FIG. 7, the image decoding apparatus 100 may determine the plurality of coding units 710a, 710b, 730a, 730b, 730c, 730d, 730e, 730e, 730f, 730g, 730g, 730g, 730g, 730h, 730i ... 730b, 750a, 750b, 750c, and 750d by dividing the first coding unit 700, and may repeatedly divide each of the determined plurality of coding units 710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d. A method of dividing the plurality of coding units 710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d may correspond to a method of dividing the first coding unit 700. As such, each of the plurality of coding units 710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d may be independently divided into a plurality of coding units. 7 , the image decoding apparatus 100 may determine the second coding units 710a and 710b by dividing the first coding unit 700 in a vertical direction, and may determine whether or not to independently divide each of the second coding units 710a and 710b. According to an embodiment, the image decoding apparatus 100 may determine third coding units 720a and 720b by dividing the second left coding unit 710a in a horizontal direction and may not divide the second right coding unit 710b. According to one embodiment, a processing order of coding units may be determined based on an operation for dividing a coding unit. In other words, a processing order of divided coding units may be determined based on a processing order of coding units immediately before being divided. The image decoding apparatus 100 may determine a processing order of the third coding units 720a and 720b determined by dividing the second left coding unit 710a, independently of the second right coding unit 710b. Because the third coding units 720a and 720b are determined by dividing the second left coding unit 710a in a horizontal direction, the third coding units 720a and 720b may be processed in a vertical direction order 720c.Because the second left and right coding units 710a and 710b are processed in the horizontal direction order 710c, the second right coding unit 710b can be processed after the third coding units 720a and 720b included in the second left coding unit 710a are processed in the vertical direction order 720c. An operation for determining a processing order of coding units based on a coding unit before being divided is not limited to the example described above, and various methods. IVIA / a / ZUzí J / UII ooo can be used to independently process coding units, which are divided and determined for various forms, in a predetermined order. FIGURE 8 illustrates a process, performed by the image decoding apparatus 100, for determining that a current coding unit should be divided into an odd number of coding units, when the coding units are not processable in a predetermined order, according to an embodiment. According to one embodiment, the image decoding apparatus 100 may determine whether the current coding unit is divided into an odd number of coding units, based on obtained block shape information and information about a division shape mode. With reference to FIG. 8, a first square coding unit 800 may be divided into second non-square coding units 810a and 810b, and the second coding units 810a and 810b may be independently divided into third coding units 820a and 820b, and 820c to 820e. According to one embodiment, the image decoding apparatus 100 may determine the plurality of third coding units 820a and 820b by dividing the left second coding unit 810a in a horizontal direction, and may divide the right second coding unit 810b iviA / a / zuzo / uii ooo into an odd number of third coding units 820c to 82Oe.According to one embodiment, the image decoding apparatus 100 may determine whether any coding unit is divided into an odd number of coding units by determining whether the third coding units 820a and 820b, and 820c to 820e are processable in a predetermined order. Referring to FIG. 8, the image decoding apparatus 100 may determine the third coding units 820a and 820b, and 820c to 820e by repeatedly dividing the first coding unit 800. The image decoding apparatus 100 may determine whether any one of the first coding unit 800, the second coding units 810a and 810b, and the third coding units 820a and 820b, and 820c, 820d, and 820e are divided into an odd number of coding units, based on at least one of the block shape information and the information about the division shape mode.For example, the second right coding unit 810b may be divided into an odd number of third coding units 820c, 820d and 820e. 820e. A processing order of a plurality of coding units included in the first coding unit 800 may be a predetermined order (for example, a Z-scan order 830), and the image decoding apparatus 100 may decide whether the third coding units 820c, 820d, and 820e, which are determined by dividing the second right coding unit 810b into an odd number of coding units, satisfy a condition for processing in the predetermined order. According to one embodiment, the image decoding apparatus 100 may determine whether the third coding units 820a and 820b, and 820c, 820d, and 820e included in the first coding unit 800 satisfy the condition for processing in the predetermined order, and the condition refers to whether at least one of a width and a height of the second coding units 810a and 810b is divided in half along a boundary of the third coding units 820a and 820b, and 820c, 820d, and 820e. For example, the third coding units 820a and 820b determined by dividing in half the height of the second left non-square coding unit 810a satisfy the condition.However, because the boundaries of the third coding units 820c, 820d, and 820e determined by dividing the second right coding unit 810b into three coding units do not halve the width or height of the second right coding unit 810b, it can be determined that the third coding units 820c,. IVIA / a / ZUzí J / UII ooo 820d and 820e do not satisfy the condition. When the condition as described above is not satisfied, the image decoding apparatus 100 may decide to disconnect a scanning order, and may determine that the second right coding unit 810b is divided into an odd number of coding units, based on a result of the decision. According to one embodiment, when a coding unit is divided into an odd number of coding units, the image decoding apparatus 100 may place a predetermined restriction on a coding unit at a predetermined location among the divided coding units, and the restriction or the predetermined location have been described above in relation to various embodiments and thus detailed descriptions thereof will not be provided at this point. FIGURE 9 illustrates a process, performed by the image decoding apparatus 100, for determining at least one coding unit by dividing a first coding unit 900, according to an embodiment. According to one embodiment, the image decoding apparatus 100 may divide the first coding unit 900 based on at least one of block shape information and information about a division shape mode obtained by the bit stream obtainer 110. The first square coding unit 900 may be divided into four square coding units, or may be divided into a plurality of non-square coding units. For example, referring to FIG. 9 , when the block shape information indicates that the first coding unit 900 has a square shape and the information about the division shape mode indicates dividing the first coding unit 900 into non-square coding units, the image decoding apparatus 100 may divide the first coding unit 900 into a plurality of non-square coding units.In detail, when the information about the division shape mode indicates determining an odd number of coding units by dividing the first coding unit 900 in a horizontal direction or a vertical direction, the image decoding apparatus 100 may divide the first square coding unit 900 into an odd number of coding units, for example, second coding units 910a, 910b, and 910c determined by dividing the first square coding unit 900 in a vertical direction, or second coding units 920a, 920b, and 920c determined by dividing the first square coding unit 900 in a horizontal direction. According to one embodiment, the image decoding apparatus 100 may determine whether the second coding units 910a, 910b, 910c, 920a, 920b and 920c included in the first coding unit 900 satisfy a condition for processing in a predetermined order, and the condition relates to whether at least one of a width and a height of the first coding unit 900 is halved along a boundary of the second coding units 910a, 910b, 910c, 920a, 920b, and 920c. Referring to FIG. 9, because the boundaries of the second coding units 910a, 910b, and 910c determined by dividing the first square coding unit 900 in a vertical direction do not halve the width of the first coding unit 900, it can be determined that the first coding unit 900 does not satisfy the condition for processing in the predetermined order.Furthermore, because the boundaries of the second coding units 920a, 920b, and 920c determined by dividing the first square coding unit 900 in a horizontal direction do not halve the width of the first coding unit 900, it can be determined that the first coding unit 900 does not satisfy the condition for processing in the predetermined order. When the condition as described above is not satisfied, the image decoding apparatus 100 may decide to disconnect a scanning order, and may determine that the first coding unit 900 is divided into an odd order of coding units, based on a result of the decision. According to an embodiment, when a coding unit is divided into an odd number of coding units, the image decoding apparatus 100 may place a predetermined restriction on a coding unit at a predetermined location among the divided coding units, and the restriction or the predetermined location have been described above in relation to various embodiments and thus detailed descriptions thereof will not be provided at this point. According to one embodiment, the image decoding apparatus 100 may determine coding units in various ways by dividing a first coding unit. Referring to FIGURE 9, the image decoding apparatus 100 may divide the first square coding unit 900 or a first non-square coding unit 930 or 950 into coding units of various shapes. FIGURE 10 illustrates that a manner in which a second coding unit is divisible by the image decoding apparatus 100 is restricted when the second coding unit having a non-square shape, which is determined by dividing a first coding unit 1000, satisfies a predetermined condition, according to an embodiment. According to an embodiment, the image decoding apparatus 100 may determine to divide the first square coding unit 1000 into second non-square coding units 1010a, 1010b, 1020a, and 1020b, based on at least one of block shape information and information about a division shape mode, which is obtained by the bit stream obtainer 110. The second coding units 1010a, 1010b, 1020a, and 1020b may be divided independently. As such, the image decoding apparatus 100 may determine whether or not to divide the first coding unit 1000 into a plurality of coding units, based on at least one of the block shape information and the information about the splitting shape mode of each of the second coding units 1010a, 1010b, 1020a and 1020b.According to one embodiment, the image decoding apparatus 100 may determine the third coding units 1012a and 1012b by dividing the second left non-square coding unit 1010a, which is determined by dividing the first coding unit 1000 in a vertical direction, into a horizontal direction. However, when the second left coding unit 1010a is divided in a horizontal direction, the image decoding apparatus 100 may restrict the second right coding unit 1010b from being divided in a horizontal direction in which the second left coding unit 1010a is divided.When the third coding units 1014a and 1014b are determined by dividing the right second coding unit 1010b in the same direction, because the left and right second coding units 1010a and 1010b are divided independently in a horizontal direction, the third coding units 1012a, 1012b, 1014a and 1014b can be determined. However, this case also serves as a case in which the image decoding apparatus 100 divides the first coding unit 1000 into four square second coding units 1030a, 1030b, 1030c and 1030d, based on at least one of the block shape information and the information about the division shape mode, and may not be efficient in terms of image decoding. According to one embodiment, the image decoding apparatus 100 may determine third coding units 1022a, 1022b, 1024a and 1024b at the IVIA / a / ZUzíó / UII ooo dividing the second non-square coding unit 1020a or 1020b, which is determined by dividing the first coding unit 1000 in a horizontal direction, in a vertical direction. However, when a second coding unit (for example, the second upper coding unit 1020a) is divided in a vertical direction, for the reason described above, the image decoding apparatus 100 may restrict the other second coding unit (for example, the second lower coding unit 1020b) from being divided in a vertical direction in which the second upper coding unit 1020a is divided. FIGURE 11 illustrates a process, performed by the image decoding apparatus 100, for dividing a square coding unit when information about a division shape mode indicates that the square coding unit should not be divided into four square coding units, according to an embodiment. According to an embodiment, the image decoding apparatus 100 may determine second coding units 1110a, 1110b, 1120a, 1120b, etc. when dividing a first coding unit 1100, based on at least one of block shape information and information about a division shape mode. iviA / a / zuzo / uii ooo The information about the splitting shape mode may include information about various methods for splitting a coding unit, but the information about various splitting methods may not include information for splitting a coding unit into four square coding units. According to this information about a splitting shape mode, the image decoding apparatus 100 may not split the first square coding unit 1100 into four second square coding units 1130a, 1130b, 1130c, and 1130d. The image decoding apparatus 100 may determine the second non-square coding units 1110a, 1110b, 1120a, 1120b, etc., based on the information about the division shape mode. According to one embodiment, the image decoding apparatus 100 may independently divide the second non-square coding units 1110a, 1110b, 1120a, 1120b, etc. Each of the second coding units 1110a, 1110b, 1120a, 1120b, etc. may be repeatedly divided in a predetermined order, and this dividing method may correspond to a method for dividing the first coding unit 1100, based on at least one of the block shape information and the information about the division shape mode. For example, the image decoding apparatus 100 may determine third square coding units 1112a and 1112b by dividing the second left coding unit 1110a in a horizontal direction, and may determine third square coding units 1114a and 1114b by dividing the second right coding unit 1110b in a horizontal direction. Additionally, the image decoding apparatus 100 may determine third square coding units 1116a, 1116b, 1116c, and 1116d by dividing both the second left and right coding units 1110a and 1110b in a horizontal direction. In this case, coding units can be determined that have the same shape as the four second square coding units 1130a, 1130b, 1130c and 1130d divided from the first coding unit 1100. As another example, the image decoding apparatus 100 may determine third square coding units 1122a and 1122b by dividing the second upper coding unit 1120a in a vertical direction, and may determine third square coding units 1124a and 1124b by dividing the second lower coding unit 1120b in a vertical direction. Additionally, the image decoding apparatus 100 may determine third square coding units 1122a and 1122b by dividing the second upper coding unit 1120a in a vertical direction, and may determine third square coding units 1124a and 1124b by dividing the second lower coding unit 1120b in a vertical direction. IVIA / a / ZUzí J / UII ooo images 100 can determine third square coding units 1126a, 1126b, 1126c and 1126d by dividing both the upper and lower second coding units 1120a and 1120b in a vertical direction. In this case, coding units can be determined that have the same shape as the four second square coding units 1130a, 1130b, 1130c and 1130d divided from the first coding unit 1100. FIGURE 12 illustrates that a processing order among a plurality of coding units may be changed depending on the division process of a coding unit, according to an embodiment. According to one embodiment, the image decoding apparatus 100 may divide a first coding unit 1200 based on block shape information and information about a division shape mode. When the block shape information indicates a square shape and the division shape mode information indicates dividing the first coding unit 1200 in at least one of the horizontal and vertical directions, the image decoding apparatus 100 may determine second coding units 1210a, 1210b, 1220a, and 1220b when dividing the first coding unit 1200. Referring to FIG. 12, the non-square second coding units 1210a, 1210b, 1220a, and 1220b are IVIA / a / ZUzí J / UII ooo determined by dividing the first coding unit 1200 in only a horizontal direction or vertical direction may be divided independently based on the block shape information and the information about the division shape mode of each coding unit. For example, the image decoding apparatus 100 may determine third coding units 1216a, 1216b, 1216c, and 1216d by dividing the second coding units 1210a and 1210b, which are generated by dividing the first coding unit 1200 in a vertical direction, in a horizontal direction, and may determine third coding units 1226a, 1226b, 1226c, and 1226d. 1226d by dividing the second coding units 1220a and 1220b, which are generated by dividing the first coding unit 1200 in a horizontal direction, in a horizontal direction. A division operation of the second coding units 1210a, 1210b, 1220a and 1220b has been described above in connection with FIGURE 11, and thus detailed descriptions thereof will not be provided at this point. According to one embodiment, the image decoding apparatus 100 may process coding units in a predetermined order. An operation of processing coding units in a predetermined order has been described above in connection with FIG. 7 , and thus detailed descriptions thereof will not be provided here. 12 , the image decoding apparatus 100 may determine four third square coding units 1216a, 1216b, 1216c, 1216d, and 1226a, 1226b, 1226c, and 1226d by dividing the first square coding unit 1200. According to one embodiment, the image decoding apparatus 100 may determine processing orders of the third coding units 1216a, 1216b, 1216c, 1216d, and 1226a, 1226b, 1226c, and 1226d based on a method of dividing the first coding unit 1200. According to one embodiment, the image decoding apparatus 100 may determine the third coding units 1216a, 1216b, 1216c, and 1216d by dividing the second coding units 1210a and 1210b generated by dividing the first coding unit 1200 in a vertical direction, in a horizontal direction, and may process the third coding units 1216a, 1216b, 1216c, and 1216d in a processing order 1217 to initially process the third coding units 1216a and 1216c, which are included in the second left coding unit 1210a, in a vertical direction and then process the third coding units 1216b and 1216d, which are included in the second right coding unit 1210a. 1210b, in a vertical direction. According to an embodiment, the image decoding apparatus 100 may determine the third coding units 1226a, 1226b, 1226c, and 1226d by dividing the second coding units 1220a and 1220b generated by dividing the first coding unit 1200 in a horizontal direction, in a vertical direction, and may process the third coding units 1226a, 1226b, 1226c, and 1226d in a processing order 1227 to initially process the third coding units 1226a and 1226b, which are included in the second upper coding unit 1220a, in a horizontal direction and then process the third coding units 1226c and 1226d, which are included in the second lower coding unit 1220b, in a horizontal direction. Referring to FIGURE 12, the third square coding units 1216a, 1216b, 1216c and 1216d, and 1226a, 1226b, 1226c and 1226d can be determined by dividing the second coding units 1210a, 1210b, 1220a and 1220b, respectively. Although the second coding units 1210a and 1210b are determined by dividing the first coding unit 1200 in a vertical direction differently from the second coding units 1220a and 1220b which are determined by dividing the first coding unit 1200 in a horizontal direction, the third coding units 1216a, 1216b, 1216c and 1216d, and 1226a, 1226b, 1226c and 1226d divided therefrom eventually show coding units with the same shape divided from the first coding unit 1200.As such, by repeatedly dividing a coding unit in different ways based on at least one of the block shape information and the information about the division shape mode, the image decoding apparatus 100 can process a plurality of coding units in different orders even when it is eventually determined that the coding units are of the same shape. FIGURE 13 illustrates a process for determining a depth of a coding unit as a shape and size of the coding unit change, when the coding unit is repeatedly divided such that a plurality of coding units are determined, according to an embodiment. According to one embodiment, the image decoding apparatus 100 may determine the depth of the coding unit based on a predetermined criterion. For example, the predetermined criterion may be the length of a long side of the coding unit. When the length of a long side of a coding unit before being divided is 2n times (n>0) the length of a long side of a currently divided coding unit, the image decoding apparatus 100 may determine that a depth of the current coding unit is increased by n from a depth of the coding unit before being divided. In the following description, a coding unit having an increased depth is expressed as a coding unit of a greater depth. 13 , according to one embodiment, the image decoding apparatus 100 may determine a second coding unit 1302 and a third coding unit 1304 of greater depths by dividing a first square coding unit 1300 based on block shape information indicating a square shape (for example, the block shape information may be expressed as 0: SQUARE). Assuming that the size of the first square coding unit 1300 is 2Nx2N, the second coding unit 1302 determined by dividing a width and a height of the first coding unit 1300 by 1 / 2 may have a size of NxN. Additionally, the third coding unit 1304 determined by dividing a width and a height of the second coding unit 1302 by 1 / 2 may have a size of N / 2xN / 2. In this case, a width and a height of the first coding unit 1300 are divided into 1 / 2. IVIA / a / ZUzí J / UII ooo height of the third coding unit 1304 is 1 / 4 times that of the first coding unit 1300. When a depth of the first coding unit 1300 is D, a depth of the second coding unit 1302, the width and the height of which are 1 / 2 times those of the first coding unit 1300, may be D+l, and a depth of the third coding unit 1304, the width and the height of which are 1 / 4 times that of the first coding unit 1300, may be D+2. According to one embodiment, the image decoding apparatus 100 may determine a second coding unit 1312 or 1322 and a third coding unit 1314 or 1324 of greater depths by dividing a first non-square coding unit 1310 or 1320 based on block shape information indicating a non-square shape (for example, the block shape information may be expressed as 1: NS_VER indicating a non-square shape, a height of which is longer than a width, or as 2: NS HOR indicating a non-square shape, a width of which is longer than a height). The image decoding apparatus 100 may determine the second coding unit 1302, 1312, or 1322 by dividing at least one of a width and a height of the first coding unit 1310 having a size of Nx2N. That is, the image decoding apparatus 100 may determine the second coding unit 1302 having a size of NxN or the second coding unit 1322 having a size of NxN / 2 by dividing the first coding unit 1310 in a horizontal direction, or may determine the second coding unit 1312 having a size of N / 2xN by dividing the first coding unit 1310 in horizontal and vertical directions. According to one embodiment, the image decoding apparatus 100 may determine the second coding unit 1302, 1312, or 1322 by dividing at least one of a width and a height of the first coding unit 1320 having a size of 2NxN. That is, the image decoding apparatus 100 may determine the second coding unit 1302 having a size of NxN or the second coding unit 1312 having a size of N / 2xN by dividing the first coding unit 1320 in a vertical direction, or may determine the second coding unit 1322 having a size of NxN / 2 by dividing the first coding unit 1320 in horizontal and vertical directions. According to one embodiment, the image decoding apparatus 100 may determine the third coding unit 1304, 1314, or 1324 by dividing at least one of a width and a height of the second coding unit 1302 having a size of NxN. That is, the image decoding apparatus 100 may determine the third coding unit 1304 having a size of N / 2xN / 2, the third coding unit 1314 having a size of N / 4xN / 2, or the third coding unit 1324 having a size of N / 2xN / 4 by dividing the second coding unit 1302 in vertical and horizontal directions. According to one embodiment, the image decoding apparatus 100 may determine the third coding unit 1304, 1314, or 1324 by dividing at least one of a width and a height of the second coding unit 1312 having a size of N / 2xN. That is, the image decoding apparatus 100 may determine the third coding unit 1304 having a size of N / 2xN / 2 or the third coding unit 1324 having a size of N / 2xN / 4 by dividing the second coding unit 1312 in a horizontal direction, or may determine the third coding unit 1314 having a size of N / 4xN / 2 by dividing the second coding unit 1312 in vertical and horizontal directions. According to one embodiment, the image decoding apparatus 100 may determine the third coding unit 1304, 1314, or 1324 by dividing at least one of a width and a height of the second coding unit 1322 having a size of NxN / 2. That is, the image decoding apparatus 100 may determine the third coding unit 1304 having a size of N / 2xN / 2 or the third coding unit 1314 having a size of N / 4xN / 2 by dividing the second coding unit 1322 in a vertical direction, or may determine the third coding unit 1324 having a size of N / 2xN / 4 by dividing the second coding unit 1322 in vertical and horizontal directions. According to one embodiment, the image decoding apparatus 100 may divide the square coding unit 1300, 1302, or 1304 in a horizontal or vertical direction. For example, the image decoding apparatus 100 may determine the first coding unit 1310 having a size of Nx2N by dividing the first coding unit 1300 having a size of 2Nx2N in a vertical direction, or may determine the first coding unit 1320 having a size of 2NxN by dividing the first coding unit 1300 in a horizontal direction. According to one embodiment, when a depth is determined based on the length of the longest side of a coding unit, a depth of a coding unit determined by dividing the first coding unit 1300 having a size of 2Nx2N in a horizontal or vertical direction may be the same as the depth of the first coding unit 1300. According to one embodiment, a width and a height of the third coding unit 1314 or 1324 may be 1 / 4 times that of the first coding unit 1310 or 1320. When a depth of the first coding unit 1310 or 1320 is D, a depth of the second coding unit 1312 or 1322, the width and height of which are 1 / 2 times those of the first coding unit 1310 or 1320, may be D+1, and a depth of the third coding unit 1314 or 1324, the width and height of which are 1 / 4 times those of the first coding unit 1310 or 1320, may be D+2. FIGURE 14 illustrates depths that are determinable based on shapes and sizes of coding units, and partial indices (PIDs) that are to distinguish coding units, according to a modality. According to one embodiment, the image decoding apparatus 100 may determine second coding units in a plurality of ways when dividing a square first coding unit 1400. With reference to FIG. 14 , the image decoding apparatus 100 may determine second coding units 1402a and 1402b, 1404a and 1404b, and 1406a, 1406b, 1406c and 1406d when dividing the first coding unit 1400 in at least one of the vertical and horizontal directions based on information about a division shape mode. That is, the image decoding apparatus 100 may determine the second coding units 1402a and 1402b, 1404a and 1404b, and 1406a, 1406b, 1406c and 1406d, based on the information about the splitting shape mode of the first coding unit 1400. According to an embodiment, a depth of the second coding units 1402a and 1402b, 1404a and 1404b, and 1406a, 1406b, 1406c and 1406d, which are determined based on information about the division shape mode of the first square coding unit 1400, may be determined based on the length of a long side thereof. For example, because the length of a side of the first square coding unit 1400 is equal to the length of a long side of the second non-square coding units 1402a and 1402b, and 1404a and 1404b, the first coding unit 1400 and the second non-square coding units 1402a and 1402b, and 1404a and 1404b may have the same depth, for example, D. However, when the apparatus IVIA / a / ZUzíó / UII ooo image decoding 100 divides the first coding unit 1400 into the four second square coding units 1406a, 1406b, 1406c and 1406d based on the information about the division shape mode, because the length of a side of the second square coding units 1406a, 1406b, 1406c and 1406d is 1 / 2 times a length of a side of the first coding unit 1400, a depth of the second coding units 1406a, 1406b, 1406c and 1406d may be D+l, which is deeper than the depth D of the first coding unit 1400 by 1. According to one embodiment, the image decoding apparatus 100 may determine a plurality of second coding units 1412a and 1412b, and 1414a, 1414b, and 1414c when dividing a first coding unit 1410, a height of which is longer than a width, in a horizontal direction based on information about the dividing shape mode. According to one embodiment, the image decoding apparatus 100 may determine a plurality of second coding units 1422a and 1422b, and 1424a, 1424b, and 1424c when dividing a first coding unit 1420, a width of which is longer than a height, in a vertical direction based on information about the shape mode. IVIA / a / ZUzí J / UII ooo of division. According to an embodiment, a depth of the second coding units 1412a and 1412b, 1414a, 1414b and 1414c, 1422a and 1422b, and 1424a, 1424b and 1424c, which are determined based on information about the splitting shape mode of the first non-square coding unit 1410 or 1420, may be determined based on the length of a long side thereof. For example, because the length of a side of the second square coding units 1412a and 1412b is 1 / 2 times the length of a long side of the first coding unit 1410 having a non-square shape, a height of which is longer than a width, a depth of the second square coding units 1412a and 1412b is D+1, which is deeper than the depth D of the first non-square coding unit 1410 by 1. Additionally, the image decoding apparatus 100 may divide the first non-square coding unit 1410 into an odd number of second coding units 1414a, 1414b, and 1414c based on the information about the division shape mode. The odd number of second coding units 1414a, 1414b, and 1414c may include the second non-square coding units 1414a and 1414c and the second square coding unit iviA / a / zuzo / uii ooo 1414b. In this case, because the length of a long side of the second non-square coding units 1414a and 1414c and the length of a side of the second square coding unit 1414b are 1 / 2 times the length of a long side of the first coding unit 1410, a depth of the second coding units 1414a, 1414b and 1414c may be D+1, which is deeper than the depth D of the first non-square coding unit 1410 by 1. The image decoding apparatus 100 may determine depths of divided coding units of the first coding unit 1420 having a non-square shape, a width of which is longer than a height, by using the above-described method for determining depths of divided coding units of the first coding unit 1410. According to one embodiment, the image decoding apparatus 100 may determine PIDs for identifying divided coding units based on a size relationship between the coding units when an odd number of divided coding units do not have equal sizes. Referring to FIG. 14 , a coding unit 1414b at a central location among an odd number of divided coding units 1414a, 1414b, and 1414c may have a width equal to that of the other coding units 1414a and 1414c and a height of 0.10 which is twice that of the other coding units 1414a and 1414c. That is, in this case, the coding unit 1414b at the central location may include two of the other coding unit 1414a or 1414c.Therefore, when a PID of the coding unit 1414b at the center location is 1 based on a scanning order, a PID of the coding unit 1414c located after the coding unit 1414b may be incremented by 2 and thus may be 3. That is, discontinuity in the PID values ​​may be present. According to one embodiment, the image decoding apparatus 100 may determine whether an odd number of divided coding units do not have equal sizes, based on whether discontinuity is present in PIDs to identify the divided coding units. According to one embodiment, the image decoding apparatus 100 may determine whether to use a specific division method, based on PID values, to identify a plurality of determined coding units when dividing a current coding unit. With reference to FIG. 14, the image decoding apparatus 100 may determine an odd number of coding units 1412a and 1412b or an odd number of coding units 1414a, 1414b, and 1414c when dividing the first coding unit. IVIA / a / ZUzí J / UII ooo coding unit 1410 having a rectangular shape, a height of which is longer than a width. The image decoding apparatus 100 may use PIDs to identify respective coding units. According to one embodiment, the PID may be obtained from a sample of a predetermined location of each coding unit (e.g., an upper left sample). According to one embodiment, the image decoding apparatus 100 may determine a coding unit at a predetermined location among the divided coding units by using the PIDs to distinguish the coding units. According to one embodiment, when information about the division shape mode of the first coding unit 1410 having a rectangular shape, a height of which is longer than a width, indicates dividing a coding unit into three coding units, the image decoding apparatus 100 may divide the first coding unit 1410 into three coding units 1414a, 1414b, and 1414c. The image decoding apparatus 100 may assign a PID to each of the three coding units 1414a, 1414b, and 1414c. 1414c. The image decoding apparatus 100 may compare PIDs of an odd number of divided coding units to determine a coding unit at a central location among the coding units. The image decoding apparatus 100 may determine the coding unit 1414b having a PID corresponding to an intermediate value among the PIDs of the coding units as the coding unit at the central location among the coding units determined by dividing the first coding unit 1410. According to one embodiment, the image decoding apparatus 100 may determine PIDs for distinguishing divided coding units based on a size relationship between the coding units when the divided coding units are not of equal size.Referring to FIG. 14, the coding unit 1414b generated by dividing the first coding unit 1410 may have a width equal to that of the other coding units 1414a and 1414c and a height which is twice that of the other coding units 1414a and 1414c. In this case, when the PID of the coding unit 1414b at the center location is 1, the PID of the coding unit 1414c located after the coding unit 1414b may be increased by 2 and thus may be 3. When the PID is not increased uniformly as described above, the image decoding apparatus 100 may determine that a coding unit is divided into iviA / a / zuzo / uii or a plurality of coding units including a coding unit having a size different from that of the other coding units.According to one embodiment, when the information about the splitting shape mode indicates splitting a coding unit into an odd number of coding units, the image decoding apparatus 100 may split a current coding unit such that a coding unit at a predetermined location among an odd number of coding units (e.g., a coding unit at a center location) has a size different from that of the other coding units. In this case, the image decoding apparatus 100 may determine the coding unit at the center location having a different size by using PIDs of the coding units.However, the PIDs and the size or location of the coding unit of the default location are not limited to the examples described above, and multiple PIDs and multiple locations and sizes of coding units may be used. According to one embodiment, the image decoding apparatus 100 may use a predetermined data unit where an encoding unit begins to be divided repeatedly. iviA / a / zuzo / uii ooo FIGURE 15 illustrates that a plurality of coding units are determined based on a plurality of predetermined data units that are included in a visual representation, according to an embodiment. According to one embodiment, a predetermined data unit may be defined as a data unit wherein a coding unit begins to be repeatedly divided by using at least one of block shape information and information about a division shape mode. That is, the predetermined data unit may correspond to a coding unit of the highest depth, which is used to determine a plurality of divided coding units of a current visual representation. In the following descriptions, for convenience of explanation, the predetermined data unit is referred to as a reference data unit. According to one embodiment, the reference data unit may have a predetermined size and a predetermined size shape. According to one embodiment, the reference data unit may include MxN samples. In this document, M and N may be equal to each other, and may be integers expressed as powers of 2. That is, the reference data unit may have a square or non-square shape and may be divided into an integer of coding units. According to one embodiment, the image decoding apparatus 100 may divide the current visual representation into a plurality of reference data units. According to one embodiment, the image decoding apparatus 100 may divide the plurality of reference data units, which are divided from the current visual representation, by using information about a division shape mode for each reference data unit. The division operation of the reference data unit may correspond to a division operation using a quad tree structure. According to one embodiment, the image decoding apparatus 100 may predetermine the minimum allowable size for reference data units included in the current display. Accordingly, the image decoding apparatus 100 may determine a plurality of reference data units having sizes equal to or larger than the minimum size, and may determine one or more coding units by using the block shape information and the information about the partitioning shape mode with reference to the determined reference data unit. IVIA / a / ZUzí J / UII ooo Referring to FIGURE 15, the image decoding apparatus 100 may use a square reference coding unit 1500 or a non-square reference coding unit 1502. According to one embodiment, the size and shape of the reference coding units may be determined based on a plurality of data units capable of including one or more reference coding units (e.g., sequences, visual representations, slices, slice segments, larger coding units, or the like). According to one embodiment, the bit stream getter 110 of the image decoding apparatus 100 may obtain, from a bit stream, at least one of reference coding unit shape information and reference coding unit size information with respect to each of the plurality of data units. An operation of dividing the square reference coding unit 1500 into one or more coding units has been described above in connection with the current coding unit division operation 300 of FIG. 3 , and an operation of dividing the non-square reference coding unit 1502 into one or more coding units has been described above in connection with the current coding unit division operation 300 of FIG. IVIA / a / ZUzí J / UII ooo division of the current coding unit 400 or 450 of the FIGURE 4, and thus, detailed descriptions of them will not be provided at this point. According to one embodiment, the image decoding apparatus 100 may use a PID to identify the size and shape of reference coding units, to determine the size and shape of reference coding units according to some data units determined in advance based on a predetermined condition. That is, the bit stream obtainer 110 may obtain, from the bit stream, only the PID to identify the size and shape of reference coding units with respect to each slice, slice segment, or the largest coding unit which is a data unit satisfying a predetermined condition (e.g., a data unit having a size equal to or smaller than a slice) among the various data units (e.g., sequences, visual representations, slices, slice segments, the largest coding units, or the like).The image decoding apparatus 100 may determine the size and shape of reference data units with respect to each data unit which satisfies the predetermined condition by using the PID. When the reference coding unit shape information and the reference coding unit size information are obtained and used from the bit stream according to each data unit having a relatively small size, the efficiency of using the bit stream may not be high, and therefore, only the PID may be obtained and used instead of directly obtaining the reference coding unit shape information and the reference coding unit size information.In this case, at least one of the size and shape of reference coding units corresponding to the PID for identifying the size and shape of reference coding units may be predetermined. That is, the image decoding apparatus 100 may determine at least one of the size and shape of reference coding units included in a data unit serving as a unit for obtaining the PID, by selecting at least one of the predetermined size and shape of reference coding units based on the PID. According to one embodiment, the image decoding apparatus 100 may use one or more reference coding units included in the larger coding unit. That is, the divided larger coding unit of a visual representation may include one or more reference coding units, and the coding units may be determined by dividing IVIA / a / ZUzí J / UII ooo repeatedly each reference coding unit. According to one embodiment, at least one of a width and a height of the larger coding unit may be an integer number of times at least one of the width and height of the reference coding units. According to one embodiment, the size of the reference coding units may be obtained by dividing the larger coding unit n times based on a quad tree structure. That is, the image decoding apparatus 100 may determine the reference coding units by dividing the larger coding unit n times based on a quad tree structure, and may divide the reference coding unit based on at least one of the block shape information and the information about the division shape mode according to various embodiments. FIGURE 16 illustrates a processing block that serves as a unit for determining an order of determining reference coding units included in a visual representation 1600, according to one embodiment. According to one embodiment, the image decoding apparatus 100 may determine one or more partitioned processing blocks of a visual representation. The processing block is a data unit that includes one or more partitioned reference coding units of a visual representation, and one or more of the reference coding units included in the processing block may be determined according to a specific order. That is, an order of determining the one or more reference coding units determined in each processing block may correspond to one of several types of orders for determining reference coding units, and may vary depending on the processing block.The order of determining reference coding units, which is determined with respect to each processing block, may be one of several orders, for example, raster scan order, Z-scan order, N-scan order, diagonal up-scan order, horizontal scan order, and vertical scan order, but is not limited to the above-mentioned scanning orders. According to one embodiment, the image decoding apparatus 100 may obtain processing block size information and may determine the size of one or more processing blocks included in the visual representation. The image decoding apparatus 100 may obtain the processing block size information from a bit stream and may determine the size of one or more processing blocks included in the visual representation. The processing block size may be a predetermined data unit size, which is indicated by the processing block size information. According to one embodiment, the bit stream obtainer 110 of the image decoding apparatus 100 may obtain the processing block size information from the bit stream according to each specific data unit. For example, the processing block size information may be obtained from the bit stream in a data unit such as an image, sequence, visual representation, slice, or slice segment.That is, the bit stream obtainer 110 may obtain processing block size information of the bit stream according to each of the various data units, the image decoding apparatus 100 may determine the size of one or more processing blocks, which are divided from the visual representation, by using the obtained processing block size information, and the size of the processing blocks may be an integer number of times that of the coding units of. IVIA / a / ZUzíó / UII ooo reference. According to one embodiment, the image decoding apparatus 100 may determine the size of the processing blocks 1602 and 1612 included in the visual representation 1600. For example, the image decoding apparatus 100 may determine the size of processing blocks based on the processing block size information obtained from the bit stream. With reference to FIG. 16, according to one embodiment, the image decoding apparatus 100 may determine a width of the processing blocks 1602 and 1612 to be four times the width of the reference coding units, and may determine a height of the processing blocks 1602 and 1612 to be four times the height of the reference coding units. The image decoding apparatus 100 may determine an order of determining one or more reference coding units in the one or more processing blocks. According to one embodiment, the image decoding apparatus 100 may determine the processing blocks 1602 and 1612, which are included in the visual representation 1600, based on the size of processing blocks, and may determine an order of determining one or more reference coding units included in the processing blocks 1602 and 1612. IVIA / a / ZUzí J / UII ooo 1612. According to one embodiment, determining reference coding units may include determining the size of the reference coding units. According to one embodiment, the image decoding apparatus 100 may obtain, from the bit stream, determination order information of one or more reference coding units included in one or more processing blocks, and may determine a determination order with respect to the one or more reference coding units based on the obtained determination order information. The determination order information may be defined as an order or direction for determining the reference coding units in the processing block. That is, the determination order of reference coding units may be determined independently with respect to each processing block. According to one embodiment, the image decoding apparatus 100 may obtain, from the bit stream, reference coding unit determination order information according to each specific data unit. For example, the bit stream obtainer 110 may obtain reference coding unit determination order information iviA / a / zuzo / uii ooo. 100 of the bit stream according to each data unit such as an image, sequence, visual representation, slice, slice segment, or processing block. Because the reference coding unit determination order information indicates an order for determining reference coding units in a processing block, the determination order information can be obtained with respect to each specific data unit that includes an integer number of processing blocks. According to one embodiment, the image decoding apparatus 100 may determine one or more reference coding units based on the reference determination order. According to one embodiment, the bit stream obtainer 110 may obtain the determination order information of reference coding units from the bit stream as information related to the processing blocks 1602 and 1612, and the image decoding apparatus 100 may determine a determination order of one or more reference coding units included in the processing blocks 1602 and 1612 and may determine one or more reference coding units, which are included in the visual representation 1600, based on the determination order. With reference to FIG. 16, the image decoding apparatus 100 may obtain the determination order information of the reference coding units of the bit stream as information related to the processing blocks 1602 and 1612. 101 images 100 may determine determination orders 1604 and 1614 of one or more reference coding units in processing blocks 1602 and 1612, respectively. For example, when the reference coding unit determination order information is obtained with respect to each processing block, different kinds of the reference coding unit determination order information may be obtained for processing blocks 1602 and 1612. When the determination order 1604 of reference coding units in processing block 1602 is a frame scanning order, the reference coding units included in processing block 1602 may be determined according to a frame scanning order.On the contrary, when the determination order 1614 of reference coding units in the other processing block 1612 is a backward frame scanning order, the reference coding units included in the processing block 1612 may be determined according to the backward frame scanning order. According to one embodiment, the image decoding apparatus 100 may decode one or more of the determined reference coding units. The image decoding apparatus 100 may 102 decode an image, based on the reference coding units determined as described above. A method for decoding the reference coding units may include various image decoding methods. According to one embodiment, the image decoding apparatus 100 may obtain block shape information indicating a shape of a current coding unit or information about a split shape mode indicating a splitting method of the current coding unit, from the bit stream, and may use the obtained information. The block shape information or the information about the split shape mode may be included in the bit stream related to plural data units. For example, the image decoding apparatus 100 may use the block shape information or the information about the split shape mode included in a sequence parameter set, a display parameter set, a video parameter set, a slice header, or a slice segment header.Additionally, the image decoding apparatus 100 may obtain, from the bit stream, a syntax element corresponding to the block shape information or the information about. IVIA / a / ZUzí J / UII ooo of the division form mode according to each unit of 103 larger encoding, each reference coding unit or each processing block, and can use the obtained syntax element. FIGURE 17 illustrates coding units determinable by visual representation when a combination of forms into which a coding unit is divisible is different by visual representation, according to the modality. 17 , the image decoding apparatus 100 may differently determine, per visual representation, a combination of ways in which the coding unit is divisible. For example, the image decoding apparatus 100 may decode an image by using a visual representation that is divisible into 4 coding units, a visual representation 1710 that is divisible into 2 or 4 coding units, and a visual representation 1720 that is divisible into 2, 3, or 4 coding units, from among at least one visual representation included in the image. For the purpose of dividing the visual representation 1700 into a plurality of coding units, the image decoding apparatus 100 may use only division manner information indicating that the visual representation 1700 is divided into 4 coding units. 104 square coding. For the purpose of dividing the visual representation 1710, the image decoding apparatus 100 may use only division manner information indicating that the visual representation 1710 is divided into 2 or 4 coding units. For the purpose of dividing the visual representation 1720, the image decoding apparatus 100 may use only division manner information indicating that the visual representation 1720 is divided into 2, 3, or 4 coding units. Because this combination of division manners is only an embodiment for describing operations of the image decoding apparatus 100, it should not be construed that the combination of division manners is limited to the embodiment, and various combinations of division manners may be used according to predetermined data units. According to one embodiment, the bit stream obtainer 110 of the image decoding apparatus 100 may obtain a bit stream including an index indicating a combination of splitting shape information according to predetermined data units (e.g., sequences, visual representations, or slices). For example, the bit stream obtainer 110 may obtain an index indicating a combination of splitting shape information from a set of iviA / a / zuzo / uii ooo 105 sequence parameters, a set of display parameters, or a slice header. The image decoding apparatus 100 may determine a combination of splitting methods into which a coding unit is divisible according to the predetermined data units by using the obtained index, and thus different combinations of splitting methods may be used according to predetermined data units. FIGURE 18 illustrates various forms of a coding unit determinable based on division shape information representable as a binary code, according to one embodiment. According to an embodiment, the image decoding apparatus 100 may divide a coding unit into various forms by using block form information and division form information obtained by the bit stream acquirer 110. The forms into which a coding unit is divisible may correspond to various forms including the forms described through the above embodiments. Referring to FIG. 18, the image decoding apparatus 100 may divide a coding unit having a square shape in at least one direction from a horizontal direction and a horizontal direction. 106 vertical direction and can divide a coding unit having a non-square shape in a horizontal direction or a vertical direction, based on division shape information. According to one embodiment, when the image decoding apparatus 100 is capable of dividing a coding unit having a square shape in a horizontal direction and a vertical direction to obtain four square coding units, the number of division shapes that can be indicated by division shape information about the coding unit having the square shape may be 4. According to one embodiment, the division shape information may be represented as a 2-digit binary code, and a binary code may be assigned to each division shape.For example, when a coding unit is not divided, the division shape information can be represented as (00)b; when a coding unit is divided in a horizontal direction and a vertical direction, the division shape information can be represented as (01)b; when a coding unit is divided in a horizontal direction, the division shape information can be represented as (10)b; and when a coding unit is divided in a vertical direction, the division shape information can be represented as. 107 (11)b. According to one embodiment, when the image decoding apparatus 100 divides a coding unit having a non-square shape in a horizontal direction or a vertical direction, the types of division shapes that can be indicated by the division shape information can be determined according to the number of coding units into which a coding unit is divided. With reference to FIG. 18, the image decoding apparatus 100 may divide a coding unit having a non-square shape into 3 coding units according to one embodiment. The image decoding apparatus 100 may divide a coding unit into two coding units, and in this case, the division shape information can be represented as (10)b.The image decoding apparatus 100 may divide a coding unit into three coding units, and in this case, the division shape information may be represented as (11)b. The image decoding apparatus 100 may determine not to divide a coding unit, and in this case, the division shape information may be represented as (0)b. That is, for the purpose of using a binary code indicating division shape information, the decoding apparatus. QQQI 108 images 100 can use variable length coding (VLC), instead of fixed length coding (FLC). According to one embodiment, with reference to FIG. 18, a binary code of division shape information indicating that a coding unit is not divided may be represented as (0)b. When a binary code of division shape information indicating that a coding unit is not divided is set to (00)b, all 2-bit binary codes of division shape information have to be used even though there is no division shape information set to (01)b. However, as shown in FIG. 18, when 3 division shapes are used for a coding unit having a non-square shape, the image decoding apparatus 100 may determine not to divide a coding unit even by using a 1-bit binary code (0)b as the division shape information, thereby efficiently utilizing a bit stream.However, the division shapes of a coding unit having a non-square shape, which are indicated by the division shape information, should not be interpreted as being limited to the 3 shapes shown in FIGURE 18 and should be interpreted as being various shapes including the above embodiments. iviA / a / zuzo / uii ooo 109 FIGURE 19 illustrates other forms of a coding unit determinable based on division shape information representable as a binary code, according to one embodiment. Referring to FIG. 19, the image decoding apparatus 100 may divide a coding unit having a square shape in a horizontal direction or a vertical direction and may divide a coding unit having a non-square shape in a horizontal direction or a vertical direction, based on division shape information. That is, the division shape information may indicate that a coding unit having a square shape is divided in one direction. In this case, a binary code of division shape information indicating that a coding unit having a square shape is not divided may be represented as (0)b.When a division shape information binary code indicating that a coding unit is not divided is set to (00)b, all 2-bit division shape information binary codes have to be used even though there is no division shape information set to (01)b. However, as shown in FIG. 19, when 3 division shapes are used for a coding unit having a square shape, the image decoding apparatus. 110 100 may determine not to divide a coding unit even by using a 1-bit binary code (0)b as the division shape information, thereby efficiently utilizing a bit stream. However, the division shapes of a coding unit having a square shape, which are indicated by the division shape information, should not be construed as being limited to the 3 shapes shown in FIG. 19 and should be construed as being various shapes including the above embodiments. According to one embodiment, the block shape information or the slice shape information may be represented using a binary code, and this information may be immediately output as a bit stream. Alternatively, the block shape information or slice shape information representable as a binary code may not be immediately output in a bit stream and may be used as a binary code input during context-adaptive binary arithmetic coding (CABAC). According to one embodiment, a process will be described, performed by the image decoding apparatus 100, for obtaining syntax about block shape information or division shape information through iviA / a / zuzo / uii ooo 111 of CABAC. A bit stream including a binary code for the syntax may be obtained by the bit stream obtainer 110. The image decoding apparatus 100 may detect a syntax element indicating block shape information or division shape information by debinarizing a sequence of binary digits included in the obtained bit stream. According to one embodiment, the image decoding apparatus 100 may obtain a set of binary sequences of binary digits corresponding to the syntax element being decoded, and may decode each binary digit by using probability information, and the image decoding apparatus 100 may repeatedly perform this process until a sequence of binary digits including these decoded binary digits is the same as previously obtained sequences of binary digits.The image decoding apparatus 100 may determine the syntax element by debinarizing the sequence of binary digits. According to one embodiment, the image decoding apparatus 100 may determine a syntax about a sequence of binary digits by performing an adaptive binary arithmetic coding decoding process, and may update a probability model for binary digits obtained by the image stream obtainer. IVIA / a / ZUzí J / UII ooo 112 bits 110. Referring to FIG. 18, the bit stream obtainer 110 of the image decoding apparatus 100 may obtain a bit stream indicating a binary code indicating splitting shape information according to an embodiment. The image decoding apparatus 100 may determine a syntax about the splitting shape information by using the obtained binary code having a size of 1 bit or 2 bits. For the purpose of determining the syntax about the splitting shape information, the image decoding apparatus 100 may update a probability of each bit among the 2 bits of the binary code. That is, the image decoding apparatus 100 may update a probability that may have a value of 0 or 1 when decoding a next binary digit according to whether a value of a first binary digit in the 2 bits of the binary code is 0 or 1. According to one embodiment, while determining the syntax, the image decoding apparatus 100 may update a probability of the binary digits used in a process for decoding the binary digits of the binary digit sequence for the syntax, and the image decoding apparatus 100 may determine that a specific bit in the binary digit sequence has the same probability without updating iviA / a / zuzo / uii ooo 113 probability. Referring to FIG. 18, while determining the syntax by using a sequence of binary digits indicating division shape information about a coding unit having a non-square shape, the image decoding apparatus 100 may determine the syntax about the division shape information by using a binary digit having a value of 0 when the coding unit having a non-square shape is not divided. That is, when the block shape information indicates that a current coding unit has a non-square shape, a first binary digit of a sequence of binary digits for the division shape information may be 0 when the coding unit having a non-square shape is not divided, and may be 1 when the coding unit having a non-square shape is divided into two or three coding units.Accordingly, a probability that a first binary digit of a binary digit sequence of division shape information about a coding unit having a non-square shape is 0 may be 1 / 3, and a probability that the first binary digit of the binary digit sequence of division shape information about the coding unit having a non-square shape is 1 may be 2 / 3. As described. IVIA / a / ZUzí J / UII ooo 114 above, due to the division shape information indicating that a coding unit having a non-square shape cannot only represent a 1-bit binary digit sequence having a value of 0, the image decoding apparatus 100 can determine a syntax about the division shape information by determining whether a second binary digit is 0 or 1 only when the first binary digit of the division shape information is 1. According to one embodiment, when the first binary digit for the division shape information is 1, the image decoding apparatus 100 can decode a binary digit by determining that probabilities of the second binary digit being 0 and 1 are the same. According to one embodiment, the image decoding apparatus 100 may use various probabilities for each binary digit while determining a binary digit of a sequence of binary digits for division shape information. According to one embodiment, the image decoding apparatus 100 may differently determine probabilities of binary digits for division shape information according to an address of a non-square block. According to one embodiment, the image decoding apparatus 100 may differently determine iviA / a / zuzo / uii ooo 115 binary digit probabilities for division shape information according to an area or a length of a long side of a current coding unit. According to one embodiment, the image decoding apparatus 100 may differently determine binary digit probabilities for division shape information according to at least one of a shape and a length of a long side of a current coding unit. According to one embodiment, the image decoding apparatus 100 may determine that binary digit probabilities for division shape information are the same with respect to coding units having a predetermined size or larger. For example, the image decoding apparatus 100 may determine that binary digit probabilities for division shape information are the same with respect to coding units having a size equal to or larger than 64 samples based on a length of a long side of each coding unit. According to one embodiment, the image decoding apparatus 100 may determine an initial probability of binary digits constituting a sequence of binary digits of slice shape information based on a slice type (e.g., a iviA / a / zuzo / uii ooo). 116 I-cut, P-cut, B-cut, or similar). FIGURE 20 is a block diagram of an image encoding and decoding system 2000 for performing loop filtering. An encoding end 2010 of an image encoding and decoding system 2000 transmits an encoded bit stream of an image, and a decoding end 2050 receives and decodes the bit stream and outputs a reconstruction image. The encoding end 2010 may have a configuration similar to that of an image coding apparatus 200 which will be described later, and the decoding end 2050 may have a configuration similar to that of the image decoding apparatus 100. At the encoding end 2010, a prediction encoder 2015 outputs a reference image through inter-prediction and intra-prediction, and a transformer and quantizer 2020 quantizes residual data between the reference image and a current input image into a quantized transform coefficient and outputs the quantized transform coefficient. An entropy encoder 2025 encodes and transforms the quantized transform coefficient into a bit stream and outputs the bit stream. The quantized transform coefficient is reconstructed. 117 as data in a spatial domain by a dequantizer and inverse converter 2030, and the reconstructed data in the spatial domain is output as a reconstruction image through a deblocking filter 2035 and a loop filter 2040. The reconstruction image may be used as a reference image of a next input image through the prediction encoder 2015. The encoded image data from the bit stream received by the decoding end 2050 is reconstructed as residual data in a spatial domain via an entropy decoder 2055 and a dequantizer and inverse converter 2060. The image data in a spatial domain is formed as the residual data and a reference image output from a prediction decoder 2075 are combined, and a deblocking filter 2065 and a loop filter 2070 may filter the image data in the spatial domain and may output a reconstruction image for a current original image. The reconstruction image may be used as a reference image for a next original image by the prediction decoder 2075. The loop filter 2040 of the coding end 2010 performs loop filtering by using filter information entered according to a user input or a system setting. The information 118 filter used by the loop filter 2040 is sent to the entropy encoder 2025, and is transmitted together with the encoded image data to the decoding end 2050. The loop filter 2070 of the decoding end 2050 can perform loop filtering based on the filter information inputted from the decoding end 2050. FIGURE 21 illustrates an example of filter units included in the larger coding unit and filtering performance information of a filter unit, according to one embodiment. When the filtering units of the loop filter 2040 of the encoding end 2010 and the loop filter 2070 of the decoding end 2050 include data units similar to encoding units according to an embodiment described with reference to FIGS. 3 through 5, the filter information may include block shape information and division shape information of a data unit for indicating a filtering unit, and loop filtering performance information indicating whether loop filtering is performed in the filtering unit. The filtering units included in the larger coding unit 2100 according to one embodiment may have the same block shape and division shape as IVIA / a / ZUzí J / UII ooo coding units included in the unit of 119 largest coding unit 2100. Also, the filter units included in the largest coding unit 2100 according to one embodiment may be divided based on sizes of the coding units included in the maximum coding units 2100. Referring to FIG. 21, for example, the filter units may include a filter unit 2140 having a square shape and a depth of D, filter units 2132 and 2134 having a non-square shape and a depth of D, filter units 2112, 2114, 2116, 2152, 2154, and 2164 having a square shape and a depth of D+1, filter units 2162 and 2166 having a non-square shape and a depth of D+1, and filter units 2122, 2124, 2126, and 2128 having a square shape and a depth of D+2. The block shape information, the split shape information (depth), and the loop filtering performance information of the filtering units included in the larger coding unit 2100 may be encoded as shown in Table 1. iviA / a / zuzo / uii ooo 120 iviA / a / zuzo / uii ooo Table 1 Depth Block Shape Loop Filtering Performance Information D 0:SQUARE 0(2140) 1:NS_VER 0(2132), 1(2134) 2:NS_HOR D+1 0:SQUARE 1 (2112), 1 (2114), 0(2116), 1 (2152), 0(2154), 1(2164) 1:NS_VER 2:NS_HOR 0(2162), 1(2166) D+2 0 : SQUARE 1(2122), 0(2124), 0(2126), 0(2128) 1:NS_VER 2 : NS HOR A process for determining a plurality of coding units by repeatedly dividing a coding unit according to block shape information and block division information according to an embodiment is the same as that described with reference to FIG. 13. Loop filtering performance information of filtering units according to an embodiment indicates that loop filtering is performed on the filtering units when a flag value is 1, and indicates that loop filtering is not performed on the filtering units when a flag value is 0. With reference to Table 1, data unit information for determining filtering units that are filtered by the 121 loop filters 2040 and 2070 can all be encoded and transmitted as filter information. Because the coding units configured according to one embodiment are coding units configured to minimize an error with an original image, a high spatial correlation is expected in the coding units. Accordingly, because a filtering unit is determined based on a coding unit according to one embodiment, an operation for determining a filtering unit, separate from the determination of a coding unit, can be omitted. Also, according to one embodiment, because a filtering unit is determined based on a coding unit according to one embodiment and thus information for determining a manner of dividing the filtering unit can be omitted, a transfer bit rate of the filter information can be saved. Although in the above embodiments it is described that a filtering unit is determined based on a coding unit according to one embodiment, the filtering unit may be divided based on a coding unit to an arbitrary depth, and in this way a shape of the filtering unit may be determined to only the arbitrary depth. IVIA / a / ZUzí J / UII ooo The determination of a described filter unit 122 in the above embodiments can be applied not only to loop filtering but also to various embodiments such as deblocking filtering and adaptive loop filtering. According to one embodiment, the image decoding apparatus 100 may divide a current coding unit by using at least one of block shape information and partition shape information, and the block shape information may be predetermined to indicate using only a square shape, and the partition shape information may be predetermined to indicate that the current coding unit is not divided or is divided into 4 square coding units. That is, the coding units of the current coding unit may always have a square shape according to the block shape information, and the current coding unit may not be divided or may be divided into 4 square coding units based on the partition shape information.The image decoding apparatus 100 may obtain, by using the bit stream obtainer 110, a bit stream generated by using a predetermined encoding method that is predetermined to use only these block forms and division forms, and the apparatus. IVIA / a / ZUzí J / UII ooo 123 image decoding apparatus 100 may use only the predetermined block shapes and division shapes. In this case, because the image decoding apparatus 100 can solve a problem of compatibility with the predetermined encoding method by using a predetermined decoding method similar to the predetermined encoding method. According to one embodiment, when the image decoding apparatus 100 uses the predetermined decoding method using only the predetermined block shapes and division shapes from among various shapes that may be indicated by the block shape information and the division shape information, the block shape information indicates only a square shape and thus the image decoding apparatus 100 may not perform a process for obtaining the block shape information from the bit stream.A syntax indicating whether the predetermined decoding method is used may be used, and this syntax may be obtained from the bit stream according to data units having various forms that may include a plurality of coding units such as sequences, visual representations, slice units, and larger coding units. That is, the bit stream obtainer 110 may determine whether the syntax iviA / a / zuzo / uii ooo. 124 indicates the block shape information to be obtained from the bit stream based on the syntax indicating whether the default decoding method is used. FIGURE 23 illustrates an index according to a Z-scan order of a coding unit according to an embodiment. The image decoding apparatus 100 according to one embodiment may scan lower data units that are included in an upper data unit according to a Z-scan order. Also, the image decoding apparatus 100 according to one embodiment may sequentially access data according to a Z-scan index in an encoding unit included in a processing block or the largest encoding unit. The image decoding apparatus 100 according to one embodiment may divide a reference coding unit into at least one coding unit as described with reference to FIGS. 13 and 14. In this case, coding units having a square shape and coding units having a non-square shape may coexist in the reference coding unit. The image decoding apparatus 100 according to one embodiment may access data according to a Z-scan index included in iviA / a / zuzo / uii ooo 125 each coding unit in the reference coding unit. In this case, a method for applying a Z-scan index may vary according to whether a coding unit having a non-square shape exists in the reference coding unit. According to one embodiment, when a coding unit having a non-square shape does not exist in the reference coding unit, coding units of a lower depth in the reference coding unit may have continuous Z-scan indices. For example, according to one embodiment, a coding unit of a higher depth may include four coding units of a lower depth. The boundaries of the four coding units of the lower depth may be continuous, and the coding units of the lower depth may be scanned in a Z-scan order according to indices indicating the Z-scan order. The indices indicating the Z-scan order according to one embodiment may be set to numbers that increment according to the Z-scan order for the coding units.In this case, deeper coding units of the same depth can be scanned according to the Z-scan order. According to one modality, when at least 126 a coding unit having a non-square shape exists in the reference coding unit, the image decoding apparatus 100 may divide each of the coding units in the reference coding unit into sub-blocks, and may scan the divided sub-blocks according to the Z-scan order. For example, when a coding unit having a non-square shape in a vertical direction or a horizontal direction exists in the reference coding unit, Z-scanning may be performed by using divided sub-blocks. Also, for example, when the reference coding unit is divided into an odd number of coding units, Z-scanning may be performed by using sub-blocks. A sub-block is a coding unit that is no longer divided or a coding unit obtained by dividing an arbitrary coding unit, and may have a square shape.For example, four square-shaped sub-blocks can be divided into one square-shaped coding unit. Also, for example, two square-shaped sub-blocks can be divided into one non-square-shaped coding unit. Referring to FIGURE 23, for example, the image decoding apparatus 100 according to an iviA / a / zuzo / uii ooo 127 embodiment may scan coding units 2302, 2304, 2306, 2308, and 2310 of a lower depth in a coding unit 2300 according to a Z-scan order. The coding unit 2300 and the coding units 2302, 2304, 2306, 2308, and 2310 are respectively an upper coding unit and lower coding units. The coding unit 2300 includes coding units 2306 and 2310 having a non-square shape in a horizontal direction. The coding units 2306 and 2310 having a non-square shape have discontinuous boundaries with the coding units 2302 and 2304 that are adjacent to each other and have a square shape. Also, the coding unit 2308 has a square shape, and is a coding unit in the center when a coding unit having a non-square shape is divided into an odd number of coding units.Like the non-square shaped coding units 2306 and 2310, the coding unit 2308 has discontinuous boundaries with the adjacent square shaped coding units 2302 and 2304. When the coding unit 2300 includes the non-square shaped coding units 2306 and 2310, or the centrally located coding unit 2308, it is a coding unit having a non-square shape. 128 is divided into an odd number of coding units, because the adjacent boundaries between coding units are discontinuous, continuous Z-scan indices cannot be established. Accordingly, the image decoding apparatus 100 may continuously set Z-scan indices by dividing coding units into sub-blocks. Also, the image decoding apparatus 100 may perform continuous Z-scanning on the coding units 2306 and 2310 having a non-square shape or the coding unit 2308 located at the center of an odd number of coding units having a non-square shape. A coding unit 2320 of FIGURE 23 is obtained by dividing the coding units 2302, 2304, 2306, 2308 and 2310 in the coding unit 2300 into sub-blocks. Because a Z-scan index can be set for each of the sub-blocks and the adjacent boundaries between the sub-blocks are continuous, the sub-blocks can be scanned according to a Z-scan order. For example, in a decoding apparatus according to one embodiment, the coding unit 2308 can be divided into sub-blocks 2322, 2324, 2326, and 2328. In this case, the sub-blocks 2322 and 2324 can be scanned after data processing is performed in a sub-block 2330, and the sub-blocks 2326 and 2328 can be decoded. 129 scan after data processing is performed in a sub-block 2332. Also, sub-blocks may be scanned according to the Z scan order. In the above embodiments, data units are scanned according to a Z-scan order for data storage, data loading, and data access. Also, in the above embodiments, although data units may be scanned according to a Z-scan order, a data unit scanning order may be one of several orders such as a raster scanning order, an N-scan order, an ascending diagonal scanning order, a horizontal scanning order, and a vertical scanning order, and shall not be limited to the Z-scan order. Also, in the above embodiments, although coding units in a reference coding unit are scanned, the present disclosure is not limited thereto, and a target that is scanned may be an arbitrary block in a processing block or the largest coding unit. Also, in the above embodiments, although a block is divided into sub-blocks and scanning is performed according to a Z-scan order only when there is at least one block that has a non-square shape, 130 A block can be divided into sub-blocks and scanning can be performed according to a Z-scan order even when a block having a non-square shape does not exist for a simplified embodiment. The image decoding apparatus 100 according to an embodiment may generate prediction data by performing inter-prediction or intra-prediction on a coding unit, may generate residual data by performing inverse transformation on a transform unit included in a current coding unit, and may reconstruct the current coding unit by using the generated prediction data and the residual data. A prediction mode of a coding unit according to one embodiment may be at least one of an intra mode, an inter mode, and a hop mode. According to one embodiment, a prediction mode may be independently selected according to the coding units. When a coding unit having a 2Nx2N shape is divided into two coding units having a 2NxN shape or an Nx2N shape according to a mode, inter-mode prediction and intra-mode prediction can be performed separately in each coding unit. Also, a hopping mode can be applied to iviA / a / zuzo / uii ooo 131 coding units that have the form 2NxN or Nx2N according to a modality. The image decoding apparatus 100 according to an embodiment may allow performing bi-prediction in a hopping mode of a coding unit having an 8x4 or 4x8 shape. Because only hopping mode information about a coding unit is received in a hopping mode, the use of residual data for the coding unit is omitted. Accordingly, in this case, an accompanying dequantization and inverse transformation information can be reduced. In contrast, the image decoding apparatus 100 according to an embodiment may allow performing bi-prediction in a coding unit to which a hopping mode is applied, thereby improving decoding efficiency.Also, the image decoding apparatus 100 according to one embodiment may set a number of interpolation beats to a relatively small value during motion compensation while enabling bi-prediction to be performed in a coding unit having an 8x4 or 4x8 shape, thereby efficiently utilizing a memory bandwidth. For example, an interpolation filter having a beat number less than 8 (e.g., a 2-beat interpolation filter) may be used. 132 instead of an 8-beat interpolation filter. Also, the image decoding apparatus 100 according to an embodiment may signal intra- or inter-prediction information about each region included in a current coding unit by dividing the region in a pre-established manner (e.g., diagonal-based division). The image decoding apparatus 100 according to one embodiment may obtain a prediction shape of a current coding unit using an intra mode by using adjacent samples of the current coding unit. In this case, the intra prediction is performed by using adjacent samples that are pre-reconstructed, and the samples are referred to as reference samples. FIGURE 24 is a diagram of a reference sample for intra-prediction of a coding unit, according to an embodiment. With reference to FIGURE 24, for a coding unit 2400 where a block shape is a non-square shape, a length in a horizontal direction is w, and a length in a vertical length is h, upper reference samples w+h 2402, left reference samples w+h 2404, and an upper left reference sample 2406 are required, that is, the total number of reference samples required 133 2(w+h)+l. For the purpose of preparing a reference sample, padding can be performed in a part where the reference sample does not exist, and a reference sample filtering process can be performed for each prediction mode to reduce a quantization error included in a reconstructed reference sample. Although the number of reference samples when a block shape of a current coding unit is a non-square shape has been described in the previous embodiments, the number of reference samples applies equally even when a current coding unit is a rectangular shape. The above various embodiments describe an operation related to an image decoding method performed by the image decoding apparatus 100. An operation of the image coding apparatus 200 for performing an image coding method that corresponds to a reverse order process of the image decoding method will be described through several embodiments. FIGURE 2 is a block diagram of the image coding apparatus 200 for coding an image based on at least one of block shape information and division shape information, according to iviA / a / zuzo / uii ooo an embodiment. 134 The image coding apparatus 200 may include an encoder 220 and a bit stream generator 210. The encoder 220 may receive an input image and may encode the input image. The encoder 220 may encode the input image and may obtain at least one syntax element. The syntax element may include at least one of a skip flag, prediction mode, motion vector difference, motion vector prediction method (or index), transform quantized coefficient, coded block pattern, coded block flag, intra prediction mode, direct flag, combination flag, delta QP, reference index, prediction direction, and transform index.The encoder 220 may determine a context model based on block shape information that includes at least one of a ratio or a size of a shape, a direction, a width, and a height of a coding unit. The bitstream generator 210 may generate a bitstream based on the encoded input image. For example, the bitstream generator 210 may generate the bitstream by entropically encoding the syntax element based on the encoded input image. IVIA / a / ZUzí J / UII ooo context model. Also, the coding apparatus of 135 images 200 can transmit the bit stream to the image decoding apparatus 100. According to one embodiment, the encoder 220 of the image coding apparatus 200 may determine a shape of a coding unit. For example, the coding unit may have a square shape or a non-square shape, and information indicating the shape may be included in the block shape information. According to one embodiment, the encoder 220 may determine in what manner the coding unit is to be divided. The encoder 220 may determine a shape of at least one coding unit included in the coding unit, and the bit stream generator 210 may generate the bit stream that includes division shape information that includes information about the shape of the coding unit. According to one embodiment, the encoder 220 may determine whether the coding unit is divided or not divided. When the encoder determines that only one coding unit is included in the coding unit or the coding unit is not divided, the bit stream generator 210 may generate the bit stream including the division shape information indicating that the coding unit is not divided. IVIA / a / ZUzí J / UII ooo divides. Also, the encoder 220 can divide the unit 136 encoding into a plurality of coding units, and the bit stream generator 210 may generate the bit stream including the splitting shape information indicating that the coding unit is split into the plurality of coding units. According to one embodiment, information indicating the number of coding units into which the coding unit is to be divided or a direction in which the coding unit is to be divided may be included in the division shape information. For example, the division shape information may indicate that the coding unit is divided in at least one direction between a vertical direction and a horizontal direction or is not divided. The image coding apparatus 200 determines information about a split shape mode based on the split shape mode of the coding unit. The image coding apparatus 200 determines the context model based on at least one of the shape ratio or size, the direction, the width, and the height of the coding unit. The image coding apparatus 200 generates the information about the split shape mode for splitting the coding unit based on the context model. IVIA / a / ZUzí J / UII ooo context as the bit stream. 137 For the purpose of determining the context model, the image coding apparatus 200 may obtain an array to correspond at least one of the shape ratio or size, direction, width, and height of the coding unit to an index for the context model. The image coding apparatus 200 may obtain the index for the context model based on at least one of the shape ratio or size, direction, width, and height of the coding unit in the array. The image coding apparatus 200 may determine the context model based on the index for the context model. For the purpose of determining the context model, the image coding apparatus 200 may determine the context model further based on block shape information including at least one of a ratio or a size of a shape, a direction, a width, and a height of a contiguous coding unit adjacent to the coding unit. Also, the contiguous coding unit may include at least one of coding units located on a lower left side, a left side, an upper left side, a top side, an upper right side, a right side, or a lower right side of the 138 coding unit. Also, for the purpose of determining the context model, the image coding apparatus 200 may compare a length of a width of an upper contiguous coding unit with a length of the width of the coding unit. Also, the image coding apparatus 200 may compare a length of a height of left and right contiguous coding units with a length of the height of the coding unit. Also, the image coding apparatus 200 may determine the context model based on the comparison results. An operation of the image encoding apparatus 200 is similar to an operation of the image decoding apparatus 100 described with reference to FIGS. 13 to 34, and thus a detailed explanation thereof is not provided at this point. Hereinafter, an apparatus and a method for decoding a motion vector and an apparatus and a method for encoding a motion vector according to an embodiment are described with reference to FIGS. 25 to 36. FIGURE 25 is a block diagram illustrating a configuration of a motion vector decoding apparatus 2500, according to one embodiment. 139 Referring to FIGURE 25, the motion vector decoding apparatus 2500 according to one embodiment may include a bit stream getter 2510, a default motion vector determiner 2530, and a prediction decoder 2550. The motion vector decoding apparatus 2500 may be included in the above-described image decoding apparatus 100. For example, the bit stream getter 2510 may be included in the bit stream getter 110 of the image decoding apparatus 100 illustrated in FIG. 1 , and the default motion vector determiner 2530 and the prediction decoder 2550 may be included in the decoder 120 of the image decoding apparatus 100. In image coding and decoding, inter-prediction refers to a prediction method that uses the similarity between a current image and another image. A reference block similar to a current block in the current image is detected from a reference image that is decoded before the current image, and the distance between the coordinates of the current block and the reference block is represented by a motion vector. Also, the difference in pixel values ​​between the current block and the reference block can be iviA / a / zuzo / uii ooo 140 represent as residual data. Therefore, the information sent through inter-prediction of the current block is not image information of the current block, but can be an index, a motion vector, and residual data indicating the reference block, thereby improving coding and decoding efficiency. The motion vector decoding apparatus 2500 may determine a motion vector to reconstruct a current encoded block by using inter-prediction. A block type may be a square or rectangular shape, or it may be an arbitrary geometric shape. A block according to a modality is not limited to a data unit of a certain size, and may include the largest coding unit, a coding unit, a prediction unit, and a transformation unit among coding units according to a tree structure. The bitstream getter 2510 may obtain a bitstream including information for decoding an image. According to a prediction mode of a current frame, the bitstream may include information about at least one of a residual motion vector, a prediction motion vector, whether or not a default motion vector is determined. 141 (MV), a prediction direction (one-way prediction or two-way prediction), a reference image index, and a motion vector resolution. The default motion vector determiner 2530 may determine a default motion vector (hereinafter referred to as a default MV) of the current block. The default MV may be used to determine a prediction motion vector of the current block. For example, in a method for determining a prediction motion vector (PMV) of a current block using an MV from at least one PMV candidate block, where a PMV candidate block exists that does not have an available MV from at least the PMV candidate block, the PMV of the current block may be determined using a default MV. In other words, the default MV can be a replacement MV for a MV from the PMV candidate block used to determine the PMV of the current block. The default motion vector determiner 2530 may determine a default MV or a plurality of default MVs based on one MV of a plurality of default MV candidate blocks associated with the current block. The positions or number of the plurality of default MV candidate blocks may be 142 predetermined in the default motion vector determiner 2530. The plurality of default MV candidate blocks may include previously decoded spatial blocks and / or previously decoded temporal blocks that are associated with the current block. The spatial blocks may include at least one block spatially adjacent to the current block. The temporal blocks may include a block located at the same position as the current block in a reference picture that has a different representation order count (POC) than a POC of the current block, and at least one block spatially adjacent to the block located at the same position. FIGURE 29 illustrates spatial blocks and temporal blocks associated with a current block 2900. Referring to FIGURE 29, the spatial blocks spatially associated with the current block 2900 may include an upper left block a, an upper right block b, an upper left block c, an upper right block d, an upper left outer block e, an upper right outer block f, a lower left outer block g, a lower right outer block h, a lower left block i, a lower right block j, a lower left block k, a lower right block l, a left block m, a right block n, a 143 upper block o, and a lower block p. Also, the temporal blocks temporally associated with the current block 2900 may include a same block of position q included in a reference frame having a POC different from a POC of the current block 2900 and an adjacent block r adjacent to the same block of position q. The spatial blocks and temporal blocks associated with the current block 2900 illustrated in FIG. 29 are examples, and the plurality of default MV candidate blocks may include at least some of the blocks illustrated in FIG. The default motion vector determiner 2530 may determine a default MV of the current block by using at least some of the MVs from the plurality of default MV candidate blocks. FIGURE 30 illustrates default MV candidate blocks for determining a default MV. Referring to FIGURE 30, the default MV candidate blocks may include a left block C0, a top left block Cl, a top left block C2, a top right block C3, a top left outer block C4, and a bottom left outer block C5, relative to the current block 2900. However, the number or positions of the default MV candidate blocks illustrated are examples and are iviA / a / zuzo / uii ooo 144 can be varied within a range obvious to a person of ordinary experience in the field. According to one embodiment, the default motion vector determiner 2530 may establish a priority order with respect to the default MV candidate blocks and may determine whether or not an MV exists with respect to each of the default MV candidate blocks according to the priority order. The default motion vector determiner 2530 may, according to an order in which an MV is identified as existing, determine the MV of the default MV candidate block as the default MV. The priority order may be predetermined in the default motion vector determiner 2530, or the default motion vector determiner 2530 may determine the priority order in a certain manner. The default motion vector determiner 2530 may determine whether or not each default MV candidate block has an MV according to the priority order and may determine the MV of the default MV candidate block for which the availability of the MV is identified first, as the default MV. Also, the default motion vector determiner 2530 may determine whether or not the MV exists with respect to each default MV candidate block of IVIA / a / ZUzí J / UII ooo 145 according to the priority order, and may determine the MVs of the plurality of default MV candidate blocks as a plurality of default MVs according to the order in which the MV is identified to exist with respect to the default MV candidate block. For example, it can be assumed that the priority order is set in an order from block C0 to block C5 and that MVs exist in blocks Cl, C2, and C4. When the default motion vector determiner 2530 is to determine a default MV, the default motion vector determiner 2530 may determine the MV in block Cl having the highest MV and priority order as the default MV. Also, when the default motion vector determiner 2530 is to determine two default MVs, the default motion vector determiner 2530 may determine the MV in block Cl having the highest MV and priority order and the MV in block C2 having the second highest priority order as the two default MVs. The default motion vector determiner 2530 may change the priority order established with respect to the plurality of default MV candidate blocks by comparing a reference picture index of the current block with a reference picture index of the plurality of default MV candidate blocks. For example, the default motion vector determiner 2530 may increment the priority order of a default MV candidate block having a reference picture index that is the same as the reference picture index of the current block. When there are a plurality of default MV candidate blocks having the same reference picture index as the current block, an order among the plurality of default MV candidate blocks may conform to the predetermined priority order. For example, when the priority order is set in the order of block C0 to block C5, and the reference picture index of only block C5 is the same as the reference picture index of the current block, the priority order of block C5 can be changed to be first. Accordingly, the priority order can be changed to have the order of blocks C5, C0, C1, C2, C3, and C4. Also, for example, when the priority order is set in the order of block C0 to block C5, and the reference picture index of block C4 and the reference picture index of block C5 are the same as the reference picture index of the current block, the priority orders of blocks C4 and C5 can be incremented. Furthermore, the priority order can be changed to the order of blocks C4, C5, C0, C1, C2, and C3. IVIA / a / ZUzí J / UII ooo 147 such that the priority order of block C4 is higher than the priority order of block C5 according to the initial priority order. According to one embodiment, the default motion vector determiner 2530 may determine whether or not the reference picture index of each default MV candidate block is the same as the reference picture index of the current block according to the priority order, and may determine the MV of at least one default MV candidate block as the at least the default MV according to an order in which the reference picture index is determined to be the same as the reference picture index of the current block.When there is no default MV candidate block having the same reference picture index as the current block, the default motion vector determiner 2530 may determine whether each default MV candidate block has an MV according to the priority order, and may determine the MV of at least one default MV candidate block as at least one default MV, according to the order in which the MV is identified to exist. According to one embodiment, the default motion vector determiner 2530 may determine MVs from one or more default MV candidate blocks that have the same reference picture index as the block ινΐΛ / a / zuzo / uii ooo 148 current as one or more MVs by default, regardless of whether priority order is set or not. Also, according to one embodiment, the default motion vector determiner 2530 may select a predetermined number of default MV candidate blocks based on a size of the MVs of the default MV candidate blocks, and may determine each of the MVs of the selected default MV candidate blocks as the default MV. For example, the default motion vector determiner 2530 may select a predetermined number of default MV candidate blocks based on an order in which the default MV candidate blocks have a largest MV, and may determine each of the MVs of the selected default MV candidate blocks as the default MV.Also, for example, the default motion vector determiner 2530 may select a predetermined number of default MV candidate blocks based on an order in which the default MV candidate blocks have a similar MV, and may determine each of the MVs of the selected default MV candidate blocks as the default MV. According to one embodiment, the default motion vector determiner 2530 may determine a value obtained by combining the MVs of the plurality of 149 default MV candidate blocks, for example, an average value or an intermediate value of the MVs, as the default MV. With reference to FIGURE 30, when there are MVs in all blocks C0 through C5, the average value or the intermediate value of the MVs can be determined as the default MV. When there are MVs only in blocks C0, C1, and C2, the average value or the intermediate value of the MVs in blocks C0, C1, and C2 can be determined as the default MV. Also, according to one embodiment, the default motion vector determiner 2530 may determine the default MV corresponding to a specific address from a default MV candidate block located at the specific address based on the current block. For example, when the default motion vector determiner 2530 is for determining the default MV corresponding to a left address, the default motion vector determiner 2530 may determine the default MV based on the MV of a default MV candidate block located in the left address based on the current block. Also, for example, when the default motion vector determiner 2530 is for determining the default MV corresponding to a higher address, the default motion vector determiner 2530 may determine the default MV based on the MV of a IVIA / a / ZUzí J / UII ooo 150 default MV candidate block located at the upper address based on the current block. With reference to FIGURE 30, the default MV candidate block corresponding to the left direction may include blocks C0, Cl, C4, and C5, and the default motion vector determiner 2530 may determine the default MV corresponding to the left direction by using the MV of at least one of blocks C0, Cl, C4, and C5. The default motion vector determiner 2530 may determine whether or not the MV exists in blocks C0, Cl, C4, and C5 according to the priority order, and may determine the MV of the block for which the MV is first identified to exist as the default MV corresponding to the left direction. Also, the default MV candidate block corresponding to the upper address may include blocks C2, C3, and C4, and the default motion vector determiner 2530 may determine the default MV corresponding to the upper address by using the MV of at least one of blocks C2, C3, and C4. The default motion vector determiner 2530 may determine whether or not the MV exists in blocks C3, C3, and C4 according to the order of priority, and may determine the MV of the block for which the MV is first identified to exist as the default MV corresponding to the upper address. IVIA / a / ZUzí J / UII ooo 151 upper management. The default MV corresponding to a specific address may be assigned to a PMV block that is unavailable, as described later. In this document, the type of the assigned default MV may be different depending on the address in which the PMV candidate block is located, based on the current block. According to one embodiment, the default motion vector determiner 2530 may determine, as the default MV of the current block, the MV of a default MV candidate block from among at least the default MV candidate block, the default MV candidate block that is at a location most frequently selected for a PMV in a previously decoded visual representation, a previously decoded slice IVIA / a / ZUzí J / UII ooo or the largest previously decoded coding unit. For example, when the block which is most frequently selected as the PMV in the previously decoded visual representation of the left block C0, the upper left block Cl, the upper left block C2, the upper right block C3, the upper left outer block C4 and the lower left outer block C5 illustrated in FIGURE 30 is the left block C0, the default motion vector determiner 2530 can determine the MV by 152 default by using the MV of the block C0. When a plurality of default MVs are to be determined, the default motion vector determiner 2530 may select a plurality of default MV candidate blocks according to an order in which the default MV candidate blocks are selected as the PMV in the previously decoded display, slice, or largest coding unit, and may determine the plurality of default MVs by using the MVs of the selected default MV candidate blocks. According to one embodiment, the default motion vector determiner 2530 may determine a default MV before determining a PMV with respect to a current coded block by using inter-prediction. Alternatively, based on the determination of the availability of a PMV candidate block described later, the default MV may be determined when necessary. Alternatively, when the bit stream obtained by the bit stream obtainer 2510 includes information determining the default MV with respect to the current block, the default motion vector determiner 2530 may determine the default MV with respect to the current block. According to one embodiment, when the default motion vector determiner 2530 iviA / a / zuzo / uii ooo 153 determines the default MV by using the MV of at least one default MV candidate block based on a certain criterion from among the plurality of default MV candidate blocks, the default motion vector determiner 2530 can intactly determine the MV of at least the default MV candidate block as the Default MV, or you can change the MV of at least the default MV candidate block and determine the changed MV as the default MV. According to one embodiment, when the default motion vector determiner 2530 determines the default MV by using the MV of at least one default MV candidate block selected based on a certain criterion from among the plurality of default MV candidate blocks, the default motion vector determiner 2530 may scale the MV of at least the default MV candidate block by taking into account the reference picture index of the current block and determine the scaled MV as the default MV. According to one embodiment, the default motion vector determiner 2530 may determine the default MV of the current block by using the MV derived via the decoder-side MV derivation (DMVD). The DMVD may include, for example, a template matching method, a iviA / a / zuzo / uii ooo method, and a template matching method. 154 bilateral equalization. The prediction decoder 2550 may determine a PMV of the current block by using an MV of at least one PMV candidate block. According to one embodiment, the PMV of the current block may include a previously decoded spatial block and / or a previously decoded temporal block associated with the current block. At least one PMV candidate block may be selected from among the blocks spatially associated with the current block and the blocks temporally associated with the current block illustrated in FIG. 29). The location and number of at least one PMV candidate block used to determine the PMV of the current block may be the same as the location and number of the default MV candidate blocks used to determine the default MV described above. According to one embodiment, at least one PMV candidate block and at least one default MV candidate block may be different from each other in terms of at least one of their location and number. The number and location of the PMV candidate blocks may be predetermined in the prediction decoder 2550 or may be determined by the prediction decoder unit 2550 for a given iviA / a / zuzo / uii ooo 155 visual representation, a slice unit, or a block unit, based on a predetermined criterion. According to one embodiment, the number and location of candidate PMV blocks may be determined based on information included in the bit stream, for example, information about a MV resolution of the current block described below. The prediction decoder 2550 may determine the availability of an MV of at least the PMV candidate block, and when it is determined that a PMV candidate block is not available, the prediction decoder 2550 may determine the PMV of the current block by using the default MV. According to one embodiment, the availability of the MV of the PMV candidate block may be determined based on at least one of whether or not an MV exists in the PMV candidate block and whether or not the MV is the same as an MV of another PMV candidate block that was previously determined to be available. When a block is intra-predicted, it may be determined that there is no MV in the block. Also, in determining availability, a case where one MV is the same as another MV may include a case where both the MV and a reference image index are the same. For example, when there is no MV in any block 156 PMV candidate, it may be determined that the PMV candidate block is unavailable. Also, for example, when a MV in some PMV candidate block is the same as a MV in another PMV candidate block that was previously determined to be available, it may be determined that the PMV candidate block is unavailable. Determining availability based on whether or not the MV is the same between them may indicate the application of a type of pruning. According to one embodiment, the prediction decoder 2550 may construct, based on the availability determination, a prediction candidate list including a predetermined number of MV prediction candidates of each of at least the PMV candidate block. Also, the prediction decoder 2550 may determine the PMV of the current block by using one or more prediction candidates from among the prediction candidates included in the prediction candidate list. The prediction decoder 2550 may determine the PMV of the current block by using one or more prediction candidates identified from information included in the bit stream from among the prediction candidates included in the prediction candidate list. For example, the prediction decoder 2550 may intactly determine some candidate of IVIA / a / ZUzí J / UII ooo 157 prediction as the PMV of the current block or may change the prediction candidate and determine the changed prediction candidate as the PMV of the current block. Also, the prediction decoder 2550 may determine a value obtained by combining the plurality of prediction candidates, for example, an average value or an intermediate value of the plurality of prediction candidates, as the PMV of the current block. The prediction decoder 2550 may construct the prediction candidate list by determining the MV availability of each PMV candidate block. For example, the prediction decoder 2550 may determine the availability of each PMV candidate block according to a priority order. Referring to FIG. 31, when the priority order is set to an order of blocks A0, A1, B0, B1, B2, C3, and H, and when the block A0 having the highest priority order includes an MV, the MV of the block A0 may be included in the prediction candidate list as the prediction candidate. Then, when there is no MV in the block A1 having the second highest priority order, or even when there is an MV in the block A1 having the second highest priority order, when the MV is the same as the MV of the block A0 already included in the prediction candidate list, it may be determined that the block A1 is unavailable, and the MV is determined to be the same as the MV of the block A0. 158 may determine the availability of block B0 having the following priority order. The prediction decoder 2550 may determine the availability of each of blocks A0 to H according to the priority order, until the prediction candidate list is constructed. After the prediction decoder 2550 constructs the prediction candidate list by determining the availability of each of blocks A0 to H, when the number of prediction candidates included in the prediction candidate list is less than a predetermined number, the prediction decoder 2550 may add the default MV to the prediction candidate list. For example, when the number of prediction candidates included in the prediction candidate list is 3, and when a single prediction candidate is included in the prediction candidate list constructed based on the availability determination, the prediction decoder 2550 may add two default MVs to the prediction candidate list. Also, when two prediction candidates are included in the prediction candidate list constructed based on the availability determination, the prediction decoder 2550 may add one default MV to the prediction candidate list. iviA / a / zuzo / uii ooo 159 The number of prediction candidates included in the prediction candidate list may be predetermined. According to one embodiment, the default motion vector determiner 2530 may determine the default MVs from numbers corresponding to the predetermined number of prediction candidates included in the prediction candidate list. According to one embodiment, the prediction decoder 2550 may determine the availability of each of the PMV candidate blocks and assign the default MV to a PMV candidate block that was determined to be unavailable. The prediction decoder 2550 may then construct the prediction candidate list according to the priority order of the PMV candidate blocks. For example, the prediction decoder 2550 may determine the availability of blocks A0 through H of FIG. 31 , and when it is determined that block A11 is unavailable, it may assign the default MV to block A11. The prediction decoder 2550 may then include the MV of each of blocks A0 through H in the prediction candidate list according to the priority order. The prediction decoder 2550 may determine the PMV of the current block by using at least one prediction candidate from the list of iviA / a / zuzo / uii ooo 160 prediction candidates including the default MV or the prediction candidate list that does not include the default MV. In an embodiment in which the PMV of the current block is determined, the prediction decoder 2550 may determine the PMV of the current block based on the MV of at least one PMV candidate block at a predetermined location. The prediction decoder 2550 may determine the availability of at least the PMV candidate block at the predetermined location and may assign the default MV to a PMV candidate block that was determined to be unavailable. In this embodiment, assigning the detected MV to the PMV candidate block may indicate using the detected MV as the MV of the PMV candidate block. As illustrated in FIG. 32, when the PMV of the current block is determined as a value obtained by combining an MV of a DI block, an MV of a D2 block, and an MV of a D3 block, and when the MV does not exist in the D2 block, the default MV may be assigned as the MV of the D2 block. According to one embodiment, the default motion vector determiner 2530 may determine the same number of default MVs as the number of PMV candidate blocks at the predetermined location. Also, according to one modality, the 161 Prediction decoder 2550 may determine the PMV of the current block by using an MV from a PMV candidate block at a predetermined location. In this case, when the PMV candidate block is not determined to be available, prediction decoder 2550 may assign the default MV to the PMV candidate block. Prediction decoder 2550 may either intactly determine the default MV assigned to the PMV candidate block as the PMV of the current block, or may change the default MV and determine the changed default MV as the PMV of the current block. According to one embodiment, the prediction decoder 2550 may assign the default MV to a PMV candidate block that is unavailable from among the PMV candidate blocks at the predetermined location. When there are a plurality of PMV candidate blocks that are unavailable, the prediction decoder 2550 may assign a plurality of default MVs to the plurality of PMV candidate blocks that are unavailable, respectively. For example, in FIGURE 32, in the method for determining the PMV of the current block by using the MV of the DI block, when there is no MV in the DI block, the prediction decoder 2550 may assign the default MV to the DI block. Also, in the method for determining iviA / a / zuzo / uii ooo 162 the PMV of the current block by using the MVs of the DI, D2 and D3 blocks, when there are no MVs in the DI and D2 blocks, the prediction decoder 2550 may assign default MVs to the DI and D2 blocks, respectively. When the default MV is assigned to the PMV candidate block that has no availability, a location of the PMV candidate block may be considered. As described above, the default motion vector determiner 2530 may determine the default MV corresponding to a specific address from the default MV candidate block located at the corresponding specific address based on the current block. The prediction decoder 2550 may assign a default MV corresponding to the PMV candidate block by taking into account the address at which the PMV candidate block that has no availability is located based on the current block. For example, when there is no MV in block DI located at a left address based on the current block of FIGURE 32, the prediction decoder 2550 may assign to block DI a default MV determined corresponding to the left address, and when there is no MV in block D2 located at an upper address based on the current block, the prediction decoder 2550 may assign to block DI a default MV determined corresponding to the left address. 2550 can assign to block D2 a MV default iviA / a / zuzo / uii ooo 163 determined in correspondence to the upper address. When there is no MV in block D3, prediction decoder 2550 may assign to block D3 the default MV determined in correspondence to the upper address, or a value determined by combining at least some default MVs from a plurality of default MVs. According to one embodiment, the number and a type of at least the above-described PMV candidate block may be determined based on the motion vector resolution (hereinafter referred to as MVR) of the current block. The prediction decoder 2550 may directly determine the MVR of the current block based on a predetermined condition, or may determine the MVR of the current block with reference to information included in the bit stream obtained by the bit stream getter 2510. According to one embodiment, the bitstream getter 2510 may obtain information about the MVR for each inter-predicted coding unit. FIG. 36 illustrates a syntax for obtaining information about an MVR from a bitstream. Referring to FIGURE 36, when a cut that includes a current coding unit in a sentence a is not a cut 1, cu_skip_flag is extracted into a sentence b. cu skip flag indicates whether a skip mode is applied to the 164 current coding unit. When it is verified that the skip mode is applied in a sentence c, the current coding unit is processed in the skip mode. When it is verified that the skip mode is not applied in a sentence d, pred_mode_flag is extracted in a sentence e. pred_mode_flag indicates whether the current coding unit is intra-predicted or inter-predicted. When the current coding unit is not intra-predicted, that is, inter-predicted in a sentence f, pred_mvr_idx is extracted in a sentence g. pred_mvr_idx is an index indicating an MVR of the current coding unit, and an MVR corresponding to each index is as shown in Table 2. Table 2 MVR index 0 1 2 3 4 Resolution (R) in peí 1 / 4 1 / 2 1 2 4 The MVR of the current block may indicate a degree of accuracy of a pixel position that may be indicated by an MV of the current block from among pixels included in a reference image (or an interpolated reference image). The MVR of the current block may be selected from at least one candidate MVR. The at least one candidate MVR may include, for example, at least one of a 1 / 8 pixel unit MVR, a 1 / 4 pixel unit MVR, a 1 / 2 pixel unit MVR, a 1 pixel unit MVR, a 2 pixel unit MVR, 165 a 4-pixel unit MVR and an 8-pixel unit MVR, but is not limited to them. The number and type of PMV candidate blocks used to determine the PMV of the current block may be predetermined according to a type of MVR of the current block. For example, when the MVR of the current block is the MVR of a 1 / 4 pixel unit, the PMV candidate block may include a left block and an upper block, and when the MVR of the current block is the MVR of a 1 pixel unit, the PMV candidate block may include a lower left block. Also, when the MVR of the current block is the MVR of a 2 pixel unit, the PMV candidate block may include a right block. Similarly, when determining the MVR of the current block, the type and number of PMV candidate blocks used to determine the PMV may be automatically determined. According to one embodiment, the number of PMV candidate blocks used to determine the PMV with respect to each MVR may be 1.However, a PMV candidate block location may be different from each other with respect to each MVR. When the MVR of the current block is determined and the PMV candidate block is determined according to the determined MVR, the prediction decoder 2550 may determine the MV availability of each of the PMV candidate blocks as described above. IVIA / a / ZUzí J / UII ooo 166 Also, the prediction decoder 2550 may assign the default MV as the MV of the PMV candidate block that was determined to be unavailable, and may determine the PMV of the current block. When the default MV is assigned to the PMV candidate block, the prediction decoder 2550 may compare a minimum MVR from among the selectable candidate MVRs with respect to the current block with the MVR of the current block to set the default MV. The default MV is determined from the MV of the default MV candidate block. The MV of the default MV candidate block is predicted to indicate the pixel coordinates in an interpolated image according to the minimum MVR, and in this way, the default MV can be set to correspond to the MVR of the current block. When the number of PMV candidate blocks used to determine the PMV according to the MVR of the current block is one, and the default MV is assigned to the PMV candidate block because it is determined that the PMV candidate block is unavailable, the default MV may need to be adjusted. When the number of PMV candidate blocks used to determine the PMV is one and the PMV candidate block is available, and when the number of PMV candidate blocks used to determine the PMV is more than one, and one or more of the iviA / a / zuzo / uii ooo 167 If a plurality of PMV candidate blocks are available, the MVs of the available PMV candidate blocks may be used to determine the PMV. Thus, the MV of the PMV candidate block determined to be available may also need to be set as the default MV. A process for setting the default MV will be described in detail by reference to FIGURES 33A through 35. When the PMV of the current block is determined, the prediction decoder 2550 may obtain an MV of the current block from the PMV. When a prediction mode of the current block is a skip mode or a combination mode, the prediction decoder 2550 may determine the PMV as the MV of the current block, and when the prediction mode of the current block is an advanced motion vector prediction (AMVP) mode, the prediction decoder 2550 may obtain the MV of the current block by combining the residual MV and the PMF. Also, the prediction decoder 2550 may upscale a residual MV obtained from a bit stream by comparing the MVR of the current block with the minimum MVR, and may obtain the MV of the current block by combining the downscaled residual MV and the PMV. Upscaling IVIA / a / ZUzí J / UII ooo 168 scale of the residual MV will be described later. FIGURE 26 is a flowchart for describing a method for decoding an MV, according to an embodiment. In operation S2610, the motion vector decoding apparatus 2500 may determine a PMV of a current block. The motion vector decoding apparatus 2500 may determine the PMV of the current block by using at least one PMV candidate block associated with the current block. As described above, the motion vector decoding apparatus 2500 may determine the availability of an MV of at least the PMV candidate block. When there is a PMV candidate block that is determined to be unavailable, the motion vector decoding apparatus 2500 may determine the PMV of the current block by using the default MV determined from a plurality of default MV candidate blocks. When determining an MVR of the current block, the motion vector decoding apparatus 2500 may determine the PMV of the current block by using a default MV set according to the MVR of the current block iviA / a / zuzo / uii ooo. 169 In operation S2620, the motion vector decoding apparatus 2500 may obtain the MV of the current block based on the PMV of the current block. The motion vector decoding apparatus 2500 may obtain the PMV of the current block as the MV of the current block, or may obtain a result of combining the PMV with the residual MV as the MV of the current block. According to one embodiment, when determining the MVR of the current block, the motion vector decoding apparatus 2500 may selectively upscale the residual MV and then obtain the MV of the current block by combining the selectively upscaled residual MV with the PMV. FIGURE 27 is a block diagram illustrating a configuration of a motion vector coding apparatus 2700, according to one embodiment. 27 , the motion vector coding apparatus 2700 according to one embodiment may include a default motion vector determiner 2710, a prediction encoder 2730, and a bit stream generator 2750. The motion vector coding apparatus 2700 may be included in the image coding apparatus 200 described above. For example, the default motion vector determiner 2710 and the prediction encoder 2730 may be included in the image coding apparatus 200 described above. 170 2730 of the motion vector coding apparatus 2700 may be included in the encoder 220 of the image coding apparatus 200, and the bit stream generator 2750 of the motion vector coding apparatus 2700 may be included in the bit stream generator 210 of the image coding apparatus 200. The default motion vector determiner 2710 may determine a default MV of a current block. The default MV may be used to determine a prediction motion vector of the current block. For example, in a method for determining a PMV of the current block using an MV from at least one PMV candidate block, when there is a PMV candidate block that does not have an available MV from among at least the PMV candidate block, the PMV of the current block may be determined using the default MV. The default motion vector determiner 2710 may determine a default MV or a plurality of default MVs based on one MV of a plurality of default MV candidate blocks associated with the current block. The positions or number of the plurality of default MV candidate blocks may be IVIA / a / ZUzí J / UII ooo default in motion vector determinator 171 default 2710. The plurality of default MV candidate blocks may include pre-coded spatial blocks and / or pre-coded temporal blocks that are associated with the current block. The spatial blocks may include at least one block spatially adjacent to the current block. The temporal blocks may include a block located at the same position as the current block in a reference image that has a display order count (POC) different from a POC of the current block, and at least one block spatially adjacent to the block located at the same position. According to one embodiment, the default motion vector determiner 2710 may establish a priority order with respect to the default MV candidate blocks and may determine whether or not an MV exists with respect to each of the default MV candidate blocks according to the priority order. The default motion vector determiner 2710 may determine at least one default MV based on the MV of at least one default MV candidate block, according to an order in which the MV is identified as existing. The default motion vector determiner 2710 can determine whether each MV candidate block by 172 default has or does not have an MV according to the priority order and can determine the MV of the default MV candidate block for which the availability of the MV is identified first, as the default MV. Also, the default motion vector determiner 2710 may determine whether or not the MV exists with respect to each default MV candidate block according to the priority order, and may determine the MVs of the plurality of default MV candidate blocks as a plurality of default MVs according to the order in which the MV is identified to exist with respect to the default MV candidate block. The default motion vector determiner 2710 may change the priority order that is set with respect to the plurality of default MV candidate blocks by comparing a reference picture index of the current block with a reference picture index of the plurality of default MV candidate blocks. For example, the default motion vector determiner 2710 may increment the priority order of a default MV candidate block that has a reference picture index that is the same as the reference picture index of the current block. When there are a plurality of default MV candidate blocks that have the same reference picture index as the current block, a iviA / a / zuzo / uii ooo 173 order among the plurality of candidate blocks of MV by default can meet the predetermined priority order. According to one embodiment, the default motion vector determiner 2710 may determine whether or not the reference picture index of each default MV candidate block is the same as the reference picture index of the current block according to the priority order, and may determine the MV of at least one default MV candidate block as the at least one default MV according to an order in which the reference picture index is determined to be the same as the reference picture index of the current block.When there is no default MV candidate block having the same reference picture index as the current block, the default motion vector determiner 2710 may determine whether each default MV candidate block has an MV according to the priority order, and may determine the MV of at least one default MV candidate block as the at least one default MV according to the order in which the MV is identified to exist. According to one embodiment, the default motion vector determiner 2710 may determine the MVs of one or more default MV candidate blocks having the same reference picture index as the current block. 174 as the default MVs, regardless of whether priority order is set or not. Also, according to one embodiment, the default motion vector determiner 2710 may select a predetermined number of default MV candidate blocks based on a size of the MVs of the default MV candidate blocks, and may determine MVs from the selected predetermined number of default MV candidate blocks as the default MV. For example, the default motion vector determiner 2710 may select a predetermined number of default MV candidate blocks based on an order in which the default MV candidate blocks have the largest MV, and may determine MVs from the selected predetermined number of default MV candidate blocks as the default MV.Also, for example, the default motion vector determiner 2710 may select a predetermined number of default MV candidate blocks based on an order in which the default MV candidate blocks have a smallest MV, and may determine the MVs of the selected predetermined number of default MV candidate blocks as the default MV. According to one embodiment, the default motion vector determiner 2710 may determine an iviA / a / zuzo / uii ooo 175 value obtained by combining the MVs of the plurality of default MV candidate blocks, for example, an average value or an intermediate value of the MVs, such as the default MV. Also, according to one embodiment, the default motion vector determiner 2710 may determine the default MV corresponding to a specific direction from a default MV candidate block located at the specific direction based on the current block. For example, when the default motion vector determiner 2710 is for determining the default MV corresponding to a left direction, the default motion vector determiner 2710 may determine the default MV based on the MV of a default MV candidate block located in the left direction based on the current block.Also, for example, when the default motion vector determiner 2710 is to determine the default MV corresponding to a higher address, the default motion vector determiner 2710 may determine the default MV based on the MV of a default MV candidate block located at the higher address based on the current block. According to one embodiment, the default motion vector determiner 2710 may determine, as 176 the default MV, the MV of a default MV candidate block from among at least the default MV candidate block, the default MV candidate block is at a location most frequently selected for a PMV in a previously encoded visual representation, a previously encoded slice, or the largest coding unit previously encoded. When a plurality of default MVs are to be determined, the default motion vector determiner 2710 may select a plurality of default MV candidate blocks according to an order in which the default MV candidate blocks are selected as the PMV in the previously encoded visual representation, slice, or largest coding unit, and may determine the plurality of default MVs by using the MVs of the selected default MV candidate blocks. According to one embodiment, the default motion vector determiner 2710 may determine a default MV before determining a PMV with respect to a current block. Alternatively, based on the determination of the availability of a PMV candidate block described below, the default MV may be determined as needed. According to one embodiment, when the default motion vector determiner 2710 iviA / a / zuzo / uii ooo 177 determines the default MV by using the MV of at least one default MV candidate block selected based on a certain criterion from among the plurality of default MV candidate blocks, the default motion vector determiner 2710 may intactly determine the MV of at least the default MV candidate block as the default MV, or may change the MV of at least the default MV candidate block and determine the changed MV as the default MV. According to one embodiment, when the default motion vector determiner 2710 determines the default MV by using the MV of at least one default MV candidate block selected based on a certain criterion from among the plurality of default MV candidate blocks, the default motion vector determiner 2710 may scale the MV of at least the default MV candidate block by taking into account the reference picture index of the current block and determine the scaled MV as the default MV. According to one embodiment, the default motion vector determiner 2710 may determine the default MV of the current block by using an MV derived via DMVD. The DMVD may include, for example, a template matching method or a bilateral matching method. In general, a motion vector determining apparatus 178 encoding includes a decoding apparatus, and in this way, the default motion vector determiner 2710 of the motion vector encoding apparatus 2700 can also determine the MV through the DMVD. The prediction encoder 2730 may determine the MV of the current block. According to one embodiment, the prediction encoder 2730 may interpolate a reference image for inter-prediction of the current block, detect a block that is most similar to the current block in the reference image, and determine a distance between coordinates of the current block and a reference block as the MV of the current block. According to one embodiment, the prediction encoder 2730 may determine an MVR of the current block and determine the MV according to the determined MVR. The prediction encoder 2730 may determine, as the MVR of the current block, any candidate MVR from among at least one selectable candidate MVR with respect to the current block. The prediction encoder 2730 may interpolate the reference picture according to a minimum MVR from among at least the selectable candidate MVRs with respect to the current block and may determine the MV of the current block by using the MVR. For example, when the selectable candidate MVR with respect to the current block includes an MVR of a unit of IVIA / a / ZUzí J / UII ooo 179 1 / 4 pixel, an MVR of a 1 / 2 pixel unit, an MVR of a 1 pixel unit, and an MVR of a 2 pixel unit, and the MVR of the 1 pixel unit is selected as the MVR of the current block, the prediction encoder 2730 may interpolate the reference image by using the 1 / 4 pixel unit which has the minimum MVR and may determine the MV by using the 1 pixel unit in the interpolated reference image. The prediction encoder 2730 may determine a PMV of the current block for the purpose of encoding the MV of the current block. According to one embodiment, the PMV of the current block may be determined from at least one PMV candidate block that includes spatial blocks and / or temporal blocks associated with the current block. The number and location of the PMV candidate blocks may be predetermined in the prediction encoder 2730 or may be determined by the prediction encoder 2730 for a display unit, a slice unit, or a block unit. According to one embodiment, the number and location of the PMV candidate blocks may be determined according to the MVR of the current block. The prediction encoder 2730 may determine the availability of an MV from at least the PMV candidate block, and when there is a PMV candidate block IVIA / a / ZUzí J / UII ooo 180 that was determined to be unavailable, the prediction encoder 2730 may determine the PMV of the current block by using the default MV. According to one embodiment, the availability of the MV of the PMV candidate block may be determined based on at least one of whether or not an MV exists in the PMV candidate block and whether or not the MV is the same as an MV of another PMV candidate block that was previously determined to be available. According to one embodiment, the prediction encoder 2730 may construct, based on the availability determination, a prediction candidate list that includes a predetermined number of PMV prediction candidates for each of at least one PMV candidate block. Also, the prediction encoder 2730 may determine the PMV of the current block by using one or more prediction candidates from among the prediction candidates included in the prediction candidate list. For example, the prediction encoder 2730 may intactly determine some prediction candidate as the PMV of the current block, or it may change the prediction candidate and may determine the changed prediction candidate as the PMV of the current block. Also, IVIA / a / ZUzí J / UII ooo the prediction encoder 2730 can determine a value 181 obtained by combining the plurality of prediction candidates, for example, an average value or an intermediate value of the plurality of prediction candidates, such as the PMV of the current block. The prediction encoder 2730 may construct the prediction candidate list by determining the availability of the MV of each PMV candidate block. For example, the prediction encoder 2730 may determine the availability of each PMV candidate block according to a priority order. With reference to FIG. 31, when the priority order is set to an order of blocks A0, A1, B0, B1, B2, C3, and H, and when the block A0 having the highest priority order includes an MV, the MV of the block A0 may be included in the prediction candidate list as the prediction candidate.Then, when there is no MV in block A11 having the second highest priority order, or even when there is an MV in block A11 having the second highest priority order, when the MV is the same as the MV of block A0 already included in the prediction candidate list, it may be determined that block A11 is unavailable, and the availability of block B0 having the next highest priority order may be determined. The prediction encoder 2730 may determine the availability of each of blocks A0 to H according to the priority order, up to iviA / a / zuzo / uii ooo. 182 the prediction candidate list is constructed. After the prediction encoder 2730 constructs the prediction candidate list by determining the availability of each of the blocks A0 through H, when the number of prediction candidates included in the prediction candidate list is less than a predetermined number, the prediction decoder 2550 may include the default MV in the prediction candidate list. According to one embodiment, the prediction encoder 2730 may determine the availability of each of the PMV candidate blocks and assign the default MV to a PMV candidate block that was determined to be unavailable. Then, the prediction encoder 2730 may construct the prediction candidate list according to the priority order of the PMV candidate blocks. The number of prediction candidates that are included in the prediction candidate list may be predetermined. According to one embodiment, the default motion vector determiner 2710 may determine the number of default MVs that correspond to the predetermined number of prediction candidates that are included in the prediction candidate list. The prediction encoder 2730 may determine the PMV of the current block by using at least one iviA / a / zuzo / uii ooo 183 prediction candidate from the prediction candidate list that includes the default MV or the prediction candidate list that does not include the default MV. According to one embodiment, the prediction encoder 2730 may determine the PMV of the current block based on an MV of at least one PMV candidate block at a predetermined location. The prediction encoder 2730 may determine the availability of at least the PMV candidate block at the predetermined location and may assign the default MV as the MV of a PMV candidate block that was determined to be unavailable. As illustrated in FIG. 32 , when the PMV of the current block is determined as a value obtained by combining an MV of a DI block, an MV of a D2 block, and an MV of a D3 block, and when the MV does not exist in the D2 block, a default MV may be assigned as the MV of the D2 block. Also, according to one embodiment, the prediction encoder 2730 may determine the PMV of the current block by using an MV from a PMV candidate block at a predetermined location. In this case, when the PMV candidate block is not determined to be available, the prediction encoder 2730 may assign the default MV to the PMV candidate block. The prediction encoder 2730 may intactly determine the MV. IVIA / a / ZUzí J / UII ooo 184 default assigned to the PMV candidate block as the PMV of the current block or you can change the default MV and determine the changed default MV as the PMV of the current block. According to one embodiment, the prediction encoder 2730 may assign the default MV to a PMV candidate block that has no availability from among the PMV candidate blocks at the predetermined location, and when there are a plurality of PMV candidate blocks that have no availability, the prediction decoder 2550 may assign a plurality of default MVs to the plurality of PMV candidate blocks that have no availability, respectively. According to one embodiment, the default motion vector determiner 2530 may determine the same number of default MVs as the PMV candidate blocks at the predetermined location. When the default MV is assigned to the PMV candidate block that has no availability, a PMV candidate block location may be considered. As described above, the default motion vector determiner 2710 may determine the default MV corresponding to a specific address from the default MV candidate block located at the corresponding specific address based on the iviA / a / zuzo / uii ooo block. 185 current. The prediction encoder 2730 may assign a default MV corresponding to the PMV candidate block by taking into account the address at which the PMV candidate block that does not have an MV is located based on the current block. When the MV and PMV of the current block are determined, the prediction encoder 2730 may obtain a residual MV which is a difference between the MV and the PMV of the current block, based on a prediction mode of the current block. When the prediction mode of the current block is a skip mode or a combination mode, the prediction encoder 2730 may skip obtaining the residual MV, and when the prediction mode of the current block is an AMVP mode, the prediction encoder 2730 may obtain the residual MV. According to one embodiment, the prediction encoder 2730 may generate information about the PMV of the current block. For example, when the PMV of the current block is determined from a predetermined number of prediction candidate lists, the prediction encoder 2730 may generate information indicating which prediction candidate among the predetermined number of prediction candidates is used as the PMV of the current block. When the PMV of the current block is determined to IVIA / a / ZUzí J / UII ooo 186 from the MV of the PMV candidate block at a predetermined location, the prediction encoder 2730 may skip generating information about the PMV. That is, because the motion vector decoding apparatus 2500 may also determine the PMV by using the same PMV candidate block at the predetermined location, for the purpose of determining the MV of the current block. According to one embodiment, the prediction encoder 2730 may generate information indicating that the default MV is determined for the purpose of determining the PMV of the current block. For example, when the default MV is determined by the default motion vector determiner 2710, flag 1 may be generated, and when the determination of the default MV is omitted, flag 0 may be generated. According to one embodiment, the prediction encoder 2730 may generate information indicating the MVR of the current block. The bit stream generator 2750 may generate a bit stream that includes at least one of information corresponding to the residual MV, information about the PMV, information about whether the default MV is determined or not, information about the MVR of the current block, information about a prediction address, and information about the PMV of the current block. IVIA / a / ZUzí J / UII ooo 187 (a directional direction or a bilateral direction) and information about the reference image index generated by the prediction encoder 2730. FIGURE 28 is a flowchart for describing a method for encoding an MV, according to an embodiment. In operation S2810, the motion vector coding apparatus 2700 may determine the MV of the current block. The motion vector coding apparatus 2700 may find a reference block that is most similar to the current block in a reference image and may determine the MV indicating a distance between coordinates of the reference block and the current block. According to one embodiment, when determining an MVR of the current block, the motion vector coding apparatus 2700 may determine the MV according to the MVR of the current block in an interpolated image according to the minimum MVR. In operation S2820, the motion vector coding apparatus 2700 may determine a PMV of the current block. The motion vector coding apparatus 2700 may determine the PMV of the current block by using an MV of at least one candidate block of 188 PMV. As described above, the motion vector coding apparatus 2700 may determine the availability of the MV of at least the PMV candidate block. When there is a PMV candidate block that is determined to be unavailable, the motion vector coding apparatus 2700 may determine the PMV of the current block by using a default MV determined from a plurality of default MV candidate blocks. When determining the MVR of the current block, the motion vector coding apparatus 2700 may determine the PMV of the current block by using a default MV set according to the MVR of the current block. Hereinafter, a process in which the default MV is adjusted when determining the MVR of the current block will be described with reference to FIGS. 33A through 35. As described above, when any candidate MVR from among at least one selectable candidate MVR with respect to the current block is selected as the MVR of the current block, the default MV may have to be adjusted according to a resolution of the current iviA / a / zuzo / uii ooo block, when the default MV is used to determine the 189 PMV of the current block. FIGS. 33A-33D illustrate pixel positions that may be indicated by MVs according to an MVR of a 1 / 4 pixel unit, an MVR of a 1 / 2 pixel unit, an MVR of a 1 pixel unit, and an MVR of a 2 pixel unit, when a selectable minimum MVR with respect to the current block is the MVR of the 1 / 4 pixel unit. Figures 33A-33D respectively illustrate coordinates (marked by black squares) of pixels that may be indicated by MVs of the MVR of the 1 / 4 pixel unit, the MVR of the 1 / 2 pixel unit, the MVR of the 1 pixel unit and the MVR of the 2 pixel unit based on the coordinates (0, 0). When the minimum MVR is the MVR of the 1 / 4 pixel unit, the pixel coordinates that can be indicated by the MV of the MVR of the 1 / 4 pixel unit become (a / 4, b / 4) (a and b are integers), the pixel coordinates that can be indicated by the MV of the MVR of the 1 / 2 pixel unit become (2c / 4, 2d / 4) (c and d are integers), the pixel coordinates that can be indicated by the MV of the MVR of the 1 pixel unit become (4e / 4, 4f / 4) (e and f are integers), and the pixel coordinates that can be indicated by the MV of the MVR of the 2 pixel unit become (8g / 4, 8h / 4) (g and h are integers). That is, when the minimum MVR iviA / a / zuzo / uii ooo 190 has a unit of 2m(m is an integer) pixels, the coordinates of a pixel that can be indicated by an MVR of a unit of 2n(n is an integer) pixels become (2ri-m 1i / 2-rn, 2r,-mlj / 2-rn) (i and j are integers). Although the MV is determined according to a specific MVR, the MV is represented by coordinates in an interpolated image according to the unit of 1 / 4 pixel which corresponds to a minimum MVR. In one embodiment, because the motion vector coding apparatus 2700 determines the MV in the interpolated image according to the minimum MVR, for the purpose of representing the MV by using an integer, the MV of an integer unit may be represented by multiplying the MV by a reciprocal of a pixel unit value of the minimum MVR, for example, 2-m when the minimum MVR has a unit of 2n (m is an integer) pixels. The MV of the integer unit multiplied by 2-m may be used in the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500. When the MV of the MVR of the unit of 1 / 2 pixel starting from the coordinates (0, 0) indicates the coordinates (2 / 4, 6 / 4) and the minimum MVR has the unit of 1 / 4 pixel, the motion vector coding apparatus 2700 can determine (2, 6), which is obtained by 191 multiply the MV by an integer 4, as an MV. FIGURE 34 is a diagram to describe a method for setting a default MV. The motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may set the default MV that is used as a PMV of a current block when an MVR of the current block is greater than a minimum MVR from among selectable candidate MVRs. That the MVR of the current block is greater than the minimum MVR may indicate that a pixel unit of the MVR of the current block is greater than a pixel unit of the minimum MVR. For example, an MVR of a 1 pixel unit is greater than an MVR of a 1 / 2 pixel unit, and the MVR of a 1 / 2 pixel unit may be greater than an MVR of a 1 / 4 pixel unit. In order to adjust the default MV represented by coordinates in an interpolated image according to the minimum MVR to the MVR of the current block, the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may adjust the default MV to indicate contiguous pixels instead of a pixel indicated by the default MV. For example, in order to adjust a default MV A that indicates a pixel 3410 of the coordinates (19, 192 27) Based on the coordinates (0, 0) in FIG. 34 at an MVR of a unit of 1 pixel which is the MVR of the current block, the coordinates (19, 27) of pixel 3410 indicated by the default MV A may be divided by an integer 4 (i.e., may be scaled down), and the coordinates (19 / 4, 27 / 4) obtained as a division result may not indicate an integer unit of pixel. The motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may set the downscaled default MV to indicate an integer unit of pixel. For example, the coordinates of adjacent integer pixels around the coordinates (19 / 4, 27 / 4) are (16 / 4, 28 / 4), (16 / 4, 24 / 4), (20 / 4, 28 / 4), and (20 / 4, 24 / 4). In this case, after the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may adjust the downscaled default MV A to indicate the coordinates (20 / 4, 28 / 4) located at the upper right side instead of the coordinates (19 / 4, 27 / 4), and may multiply an integer 4 (i.e., upscale) so that a finally adjusted default MV D indicates a pixel 3440 corresponding to the coordinates (20, 28). According to one embodiment, the apparatus IVIA / a / ZUzí J / UII ooo 193 motion vector coding apparatus 2700 and motion vector decoding apparatus 2500 may set the downscaled default MV to indicate coordinates located on the left background side, coordinates located on the top left side, or coordinates located on the right background side. According to one embodiment, when any one of an x-coordinate value and a y-coordinate value indicated by the scaled-down default MV indicates an integer pixel, the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may increment or decrement only the coordinate value not indicating the integer pixel to indicate an integer pixel. That is, when the x-coordinate value indicated by the scaled-down default MV indicates an integer pixel, the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may cause the adjusted default MV to indicate an integer pixel located on top or bottom of the pixel indicated by the default MV before adjustment.Alternatively, when the y-coordinate value indicated by the downscaled default MV indicates an integer pixel, the motion vector coding apparatus 2700 and the iviA / a / zuzo / uii decoding apparatus ooo. 194 of 2500 motion vectors may cause the adjusted default MV to indicate an integer pixel located on the left or right side of the pixel indicated by the default MV before adjustment. When the default MV is set, the motion vector encoding apparatus 2700 and the motion vector decoding apparatus 2500 may differently select a point indicated by the set default MV according to the MVR of the current block. For example, with reference to FIG. 35, when the MVR of the current block is an MVR of a unit of 1 / 2 pixel, the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may cause the adjusted default MV to indicate a pixel 3530 at the upper left side of a pixel indicated by the default MV before adjustment; when the MVR of the current block is an MVR of a unit of 1 pixel, the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may cause the adjusted default MV to indicate a pixel 3520 at the upper right side of the pixel indicated by the default MV before adjustment; and when the MVR of the current block is an MVR of a unit of 2 pixels, the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may cause the adjusted default MV to indicate a pixel 3520 at the upper right side of the pixel indicated by the default MV before adjustment; IVIA / a / ZUzí J / UII ooo 195 motion 2700 and motion vector decoding apparatus 2500 may cause the adjusted default MV to indicate a pixel 3540 on the right background side of the pixel indicated by the default MV before adjustment. When the default MV is adjusted in view of the MVR of the current block and the minimum MVR, the motion vector encoding apparatus 2700 and the motion vector decoding apparatus 2500 may adjust the default MV according to Equation 1 below. Equation 1 MV' default = ((MV default >> k) + offset) << k In Equation 1, MV' default indicates the adjusted default MV and k is a value determined according to a difference between the MVR of the current block and the minimum MVR, where k can be mn when the MVR of the current block is in unit of 2 mpixels (m is an integer), the minimum MVR is in unit of 2 npixels (n is an integer), and m > n. According to one embodiment, k may be an index of an MVR, and when the candidate MVRs include an MVR of a 1 / 4 pixel unit, an MVR of a 1 / 2 pixel unit, an MVR of a 1 pixel unit, an MVR of a 2 pixel unit, and an MVR of a 4 pixel unit, the MVRs corresponding to indexes are as shown in Table 2. iviA / a / zuzo / uii ooo 196 When an MVR index is received from a bit stream, the motion vector decoding apparatus 2500 may set the default MV according to Equation 1 by using the MVR index as k. Also, in Equation 1, "" or "<<" which is a bit offset operation refers to an operation to reduce or increase a size of a default MV. Also, offset indicates a value added or subtracted to indicate an integer pixel when the default MV scaled according to a k value does not indicate an integer pixel, the offset may be determined differently according to each of an x-coordinate value and a y-coordinate value of the default MV. According to one embodiment, when the downscaled default MV is changed to indicate an integer pixel, the motion vector encoding apparatus 2700 and the motion vector decoding apparatus 2500 may change the downscaled default MV according to the same criterion. According to one embodiment, when an x-coordinate value and a y-coordinate value of the downscaled default MV do not indicate an integer pixel, the motion vector encoding apparatus 2700 and the motion vector decoding apparatus 2500 197 may always increment or decrement the x-coordinate value and the y-coordinate value of the downscaled default MV to indicate an integer pixel. Alternatively, the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may round the x-coordinate value and the y-coordinate value of the downscaled default MV to indicate an integer pixel. According to one embodiment, when the default MV is set, the motion vector coding apparatus 2700 and the motion vector decoding apparatus 2500 may skip scaling down and upscaling the default MV, and may adjust the default MV on a coordinate plane in an interpolated reference image according to the minimum MVR to indicate a pixel unit corresponding to the MVR of the current block. Also, according to one embodiment, when the default MV is adjusted in view of the MVR of the current block and the minimum MVR, the motion vector encoding apparatus 2700 and the motion vector decoding apparatus 2500 may adjust the default MV according to Equation 2 below, instead of Equation 1. Equation 2 MV' default = ( (MV default + offset) IVIA / a / ZUzí J / UII ooo 198 » k) « k Although Equation 2 is similar to Equation 1, unlike in Equation 1 where compensation is applied to the downscaled default MV, compensation is applied to the original default MV and then downscaled according to k. The motion vector coding apparatus 2700 finds an MV of the current block by using the MVR of the current block, and obtains a difference between the MV and the PMV of the current block as a residual MV. The motion vector encoding apparatus 2700 may determine and encode the residual MV as shown in Equation 3 below. In Equation 3, MV indicates the motion vector of the current block, PMV indicates the PMV, and MVD indicates the residual MV. PMV may indicate the PMV determined based on the adjusted default MV and / or an adjusted MV of the PMV candidate block. Equation 3 MVD = MV-PMV When the MVR of the current block is higher than the minimum MVR, the motion vector coding apparatus 2700 may downscale the residual MV as shown in Equation 4, and may generate a bit stream including information indicating the residual MV. QQQI scaled down. 199 Equation 4 MVD' = (MVD » k) In Equation 4, MVD' indicates the downscaled residual MV, and k which is a value determined according to a difference between the minimum MVR and the MVR of the current block is the same as k in Equation 1. According to one embodiment, the motion vector coding apparatus 2700 may downscale the MV and the PMV of the current block according to the value k, and then may encode a difference between the two values ​​as the residual MV. According to one embodiment, the motion vector coding apparatus 2700 may calculate the downscaled residual MV according to Equation 5 below, instead of Equation 3 and Equation 4. Equation 5 MVD' = (MV - PMV) / (R * S) In Equation 5, MVD' denotes the downscaled residual MV, MV denotes the MV of the current block, and PMV denotes the PMV. Also, R denotes a pixel unit value of the MVR of the current block (e.g., 1 / 4 when the MVR of the current block is an MVR of 1 / 4 pixel unit). Also, S denotes a reciprocal of a pixel unit value of the minimum MVR (e.g., 4 when the minimum MVR is 1 / 4 pixel unit). iviA / a / zuzo / uii ooo 200 The motion vector decoding apparatus 2500 may reconstruct the MV of the current block by using the PMV of the current block and the residual MV. When the MVR of the current block is higher than the minimum MVR, the motion vector decoding apparatus 2500 may upscale the residual motion data as shown in Equation 6 below. Equation 6 MVD'' = (MVD' « k) In Equation 6, MVD' indicates the residual MV downscaled by an encoding apparatus, and MVD indicates a residual MV upscaled, k which is a value determined according to a difference between the minimum MVR and the MVR of the current block is the same as k in Equation 1. The motion vector decoding apparatus 2500 may decode the MV of the current block by adding the residual MV that is selectively upscaled according to the difference between the minimum MVR and the MVR of the current block to the PMV. According to one embodiment, the motion vector decoding apparatus 2500 may determine the upscaled residual MV according to Equation 7 below, instead of Equation 6 above. 201 Equation 7 MVD = MVD' * (R * S) In equation 7, MVD' denotes the downscaled residual MV, and R denotes a pixel unit value of the MVR of the current block (e.g., 1 / 4 when the MVR of the current block is an MVR of 1 / 4 pixel unit). Also, S denotes a reciprocal of a pixel unit value of the minimum MVR (e.g., 4 when the minimum MVR is 1 / 4 pixel unit). According to one embodiment, when the MVR of the current block is less than an MVR of a 1-pixel unit, the motion vector decoding apparatus 2500 may interpolate the reference image according to the minimum MVR and then search for a prediction block of the current block according to the MV of the current block. Also, when the MVR of the current block is equal to or higher than an MVR of a 1-pixel unit, the motion vector decoding apparatus 2500 may search for the prediction block of the current block according to the MV of the current block without interpolating the reference image. The motion vector decoding apparatus 2500 may reconstruct the current block by adding the prediction block to inversely transformed and inversely quantized residual data. The modalities can be implemented as a 202 computer executable program, and the program can be stored on a medium. The medium may continuously store the computer-executable program, or it may temporarily store the computer-executable program to execute or download the computer-executable program. Also, the medium may be any of several recording media or storage media, including individual hardware (physical components) or a combination of multiple hardware components, and may be distributed over a network without being limited to a medium directly connected to a computer system.The medium may be configured to store program instructions, and examples of the medium may include a magnetic medium such as a hard disk, a floppy disk, or a magnetic tape, an optical recording medium such as a compact disc read-only memory (CD-ROM) or a digital versatile disc (DVD), a magneto-optical medium such as a floppy disk, a ROM, a random access memory (RAM), and non-volatile memory. Also, other examples of the medium may include a recording medium and a storage medium managed by an application store that distributes applications or a site or server that provides or distributes various other software (items). 203 programming). While the disclosure has been particularly shown and described with reference to embodiments thereof, one of ordinary skill in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope of the disclosure as defined by the appended claims. It is noted that in relation to this date, the best method known to the applicant to put the aforementioned invention into practice is the one that is clear from the present description of the invention.

Claims

1. A method for decoding a motion vector, the method comprising: obtaining, from a bit stream, information regarding a residual motion vector, and information indicating a particular motion vector resolution of a current block from a plurality of motion vector resolutions including a first motion vector resolution; when a motion vector of a first candidate block corresponding to the first motion vector resolution indicated by the information indicating the particular motion vector resolution is available, determining the motion vector of the first candidate block as a prediction motion vector of the current block, wherein a position of the first candidate block is determined based on the information indicating the particular motion vector resolution;when the motion vector of the first candidate block is not available, determining a default motion vector from default motion vector candidates 205 according to a priority, and determining the default motion vector as the prediction motion vector of the current block; adjusting the prediction motion vector by applying a compensation operation based on information indicating the particular motion vector resolution to the prediction motion vector; scaling the residual motion vector using the information indicating the particular motion vector resolution; and obtaining a motion vector of the current block by using the scaled residual motion vector and the adjusted prediction motion vector of the current block.

2. A method for encoding a motion vector, the method comprising: selecting a particular motion vector resolution of a current block from a plurality of motion vector resolutions including a first motion vector resolution; when a motion vector of a first candidate block corresponding to the first motion vector resolution selected as the particular motion vector resolution of the current block is available, determining the motion vector of the first candidate block as a prediction motion vector of the current block; when the motion vector of the first candidate block is not available, determining a default motion vector from default motion vector candidates according to a priority, and determining the default motion vector as the prediction motion vector of the current block;adjusting the prediction motion vector by applying a compensation operation based on information indicating the particular motion vector resolution of the current block to the prediction motion vector; obtaining a residual motion vector using a motion vector of the current block and the adjusted prediction motion vector of the current block; and scaling the residual motion vector using the information indicating the particular motion vector resolution; and generating a bit stream comprising the information indicating the particular motion vector resolution and information regarding the scaled residual motion vector, wherein a position of the first candidate block is determined based on the information indicating the particular motion vector resolution. IVIA / a / ZUzí J / UII ooo 207; 3. An apparatus for decoding a motion vector, the apparatus comprising: an acquirer configured to obtain, from a bit stream, information regarding a residual motion vector, and information indicating a particular motion vector resolution of a current block from a plurality of motion vector resolutions including a first motion vector resolution; and a decoder configured to: when a motion vector of a first candidate block corresponding to the first motion vector resolution indicated by the information indicating the particular motion vector resolution is available, determine the motion vector of the first candidate block as a prediction motion vector of the current block, wherein a position of the first candidate block is determined based on the information indicating the particular motion vector resolution;when the motion vector of the first candidate block is not available, determining a default motion vector from default motion vector candidates according to a priority, and determining the default motion vector as the prediction motion vector of the current block; adjusting the prediction motion vector by applying a compensation operation based on information indicating the particular motion vector resolution to the prediction motion vector; scaling the residual motion vector using the information indicating the particular motion vector resolution; and obtaining a motion vector of the current block by using the scaled residual motion vector and the adjusted prediction motion vector of the current block.

4. An apparatus for encoding a motion vector, the apparatus comprising: an encoder configured to: select a particular motion vector resolution of a current block from a plurality of motion vector resolutions including a first motion vector resolution; when a motion vector of a first candidate block corresponding to the selected first motion vector resolution as the particular motion vector resolution of the current block is available, determining the motion vector of the first candidate block as a prediction motion vector of the current block;when the motion vector of the first candidate block 209 is not available, determining a default motion vector from default motion vector candidates according to a priority, and determining the default motion vector as the prediction motion vector of the current block; adjusting the prediction motion vector by applying a compensation operation based on information indicating the particular motion vector resolution of the current block to the prediction motion vector; obtaining a residual motion vector using a motion vector of the current block and the adjusted prediction motion vector of the current block;and scaling the residual motion vector using the information indicating the particular motion vector resolution, and a generator configured to generate a bit stream comprising the information indicating the particular motion vector resolution of the current block and information regarding the scaled residual motion vector, wherein a position of the first candidate block is determined based on the information indicating the particular motion vector resolution.; 5. A non-transitory machine-readable medium for recording a bit stream, characterized in that the bit stream comprises: information indicating a particular motion vector resolution of a current block among a plurality of motion vector resolutions including a first motion vector resolution; and information related to a scaled residual motion vector, wherein the scaled residual motion vector is obtained by: when a motion vector of a first candidate block corresponding to the first motion vector resolution selected as the particular motion vector resolution of the current block is available, determining the motion vector of the first candidate block as a prediction motion vector of the current block;when the motion vector of the first candidate block is not available, determining a default motion vector from default motion vector candidates according to a priority, and determining the default motion vector as the prediction motion vector of the current block; adjusting the prediction motion vector by applying a compensation operation based on information indicating the particular motion vector resolution to the prediction motion vector; obtaining the residual motion vector using a motion vector of the current block and the adjusted prediction motion vector of the current block; and scaling the residual motion vector using the information indicating the particular motion vector resolution, wherein a position of the first candidate block is determined based on the information indicating the particular motion vector resolution.

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