WO2019135447A1

WO2019135447A1 - Video encoding method and device and video decoding method and device, using padding technique based on motion prediction

Info

Publication number: WO2019135447A1
Application number: PCT/KR2018/003803
Authority: WO
Inventors: 박민수; 최웅일; 김찬열
Original assignee: 삼성전자 주식회사
Priority date: 2018-01-02
Filing date: 2018-03-30
Publication date: 2019-07-11
Also published as: WO2019135457A1; KR20200096551A

Abstract

The video decoding method according to one embodiment of the present disclosure comprises the steps of: obtaining prediction information of blocks adjacent to the inside of an outline of a reference image, if a current block refers to a region outside an outer boundary of the reference image during motion reference; determining reference samples for predicting samples positioned outside the outline, by using prediction information of a block adjacent to the inside of the outline; and determining samples positioned outside the outline of the reference image by using the reference samples.

Description

Video encoding method and apparatus using padding scheme by motion prediction, video decoding method and apparatus

For motion prediction of the current image, the image can be encoded or decoded using peripheral information of the reference image.

Since a video includes a large amount of data, video encoding / decoding methods and apparatuses for dividing each video included in the video into a plurality of blocks and encoding them are used.

Also, an inter prediction method for predicting a current image using a previous image or a next image is used during a video encoding / decoding process on the assumption that the content of the current image is similar to the previous or next image of the current image. Inter prediction can also be performed for each block. For inter prediction for the current block among the blocks of the current image, the distance between the current block and the closest block among the blocks of other images can be expressed mainly as a motion vector. It is possible to predict the sample values of the current block by using the motion vector determined by the inter prediction. Specifically, among the blocks of another image (reference image), sample values of a current block can be predicted using a sample value of a block (reference block) that is separated from a current block by a motion vector.

According to an aspect of the present invention, there is provided a video encoding method comprising: obtaining prediction information of blocks adjacent to an inside of an outline of a reference image when a current block refers to an out-of-bounds region of the reference image in motion reference; Determining reference samples for predicting samples located outside the outline of the reference image using prediction information of a block adjacent to the outline; And determining the samples located outside the outline of the reference image using the reference samples.

The reference samples may be located in an image.

The prediction information is inter-prediction information of a block adjacent to the outline, and the inter-prediction information may include at least one of a reference picture list, a reference index, and a motion vector.

Wherein when the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the areas of the areas indicated by the motion vectors of the L1 reference list, The predictive information corresponding to the motion vector of the L0 reference list and the predictive information corresponding to the motion vector of the L1 reference list are used for a region of a smaller size among the neighboring regions, the reference samples can be determined in a linear manner.

When the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the motion vector of the L1 reference list are shifted in the outward direction of the area indicated by the first motion vector The reference samples may be determined using the prediction information excluding the prediction information corresponding to the first motion vector when the neighboring region is outside the image.

When the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the motion vector of the L1 reference list are shifted in the outward direction of the area indicated by the first motion vector When the neighboring region is outside the image, the reference samples can be generated using the samples adjacent to the inside of the outline of the reference image.

The prediction information may be intra mode information of a block adjacent to the inside of the outline, and the reference samples may be determined from samples in the reference image according to the intra mode information.

The prediction information is information on a characteristic of a block adjacent to the outline, and the reference samples may be determined according to information on the characteristic.

When the block adjacent to the outline is generated through the affine mode, the prediction information may include affine mode information, and the reference samples may be determined according to the affine mode information.

The characteristics of the block adjacent to the inside of the outline may be determined using one of a gradient and an edge detection. In this case, the prediction information may include a characteristic of a block adjacent to the inside of the outline Information.

A block related to a block adjacent to the contour line may be determined by a template matching method, and the prediction information may include prediction information of the related block.

When the reference image is one of a plurality of images combined according to a 360-degree image format, if prediction information of a block adjacent to an inside of an outline of the reference image exists, It is possible to generate sample values of an area outside the outline.

The 360 degree image may be generated by one of Rotated Sphere Projection (RSP), Equirectangular Projection (ERP), Icosahedral Projection (ISP), Segmented Sphere Projection (SSP), CubeMap Projection (CMP), Equal Area Cube Map .

According to an aspect of the present invention, there is provided a video decoding method comprising: obtaining prediction information of blocks adjacent to an inside of an outline of a reference image when a current block refers to an out-of-bounds region of the reference image in motion reference; Determining reference samples for predicting samples located outside the outline of the reference image using prediction information of a block adjacent to the outline; And determining the samples located outside the outline of the reference image using the reference samples.

According to an aspect of the present invention, there is provided a video encoding apparatus including: a prediction information obtaining unit that obtains prediction information of blocks adjacent to an inside of an outline of a reference image, when a current block refers to an out-of- A reference sample determining unit for determining reference samples for predicting samples located outside the outline of the reference image using prediction information of a block adjacent to the inside of the outline; And an outer sample determination unit for determining a sample located outside the outline of the reference image using the reference samples.

According to an aspect of the present invention, there is provided a video decoding apparatus comprising: a prediction information obtaining unit that obtains prediction information of blocks adjacent to an inside of an outline of a reference image, when a current block refers to an out-of- A reference sample determining unit for determining reference samples for predicting samples located outside the outline of the reference image using prediction information of a block adjacent to the inside of the outline; And an outer sample determination unit for determining a sample located outside the outline of the reference image using the reference samples.

FIG. 1A shows a flowchart of a padding method of an image outside region using prediction information according to an exemplary embodiment.

FIG. 1B is a flowchart illustrating a method of predicting a motion of an outer region of a reference image using prediction information according to another embodiment.

FIG. 2A illustrates a block diagram of an image padding apparatus using prediction information according to an embodiment.

FIG. 2B is a block diagram of a motion prediction apparatus to which a padding method of a reference image outer region using prediction information is applied according to another embodiment.

FIG. 3 illustrates a method of padding an outer region of a reference image according to a conventional padding method.

4A illustrates a method of padding an outer region of a reference image using inter information according to an embodiment.

4B illustrates a method of padding an outer region of a reference image using intra information according to an exemplary embodiment of the present invention.

FIG. 5 shows an example of a reference image to which a conventional padding method is applied.

6 illustrates an example of a reference image to which the padding method according to an embodiment is applied.

FIG. 7 shows an example of a 360-degree image to which the conventional padding method is applied.

FIG. 8 illustrates an example of a reference image of a 360-degree image to which a padding method of a reference image outside region according to an embodiment is applied.

FIG. 9 illustrates an example of a reference image of a 360-degree image to which a padding method of a reference image outside area is applied according to another embodiment.

10A is a block diagram of a video encoding apparatus to which a padding method of a reference image outside region using prediction information according to an embodiment is applied.

FIG. 10B is a block diagram of a video decoding apparatus to which a padding method of a reference image outside region using prediction information according to an embodiment is applied.

FIG. 11 illustrates a process in which an image decoding apparatus determines at least one encoding unit by dividing a current encoding unit according to an embodiment.

FIG. 12 illustrates a process in which an image decoding apparatus determines at least one encoding unit by dividing a non-square encoding unit according to an embodiment.

FIG. 13 illustrates a process in which an image decoding apparatus divides an encoding unit based on at least one of information on a block format information and a format mode according to an embodiment.

FIG. 14 illustrates a method for an image decoding apparatus to determine a predetermined encoding unit among odd number of encoding units according to an embodiment.

FIG. 15 illustrates a sequence in which a plurality of coding units are processed when an image decoding apparatus determines a plurality of coding units by dividing a current coding unit according to an embodiment.

16 illustrates a process of determining that the current encoding unit is divided into odd number of encoding units when the image decoding apparatus can not process the encoding units in a predetermined order according to an embodiment.

FIG. 17 illustrates a process in which an image decoding apparatus determines at least one encoding unit by dividing a first encoding unit according to an embodiment.

FIG. 18 is a diagram illustrating an example in which when the non-square second encoding unit determined by dividing the first encoding unit by the image decoding apparatus satisfies a predetermined condition, a form in which the second encoding unit can be divided is limited Lt; / RTI >

FIG. 19 illustrates a process in which an image decoding apparatus divides a square-shaped encoding unit when the information on the split mode mode can not be divided into four square-shaped encoding units according to an exemplary embodiment.

FIG. 20 illustrates that a processing order among a plurality of coding units may be changed according to a division process of coding units according to an embodiment.

FIG. 21 illustrates a process in which the depth of an encoding unit is determined according to a change in type and size of an encoding unit when a plurality of encoding units are determined by recursively dividing an encoding unit according to an exemplary embodiment.

FIG. 22 illustrates a depth index (hereinafter referred to as a PID) for classifying a depth and a coding unit that can be determined according to the type and size of coding units according to an exemplary embodiment.

23 illustrates that a plurality of coding units are determined according to a plurality of predetermined data units included in a picture according to an embodiment.

FIG. 24 shows a processing block serving as a reference for determining a determination order of reference encoding units included in a picture according to an embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the disclosed embodiments, and how to accomplish them, will become apparent with reference to the embodiments described below with reference to the accompanying drawings. It should be understood, however, that the present disclosure is not limited to the embodiments disclosed herein but may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, It is only provided to give the complete scope of the invention to the person.

The terms used in this specification will be briefly described, and the disclosed embodiments will be described in detail.

As used herein, terms used in the present specification are taken to be those of ordinary skill in the art and are not intended to limit the scope of the present invention. Also, in certain cases, there may be a term selected arbitrarily by the applicant, in which case the meaning thereof will be described in detail in the description of the corresponding invention. Accordingly, the terms used in this disclosure should be defined based on the meaning of the term rather than on the name of the term, and throughout the present disclosure.

The singular expressions herein include plural referents unless the context clearly dictates otherwise.

When an element is referred to as "including" an element throughout the specification, it is to be understood that the element may include other elements as well, without departing from the spirit or scope of the present invention.

In addition, the term "part" used in the specification means software or hardware component, and "part " However, "part" is not meant to be limited to software or hardware. "Part" may be configured to reside on an addressable storage medium and may be configured to play back one or more processors. Thus, by way of example, and not limitation, "part (s) " refers to components such as software components, object oriented software components, class components and task components, and processes, Subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays and variables. The functions provided in the components and "parts " may be combined into a smaller number of components and" parts " or further separated into additional components and "parts ".

In accordance with one embodiment of the present disclosure, "part" may be embodied in a processor and memory. The term "processor" should be broadly interpreted to include a general purpose processor, a central processing unit (CPU), a microprocessor, a digital signal processor (DSP), a controller, a microcontroller, a state machine, In some circumstances, a "processor" may refer to an application specific integrated circuit (ASIC), a programmable logic device (PLD), a field programmable gate array (FPGA) The term "processor" refers to a combination of processing devices, such as, for example, a combination of a DSP and a microprocessor, a combination of a plurality of microprocessors, a combination of one or more microprocessors in conjunction with a DSP core, It can also be called.

The term "memory" should be broadly interpreted to include any electronic component capable of storing electronic information. The terminology memory may be any suitable memory such as random access memory (RAM), read-only memory (ROM), non-volatile random access memory (NVRAM), programmable read-only memory (PROM), erase- May refer to various types of processor-readable media such as erasable programmable read-only memory (PROM), flash memory, magnetic or optical data storage devices, registers, and the like. A memory is said to be in electronic communication with a processor if the processor can read information from and / or write information to the memory. The memory integrated in the processor is in electronic communication with the processor.

Hereinafter, the "image" may be a static image such as a still image of a video or a dynamic image such as a moving image, i.e., the video itself.

Hereinafter, "sample" means data to be processed as data assigned to a sampling position of an image. For example, pixel values in the image of the spatial domain, and transform coefficients on the transform domain may be samples. A unit including at least one of these samples may be defined as a block.

Hereinafter, the "padding" operation refers to an operation of copying a sample value of another pixel to generate a sample value of the current pixel.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. In order to clearly explain the present disclosure in the drawings, portions not related to the description will be omitted.

Hereinafter, a motion prediction method and apparatus, a video encoding method and apparatus, a video decoding method and an apparatus to which a method of padding a reference image outside region according to an embodiment will be described in detail with reference to FIGS. 1A to 10B. 11 to 24, a method of determining a data unit of an image according to an embodiment will be described.

Hereinafter, the current block means the block of the current image, and the reference block means the block indicated by the motion vector of the current image in the reference image of the current image.

Referring to FIG. 1A, according to a padding method of an image outside area according to an embodiment of the present disclosure, in step s10, prediction information of a current block adjacent to an outline of a current image is obtained.

In general, when a pixel location points outside the image outline, a sample value for that pixel location is defined as " unavailable " because it does not exist. An image padding method according to the present disclosure attempts to predict a sample value of an outer region located outside an outline of a current image using prediction information of a current block when prediction information of a current block exists.

The reference samples for predicting the samples located outside the outline of the current block can be determined using the prediction information of the current block in step s12. Reference samples may be located within the current or reference image. In step s14, the samples located outside the outline of the current image, which are adjacent to the current block using the reference samples determined in step s12, may be determined. As a result, the samples located in the outer region of the current image can be padded.

The prediction information of the motion prediction method to which the padding method of the reference region is applied may be intra prediction information of a neighboring block or intra mode information of a neighboring block or may be affine motion information of neighboring blocks.

The inter prediction information of a current block used for padding of an image outside area according to an exemplary embodiment may include at least one of a reference picture list, a reference index, and a motion vector. More specifically, the reference image of the current block can be determined using the inter prediction information. The reference image may be determined from among the images included in at least one of the reference list of the current block, i.e., the L0 list and the L1 list. The position indicated by the motion vector of the current block among the blocks of the reference image may be the position of the reference block.

The reference picture list of the inter prediction information according to an embodiment may indicate at least one of the L0 reference list and the L1 reference list.

When the L0 reference list is used, one reference image among the images included in the L0 reference list can be determined using the L0 reference index. When the L1 reference list is used, one reference image among the images included in the L1 reference list can be determined using the L1 reference index.

The image padding method according to an exemplary embodiment may use the neighboring blocks of the reference block determined according to the inter prediction information of the current block to padd the samples outside the outline of the current image. That is, the samples of the pixels included in the neighboring block of the reference block indicated by the motion vector of the current block may be determined as reference samples, and the sample values of the image outside region adjacent to the current block may be determined using the reference samples.

Specifically, if there are image outlines and outer samples adjacent to the left side of the current block, the outer samples of the current block can be determined using reference samples of neighboring blocks adjacent to the left side of the reference block of the current block.

If there are image outlines and outer samples adjacent to the upper side of the current block, the outer samples of the current block can be determined using reference samples of neighboring blocks adjacent to the upper side of the reference block of the current block.

If there are image outlines and outer samples adjacent to the right side of the current block, the outer samples of the current block can be determined using reference samples of neighboring blocks adjacent to the right side of the reference block of the current block.

If there are image contours and outer samples adjacent to the lower side of the current block, the outer samples of the current block can be determined using the reference samples of the neighboring block below the reference block of the current block.

In the case of the inter prediction according to the Bi-prediction mode in which the L0 reference list and the L1 reference list can be used, in the case where the area indicated by one of the L0 motion vector and the L1 motion vector is outside the image, The reference samples can be determined using the remaining prediction information excluding the prediction information corresponding to the motion vector. As another example, when the region indicated by one motion vector of the L0 motion vector and the L1 motion vector is outside the image, samples adjacent to the outline among the samples of the current block are determined as reference samples, The image outside area can be padded.

A method of padding an image outside area according to the inter prediction information of the current block will be described later with reference to FIG. 4A.

According to one embodiment, among the samples in the current image, reference samples for padding the outer region can be determined according to the intra mode information of the current block.

The intra mode information of the current block used for padding of the out-of-picture area according to an exemplary embodiment may be an intra prediction mode indicating a direction of neighboring samples referred to predict a sample of the current block. For example, the intra-prediction mode may include 33 directional prediction modes, a DC mode, and a planar mode. However, the present invention is not limited thereto, and the direction prediction mode of the intra prediction mode can be subdivided into 62 direction prediction modes. Also, the intra-prediction mode may include at least one of a DC mode, a vertical mode, a horizontal mode, a planar mode, a diagonal mode in an upper left and lower right direction, and a diagonal mode in an upper right and lower left direction .

Thus, from the outer samples of the outline of the current image, the samples in the current image, which are located according to the direction indicated by the intra prediction mode of the current block, can be determined as reference samples for padding the outer sample. A method of padding an image outside area according to the intra prediction mode of the current block will be described later with reference to FIG. 4B.

According to another example, the characteristics of a block adjacent to an outline may be determined using a method such as gradient, edge detect, etc. In this case, the prediction information may include information on the characteristics of the block adjacent to the outline . &Lt; / RTI >

In the process of determining a reference block for motion prediction, a method of padding an outer region of an image according to an embodiment may be applied. More specifically, a method of padding a reference block when a reference block for motion prediction is located outside the reference image will be described below with reference to FIGS. 1B and 2B.

However, in the case of in-loop filtering such as deblocking filtering, sample adaptive offset (SAO), and adaptive loop filtering (ALF), when a reference sample to be filtered is located outside the image , A conventional padding method can be used to generate reference samples values. That is, at the time of in-loop filtering, a reference sample can be generated by copying samples inside an image adjacent to a reference sample around a video outline to padding a reference sample located outside the image .

According to another embodiment of the present invention, a padding method for an image outside region can find a block related to a current block through template matching, and can perform padding using a related block.

Template matching is a method of determining a template area of a certain type surrounding a block and determining that a block surrounded by the detected area is a similar block of the block when the closest area to the template area is detected in the reference image. Accordingly, if template matching is applied to the padding method according to the present disclosure, the following procedure can be followed. If the current block is adjacent to the outline of the current image, a template of the current block in the current image may be determined, and a block surrounded by the area detected by template matching may be determined as a similar block of the current block. The sample values of the block adjacent to the pseudo block of the current block can be determined as the sample values for padding the image outside region adjacent to the current block.

FIG. 1B shows a flowchart of an applied motion prediction method of a padding method of a reference image outside region according to an embodiment.

Referring to FIG. 1B, according to a motion estimation method to which a padding method of a reference image outside area according to an embodiment of the present disclosure is applied, in step s11, a reference block for inter prediction of a current block is divided into sub- Prediction information of at least one block adjacent to the inside of the outline of the reference image is obtained. The motion vector of the current block can be determined by inter prediction of the current block. The sample value of the current block can be compensated using the sample value of the reference block, that is, the area indicated by the motion vector of the current block. In general, when the motion vector of the current block indicates an area outside the reference frame, the sample value for the position of the frame outside the reference frame does not exist. Therefore, the motion vector is 'unavailable' Is defined. The motion prediction method according to the present disclosure includes the steps of acquiring prediction information of another block adjacent to an inside of an outline of a reference image when a motion vector of the current block indicates an area outside the outline of the reference image, To estimate the sample values of the reference block located outside the outline.

The reference image may be determined from among the images included in at least one of the reference list of the current block, i.e., the L0 list and the L1 list. The position indicated by the motion vector of the current block among the blocks of the reference image may be the position of the reference block.

The positions of all the pixels included in the reference block may be located outside the outline of the reference image. Or the position of some pixels included in the reference block may be located outside the outline of the reference image.

The reference samples used for predicting the samples located outside the outline of the reference image are determined using the prediction information of the block adjacent to the inside of the outline of the reference image in step s13. In step S15, the samples located outside the outline of the reference image are determined using the determined reference samples.

Referring to FIG. 1B, a reference picture selected from a reference list of a current block is referred to as a 'current reference picture', and a reference block or a region indicated by a current block motion vector in a 'current reference picture' Reference block " and " current reference region ".

Hereinafter, an image for predicting a sample located outside the outline of the current reference image (hereinafter referred to as an "external sample") is referred to as a reference image by prediction information of a block adjacent to the inside of the outline of the current reference image it means.

The prediction information of the motion prediction method to which the padding method of the reference image outside region is applied may be determined based on the inter prediction information of the block adjacent to the inside of the outline of the current reference image or the intra prediction mode of the block adjacent to the inside of the outline of the current reference image, Information.

Specifically, in order to predict external samples of the current reference image, inter prediction information among prediction information of adjacent blocks in the outline may be used. The 'image for predicting the external samples' of the current reference image can be determined from the images included in at least one of the reference list of the 'block adjacent to the inside of the outline' of the current reference image, that is, the L0 list and the L1 list. The reference block of the 'block adjacent to the outline' can be determined based on the position indicated by the motion vector of the 'block adjacent to the outline' within the 'reference image for predicting the external samples'.

Among the pixels of the image for predicting the external samples, it is possible to predict the external samples using the samples adjacent to the reference block of the 'block adjacent to the inside of the outline'. Outer samples of the current reference image can be predicted using samples adjacent in the outline direction of the 'reference image of a block adjacent to the outline' among the samples adjacent to the reference block of the 'block adjacent to the inside of the outline' Reference samples for padding outer samples may be located within an image for predicting outer samples. On the other hand, when the reference samples are located outside the image for predicting the outer samples, the outer samples can be padded using the samples adjacent to the inside of the outline of the current reference image.

The outer samples may be samples of the pixels included in the reference block of the current block.

If the positions of all the pixels included in the reference block of the current block are located outside the outline of the current reference image, among the pixels of the image for predicting the external samples, corresponding to all the pixels included in the reference block of the current block All samples of the reference block, i.e., the outer samples, can be padded.

Or if the position of some pixels included in the reference block of the current block is located outside the outline of the current reference image, among the pixels of the image for predicting the external samples, some pixels included in the reference block of the current block Corresponding, some samples of the reference block may be padded with samples of some pixels, i.e., the outer samples.

In addition, when the block adjacent to the inside of the outline of the current reference image is generated through the affine mode, the prediction information of the block adjacent to the inside of the outline may include the affine mode information, and the affine mode information , It is possible to determine reference samples for predicting outer samples of the current reference image.

According to one embodiment, the inter prediction information of a block adjacent to the inside of the outline of the current reference image, which is used for padding of the current reference image outside region, may include at least one of a reference picture list, a reference index, and a motion vector . Specifically, an image indicated by the reference index in the reference picture list of a block adjacent to the inside of the outline of the current reference image is determined as a reference image for predicting the external samples. The position indicated by the motion vector of the block adjacent to the inside of the outline of the reference image among the reference images for predicting the external samples can be determined as a block to be a reference object. Neighboring samples of a block to be referred to can be determined as samples for predicting external samples, i.e., samples located outside the outline of the current reference image.

Specifically, if the reference block of the current block exists outside the left outline of the current reference image and there is inter prediction information of a block adjacent to the inside of the left outline, the inter prediction information of the block adjacent to the inside of the left outline The reference block in the video and image to be referred to is determined. Blocks or samples located outside the left outline of the current reference image may be predicted using neighboring blocks or samples adjacent to the left side of the reference block in the determined image.

If the reference block of the current block exists outside the upper outline of the reference image and the inter prediction information of the block adjacent to the inside of the upper outline exists, the inter prediction information of the block adjacent to the inside of the upper outline, The reference block in the image and the image is determined. Blocks or samples located outside the upper outline of the current reference image may be predicted using neighboring blocks or samples adjacent to the upper side of the reference block in the determined image.

If the reference block of the current block exists outside the right outline of the reference image and there is inter prediction information of a block adjacent to the inside of the right outline, the inter prediction information of the block adjacent to the inside of the right outline, And reference blocks in the image and the image are determined. Blocks or samples located outside the right outline of the current reference image may be predicted using neighboring blocks or samples adjacent to the right side of the reference block within the determined image.

When the reference block of the current block exists outside the lower edge of the reference image and the inter prediction information of the block adjacent to the inside of the lower edge exists, the lower side determined by the inter prediction information of the block adjacent to the inside of the lower edge, A reference block in a video and an image to be a reference of a block adjacent to the inside of the outline is determined. A block or samples located outside the lower outline of the current reference image may be predicted using neighboring blocks or samples that are adjacent to the lower side of the reference block in the determined image.

In a motion estimation method to which a padding method of an outer region of a reference image according to an embodiment is applied, a reference picture list of inter prediction information of a block adjacent to an inside of an outline of a current reference picture includes at least one of an L0 reference list and an L1 reference list Can point to.

When an L0 reference list of a block adjacent to an inside of an outline of a current reference image is used, an image indicated by the L0 reference index of a block adjacent to the inside of the outline of the current reference image among the images included in the L0 reference list is referred to The L0 image for predicting the samples located outside the outline of the image can be determined.

If the position of the block neighboring the outline of the block pointed by the L0 motion vector of the block adjacent to the inside of the outline of the current reference image is located outside the L0 image for predicting the samples located outside the outline, May be padded with sample values within the outline of the reference image.

When an L1 reference list of a block adjacent to an inside of an outline of a current reference image is used, an image indicated by an L1 reference index of a block adjacent to the inside of the outline of the current reference image among the images included in the L1 reference list, It is possible to determine the L1 image for predicting the samples located outside the outline of the reference image. If the position of the block neighboring the outline of the block indicated by the L1 motion vector of the block adjacent to the inside of the current reference image is located outside the L1 image for predicting the samples located outside the outline, Samples located outside the outline may be padded with the sample values within the outline of the current reference image.

Prediction mode according to the Bi-prediction mode available for the L0 reference list and the L1 reference list of the block adjacent to the inside of the outline of the current reference image, the reference image according to the L0 reference list of the block adjacent to the inside of the outline And the samples of the reference image according to the L1 reference list, the outer samples of the current reference image can be predicted.

The L0 reference image in the L0 reference list of the block adjacent to the inside of the current reference image is determined to be an image for predicting a sample outside the outline, and among the L0 reference images, the L0 motion vector The L0 reference block can be determined. Likewise, it is determined that the L1 reference picture of the L1 reference list of the block adjacent to the inside of the current reference picture is an image for predicting the sample outside the outline, and the L1 motion vector Lt; / RTI > reference block may be determined.

Thus, the neighboring samples of the L0 reference block in the L0 reference image of the block adjacent to the inside of the outline and the neighboring samples of the L1 reference block in the L1 reference image can be used to predict the outer samples of the current reference image. For example, using the weight based on the distance between the current reference image and the L0 reference image and the distance based on the distance between the current reference image and the L1 reference image, weights of neighboring samples of the L0 reference block and neighboring samples of the L1 reference block May be determined to be the value of the outer samples of the current reference image.

The inter prediction according to the Bi-prediction mode available for the L0 reference list and the L1 reference list of the block adjacent to the inside of the current reference image is performed and the L0 motion vector of the block adjacent in the outline of the current reference image and the L1 In the case where the area neighboring the outline of the area indicated by one motion vector of the motion vector is outside the image for predicting the samples located outside the outline, a motion indicating the outside of the image for predicting the samples located outside the outline It is possible to determine reference samples for padding samples located outside the outline of the current reference image using the prediction information other than the prediction information corresponding to the vector.

Another example is a case where an area neighboring the outline of the area indicated by the L0 motion vector and the L1 motion vector of the block adjacent to the inside of the current reference image is located outside the image for predicting the samples located outside the outline It is possible to padd samples located outside the outline of the reference image using the samples touched inside the outline of the current reference image.

As another example, when the area of the reference samples of the image for predicting the area outside the outline of the current reference image is smaller than the area to be padded outside the outline of the current reference image, External samples can be determined and padded with samples in the outward outline of the region of the reference samples for the remaining region.

In another example, inter prediction according to the Bi-prediction mode available for the L0 reference list and the L1 reference list of the block adjacent to the current reference image is performed, and L0 In the case where neighboring areas outside the outline of the areas indicated by the motion vectors and the L1 motion vectors are the inside of the L0 reference image and the L1 reference image, respectively, the reference image of the motion vector indicating the smaller one of the two neighboring areas The reference image is determined as an image for predicting samples located outside the outline of the reference image, and neighboring samples of the L0 reference block in the determined image and neighboring samples of the L1 reference block in the L1 reference image are used, Samples can be predicted.

A method of padding the outline area of the current reference image according to the inter information of the block adjacent to the inside of the outline of the current reference image will be described with reference to FIG.

A reference sample for padding an outer area of an outline of a reference image may be determined from a block in a reference image according to intra mode information of a motion estimation method to which a padding method of a reference image outer area according to an embodiment is applied.

The intra mode information of a block adjacent to an inside of an outline of a current reference image used for padding of a reference image outside region according to an embodiment of the present invention may be predicted by predicting a sample of a block adjacent to an inside of an outline of a current reference image, Prediction mode indicating the direction of neighboring samples to be referred to in order to determine the direction of neighboring samples.

According to another example, the characteristics of the block adjacent to the inside of the outline of the current reference image may be determined using a method such as gradient, edge detection, etc. In this case, Prediction information of the blocks adjacent to each other may include information on the characteristics of blocks adjacent to the outline.

A method of padding a reference block according to intra information of a block adjacent to an inside of an outline of a current reference image will be described with reference to FIG. 4B.

According to another embodiment of the present invention, a motion estimation method to which a padding method of an outer region of a reference image is applied is to find a block related to a block adjacent to an inside of an outline of a current reference image through a template matching method, Padding can be performed by using.

If template matching is applied to the padding method of the reference image outside region according to the present disclosure, the following procedure can be followed. When the reference block of the current block is out of the reference image, the template of the boundary block within the reference image adjacent to the reference block is determined, and the block surrounded by the area detected by the template matching is determined as the similar block of the boundary block . The reference block of the current block can be padded using the sample values of the block adjacent to the pseudo block of the boundary block.

Referring to FIG. 2A, an image padding apparatus 20 using prediction information according to an exemplary embodiment includes a prediction information obtaining unit 22, a reference sample determining unit 24, and an external sample determining unit 26.

The image padding apparatus 20 using prediction information according to an embodiment includes a central processor (not shown) for controlling the prediction information obtaining unit 22, the reference sample determining unit 24, and the external sample determining unit 26 can do. Alternatively, the prediction information obtaining section 22, the reference sample determining section 24 and the external sample determining section 26 are operated by respective ones of the processors (not shown), and the processors (not shown) The motion prediction apparatus to which the padding method of the reference region is applied can be operated as a whole.

The prediction information obtaining unit 22 of the image padding apparatus 20 using the prediction information according to an embodiment can obtain the prediction information of the current block adjacent to the outline of the current image. The reference sample determining unit 24 can use the prediction information of the current block to determine reference samples for predicting samples located outside the outline of the current block. The outer sample determination unit 26 may determine samples located outside the outline of the current image adjacent to the current block using the reference samples.

If the pixel of the current block in the current image is adjacent to the outline of the current image and a sample value of the pixel position of the outline region is necessary, the prediction information obtaining section 22 determines that the prediction information of the current block exists, Whether the pixel position is located in one of the upper left, upper right, lower left, and right lower sides of the current picture. If the prediction information of the current block exists and the pixel position of the outer region is not a position adjacent to one of the upper left side corner, the upper right side corner, the lower left side corner, and the lower right side corner of the current picture, the reference sample determination unit 24 It can be confirmed whether there is a neighboring sample of the reference block indicated by the prediction information of the current block. If the inter prediction information of the current block is used, it can be confirmed whether neighbor samples neighboring the reference block among the reference images of the current block exist. If intraprediction information of the current block is used, it can be confirmed whether there is a neighboring sample located in a direction according to the intra prediction mode of the current block from the pixel position of the outer region, among the samples adjacent to the inside of the outline of the current image.

If there is a neighboring sample of the reference block according to the prediction information of the current block, the sample value of the current area can be determined using the neighboring sample.

However, if there is no neighboring sample of the reference block according to the predictive information of the current block, the sample value of the current image may be determined using the sample in the outline of the current image adjacent to the outer region in the horizontal or vertical direction .

Even if the prediction information of the current block does not exist, the sample value of the current image can be determined using the sample in the outline of the current image adjacent to the outside region in the horizontal or vertical direction.

The pixel positions of the outer region are adjacent to the left upper corner of the current picture in the upper left diagonal direction, the upper right corner is adjacent to the upper right corner in the right upper diagonal direction, the lower left corner is adjacent in the lower left diagonal direction, The sample value of the current image can be determined using the sample in the outline of the current image which is adjacent to the outside region in the horizontal or vertical direction.

The method of padding the outer region of the image using the prediction information of the current block corresponds to the above description with reference to FIG. 1A, and thus a duplicated description will be omitted.

FIG. 2B is a block diagram of a motion prediction apparatus 21 to which a padding method of a reference image outside region using prediction information is applied according to an embodiment.

Referring to FIG. 2B, the motion prediction apparatus 21 to which the reference region padding method according to an embodiment is applied includes a prediction information obtaining unit 23, a reference sample determining unit 25, and an external sample determining unit 27 .

The motion prediction apparatus 21 to which the padding method of the reference region according to the embodiment is applied includes a central processor (not shown) for controlling the prediction information obtaining unit 23, the reference sample determining unit 25 and the outer sample determining unit 27 Time). Alternatively, the prediction information obtaining section 23, the reference sample determining section 25, and the external sample determining section 27 are operated by respective ones of the processors (not shown), and the processors (not shown) Accordingly, the motion prediction apparatus to which the padding method of the outer region of the reference image is applied can be operated as a whole.

The prediction information obtaining unit 23 of the motion prediction apparatus to which the padding method of the reference region according to an embodiment applies the current reference is referred to as a current reference when the motion vector determined by the inter prediction of the current block indicates an area outside the current reference image Prediction information of neighboring blocks within the outline of the image can be obtained. The reference sample determining unit 25 can determine reference samples for predicting samples located outside the outline by using prediction information of a block adjacent to the inside of the outline of the current reference image. The outer sample determination unit 27 may determine a sample located outside the outline of the current reference image using the determined reference samples for predicting the samples located outside the current reference image.

A method of determining reference samples for padding an outer region of a current reference image using prediction information of a block adjacent to an inside of an outline of a current reference image is as follows. Referring to FIG. 1B, Method, and thus redundant description will be omitted.

In a video encoding system and a video decoding system, a reconstructed image generated by decoding a current image can be used as a reference image for motion prediction of another image. The video coding system and the video decoding system may pre-padd the outer area of the restored image of the current image to generate a padding larger than the current image, A padded picture can be generated.

The image padding apparatus 20 and the motion prediction apparatus 21 according to the embodiment may be configured to classify the outer region of the decoded reconstructed image into reference samples determined using intra prediction information or intra prediction information in the reconstructed image By padding, an image larger than the original size of the restored image can be stored in the memory.

Alternatively, the image padding device 20 and the motion prediction device 21 may store the decoded original size reconstructed image first in the memory, and determine that the reference block for motion prediction of the other image exists in the outer region of the reconstructed image It is possible to generate the sample values of the reference block by padding the outer region with the reference samples determined using the intra prediction information or the intra prediction information in the reconstructed image.

Hereinafter, referring to Figs. 3 to 9, specific embodiments for padding the outer region of the reference image will be described in detail.

3, the conventional padding method is a method of padding samples 33 located outside the reference image contour 31, by using an outline line contiguous to the image contour line 31 among the pixels of the contour block 35 And copies the sample values of the pixels to generate sample values of the samples 33 located outside the reference image contour 31. [ Or outside the reference image contour line 31 through the mirroring method of using outline pixels arranged in the padding direction 37 among the pixels in the outline pixels and copying in the direction symmetrical about the contour line 31 And also generates the sample values of the samples 33.

According to one embodiment, the predicted motion may be used to pad the sample values of the outer pixels 43 that are located outside the outline of the reference image 40. The sample values of the external pixels 43 can be predicted using the inter-information of the outline block 45 adjacent to the inside of the outline of the reference image 40 adjacent to the external pixels 43. [

Specifically, the block 41 to be a reference of the outline block 45 can be determined using the reference list, the reference index, and the motion vector of the outline block 45. More specifically, in the reference list of the outline block 45, the image indicated by the reference index becomes the reference image 42 of the outline block 45, and the motion vector of the outline block 45 of the reference image 42 The block 41 to be referred to can be determined.

The samples of the neighboring block 49 adjacent to the reference block 41 may be determined as reference samples for padding the outer pixels 43 of the reference image 40. [ Therefore, the sample values of the outer pixels 43 of the reference image 40 can be replaced by the sample values of the neighboring block 49 adjacent to the block 41 to be referred to.

Referring to FIG. 4B, in the method of padding the reference image outside region according to an embodiment, in order to padding the outer pixels 43 located outside the outline of the reference image 40, The intra prediction mode 44 of the block 45 to be used.

Specifically, the intra prediction mode 44 may indicate that neighboring sample values located in the lower-right direction 48 may be used to predict a sample of a block 45 that is contiguous within the outline of the reference image. (45, 48) adjacent to the inside of the outline of the reference image (40) according to the direction indicated by the intra prediction mode (44) of the block (45) adjacent to the inside of the outline of the reference image. The external pixels 43 of the image 40 may be padded. The sample values of the pixels positioned in the lower right direction of the outer pixels 43 of the reference image 40 among the pixels adjacent to the reference image outline in the outline blocks 45 and 48 are detected by the reference image 40, The sample values of the external pixels 43 of the pixel P may be determined.

5, the conventional padding method is a method in which sample values of pixels of a reference image outside area 55 outside the outline 53 of a reference image 51 are sampled by the inner pixels 53 adjacent to the outline 53 of the reference image, The reference image outside area 55 is copied. That is, the sample values of the reference image outside region 55 adjacent to the vertical outline of the outline 53 copy the sample values of the internal pixels of the reference image 51 adjacent to the vertical outline in the horizontal direction in the horizontal direction. Similarly, the sample values of the reference image outside region 55 adjacent to the horizontal outline of the outline 53 copy the sample values of the internal pixels of the reference image 51 adjacent to the horizontal outline in the vertical direction in the vertical direction.

Referring to FIG. 6, a method of padding a reference image outside area 65 using inter-prediction information of a block adjacent to an inside of an outline 63 of a reference image 61 according to an embodiment is applied. The reference image outside area 65 located outside the outline line 63 of the reference image 61 is included in the other image to be referenced indicated by the inter prediction information of the adjacent block inside the outline line 63 Can be padded using reference samples. Therefore, a portion 67 of the reference image outside area 65 may be generated so as to include an area not included in the reference image 61. [

In the reference image of FIG. 5, inner samples adjacent to the outline of the reference image are copied, and an area outside the outline is padded, but substantially no information is included more than the inner information of the reference image 51. 6, the reference image outside area 65 outside the outline 63 is predicted using the prediction information of the block inside the reference image 61, so that the reference image outside area 65 May also include information that can not be obtained from within the reference image 61. Therefore, the accuracy of motion prediction using the reference image including the reference image outside area 65 is improved, and the coding efficiency of the inter prediction can be improved.

According to various embodiments, a motion prediction method to which a padding method of a reference image using prediction information is applied can be applied to a method of decoding a 360 degree image. A 360 degree image consists of a number of images taken in various directions. The existing video encoding method and video decoding method assume that the image has a rectangular shape. In order to use the existing system, a plurality of images constituting a 360 degree image are arranged in a predetermined order to constitute one image, and the existing video coding method and video decoding method are applied to the image.

FIG. 7 shows an example of a reference image of a 360-degree image to which a conventional padding method is applied.

Referring to FIG. 7, a reference image 75 of a 360-degree image is composed of images 75-1, 75-2, 75-3, 75-4, 75-5, and 75-6 photographed in six directions . Since there is no external sample value of the image outline 71 of the reference image 75 of the 360-degree image, the same value as the samples adjacent to the inside of the outline 71 of the 360- By padding, the outer region 73 of the reference image 75 of the 360 degree image can be generated.

A motion prediction method to which a padding method of a reference image outside area according to an embodiment is applied is applied to a reference image 75 of a 360-degree image of FIG.

The reference image 75 of the 360 degree image is divided into the respective images 75-1, 75-2, 75-3, 75-4, 75-5, and 75-6, Can be applied to each of the images 75-1, 75-2, 75-3, 75-4, 75-5, and 75-6.

Specifically, when the reference image is the image 75-1, based on the inter-prediction information of the outline block adjacent to the inside of the outline 81-1 of the image 75-1, The reference image outside area 83-1 can be generated.

Similarly, in each case where the reference image is the image 75-2, 75-3, 75-4, 75-5, 75-6, the image 75-2, 75-3, 75-4, 75-5 81-2 and 81-6 based on the inter prediction information of the contour blocks adjacent to the inside of the contour lines 81-2, 81-3, 81-4, 81-5, 83-3, 83-4, 83-5, and 83-6 outside the reference image region outside the reference image regions 83-2, 83-4, 81-5, and 81-6.

Accordingly, if a 360-degree image obtained by combining images photographed in various directions is divided into respective regions, and a region outside the reference image in which no sample value exists is predicted according to the inter prediction information or intra prediction information of the intra- , The accuracy of coding for each image of the 360-degree image can be further improved and the coding efficiency can be improved.

FIG. 9 illustrates an example of a 360-degree image to which a padding method of a reference image outside area is applied according to another embodiment.

In order to encode a 360-degree image, a single image is composed of a Rotated Sphere Projection (RSP), an Equirectangular Projection (ERP), an Icosahedral Projection (ISP), a Segmented Sphere Projection (SSP), a CubeMap Projection (EAC) and so on.

Depending on the format of the 360 degree image, the actual region photographed may be different from the region to be encoded. When the area to be encoded is larger than the actual area, it is a conventional method to fill the empty area other than the actual area through a method such as interpolation.

According to the format of the 360-degree image, a padding method of a reference image outside area according to an exemplary embodiment may be applied to a free area of the current image.

The reference image 90 of the 360-degree image of FIG. 9 is an image generated by Rotated Sphere Projection (RSP). The reference image 90 of the 360-degree image may include an image 95 and a free area (or padding area) 93. The reference image may be a 360 degree image 90 and the empty area 93 may exist outside the reference image outline 91. [ The sample value of the free area 93 can be predicted using the reference sample values determined using the inter prediction information or the intra prediction information of the block located inside the outline 91. [

The accuracy of the motion prediction is increased by filling the outline region outside the actual value by using the prediction information of the outline block inside the outline of the reference image.

10A is a block diagram of a video encoding apparatus 2000 to which an image padding method using prediction information according to an embodiment is applied.

The video encoding apparatus 2000 includes a predictive encoding unit 2015, a transform and quantization unit 2020, an entropy encoding unit 2025, an inverse quantization and inverse transformation unit 2030, a deblocking filtering unit 2035, (2040).

The predictive coding unit 2015 can determine prediction information for indicating a predictive sample by inter prediction or intra prediction on a current block of the input image. In the case of inter prediction, the prediction samples of the current block are determined from the reference image that has been coded first, and in the case of intra prediction, the prediction samples of the current block can be determined from the samples that are coded first in the current image.

The transform and quantization unit 2020 transforms and quantizes the residual blocks, which are difference components between the predicted samples of the predicted block and the samples of the current block, and outputs the quantized transform coefficients. The entropy encoding unit 2025 can perform entropy encoding on the quantized transform coefficients to output a bitstream. The inverse quantization and inverse transform unit 2030 performs inverse quantization and inverse transform on the quantized transform coefficients to reconstruct the residual block in the spatial domain. The reconstructed block in which the reconstructed residual block is combined with the prediction block is input to the deblocking filtering unit 2035 and the loop filtering unit 2040, and the reconstructed block is filtered and output to the reconstructed block. The reconstructed image composed of reconstructed blocks modified through loop filtering can be used as a reference image for inter prediction of the next block in the predictive coding unit 2015. [

A method of padding the outer region of the current image described above with reference to FIGS. 1A to 9 may be applied when the current block is adjacent to the outline of the current image and inter prediction information or intra prediction information for the current block exists. That is, the operation of the image padding apparatus 20 described above with reference to FIG. 2A may be performed in the predictive encoding unit 2015. FIG. The operation of the image padding device 20 performed in the predictive encoding unit 2015 is the same as the operation described above with reference to FIGS. 1A to 9, and thus a duplicated description will be omitted.

When the reference picture used for inter prediction of the current block is located outside the outline of the reference picture in the predictive coding unit 2015, the padding method of the reference picture outside region described above with reference to Figs. 1B to 9 is applied . That is, the operation of the motion prediction apparatus 21 described above with reference to FIG. 2B may be performed by the predictive encoding unit 2015. FIG. The operation of the motion prediction unit 21 performed in the predictive encoding unit 2015 is the same as the operation described above with reference to FIGS. 1B and 2B, and thus a duplicated description will be omitted.

FIG. 10B shows a block diagram of a video decoding apparatus 2080 to which an image padding method using prediction information according to an embodiment is applied.

The video decoding apparatus 2080 includes an entropy decoding unit 2055, an inverse quantization and inverse transform unit 2060, a predictive decoding unit 2075, a deblocking filtering unit 2065 and a loop filtering unit 2070.

The entropy decoding unit 2055 performs entropy decoding on the received bitstream to obtain quantized transform coefficients of the image. The inverse quantization and inverse transform unit 2060 performs inverse quantization and inverse transform on the quantized transform coefficients of the transform block to reconstruct the residual block in the spatial domain.

The prediction decoding unit 2075 can determine reference blocks of the reference block using the prediction information for inter prediction or intra prediction for the current block and determine prediction blocks using the reference samples. In case of inter prediction, the prediction samples of the current block are determined first among reconstructed reference images, and in the case of intra prediction, the prediction samples of the current block can be determined among the samples reconstructed in the current image.

A reconstruction block in the spatial domain is determined by combining the prediction block and the residual block, the sample values of the reconstruction block are modified through the deblocking filtering unit 2065 and the loop filtering unit 2070, A restored image of the current image can be output. The reconstructed image can be used as a reference image for predicting the next image in the predictive decoding unit 2075. [

Therefore, when the current block is adjacent to the outline of the current image in the predictive decoding unit 2075 and inter prediction information or intra prediction information of the current block exists, the padding method of the reference region described above with reference to FIGS. Can be applied. That is, the operation of the image padding apparatus 20 described above with reference to FIG. 2A may be performed in the predictive decoding unit 2075. [ The operation of the image padding device 20 performed in the predictive encoding unit 2075 is the same as the operation described above with reference to FIGS. 1A to 9, and thus a duplicated description will be omitted. In the case where the reference picture used for inter prediction of the current block is located outside the outline of the reference picture in the predictive decoding unit 2075, the padding method of the reference picture outside region described above with reference to Figs. 1B to 9 is applied . That is, the operation of the motion prediction apparatus 21 described above with reference to FIG. 2B may be performed in the predictive decoding unit 2075. FIG. The operation of the motion prediction apparatus 21 performed in the predictive encoding unit 2075 is the same as the operation described above with reference to FIGS. 1B and 2B, and thus a duplicated description will be omitted.

FIG. 11 illustrates a process in which the video decoding apparatus 2080 divides a current encoding unit to determine at least one encoding unit according to an embodiment.

The block shape may include 4Nx4N, 4Nx2N, 2Nx4N, 4NxN, or Nx4N. Where N may be a positive integer. The block type information is information indicating at least one of a ratio, or a size, of a shape, direction, width, and height of an encoding unit.

The shape of the encoding unit may include a square and a non-square. If the width and height of the encoding unit are the same (4Nx4N), the image decoding apparatus 2080 can determine the block type information of the encoding unit as a square. The image decoding apparatus 2080 can determine the shape of the encoding unit to be non-square.

If the width and height of the encoding unit are different (4Nx2N, 2Nx4N, 4NxN or Nx4N), the image decoding apparatus 2080 can determine the block type information of the encoding unit as a non-square. If the shape of the coding unit is a non-square shape, the image decoding apparatus 2080 divides the width and height ratio of the block type information of the coding unit by 1: 2, 2: 1, 1: 4, 4: Or 8: 1. Further, based on the length of the width of the coding unit and the length of the height, the video decoding apparatus 2080 can determine whether the coding unit is the horizontal direction or the vertical direction. Further, the image decoding apparatus 2080 can determine the size of the encoding unit based on at least one of the width of the encoding unit, the length of the height, and the width.

According to an exemplary embodiment, the image decoding apparatus 2080 can determine a type of an encoding unit using block type information and determine a type of an encoding unit to be divided using information on the division type mode. That is, the division method of the coding unit indicated by the information on the division mode can be determined according to which block type the block type information used by the video decoding apparatus 2080 represents.

The image decoding apparatus 2080 can obtain information on the split mode mode from the bit stream. However, the present invention is not limited thereto, and the image decoding apparatus 2080 and the image encoding apparatus 2200 can acquire information on the promised split mode mode on the basis of the block type information. The image decoding apparatus 2080 can acquire information on the promised divided mode mode for the maximum encoding unit or the minimum encoding unit. For example, the image decoding apparatus 2080 can determine the size of the maximum encoding unit to be 256x256. The image decoding apparatus 2080 can determine the information about the promised division mode in advance by quad split. Quad partitioning is a split mode mode that bisects both the width and the height of the encoding unit. The image decoding apparatus 2080 can obtain a 128x128 encoding unit from the maximum encoding unit of 256x256 size based on the information on the split mode mode. Also, the image decoding apparatus 2080 can determine the size of the minimum encoding unit to be 4x4. The image decoding apparatus 2080 can acquire information on the division mode mode indicating "not divided" for the minimum encoding unit.

According to an exemplary embodiment, the image decoding apparatus 2080 may use block type information indicating that the current encoding unit is a square format. For example, the image decoding apparatus 2080 can determine whether to divide a square encoding unit into vertically, horizontally, or four encoding units according to the information on the split mode mode. 11, when the block type information of the current encoding unit 300 indicates a square shape, the video decoding apparatus 2080 decodes the current encoding unit 300 according to information on the split mode mode indicating that the current block is not divided, It is possible to determine the divided

coding units

310b, 310c, and 310d based on the information on the division mode mode indicating the predetermined division method, without dividing the coding unit 310a having the same size as the coding unit 310a.

Referring to FIG. 11, the image decoding apparatus 2080 includes two encoding units 310b (FIG. 11) that divide a current encoding unit 300 in the vertical direction based on information on a split mode mode indicating that the image is divided vertically according to an embodiment. Can be determined. The image decoding apparatus 2080 can determine two encoding units 310c in which the current encoding unit 300 is divided in the horizontal direction based on the information on the split mode mode indicating that the image is divided in the horizontal direction. The image decoding apparatus 2080 can determine four encoding units 310d obtained by dividing the current encoding unit 300 in the vertical direction and the horizontal direction based on the information on the split mode mode indicating that the image is divided vertically and horizontally have. However, the division type in which the square encoding unit can be divided should not be limited to the above-mentioned form, but may include various forms in which the information on the division type mode can be represented. The predetermined divisional form in which the square encoding unit is divided will be described in detail by way of various embodiments below.

FIG. 12 illustrates a process in which the image decoding apparatus 2080 determines at least one encoding unit by dividing a non-square encoding unit according to an embodiment.

According to an exemplary embodiment, the image decoding apparatus 2080 may use block type information indicating that the current encoding unit is a non-square format. The image decoding apparatus 2080 can determine whether to divide the non-square current encoding unit according to the information on the split mode mode or not in a predetermined method. 12, when the block type information of the

current encoding unit

400 or 450 indicates a non-square shape, the image decoding apparatus 2080 decodes the current encoding The

encoding unit

410 or 460 having the same size as the

unit

400 or 450 is determined or the

encoding unit

420a, 420b, 430a, or 430b divided based on the information on the division mode mode indicating the predetermined division method , 430c, 470a, 470b, 480a, 480b, 480c. The predetermined division method in which the non-square coding unit is divided will be described in detail through various embodiments.

According to an exemplary embodiment, the image decoding apparatus 2080 may determine a type in which an encoding unit is divided using information on a split mode mode. In this case, information on the split mode mode may include at least one Lt; / RTI > can be represented by the number of encoding units. Referring to FIG. 12, when the information on the split mode mode indicates that the

current encoding unit

400 or 450 is divided into two encoding units, the image decoding apparatus 2080 decodes the current encoding The

unit

400 or 450 may be divided to determine two

encoding units

420a, 420b, or 470a and 470b included in the current encoding unit.

When the image decoding apparatus 2080 divides the

current encoding unit

400 or 450 in the form of a non-square based on the information on the split mode mode, the image decoding apparatus 2080 decodes the non- The current encoding unit can be divided in consideration of the position of the long side of the current encoding unit (400 or 450). For example, the image decoding apparatus 2080 divides the

current encoding unit

400 or 450 in the direction of dividing the longer side of the

current encoding unit

400 or 450 in consideration of the type of the

current encoding unit

400 or 450 So that a plurality of encoding units can be determined.

According to one embodiment, when the information on the split mode mode indicates that an encoding unit is divided into an odd number of blocks (tri-split), the image decoding apparatus 2080 includes the

current encoding unit

400 or 450 An odd number of encoding units can be determined. For example, when the information on the split mode mode indicates that the

current encoding unit

400 or 450 is divided into three encoding units, the image decoding device 2080 encodes the

current encoding unit

400 or 450 into three encoding Can be divided into

units

430a, 430b, 430c, 480a, 480b, and 480c.

According to one embodiment, the ratio of the width and height of the

current encoding unit

400 or 450 may be 4: 1 or 1: 4. If the ratio of width to height is 4: 1, the length of the width is longer than the length of the height, so the block type information may be horizontal. If the ratio of width to height is 1: 4, the block type information may be vertical because the length of the width is shorter than the length of the height. The image decoding apparatus 2080 can determine to divide the current encoding unit into odd number blocks based on the information on the split mode mode. The image decoding apparatus 2080 can determine the division direction of the

current encoding unit

400 or 450 based on the block type information of the

current encoding unit

400 or 450. [ For example, when the current encoding unit 400 is the vertical direction, the image decoding apparatus 2080 can determine the

encoding units

430a, 430b, and 430c by dividing the current encoding unit 400 in the horizontal direction. If the current encoding unit 450 is in the horizontal direction, the image decoding apparatus 2080 can determine the

encoding units

480a, 480b, and 480c by dividing the current encoding unit 450 in the vertical direction.

According to an exemplary embodiment, the image decoding apparatus 2080 may determine an odd number of encoding units included in the

current encoding unit

400 or 450, and the sizes of the determined encoding units may not be the same. For example, the size of a

predetermined encoding unit

430b or 480b among the determined odd number of

encoding units

430a, 430b, 430c, 480a, 480b, and 480c is different from the size of the

other encoding units

430a, 430c, 480a, and 480c . That is, an encoding unit that can be determined by dividing the current encoding unit (400 or 450) may have a plurality of types of sizes, and an odd number of encoding units (430a, 430b, 430c, 480a, 480b, 480c) May have different sizes.

According to one embodiment, when the information on the split mode mode indicates that an encoding unit is divided into an odd number of blocks, the image decoding apparatus 2080 can determine an odd number of encoding units included in the

current encoding unit

400 or 450 Further, the image decoding apparatus 2080 may set a predetermined restriction on at least one encoding unit among odd number of encoding units generated by division. Referring to FIG. 12, the image decoding apparatus 2080 decodes an encoding unit (not shown) located at the center among the three

encoding units

430a, 430b, 430c, 480a, 480b, and 480c generated by dividing the

current encoding unit

400 or 450, The decoding process for the

coding units

430b and 480b may be different from the

coding units

430a, 430c, 480a, and 480c. For example, the image decoding apparatus 2080 may restrict the

coding units

430b and 480b positioned at the center to be not further divided unlike the

other coding units

430a, 430c, 480a, and 480c, It can be limited to be divided.

FIG. 13 illustrates a process in which an image decoding apparatus 2080 divides an encoding unit based on at least one of information on a block format information and a format mode according to an embodiment.

According to one embodiment, the image decoding apparatus 2080 decides not to divide or divide the first encoding unit 500 of the square shape into encoding units based on at least one of the information on the block type information and the information on the division mode mode . If the information on the split mode mode indicates that the first encoding unit 500 is divided in the horizontal direction according to the embodiment, the image decoding apparatus 2080 divides the first encoding unit 500 in the horizontal direction, 2 encoding unit 510, as shown in FIG. The first encoding unit, the second encoding unit, and the third encoding unit used according to an embodiment are terms used to understand the relation before and after the division between encoding units. For example, if the first encoding unit is divided, the second encoding unit can be determined, and if the second encoding unit is divided, the third encoding unit can be determined. Hereinafter, the relationship between the first coding unit, the second coding unit and the third coding unit used can be understood to be in accordance with the above-mentioned characteristic.

According to an exemplary embodiment, the image decoding apparatus 2080 may determine that the determined second encoding unit 510 is not divided or divided into encoding units based on at least one of the block type information and the information on the split mode mode . 13, the image decoding apparatus 2080 decodes the first encoding unit 500 based on at least one of information on the block type information and the information on the split mode, 510) may be divided into at least one

third encoding unit

520a, 520b, 520c, 520d, or the second encoding unit 510 may not be divided. The image decoding apparatus 2080 may acquire at least one of information on the block type information and the division mode mode and the image decoding apparatus 2080 may acquire the block type information on the basis of at least one of the acquired block type information and the information on the division mode mode The second encoding unit 510 may divide the first encoding unit 500 into a plurality of second encoding units of various types (for example, 510), and the second encoding unit 510 may divide the block type information and the information The first encoding unit 500 may be divided according to a manner in which the first encoding unit 500 is divided. When the first encoding unit 500 is divided into the second encoding units 510 based on at least one of the block type information for the first encoding unit 500 and the information about the

split mode mode

520b, 520c, and 520d (e.g., 520a, 520b, 520c, and 520d) based on at least one of the block type information on the second encoding unit 510 and the information on the split mode mode, Etc.). That is, the encoding unit may be recursively divided based on at least one of the information on the split mode mode and the block type information associated with each of the encoding units. Therefore, a square encoding unit may be determined in a non-square encoding unit, and a non-square encoding unit may be determined by dividing the square encoding unit recursively.

Referring to FIG. 13, among the odd

third encoding units

520b, 520c, and 520d in which the non-square second encoding unit 510 is divided and determined, predetermined encoding units (for example, An encoding unit or a square-shaped encoding unit) can be recursively divided. According to an exemplary embodiment, the square-shaped third coding unit 520b, which is one of the odd-numbered

third coding units

520b, 520c, and 520d, may be divided in the horizontal direction and divided into a plurality of fourth coding units. The non-square

fourth encoding unit

530b or 530d, which is one of the plurality of

fourth encoding units

530a, 530b, 530c, and 530d, may be further divided into a plurality of encoding units. For example, the

fourth encoding unit

530b or 530d in the non-square form may be divided again into odd number of encoding units. A method which can be used for recursive division of an encoding unit will be described later in various embodiments.

According to one embodiment, the image decoding apparatus 2080 divides each of the

third encoding units

520a, 520b, 520c, and 520d into encoding units based on at least one of the block type information and the information on the split mode mode . Also, the image decoding apparatus 2080 may determine that the second encoding unit 510 is not divided based on at least one of the block type information and the information on the split mode mode. The image decoding apparatus 2080 may divide the non-square-shaped second coding unit 510 into odd-numbered

third coding units

520b, 520c and 520d according to an embodiment. The image decoding apparatus 2080 may set a predetermined limit on a predetermined third encoding unit among odd numbered

third encoding units

520b, 520c, and 520d. For example, the image decoding apparatus 2080 may limit the encoding unit 520c located in the middle among the odd numbered

third encoding units

520b, 520c, and 520d to no longer be divided, or be divided into a set number of times .

13, the image decoding apparatus 2080 includes an encoding unit (not shown) located in the middle among the odd

third encoding units

520b, 520c, and 520d included in the second encoding unit 510 in the non- 520c may not be further divided or may be limited to being divided into a predetermined division form (for example, divided into four coding units only or divided into a form corresponding to a form in which the second coding units 510 are divided) (For example, dividing only n times, n > 0). The above restriction on the coding unit 520c positioned at the center is merely an example and should not be construed to be limited to the above embodiments and the coding unit 520c positioned at the center is not limited to the

coding units

520b and 520d Quot;), < / RTI > which can be decoded differently.

According to one embodiment, the image decoding apparatus 2080 can acquire at least one of the block type information used for dividing the current encoding unit and the information about the split mode using a predetermined position in the current encoding unit.

FIG. 14 illustrates a method for an image decoding apparatus 2080 to determine a predetermined encoding unit among odd number of encoding units according to an embodiment.

Referring to FIG. 14, at least one of the block type information of the

current encoding units

600 and 650 and the information of the split mode mode is a sample of a predetermined position among a plurality of samples included in the

current encoding units

600 and 650 For example,

samples

640 and 690 positioned in the middle). However, the predetermined position in the current coding unit 600 in which at least one of the block type information and the division mode information can be obtained should not be limited to the middle position shown in Fig. 14, It should be understood that various positions (e.g., top, bottom, left, right, top left, bottom left, top right, or bottom right, etc.) that may be included in unit 600 may be included. The video decoding apparatus 2080 may determine that the current encoding unit is divided or not divided into encoding units of various types and sizes by acquiring at least one of the block type information and the division type mode information obtained from the predetermined position .

According to one embodiment, when the current encoding unit is divided into a predetermined number of encoding units, the image decoding apparatus 2080 can select one of the encoding units. The method for selecting one of the plurality of encoding units may be various, and description of these methods will be described later in various embodiments.

According to an exemplary embodiment, the image decoding apparatus 2080 may divide the current encoding unit into a plurality of encoding units and determine a predetermined encoding unit.

According to an exemplary embodiment, the image decoding apparatus 2080 may use information indicating the positions of odd-numbered coding units in order to determine a coding unit located in the middle among odd-numbered coding units. 14, the image decoding apparatus 2080 divides the current encoding unit 600 or the current encoding unit 650 into odd number of

encoding units

620a, 620b, and 620c or odd number of

encoding units

660a, 660b, and 660c. The image decoding apparatus 2080 decodes the encoded data in the middle encoding unit 620b or the middle encoding unit 620b using information on the positions of odd number of

encoding units

620a, 620b, and 620c or odd number of

encoding units

660a, 660b, and 660c. (660b). For example, the image decoding apparatus 2080 determines the positions of the

encoding units

620a, 620b, and 620c based on information indicating the positions of predetermined samples included in the

encoding units

620a, 620b, and 620c, The encoding unit 620b located in the encoding unit 620b can be determined. Specifically, the image decoding apparatus 2080 decodes the

encoding units

620a, 620b, and 620c based on information indicating the positions of the upper

left samples

630a, 630b, and 630c of the

encoding units

620a, 620b, and 620c, The encoding unit 620b located in the center can be determined.

Information indicating the positions of the upper

left samples

630a, 630b, and 630c included in the

coding units

620a, 620b, and 620c according to one embodiment is stored in the pictures of the

coding units

620a, 620b, and 620c Or information about the position or coordinates of the object. Information indicating the positions of the upper

left samples

630a, 630b, and 630c included in the

coding units

620a, 620b, and 620c according to one embodiment is stored in the

coding units

620a , 620b, and 620c, and the width or height may correspond to information indicating the difference between the coordinates of the

encoding units

620a, 620b, and 620c in the picture. That is, the image decoding apparatus 2080 directly uses the information on the position or the coordinates in the pictures of the

coding units

620a, 620b, and 620c or the information on the width or height of the coding units corresponding to the difference between the coordinates The encoding unit 620b located in the center can be determined.

According to one embodiment, the information indicating the position of the upper left sample 630a of the upper coding unit 620a may indicate the coordinates (xa, ya) and the upper left sample 530b of the middle coding unit 620b May indicate the coordinates (xb, yb), and the information indicating the position of the upper left sample 630c of the lower coding unit 620c may indicate the coordinates (xc, yc). The image decoding apparatus 2080 can determine the center encoding unit 620b using the coordinates of the upper

left samples

630a, 630b, and 630c included in the

encoding units

620a, 620b, and 620c. 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 (xb, yb) coordinates of the sample 630b located at the center, Can be determined as a coding unit located in the middle of the

coding units

620a, 620b, and 620c determined by dividing the current coding unit 600. [ However, the coordinates indicating the positions of the

samples

630a, 630b and 630c in the upper left corner may indicate the coordinates indicating the absolute position in the picture, and the position of the upper left sample 630a of the upper coding unit 620a may be (Dxb, dyb), which is information indicating the relative position of the sample 630b at the upper left of the middle encoding unit 620b, and the relative position of the sample 630c at the upper left of the lower encoding unit 620c Information dyn (dxc, dyc) coordinates may also be used. Also, the method of determining the coding unit at a predetermined position by using the coordinates of the sample as information indicating the position of the sample included in the coding unit should not be limited to the above-described method, and various arithmetic Should be interpreted as a method.

According to an embodiment, the image decoding apparatus 2080 may divide the current encoding unit 600 into a plurality of

encoding units

620a, 620b, and 620c, and may encode a predetermined one of the

encoding units

620a, 620b, and 620c The encoding unit can be selected according to the criterion. For example, the image decoding apparatus 2080 can select an encoding unit 620b having a different size from among the encoding

units

620a, 620b, and 620c.

The image decoding apparatus 2080 according to an embodiment of the present invention includes a (xa, ya) coordinate which is information indicating the position of the upper left sample 630a of the upper encoding unit 620a, (Xc, yc) coordinates, which is information indicating the position of the lower-stage coding unit 630b and the position of the upper-left sample 630c of the lower-

stage coding unit

620c, , 620b, and 620c, respectively. The image decoding apparatus 2080 decodes the

encoding units

620a and 620b using the coordinates (xa, ya), (xb, yb), (xc, yc) indicating the positions of the

encoding units

620a, 620b and 620c , And 620c, respectively. According to one embodiment, the image decoding apparatus 2080 can determine the width of the upper encoding unit 620a as the width of the current encoding unit 600. [ The image decoding apparatus 2080 can determine the height of the upper encoding unit 620a as yb-ya. The image decoding apparatus 2080 may determine the width of the middle encoding unit 620b as the width of the current encoding unit 600 according to an embodiment. The image decoding apparatus 2080 can determine the height of the center encoding unit 620b as yc-yb. The image decoding apparatus 2080 can determine the width or height of the lower coding unit by using the width or height of the current coding unit and the width and height of the upper coding unit 620a and the middle coding unit 620b . The image decoding apparatus 2080 can determine an encoding unit having a different size from the other encoding units based on the widths and heights of the

determined encoding units

620a, 620b, and 620c. Referring to FIG. 14, the image decoding apparatus 2080 can determine a coding unit 620b as a coding unit at a predetermined position while having a size different from that of the upper coding unit 620a and the lower coding unit 620c. The process of determining the encoding unit having a size different from that of the other encoding units by the image decoding apparatus 2080 may be the same as that of the first embodiment in which the encoding unit of a predetermined position is determined using the size of the encoding unit determined based on the sample coordinates , Various processes may be used for determining the encoding unit at a predetermined position by comparing the sizes of the encoding units determined according to predetermined sample coordinates.

The image decoding apparatus 2080 decodes the position of the left upper sample 670a of the left coding unit 660a and the position (xd, yd) of the left upper sample of the left coding unit 660b of the

middle coding unit

660b, 660b and 660c using the (xf, yf) coordinates, which is information indicating the (xe, ye) coordinate which is the information indicating the position of the right encoding unit 660c and the position of the sample 670c at the upper left of the right encoding unit 660c, Each width or height can be determined. The image decoding apparatus 2080 decodes the

encoding units

660a and 660b using the coordinates (xd, yd), (xe, ye), (xf, yf) indicating the positions of the

encoding units

660a, 660b and 660c And 660c, respectively.

According to one embodiment, the image decoding apparatus 2080 can determine the width of the left encoding unit 660a as xe-xd. The image decoding apparatus 2080 can determine the height of the left encoding unit 660a as the height of the current encoding unit 650. [ According to an embodiment, the image decoding apparatus 2080 can determine the width of the middle encoding unit 660b as xf-xe. The image decoding apparatus 2080 can determine the height of the middle encoding unit 660b as the height of the current encoding unit 600. [ The width or height of the right encoding unit 660c is determined by the width or height of the current encoding unit 650 and the width and height of the left encoding unit 660a and the middle encoding unit 660b . &Lt; / RTI > The image decoding apparatus 2080 can determine an encoding unit having a different size from the other encoding units based on the widths and heights of the

determined encoding units

660a, 660b, and 660c. Referring to FIG. 14, the image decoding apparatus 2080 can determine a coding unit 660b as a coding unit at a predetermined position while having a size different from that of the left coding unit 660a and the right coding unit 660c. The process of determining the encoding unit having a size different from that of the other encoding units by the image decoding apparatus 2080 may be the same as that of the first embodiment in which the encoding unit of a predetermined position is determined using the size of the encoding unit determined based on the sample coordinates , Various processes may be used for determining the encoding unit at a predetermined position by comparing the sizes of the encoding units determined according to predetermined sample coordinates.

However, the position of the sample to be considered for determining the position of the coding unit should not be interpreted as being limited to the left upper end, and information about the position of any sample included in the coding unit can be interpreted as being available.

According to one embodiment, the image decoding apparatus 2080 can select a coding unit at a predetermined position among the odd number of coding units determined by dividing the current coding unit considering the type of the current coding unit. For example, if the current coding unit is a non-square shape having a width greater than the height, the image decoding apparatus 2080 can determine a coding unit at a predetermined position along the horizontal direction. That is, the image decoding apparatus 2080 may determine one of the encoding units which are located in the horizontal direction and limit the encoding unit. If the current coding unit is a non-square shape having a height greater than the width, the image decoding apparatus 2080 can determine a coding unit at a predetermined position in the vertical direction. That is, the image decoding apparatus 2080 may determine one of the encoding units which are located in the vertical direction and limit the encoding unit.

According to an exemplary embodiment, the image decoding apparatus 2080 may use information indicating positions of even-numbered encoding units in order to determine an encoding unit of a predetermined position among the even-numbered encoding units. The image decoding apparatus 2080 can determine an even number of coding units by binary coding the current coding unit and determine a coding unit at a predetermined position using information on the positions of even number of coding units. A concrete procedure for this is omitted because it may be a process corresponding to a process of determining a coding unit of a predetermined position (for example, the middle position) among the above-mentioned odd number of coding units in FIG.

According to one embodiment, when a non-square current encoding unit is divided into a plurality of encoding units, in order to determine an encoding unit at a predetermined position among a plurality of encoding units, Can be used. For example, in order to determine an encoding unit located in the middle among the plurality of encoding units in which the current encoding unit is divided, the image decoding apparatus 2080 decodes the block type information stored in the sample included in the middle encoding unit, Mode may be used.

14, the image decoding apparatus 2080 divides the current encoding unit 600 into a plurality of

encoding units

620a, 620b, and 620c based on at least one of information on the block type information and the information on the split mode mode And the encoding unit 620b located in the middle of the plurality of

encoding units

620a, 620b, and 620c can be determined. Furthermore, the image decoding apparatus 2080 can determine a coding unit 620b positioned at the center in consideration of the position at which at least one of the block type information and the division type mode information is obtained. That is, at least one of the block type information of the current encoding unit 600 and the information of the division mode mode can be obtained in the sample 640 located in the middle of the current encoding unit 600, If the current encoding unit 600 is divided into a plurality of

encoding units

620a, 620b, and 620c based on at least one of the information on the division mode mode and the encoding unit 620b including the sample 640, As shown in FIG. The information used for determining the encoding unit located in the middle should not be limited to at least one of the block type information and the information about the division mode mode, and a process of determining an encoding unit in which various types of information are located in the middle &Lt; / RTI >

According to an embodiment, predetermined information for identifying a coding unit at a predetermined position may be obtained from a predetermined sample included in a coding unit to be determined. 14, the image decoding apparatus 2080 encodes a predetermined number of coding units (for example, a plurality of divided coding units) among a plurality of

coding units

620a, 620b, and 620c determined by dividing the current coding unit 600 (For example, a sample located in the middle of the current encoding unit 600) at a predetermined position in the current encoding unit 600 in order to determine an encoding unit located in the middle of the encoding unit, And at least one of information on the split mode mode may be used. That is, the image decoding apparatus 2080 can determine the sample of the predetermined position in consideration of the block form of the current encoding unit 600, and the image decoding apparatus 2080 decodes the plural A coding unit 620b including samples from which predetermined information (for example, at least one of information on the block type information and the division mode information) can be obtained from the plurality of

coding units

620a, 620b, and 620c So that a predetermined limit can be set. Referring to FIG. 14, the image decoding apparatus 2080 can determine a sample 640 positioned in the center of the current encoding unit 600 as a sample from which predetermined information can be obtained, The coding unit 2080 may limit the coding unit 620b including the sample 640 to a predetermined limit in the decoding process. However, the position of the sample from which the predetermined information can be obtained should not be construed to be limited to the above-mentioned position, but may be interpreted as samples at arbitrary positions included in the encoding unit 620b to be determined for limiting.

The position of a sample from which predetermined information can be obtained according to one embodiment may be determined according to the type of the current encoding unit 600. [ According to one embodiment, the block type information can determine whether the current encoding unit is a square or a non-square, and determine the position of a sample from which predetermined information can be obtained according to the shape. For example, the video decoding apparatus 2080 may use at least one of the information on the width of the current coding unit and the information on the height to position at least one of the width and the height of the current coding unit in half The sample can be determined as a sample from which predetermined information can be obtained. For example, when the block type information relating to the current encoding unit is a non-square type, the image decoding apparatus 2080 decodes one of the samples adjacent to the boundary dividing the longer side of the current encoding unit into half, Can be determined as a sample from which the information of < / RTI >

According to one embodiment, when the current encoding unit is divided into a plurality of encoding units, the image decoding apparatus 2080 decodes the block type information and the split mode mode to determine a coding unit of a predetermined position among the plurality of encoding units. Information can be used. According to one embodiment, the image decoding apparatus 2080 can acquire at least one of the block type information and the information on the split mode mode from a sample of a predetermined position included in the encoding unit, and the image decoding apparatus 2080 The plurality of coding units generated by dividing the unit may be divided using at least one of the information on the division mode and the block type information obtained from the sample at the predetermined position included in each of the plurality of the coding units. That is, the coding unit can be recursively divided using at least one of the block type information obtained in the sample at the predetermined position included in each of the coding units and the information about the division mode. The recursive division process of the encoding unit is described in detail with reference to FIG. 13, and a detailed description thereof will be omitted.

According to an exemplary embodiment, the image decoding apparatus 2080 can determine at least one encoding unit by dividing the current encoding unit, and the order in which the at least one encoding unit is decoded is determined as a predetermined block (for example, ). &Lt; / RTI >

FIG. 15 shows a sequence in which a plurality of coding units are processed when the image decoding apparatus 2080 determines a plurality of coding units by dividing a current coding unit according to an embodiment.

According to one embodiment, the image decoding apparatus 2080 divides the first encoding unit 700 in the vertical direction according to the information on the block type information and the division mode, thereby determining the

second encoding units

710a and 710b, The

second encoding units

730a and 730b may be determined by dividing the first encoding units 700a to 750c by dividing the first encoding units 700a and 750b in the horizontal direction to divide the first encoding units 700 in the vertical direction and the horizontal direction, , 750d can be determined.

15, the image decoding apparatus 2080 can determine the order in which the

second encoding units

710a and 710b determined by dividing the first encoding unit 700 in the vertical direction are processed in the horizontal direction 710c . The image decoding apparatus 2080 can determine the processing order of the

second encoding units

730a and 730b determined by dividing the first encoding unit 700 in the horizontal direction as the vertical direction 730c. The image decoding apparatus 2080 processes the encoding units located in one row of the

second encoding units

750a, 750b, 750c, and 750d determined by dividing the first encoding unit 700 in the vertical direction and the horizontal direction, (For example, a raster scan order or a z scan order 750e) in which the encoding units located in the next row are processed.

According to an embodiment, the image decoding apparatus 2080 can recursively divide encoding units. 15, the image decoding apparatus 2080 can determine a plurality of

encoding units

710a, 710b, 730a, 730b, 750a, 750b, 750c and 750d by dividing the first encoding unit 700, The determined plurality of

encoding units

710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d can be recursively divided. The method of dividing the plurality of

encoding units

710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d may be a method corresponding to the method of dividing the first encoding unit 700. [ Accordingly, the plurality of

encoding units

710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d may be independently divided into a plurality of encoding units. 15, the image decoding apparatus 2080 can determine the

second encoding units

710a and 710b by dividing the first encoding unit 700 in the vertical direction, and can further determine the

second encoding units

710a and 710b Can be determined not to divide or separate independently.

The image decoding apparatus 2080 may divide the second encoding unit 710a on the left side in the horizontal direction into the third encoding units 720a and 720b and the second encoding units 710b ) May not be divided.

According to an embodiment, the processing order of the encoding units may be determined based on the division process of the encoding units. In other words, the processing order of the divided coding units can be determined based on the processing order of the coding units immediately before being divided. The image decoding apparatus 2080 can independently determine the order in which the third encoding units 720a and 720b determined by dividing the second encoding unit 710a on the left side are processed to the second encoding unit 710b on the right side. The third encoding units 720a and 720b may be processed in the vertical direction 720c because the second encoding units 710a on the left side are divided in the horizontal direction and the third encoding units 720a and 720b are determined. Since the order in which the left second encoding unit 710a and the right second encoding unit 710b are processed corresponds to the horizontal direction 710c, the third encoding unit 710a included in the left second encoding unit 710a, The right encoding unit 710b can be processed after the blocks 720a and 720b are processed in the vertical direction 720c. The above description is intended to explain the process sequence in which encoding units are determined according to the encoding units before division. Therefore, it should not be construed to be limited to the above-described embodiments, It should be construed as being used in various ways that can be handled independently in sequence.

16 illustrates a process of determining that the current encoding unit is divided into odd number of encoding units when the image decoding apparatus 2080 can not process the encoding units in a predetermined order according to an embodiment.

According to one embodiment, the image decoding apparatus 2080 can determine that the current encoding unit is divided into odd number of encoding units based on the obtained block type information and information on the split mode mode. Referring to FIG. 16, the first encoding unit 800 in the form of a square may be divided into second

non-square encoding units

810a and 810b, and the

second encoding units

810a and 810b may be independently 3

encoding units

820a, 820b, 820c, 820d, and 820e. According to an embodiment, the image decoding apparatus 2080 can determine the plurality of

third encoding units

820a and 820b by dividing the left encoding unit 810a of the second encoding unit in the horizontal direction, and the right encoding unit 810b Can be divided into an odd number of

third encoding units

820c, 820d, and 820e.

According to one embodiment, the image decoding apparatus 2080 determines whether or not the

third encoding units

820a, 820b, 820c, 820d, and 820e can be processed in a predetermined order and determines whether there are odd-numbered encoding units You can decide. Referring to FIG. 16, the image decoding apparatus 2080 can recursively divide the first encoding unit 800 to determine the

third encoding units

820a, 820b, 820c, 820d, and 820e. The image decoding apparatus 2080 may encode the first encoding unit 800, the

second encoding units

810a and 810b or the

third encoding units

820a and 820b based on at least one of the block type information and the information on the split mode mode , 820c, 820d, and 820e are divided into odd number of coding units among the divided types. For example, an encoding unit located on the right of the

second encoding units

810a and 810b may be divided into odd

third encoding units

820c, 820d, and 820e. The order in which the plurality of coding units included in the first coding unit 800 are processed may be a predetermined order (for example, a z-scan order 830) 2080 can determine whether the

third encoding units

820c, 820d, and 820e determined by dividing the right second encoding unit 810b into odd numbers satisfy the condition that the

third encoding units

820c, 820d, and 820e can be processed according to the predetermined order.

According to an embodiment, the image decoding apparatus 2080 satisfies the condition that the

third encoding units

820a, 820b, 820c, 820d, and 820e included in the first encoding unit 800 can be processed in a predetermined order And it is determined whether or not at least one of the widths and heights of the

second encoding units

810a and 810b is divided in half according to the boundaries of the

third encoding units

820a, 820b, 820c, 820d, and 820e, . For example, the

third encoding units

820a and 820b, which are determined by dividing the height of the left second encoding unit 810a in the non-square shape by half, can satisfy the condition. The boundaries of the

third encoding units

820c, 820d, and 820e determined by dividing the right second encoding unit 810b into three encoding units do not divide the width or height of the right second encoding unit 810b in half , The

third encoding units

820c, 820d, and 820e may be determined as not satisfying the condition. The image decoding apparatus 2080 may determine that the scan sequence is disconnection in the case of such unsatisfactory condition and determine that the right second encoding unit 810b is divided into odd number of encoding units based on the determination result. According to an exemplary embodiment, the image decoding apparatus 2080 may limit a coding unit at a predetermined position among the divided coding units when the coding unit is divided into odd number of coding units. Since the embodiment has been described above, a detailed description thereof will be omitted.

FIG. 17 illustrates a process in which the image decoding apparatus 2080 determines at least one encoding unit by dividing a first encoding unit 900 according to an embodiment.

According to one embodiment, the image decoding apparatus 2080 can divide the first encoding unit 900 based on at least one of the block type information obtained through the entropy decoding unit 2055 and the information on the split mode mode . The first coding unit 900 in the form of a square may be divided into four coding units having a square form, or may be divided into a plurality of non-square coding units. For example, referring to FIG. 17, if the block type information indicates that the first encoding unit 900 is square, and the information on the split mode mode is divided into non-square encoding units, the image decoding apparatus 2080 1 encoding unit 900 into a plurality of non-square encoding units. More specifically, when the information on the split mode mode indicates that the first encoding unit 900 is divided horizontally or vertically to determine an odd number of encoding units, the image decoding apparatus 2080 decodes the first encoding The unit 900 can be divided into the

second coding units

910a, 910b and 910c divided in the vertical direction as the odd number of coding units or the

second coding units

920a, 920b and 920c divided in the horizontal direction .

According to an exemplary embodiment, the image decoding apparatus 2080 may be configured such that the

second encoding units

910a, 910b, 910c, 920a, 920b, and 920c included in the first encoding unit 900 are processed in a predetermined order And the condition is that at least one of the width and the height of the first encoding unit 900 is divided in half according to the boundaries of the

second encoding units

910a, 910b, 910c, 920a, 920b, and 920c . 17, the boundaries of the

second encoding units

910a, 910b, and 910c, which are determined by dividing the first encoding unit 900 in the vertical direction into a square shape, are divided in half by the width of the first encoding unit 900 The first encoding unit 900 can be determined as not satisfying a condition that can be processed in a predetermined order. In addition, since the boundaries of the

second encoding units

920a, 920b, and 920c, which are determined by dividing the first encoding unit 900 in the horizontal direction into the horizontal direction, can not divide the width of the first encoding unit 900 in half, 1 encoding unit 900 may be determined as not satisfying a condition that can be processed in a predetermined order. The image decoding apparatus 2080 may determine that the scan sequence is disconnection in the case of such unsatisfactory condition and determine that the first encoding unit 900 is divided into odd number of encoding units based on the determination result. According to an exemplary embodiment, the image decoding apparatus 2080 may limit a coding unit at a predetermined position among the divided coding units when the coding unit is divided into odd number of coding units. Since the embodiment has been described above, a detailed description thereof will be omitted.

According to one embodiment, the image decoding apparatus 2080 may divide the first encoding unit to determine various types of encoding units.

17, the image decoding apparatus 2080 may divide a first coding unit 900 in a square form and a

first coding unit

930 or 950 in a non-square form into various types of coding units .

FIG. 18 illustrates an example in which when the non-square second encoding unit determined by dividing the first encoding unit 1000 by the image decoding apparatus 2080 satisfies a predetermined condition, the second encoding unit is divided Lt; RTI ID = 0.0 > limited. &Lt; / RTI >

According to one embodiment, the image decoding apparatus 2080 decodes the first encoding unit 1000 in the form of a square based on at least one of the block type information and the division type mode information acquired through the entropy decoding unit 2055 - the

second encoding units

1010a, 1010b, 1020a, and 1020b in the form of a square. The

second encoding units

1010a, 1010b, 1020a, and 1020b may be independently divided. Accordingly, the image decoding apparatus 2080 divides or divides the image data into a plurality of encoding units based on at least one of the block type information and the information on the split mode mode associated with each of the

second encoding units

1010a, 1010b, 1020a, and 1020b You can decide not to. According to one embodiment, the image decoding apparatus 2080 divides the non-square left second encoding unit 1010a determined by dividing the first encoding unit 1000 in the vertical direction into a horizontal direction, 1012a, and 1012b. However, when the left second encoding unit 1010a is divided in the horizontal direction, the right second encoding unit 1010b is horizontally aligned with the left second encoding unit 1010a in a direction in which the left second encoding unit 1010a is divided, As shown in Fig. If the right second encoding unit 1010b is divided in the same direction and the

third encoding units

1014a and 1014b are determined, the left second encoding unit 1010a and the right second encoding unit 1010b are arranged in the horizontal direction The

third encoding units

1012a, 1012b, 1014a, and 1014b can be determined by being independently divided. However, the image decoding apparatus 2080 may convert the first encoding unit 1000 into four square-shaped

second encoding units

1030a, 1030b, 1030c, and 1030d based on at least one of the block type information and the information on the split mode mode ), Which may be inefficient in terms of image decoding.

According to an embodiment, the image decoding apparatus 2080 divides the non-square

second encoding unit

1020a or 1020b determined by dividing the first encoding unit 1000 in the horizontal direction into a vertical direction, (1022a, 1022b, 1024a, 1024b). However, when one of the second coding units (for example, the upper second coding unit 1020a) is divided in the vertical direction, the video decoding apparatus 2080 decodes the second coding unit (for example, The encoding unit 1020b) can be restricted such that the upper second encoding unit 1020a can not be divided vertically in the same direction as the divided direction.

FIG. 19 illustrates a process in which the image decoding apparatus 2080 divides a square-shaped encoding unit when the information on the split mode mode can not indicate division into four square-shaped encoding units according to an embodiment .

According to one embodiment, the image decoding apparatus 2080 divides the first encoding unit 1100 based on at least one of information on the block type information and the information on the split mode mode to generate

second encoding units

1110a, 1110b, 1120a, and 1120b Etc.) can be determined. The information on the division type mode may include information on various types in which the coding unit can be divided, but information on various types may not include information for dividing into four square units of coding units. According to the information on the split mode mode, the image decoding apparatus 2080 can not divide the first encoding unit 1100 in the square form into the

second encoding units

1130a, 1130b, 1130c, and 1130d in the form of four squares . The image decoding apparatus 2080 can determine the

second encoding units

1110a, 1110b, 1120a, and 1120b in the non-square form based on the information on the split mode mode.

According to an exemplary embodiment, the image decoding apparatus 2080 can independently divide the non-square

second encoding units

1110a, 1110b, 1120a, and 1120b, respectively. Each of the

second encoding units

1110a, 1110b, 1120a, and 1120b may be divided in a predetermined order through a recursive method, and the

first encoding units

1110a, 1110b, 1120a, and 1120b may be divided according to at least one of the block type information, May be a division method corresponding to how the unit 1100 is divided.

For example, the image decoding apparatus 2080 can determine the

third encoding units

1112a and 1112b in the form of a square by dividing the left second encoding unit 1110a in the horizontal direction, and the second right encoding unit 1110b It is possible to determine the third encoding units 1114a and 1114b in the form of a square by being divided in the horizontal direction. Furthermore, the image decoding apparatus 2080 may divide the left second encoding unit 1110a and the right second encoding unit 1110b in the horizontal direction to determine the

third encoding units

1116a, 1116b, 1116c, and 1116d in the form of a square have. In this case, the encoding unit can be determined in the same manner as the first encoding unit 1100 is divided into the four second square encoding

units

1130a, 1130b, 1130c, and 1130d.

In another example, the image decoding apparatus 2080 can determine the third encoding units 1122a and 1122b in the shape of a square by dividing the upper second encoding unit 1120a in the vertical direction, and the lower second encoding units 1120b May be divided in the vertical direction to determine the

third encoding units

1124a and 1124b in the form of a square. Further, the image decoding apparatus 2080 may divide the upper second encoding unit 1120a and the lower second encoding unit 1120b in the vertical direction to determine the square-shaped third encoding units 1126a, 1126b, 1126a, and 1126b have. In this case, the encoding unit can be determined in the same manner as the first encoding unit 1100 is divided into the four second square encoding

units

1130a, 1130b, 1130c, and 1130d.

According to an exemplary embodiment, the image decoding apparatus 2080 may divide the first encoding unit 1200 based on information on the block type information and the split mode mode. When the block type information indicates a square shape and the information on the split mode mode indicates that the first encoding unit 1200 is divided into at least one of the horizontal direction and the vertical direction, the image decoding apparatus 2080 decodes the first encoding The unit 1200 can be divided to determine the second encoding unit (e.g., 1210a, 1210b, 1220a, 1220b, etc.). Referring to FIG. 20, the non-square

second encoding units

1210a, 1210b, 1220a, and 1220b, which are determined by dividing the first encoding unit 1200 only in the horizontal direction or the vertical direction, Can be independently divided based on information on the < / RTI > For example, the image decoding apparatus 2080 divides the

second encoding units

1210a and 1210b generated by dividing the first encoding unit 1200 in the vertical direction into the horizontal direction, and outputs the

third encoding units

1216a, 1216b, 1216c and 1216d can be determined and the

second encoding units

1220a and 1220b generated by dividing the first encoding unit 1200 in the horizontal direction are divided in the horizontal direction and the third encoding units 1226a, , 1226d. Since the process of dividing the

second encoding units

1210a, 1210b, 1220a, and 1220b has been described above with reference to FIG. 19, a detailed description thereof will be omitted.

According to an embodiment, the image decoding apparatus 2080 can process a coding unit in a predetermined order. Features of processing of a coding unit in a predetermined order have been described above with reference to FIG. 15, and a detailed description thereof will be omitted. Referring to FIG. 20, the image decoding apparatus 2080 divides a first encoding unit 1200 of a square shape into 4 pieces of

fourth encoding units

1216a, 1216b, 1216c, 1216d, 1226a, 1226b, 1226c, 1226d Can be determined. According to one embodiment, the image decoding apparatus 2080 decodes the processing order of the

third encoding units

1216a, 1216b, 1216c, 1216d, 1226a, 1226b, 1226c, and 1226d according to the form in which the first encoding unit 1200 is divided You can decide.

According to an embodiment, the image decoding apparatus 2080 divides the

second encoding units

1210a and 1210b generated in the vertical direction into horizontal units to determine the

third encoding units

1216a, 1216b, 1216c, and 1216d And the image decoding apparatus 2080 processes the

third encoding units

1216a and 1216c included in the left second encoding unit 1210a first in the vertical direction and then processes the

third encoding units

1216a and 1216c included in the right second encoding unit 1210b The

third encoding units

1216a, 1216b, 1216c, and 1216d can be processed according to the order 1217 of processing the

third encoding units

1216b and 1216d in the vertical direction.

According to an embodiment, the image decoding apparatus 2080 divides the

second encoding units

1220a and 1220b generated in the horizontal direction into vertical directions to determine the

third encoding units

1226a, 1226b, 1226c and 1226d And the image decoding apparatus 2080 first processes the third encoding units 1226a and 1226b included in the upper second encoding unit 1220a in the horizontal direction and then processes the third encoding units 1226a and 1226b included in the lower second encoding unit 1220b The

third encoding units

1226a, 1226b, 1226c, and 1226d may be processed in accordance with an order 1227 for processing the

third encoding units

1226c and 1226d in the horizontal direction.

Referring to FIG. 20, the

second encoding units

1210a, 1210b, 1220a, and 1220b are divided to determine the

third encoding units

1216a, 1216b, 1216c, 1216d, 1226a, 1226b, 1226c, and 1226d, have. The

second encoding units

1210a and 1210b determined to be divided in the vertical direction and the

second encoding units

1220a and 1220b determined to be divided in the horizontal direction are divided into different formats, but the

third encoding units

1216a , 1216b, 1216c, 1216d, 1226a, 1226b, 1226c, and 1226d, the result is that the first encoding unit 1200 is divided into the same type of encoding units. Accordingly, the image decoding apparatus 2080 divides the encoding unit recursively through different processes based on at least one of the block type information and the information about the division mode, thereby determining the same type of encoding units as a result, A plurality of encoding units may be processed in different orders.

According to an embodiment, the image decoding apparatus 2080 can determine the depth of a coding unit according to a predetermined criterion. For example, a predetermined criterion may be a length of a long side of a coding unit. When the length of the long side of the current coding unit is divided by 2n (n > 0) times longer than the length of the long side of the coding unit before the current coding unit is divided, the depth of the current coding unit is smaller than the depth of the coding unit before being divided it can be determined that the depth is increased by n. Hereinafter, an encoding unit with an increased depth is expressed as a lower-depth encoding unit.

Referring to FIG. 21, on the basis of block type information (for example, block type information may indicate '0: SQUARE') indicating a square form according to an embodiment, the image decoding apparatus 2080 may include a square- 1 encoding unit 1300 can be divided to determine the second encoding unit 1302, the third encoding unit 1304, etc. of the lower depth. If the size of the first encoding unit 1300 in the form of a square is 2Nx2N, the second encoding unit 1302 determined by dividing the width and height of the first encoding unit 1300 by 1/2 may have a size of NxN have. Further, the third encoding unit 1304 determined by dividing the width and height of the second encoding unit 1302 by a half size may have a size of N / 2xN / 2. In this case, the width and height of the third encoding unit 1304 correspond to 1/4 of the first encoding unit 1300. If the depth of the first encoding unit 1300 is D, the depth of the second encoding unit 1302, which is half the width and height of the first encoding unit 1300, may be D + 1, The depth of the third encoding unit 1304, which is one fourth of the width and height of the third encoding unit 1300, may be D + 2.

According to an exemplary embodiment, block type information indicating a non-square shape (for example, block type information is' 1: NS_VER 'indicating that the height is a non-square having a width greater than the width or' 2 >: NS_HOR '), the image decoding apparatus 2080 divides the non-square

first coding unit

1310 or 1320 into a second

lower coding unit

1312 or 1322, The third encoding unit 1314 or 1324, or the like.

The image decoding apparatus 2080 can determine a second coding unit (e.g., 1302, 1312, 1322, etc.) by dividing at least one of the width and the height of the first coding unit 1310 of Nx2N size. That is, the image decoding apparatus 2080 can determine the second encoding unit 1302 of NxN size or the second encoding unit 1322 of NxN / 2 size by dividing the first encoding unit 1310 in the horizontal direction, It is also possible to determine the second encoding unit 1312 of N / 2xN size by dividing it in the horizontal direction and the vertical direction.

According to an embodiment, the image decoding apparatus 2080 divides at least one of the width and the height of the 2NxN first encoding unit 1320 to determine a second encoding unit (for example, 1302, 1312, 1322, etc.) It is possible. That is, the image decoding apparatus 2080 can determine the second encoding unit 1302 of NxN size or the second encoding unit 1312 of N / 2xN size by dividing the first encoding unit 1320 in the vertical direction, The second encoding unit 1322 of the NxN / 2 size may be determined by dividing the image data in the horizontal direction and the vertical direction.

According to an embodiment, the image decoding apparatus 2080 divides at least one of the width and the height of the second encoding unit 1302 of NxN size to determine a third encoding unit (for example, 1304, 1314, 1324, etc.) It is possible. That is, the image decoding apparatus 2080 divides the second encoding unit 1302 in the vertical direction and the horizontal direction to determine a third encoding unit 1304 of N / 2xN / 2 size or a N / 4xN / 3 encoding unit 1314 or a third encoding unit 1324 of N / 2xN / 4 size.

According to an embodiment, the image decoding apparatus 2080 divides at least one of the width and the height of the second encoding unit 1312 of N / 2xN size into a third encoding unit (e.g., 1304, 1314, 1324, etc.) . That is, the image decoding apparatus 2080 divides the second encoding unit 1312 in the horizontal direction to generate a third encoding unit 1304 of N / 2xN / 2 or a third encoding unit 1324 of N / 2xN / 4 size ) Or may be divided in the vertical and horizontal directions to determine the third encoding unit 1314 of N / 4xN / 2 size.

The image decoding apparatus 2080 may divide at least one of the width and the height of the second encoding unit 1322 of NxN / 2 size into a third encoding unit (e.g., 1304, 1314, 1324, etc.) . That is, the image decoding apparatus 2080 divides the second encoding unit 1322 in the vertical direction to obtain a third encoding unit 1304 of N / 2xN / 2 or a third encoding unit 1314 of N / 4xN / 2 size ) Or may be divided in the vertical and horizontal directions to determine the third encoding unit 1324 of N / 2xN / 4 size.

According to an embodiment, the image decoding apparatus 2080 may divide a square-shaped encoding unit (for example, 1300, 1302, and 1304) into a horizontal direction or a vertical direction. For example, the first encoding unit 1300 having a size of 2Nx2N is divided in the vertical direction to determine a first encoding unit 1310 having a size of Nx2N or the first encoding unit 1310 having a size of 2NxN to determine a first encoding unit 1320 having a size of 2NxN . According to an exemplary embodiment, when the depth is determined based on the length of the longest side of the encoding unit, the depth of the encoding unit, which is determined by dividing the first encoding unit 1300 of 2Nx2N size in the horizontal direction or the vertical direction, May be the same as the depth of the unit (1300).

According to one embodiment, the width and height of the third encoding unit 1314 or 1324 may correspond to one fourth of the

first encoding unit

1310 or 1320. [ When the depth of the

first coding unit

1310 or 1320 is D, the depth of the

second coding unit

1312 or 1322 which is half the width and height of the

first coding unit

1310 or 1320 is D + And the depth of the third encoding unit 1314 or 1324, which is one fourth of the width and height of the

first encoding unit

1310 or 1320, may be D + 2.

According to an embodiment, the image decoding apparatus 2080 may divide the first encoding unit 1400 in a square form to determine various types of second encoding units. 22, the image decoding apparatus 2080 divides the first encoding unit 1400 into at least one of the vertical direction and the horizontal direction according to the information on the division mode mode, and outputs the

second encoding units

1402a and 1402b , 1404a, 1404b, 1406a, 1406b, 1406c, 1406d. That is, the image decoding apparatus 2080 determines the

second encoding units

1402a, 1402b, 1404a, 1404b, 1406a, 1406b, 1406c, and 1406d based on the information on the split mode mode for the first encoding unit 1400 .

The

second encoding units

1402a, 1402b, 1404a, 1404b, 1406a, 1406b, 1406c, and 1406d, which are determined according to the information on the split mode mode for the first encoding unit 1400 in the square form, The depth can be determined based on the length of the sides. For example, since the length of one side of the first encoding unit 1400 in the square form is the same as the length of long sides of the

second encoding units

1402a, 1402b, 1404a, and 1404b in the non-square form, 1400) and the non-square type

second encoding units

1402a, 1402b, 1404a, 1404b are denoted by D in the same manner. On the other hand, when the image decoding apparatus 2080 divides the first encoding unit 1400 into four square-shaped

second encoding units

1406a, 1406b, 1406c, and 1406d based on information on the split mode, The length of one side of the

second encoding units

1406a, 1406b, 1406c and 1406d in the form of the

second encoding units

1406a, 1406b, 1406c and 1406d is 1/2 of the length of one side of the first encoding unit 1400, May be a depth of D + 1 that is one depth lower than D, which is the depth of the first encoding unit 1400.

According to an exemplary embodiment, the image decoding apparatus 2080 divides the first coding unit 1410 having a height greater than the width in the horizontal direction according to the information about the division mode, and generates a plurality of

second coding units

1412a and 1412b , 1414a, 1414b, and 1414c. According to an embodiment, the image decoding apparatus 2080 divides the first encoding unit 1420 having a shape whose length is greater than the height, in the vertical direction according to the information on the division mode, and generates a plurality of

second encoding units

1422a and 1422b , 1424a, 1424b, 1424c.

1412b, 1414a, 1414b, 1414c. 1422a, 1422b, 1414c, 1414b, 1414c, 1414b, 1414c, 1414b, 1414c, 1424a, 1424b, 1424c can be determined in depth based on the length of the long side. For example, since the length of one side of the square-shaped

second encoding units

1412a and 1412b is 1/2 times the length of one side of the non-square first encoding unit 1410 whose height is longer than the width, The depth of the

second encoding units

1412a and 1412b of the form is D + 1 which is one depth lower than the depth D of the first encoding unit 1410 of the non-square form.

Furthermore, the image decoding apparatus 2080 can divide the non-square first encoding unit 1410 into odd number of

second encoding units

1414a, 1414b and 1414c based on the information on the split mode mode. The odd number of

second encoding units

1414a, 1414b and 1414c may include non-square

second encoding units

1414a and 1414c and a square second encoding unit 1414b. In this case, the length of the long sides of the non-square type

second encoding units

1414a and 1414c and the length of one side of the second encoding unit 1414b in the square form are set to 1/10 of the length of one side of the first encoding unit 1410, The depth of the

second encoding units

1414a, 1414b, and 1414c may be a depth of D + 1 which is one depth lower than D, which is the depth of the first encoding unit 1410. [ The image decoding apparatus 2080 is connected to the first encoding unit 1420 in the form of a non-square shape whose width is longer than the height in a manner corresponding to the scheme for determining the depths of the encoding units associated with the first encoding unit 1410 The depth of the encoding units can be determined.

According to one embodiment, in determining the index (PID) for the division of the divided coding units, if the odd-numbered coding units are not the same size, the image decoding apparatus 2080 may calculate the size ratio between the coding units The index can be determined based on the index. Referring to FIG. 22, the coding unit 1414b positioned at the center among the odd-numbered

coding units

1414a, 1414b, and 1414c has the same width as the

other coding units

1414a and 1414c, Lt; / RTI > 1414a and 1414c. That is, in this case, the encoding unit 1414b positioned in the middle may include two of the

other encoding units

1414a and 1414c. Therefore, if the index (PID) of the coding unit 1414b positioned at the center is 1 according to the scanning order, the coding unit 1414c positioned next to the coding unit 1414c may be three days in which the index is increased by two. That is, there may be a discontinuity in the value of the index. According to an exemplary embodiment, the image decoding apparatus 2080 may determine whether odd-numbered encoding units are not the same size based on the presence or absence of an index discontinuity for distinguishing between the divided encoding units.

According to an exemplary embodiment, the image decoding apparatus 2080 can determine whether the image is divided into a specific division form based on an index value for identifying a plurality of coding units divided and determined from the current coding unit. 22, the image decoding apparatus 2080 divides a first coding unit 1410 of a rectangular shape whose height is longer than the width to determine an even number of

coding units

1412a and 1412b or an odd number of

coding units

1414a and 1414b , And 1414c. The image decoding apparatus 2080 may use an index (PID) indicating each coding unit in order to distinguish each of the plurality of coding units. According to one embodiment, the PID may be obtained at a sample of a predetermined position of each coding unit (e.g., the upper left sample).

According to an exemplary embodiment, the image decoding apparatus 2080 may determine an encoding unit at a predetermined position among the encoding units determined by using the index for classifying the encoding unit. According to an exemplary embodiment, when the information on the split mode format for the rectangular first-type encoding unit 1410 whose height is longer than the width is divided into three encoding units, the image decoding apparatus 2080 decodes the first encoding unit 1410 can be divided into three

coding units

1414a, 1414b, 1414c. The image decoding apparatus 2080 can assign an index to each of the three

encoding units

1414a, 1414b, and 1414c. The image decoding apparatus 2080 can compare the indexes of the respective coding units in order to determine the middle coding unit among the coding units divided into odd numbers. The image decoding apparatus 2080 encodes the encoding unit 1414b having an index corresponding to the middle value among the indices based on the indexes of the encoding units by encoding the middle position among the encoding units determined by dividing the first encoding unit 1410 Can be determined as a unit. According to an exemplary embodiment, the image decoding apparatus 2080 may determine an index based on a size ratio between coding units when the coding units are not the same size in determining the index for dividing the divided coding units . 22, the coding unit 1414b generated by dividing the first coding unit 1410 is divided into

coding units

1414a and 1414c having the same width as the

other coding units

1414a and 1414c but different in height Can be double the height. In this case, if the index (PID) of the coding unit 1414b positioned at the center is 1, the coding unit 1414c located next to the coding unit 1414c may be three days in which the index is increased by two. In this case, when the index increases uniformly and the incremental width changes, the image decoding apparatus 2080 may determine that the image is divided into a plurality of encoding units including encoding units having different sizes from other encoding units. When the information on the divisional mode is divided into odd number of encoding units, the image decoding apparatus 2080 decodes the encoding unit (for example, the middle encoding unit) at a predetermined position among the odd number of encoding units The current encoding unit can be divided into different sizes. In this case, the image decoding apparatus 2080 can determine an encoding unit having a different size by using an index (PID) for the encoding unit. However, the index and the size or position of the encoding unit at a predetermined position to be determined are specific for explaining an embodiment, and thus should not be construed to be limited thereto, and various indexes, positions and sizes of encoding units can be used Should be interpreted.

According to an exemplary embodiment, the image decoding apparatus 2080 may use a predetermined data unit in which recursive division of an encoding unit starts.

According to an embodiment, a predetermined data unit may be defined as a unit of data in which an encoding unit starts to be recursively segmented using at least one of block type information and information on a division mode mode. That is, it may correspond to a coding unit of the highest depth used in the process of determining a plurality of coding units for dividing the current picture. Hereinafter, such a predetermined data unit is referred to as a reference data unit for convenience of explanation.

According to one embodiment, the reference data unit may represent a predetermined size and shape. According to one embodiment, the reference encoding unit may comprise samples of MxN. Here, M and N may be equal to each other, or may be an integer represented by a multiplier of 2. That is, the reference data unit may represent a square or a non-square shape, and may be divided into an integer number of encoding units.

According to an exemplary embodiment, the image decoding apparatus 2080 may divide the current picture into a plurality of reference data units. According to an exemplary embodiment, the image decoding apparatus 2080 may divide a plurality of reference data units for dividing a current picture into pieces using information on a division mode mode for each reference data unit. The segmentation process of the reference data unit may correspond to the segmentation process using a quad-tree structure.

According to an exemplary embodiment, the image decoding apparatus 2080 can determine in advance the minimum size that the reference data unit included in the current picture can have. Accordingly, the image decoding apparatus 2080 can determine reference data units of various sizes having a size of a minimum size or more, and use at least one of the block type information and the division mode mode information based on the determined reference data unit The encoding unit can be determined.

Referring to FIG. 23, the image decoding apparatus 2080 can use a square-shaped reference encoding unit 1500 or a non-square-shaped reference encoding unit 1502. According to an exemplary embodiment, the type and size of the reference encoding unit may include various data units (e.g., a sequence, a picture, a slice, a slice segment a slice segment, a maximum encoding unit, and the like).

According to an exemplary embodiment, the entropy decoding unit 2055 of the image decoding apparatus 2080 may obtain at least one of the information on the type of the reference encoding unit and the size of the reference encoding unit from the bitstream for each of the various data units . The process of determining at least one encoding unit included in the reference type encoding unit 1500 is described in detail in the process of dividing the current encoding unit 300 of FIG. 11, and the process of dividing the non- ) Is determined through the process of dividing the

current encoding unit

400 or 450 of FIG. 12, so that a detailed description thereof will be omitted.

In order to determine the size and type of the reference encoding unit according to a predetermined data unit predetermined based on a predetermined condition, the image decoding apparatus 2080 may include an index for identifying the size and type of the reference encoding unit Can be used. That is, the entropy decoding unit 2055 decodes a predetermined condition (for example, data having a size smaller than a slice) among the various data units (e.g., a sequence, a picture, a slice, a slice segment, Unit), it is possible to obtain only an index for identification of the size and type of the reference encoding unit for each slice, slice segment, maximum encoding unit, and the like. The image decoding apparatus 2080 can determine the size and type of the reference data unit for each data unit that satisfies the predetermined condition by using the index. When the information on the type of the reference encoding unit and the information on the size of the reference encoding unit are obtained from the bitstream for each relatively small data unit and used, the use efficiency of the bitstream may not be good. Therefore, Information on the size of the reference encoding unit and information on the size of the reference encoding unit can be acquired and used. In this case, at least one of the size and the type of the reference encoding unit corresponding to the index indicating the size and type of the reference encoding unit may be predetermined. That is, the image decoding apparatus 2080 selects at least one of a size and a type of a predetermined reference encoding unit according to an index, thereby obtaining at least one of a size and a type of a reference encoding unit included in a data unit serving as a reference for obtaining an index You can decide.

According to an exemplary embodiment, the image decoding apparatus 2080 may use at least one reference encoding unit included in one maximum encoding unit. That is, the maximum encoding unit for dividing an image may include at least one reference encoding unit, and the encoding unit may be determined through a recursive division process of each reference encoding unit. According to an exemplary embodiment, at least one of the width and the height of the maximum encoding unit may correspond to at least one integer multiple of the width and height of the reference encoding unit. According to an exemplary embodiment, the size of the reference encoding unit may be a size obtained by dividing the maximum encoding unit n times according to a quadtree structure. In other words, the image decoding apparatus 2080 can determine the reference encoding unit by dividing the maximum encoding unit n times according to the quad tree structure, and can calculate the reference encoding unit as block type information and information on the split mode Based on at least one of them.

FIG. 24 shows a processing block serving as a reference for determining a determination order of reference encoding units included in the picture 1600 according to an embodiment.

According to one embodiment, the image decoding apparatus 2080 can determine at least one processing block that divides a picture. The processing block is a data unit including at least one reference encoding unit for dividing an image, and at least one reference encoding unit included in the processing block may be determined in a specific order. That is, the order of determination of at least one reference encoding unit determined in each processing block may correspond to one of various kinds of order in which the reference encoding unit can be determined, and the reference encoding unit determination order determined in each processing block May be different for each processing block. The order of determination of the reference encoding unit determined for each processing block is a raster scan, a Z scan, an N scan, an up-right diagonal scan, a horizontal scan a horizontal scan, and a vertical scan. However, the order that can be determined should not be limited to the scan orders.

According to an exemplary embodiment, the image decoding apparatus 2080 may obtain information on the size of the processing block to determine the size of the at least one processing block included in the image. The image decoding apparatus 2080 may obtain information on the size of the processing block from the bitstream to determine the size of the at least one processing block included in the image. The size of such a processing block may be a predetermined size of a data unit represented by information on the size of the processing block.

According to an exemplary embodiment, the entropy decoding unit 2055 of the image decoding apparatus 2080 can obtain information on the size of the processing block from the bitstream for each specific data unit. For example, information on the size of a processing block can be obtained from a bitstream in units of data such as an image, a sequence, a picture, a slice, a slice segment, and the like. That is, the entropy decoding unit 2055 can obtain information on the size of the processing block from the bitstream for each of the plurality of data units, and the image decoding apparatus 2080 divides the picture using the information on the size of the obtained processing block And the size of the processing block may be an integer multiple of the reference encoding unit.

According to an embodiment, the image decoding apparatus 2080 can determine the sizes of the processing blocks 1602 and 1612 included in the picture 1600. [ For example, the image decoding apparatus 2080 can determine the size of the processing block based on information on the size of the processing block obtained from the bitstream. 24, the image decoding apparatus 2080 decodes the horizontal size of the processing blocks 1602 and 1612 by four times the horizontal size of the reference encoding unit, four times the vertical size of the reference encoding unit, You can decide. The image decoding apparatus 2080 can determine an order in which at least one reference encoding unit is determined in at least one processing block.

According to one embodiment, the video decoding apparatus 2080 can determine each

processing block

1602, 1612 included in the picture 1600 based on the size of the processing block, and can include in the processing blocks 1602, 1612 The determination order of at least one reference encoding unit is determined. The determination of the reference encoding unit may include determining the size of the reference encoding unit according to an embodiment.

According to an exemplary embodiment, the image decoding apparatus 2080 may obtain information on a determination order of at least one reference encoding unit included in at least one processing block from a bitstream, So that the order in which at least one reference encoding unit is determined can be determined. The information on the decision order can be defined in the order or direction in which the reference encoding units are determined in the processing block. That is, the order in which the reference encoding units are determined may be independently determined for each processing block.

According to an exemplary embodiment, the image decoding apparatus 2080 may obtain information on a determination order of a reference encoding unit from a bit stream for each specific data unit. For example, the entropy decoding unit 2055 can obtain information on the determination order of the reference encoding unit from a bitstream for each data unit such as an image, a sequence, a picture, a slice, a slice segment, and a processing block. Since the information on the determination order of the reference encoding unit indicates the reference encoding unit determination order in the processing block, the information on the determination order can be obtained for each specific data unit including an integer number of processing blocks.

The image decoding apparatus 2080 may determine at least one reference encoding unit based on the determined order according to an embodiment.

According to an embodiment, the entropy decoding unit 2055 can obtain information on the reference encoding unit determination order from the bitstream as information related to the processing blocks 1602 and 1612, and the video decoding apparatus 2080 can obtain the information It is possible to determine the order of determining at least one reference encoding unit included in the

blocks

1602 and 1612 and determine at least one reference encoding unit included in the picture 1600 according to the determination order of the encoding units. Referring to FIG. 24, the video decoding apparatus 2080 can determine the

determination order

1604 and 1614 of at least one reference encoding unit associated with each of the processing blocks 1602 and 1612. For example, when information on the order of determination of the reference encoding unit is obtained for each processing block, the reference encoding unit determination order associated with each

processing block

1602, 1612 may be different for each processing block. If the reference encoding unit determination order 1604 related to the processing block 1602 is a raster scan order, the reference encoding unit included in the processing block 1602 can be determined according to the raster scan order. On the other hand, when the reference encoding unit determination order 1614 related to the other processing block 1612 is a reverse order of the raster scan order, the reference encoding unit included in the processing block 1612 can be determined according to the reverse order of the raster scan order.

The image decoding apparatus 2080 may decode the determined at least one reference encoding unit according to an embodiment. The image decoding apparatus 2080 can decode an image based on the reference encoding unit determined through the above-described embodiment. The method of decoding the reference encoding unit may include various methods of decoding the image.

According to an exemplary embodiment, the image decoding apparatus 2080 may obtain block type information indicating a type of a current encoding unit or information on a split mode mode indicating a method of dividing a current encoding unit from a bitstream. Information about the block type information or the split mode mode may be included in a bitstream related to various data units. For example, the video decoding apparatus 2080 includes a sequence parameter set, a picture parameter set, a video parameter set, a slice header, a slice segment header slice block type information included in the segment header or information on the split mode mode can be used. Further, the image decoding apparatus 2080 can acquire and use a syntax element corresponding to information on the maximum encoding unit, the reference encoding unit, the block type information from the bit stream, or the split mode mode for each processing block from the bit stream.

Various embodiments have been described above. It will be understood by those skilled in the art that the present disclosure may be embodied in various forms without departing from the essential characteristics of the present disclosure. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present disclosure is set forth in the appended claims rather than the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present disclosure.

Meanwhile, the above-described embodiments of the present disclosure can be embodied in a general-purpose digital computer that can be created as a program that can be executed by a computer and operates the program using a computer-readable recording medium. The computer readable recording medium includes a storage medium such as a magnetic storage medium (e.g., ROM, floppy disk, hard disk, etc.), optical reading medium (e.g., CD ROM, DVD, etc.).

Claims

Obtaining prediction information of blocks adjacent to an inside of an outline of a reference image when the current block refers to an area outside the outline of the reference image in motion reference;

Determining reference samples for predicting samples located outside the outline of the reference image using prediction information of a block adjacent to the outline; And

And determining samples located outside the outline of the reference image using the reference samples.

/ RTI >
The method according to claim 1,

Wherein the prediction information is inter-prediction information of a block adjacent to the inside of the outline, and the inter-prediction information includes at least one of a reference picture list, a reference index, and a motion vector.
3. The method of claim 2,

Wherein when the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the areas of the areas indicated by the motion vectors of the L1 reference list, The predictive information corresponding to the motion vector of the L0 reference list and the predictive information corresponding to the motion vector of the L1 reference list are used for a region of a smaller size among the neighboring regions, linearly determines the reference samples.
3. The method of claim 2,

When the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the motion vector of the L1 reference list are shifted in the outward direction of the area indicated by the first motion vector Wherein the reference samples are determined using prediction information excluding prediction information corresponding to the first motion vector when the neighboring region is outside the image.
3. The method of claim 2,

When the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the motion vector of the L1 reference list are shifted in the outward direction of the area indicated by the first motion vector Wherein the reference samples are generated using samples adjacent to an inside of an outline of the reference image when the neighboring region is outside the image.
The method according to claim 1,

Wherein the predictive information is intra mode information of a block adjacent to the inside of the outline and the reference samples are determined from samples in the reference image according to the intra mode information.
The method according to claim 1,

When the reference image is one of a plurality of images combined according to a 360-degree image format, if prediction information of a block adjacent to an inside of an outline of the reference image exists, And generates sample values of an area outside the outline.
Obtaining prediction information of blocks adjacent to an inside of an outline of a reference image when the current block refers to an area outside the outline of the reference image in motion reference;

Determining reference samples for predicting samples located outside the outline of the reference image using prediction information of a block adjacent to the outline; And

And determining samples located outside the outline of the reference image using the reference samples.

Video decoding method.
9. The method of claim 8,

Wherein the prediction information is inter-prediction information of a block adjacent to the inside of the outline, and the inter-prediction information includes at least one of a reference picture list, a reference index, and a motion vector.
10. The method of claim 9,

Wherein when the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the areas of the areas indicated by the motion vectors of the L1 reference list, The predictive information corresponding to the motion vector of the L0 reference list and the predictive information corresponding to the motion vector of the L1 reference list are used for a region of a smaller size among the neighboring regions, linearly determines the reference samples.
10. The method of claim 9,

When the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the motion vector of the L1 reference list are shifted in the outward direction of the area indicated by the first motion vector Wherein the reference samples are determined using prediction information excluding prediction information corresponding to the first motion vector when the neighboring region is outside the image.
10. The method of claim 9,

When the reference picture list of the inter prediction information indicates the L0 reference list and the L1 reference list, the motion vector of the L0 reference list and the motion vector of the L1 reference list are shifted in the outward direction of the area indicated by the first motion vector Wherein the reference samples are generated using samples adjacent to an inside of an outline of the reference image when the neighboring region is outside the image.
9. The method of claim 8,

Wherein the predictive information is intra mode information of a block adjacent to the inside of the outline, and determines the reference samples from the samples in the reference image according to the intra mode information.
9. The method of claim 8,

If the reference image is one of a plurality of images combined according to the 360-degree image format, if prediction information of a block of the reference image exists, reference samples indicated by the prediction information are used, &Lt; / RTI >
A prediction information acquiring unit for acquiring prediction information of blocks adjacent to an inside of an outline of a reference image when a current block refers to an out-of-frame area of the reference image in motion reference;

A reference sample determining unit for determining reference samples for predicting samples located outside the outline of the reference image using prediction information of a block adjacent to the inside of the outline; And

And an outer sample determining unit for determining a sample located outside the outline of the reference image using the reference samples.

Video decoding apparatus.