KR20180107762A - Method and apparatus for prediction based on block shape - Google Patents

Abstract

The present invention relates to a video decoding method, a decoding apparatus, an encoding method, and an encoding apparatus. In encoding and decoding a video, a plurality of divided blocks is generated by dividing a target block. A prediction mode is derived for at least some of a plurality of divided blocks. Predictions for the plurality of divided blocks can be performed based on the derived prediction mode. In performing the predictions on the divided blocks, information related to the target block can be used. Information related to another previously-predicted divided block of the divided block can be used.

Description

TECHNICAL FIELD [0001] The present invention relates to a method and apparatus for predicting a block shape,

The embodiments described below relate to a video decoding method, a decoding apparatus, a coding method, and an encoding apparatus, and more particularly, to a method and apparatus for performing prediction based on the block type in encoding and decoding video.

With the continuous development of the information and telecommunication industry, broadcasting service with HD (High Definition) resolution spread worldwide. With this proliferation, many users become accustomed to high resolution and high quality images and / or video.

In order to meet the users' demand for high image quality, many organizations are spurring development on next generation image devices. In addition to High Definition TV (HDTV) and Full HD (FHD) TVs, users' interest in ultra high definition (UHD) TVs with more than four times the resolution of FHD TVs As the interest increases, there is a need for image encoding / decoding techniques for images with higher resolution and image quality.

An apparatus and method for encoding / decoding an image includes an inter prediction technique, an intra prediction technique, and an entropy coding technique to perform encoding / decoding on high resolution and high image quality images Can be used. The inter prediction technique may be a technique of predicting a value of a pixel included in a current picture using temporally previous pictures and / or temporally subsequent pictures. The intra prediction technique may be a technique of predicting a value of a pixel included in a current picture using information of a pixel in the current picture. The entropy coding technique may be a technique of allocating a short code to a symbol having a high appearance frequency and allocating a long code to a symbol having a low appearance frequency.

Various prediction methods have been developed to improve the efficiency and accuracy of intra prediction and / or inter prediction. For example, a block may be partitioned for efficient prediction, and a prediction may be performed for each of the blocks generated by partitioning. The efficiency of prediction can be greatly changed depending on whether or not the block is divided.

One embodiment can provide a coding apparatus, a coding method, a decoding apparatus, and a decoding method for dividing a block based on a size and / or type of a block and deriving a prediction mode for the divided blocks.

One embodiment of the present invention can provide an encoding apparatus, an encoding method, a decoding apparatus, and a decoding method for performing prediction on a divided block according to an induced prediction mode.

A method comprising: generating, on a side, a plurality of divided blocks by dividing an object block; Deriving a prediction mode for at least a portion of the plurality of divided blocks; And performing predictions on the plurality of divided blocks based on the derived prediction mode.

Generating a plurality of divided blocks by dividing a target block in another side; Deriving a prediction mode for at least a portion of the plurality of divided blocks; And performing predictions on the plurality of divided blocks based on the derived prediction mode.

Whether or not the target block is divided may be determined based on information related to the target block.

Whether or not the target block is partitioned and the type of the partition may be determined based on the block partition indicator.

The target block may be divided based on the size of the target block.

The target block may be divided based on the type of the target block.

A prediction mode may be derived for a divided block specified among the plurality of divided blocks.

The specified divided block may be a block of a specified one of the plurality of divided blocks.

A prediction mode derived for the specified divided block may be used for the remaining blocks excluding the specified divided block among the plurality of divided blocks.

A prediction mode determined by a combination of a prediction mode derived for the specified divided block and another prediction mode may be used for the remaining blocks excluding the specified divided block among the plurality of divided blocks.

The most probable mode (MPM) list may be used in the derivation of the prediction mode.

The MPM list may be plural.

The MPM candidate modes of the plurality of MPM lists may not overlap with each other.

The MPM list can be configured for a specified unit.

The specified unit may be the target block.

The MPM lists for the plurality of divided blocks may be configured based on one or more reference blocks of the target block.

A prediction mode derived for a first one of the plurality of divided blocks in prediction for a second one of the plurality of divided blocks may be used.

The reconstructed pixels of the first block may be used as reference samples of the prediction for the second block.

The reference samples used for the predictions of the plurality of divided blocks may be reconstructed pixels adjacent to the target block.

The prediction mode may be derived for the lowermost block or the rightmost block among the plurality of divided blocks.

In the prediction for the lowermost block, reconstructed pixels adjacent to the top of the target block may be used as reference pixels.

The predictions of the plurality of divided blocks may be performed according to a predetermined order.

The predetermined order is an order from the lowermost block to the uppermost block, the order from the rightmost block to the leftmost block, the lowest block is selected first, then the next block from the uppermost block, Blocks or the order in which the rightmost block is selected first and then the rightmost to the second block from the leftmost block sequentially.

On another side, deriving a prediction mode; Generating a plurality of divided blocks by dividing a target block; And performing predictions on the plurality of divided blocks based on the derived prediction mode.

A coding method, a decoding device, and a decoding method for dividing a block based on a size and / or type of a block and deriving a prediction mode for the divided blocks are provided.

There is provided an encoding apparatus, an encoding method, a decoding apparatus, and a decoding method for performing prediction on a divided block according to an induced prediction mode.

1 is a block diagram illustrating a configuration of an encoding apparatus to which the present invention is applied.
2 is a block diagram illustrating a configuration of a decoding apparatus to which the present invention is applied.
3 is a diagram schematically showing a division structure of an image when coding and decoding an image.
Fig. 4 is a diagram showing a form of a prediction unit (PU) that a coding unit (CU) can include.
5 is a diagram showing a form of a conversion unit (TU) which can be included in a coding unit (CU).
6 is a diagram for explaining an embodiment of an intra prediction process.
7 is a view for explaining the positions of reference samples used in the intra prediction process.
8 is a diagram for explaining an embodiment of the inter prediction process.
Figure 9 shows spatial candidates according to an example.
FIG. 10 shows an addition sequence of motion information of spatial candidates to a merge list according to an example.
Figure 11 illustrates the process of transform and quantization according to an example.
12 is a structural diagram of an encoding apparatus according to an embodiment.
13 is a structural diagram of a decoding apparatus according to an embodiment.
14 is a flowchart of a prediction method according to an embodiment.
15 is a flowchart of a block partitioning method according to an embodiment.
16 shows an 8x4 target block according to an example.
17 shows divided blocks of 4x4 size according to an example.
18 shows a 4x16 target block according to an example.
FIG. 19 shows divided blocks of 8x4 size according to an example.
FIG. 20 shows divided blocks of 4x4 size according to an example.
21 is a flowchart of a method of deriving a prediction mode for a divided block according to an example.
Figure 22 shows a prediction for a partitioned block according to an example.
23 shows a prediction for a partitioned block using a reconstructed block of a partitioned block according to an example.
Figure 24 shows a prediction for a partitioned block using reference pixels outside the partitioned block according to an example.
25 shows prediction of four divided blocks according to an example.
FIG. 26 shows a prediction for the first block after the prediction for the fourth block according to an example is performed.
FIG. 27 shows a prediction for a second block according to an example.
FIG. 28 shows a prediction for the third block according to the work.
29 is a flowchart of a prediction method according to an embodiment.
30 shows the derivation of a prediction mode for a target block according to an example.
31 is a flowchart of a prediction method of a target block and a bitstream generation method according to an embodiment.
32 is a flowchart of a prediction method of a target block using a bitstream according to an embodiment.
FIG. 33 shows the division of an upper block according to an example.
34 shows the partitioning of an object block according to an example.
35 is a signal flow diagram illustrating a method of encoding and decoding an image according to an embodiment.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The following detailed description of exemplary embodiments refers to the accompanying drawings, which illustrate, by way of illustration, specific embodiments. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments. It should be understood that the various embodiments are different, but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with one embodiment. It is also to be understood that the location or arrangement of the individual components within each disclosed embodiment may be varied without departing from the spirit and scope of the embodiments. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the exemplary embodiments is to be limited only by the appended claims, along with the full scope of equivalents to which such claims are entitled, if properly explained.

In the drawings, like reference numerals refer to the same or similar functions throughout the several views. The shape and size of the elements in the figures may be exaggerated for clarity.

The terms first, second, etc. in the present invention may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

When it is mentioned that a component is "connected" or "connected" to another component, the two components may be directly connected or connected to each other, It is to be understood that other components may be present in the middle of the components. When a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that no other component is present in the middle of the two components.

The components shown in the embodiments of the present invention are shown independently to represent different characteristic functions, and do not mean that each component is composed of separate hardware or one software constituent unit. That is, each component is listed as a separate component for convenience of explanation. At least two components of each component are combined to form one component, or one component is divided into a plurality of components, And the integrated embodiments and the separate embodiments of each of these components are also included in the scope of the present invention unless they depart from the essence of the present invention.

Also, in the exemplary embodiments, the description of "comprising" a specific configuration does not exclude a configuration other than the specific configuration, and the additional configuration is not limited to the implementation of the exemplary embodiments or the technical idea of the exemplary embodiments. Range. ≪ / RTI >

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present invention, the term "comprises" or "having ", etc. is intended to specify that there is a feature, number, step, operation, element, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. In other words, the description of "including" a specific configuration in the present invention does not exclude a configuration other than the configuration, and it is also possible that additional configurations can be included in the scope of the present invention or the scope of the present invention.

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 embodiments. In the following description of the embodiments, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present disclosure rather unclear. The same reference numerals are used for the same constituent elements in the drawings, and redundant description of the same constituent elements is omitted.

Hereinafter, an image may denote a picture constituting a video, or may represent a video itself. For example, "encoding and / or decoding of an image" may mean "encoding and / or decoding of video ", which means" encoding and / or decoding of one of the images constituting a video " It is possible.

Hereinafter, the terms "video" and "motion picture" may be used interchangeably and may be used interchangeably.

Hereinafter, the target image may be a coding target image to be coded and / or a decoding target image to be decoded. The target image may be an input image input to the encoding device or an input image input to the decoding device.

In the following, the terms "image", "picture", "frame" and "screen" may be used interchangeably and may be used interchangeably.

Hereinafter, the target block may be a current block to be coded and / or a current block to be decoded. Also, the target block may be the current block that is the current encoding and / or decoding target. For example, the terms "object block" and "current block" may be used interchangeably and may be used interchangeably.

In the following, the terms "block" and "unit" may be used interchangeably and may be used interchangeably. Or "block" may represent a particular unit.

In the following, the terms " region "and" segment "

Hereinafter, a specific signal may be a signal indicating a specific block. For example, an original signal may be a signal representing a target block. The prediction signal may be a signal representing a prediction block. The residual signal may be a signal representing a residual block.

In embodiments, each of the specified information, data, flags and elements, attributes, etc. may have a value. The value "0" of information, data, flags and element, attribute, etc. may represent a logical false or a first predefined value. That is to say, the values "0 ", False, Logical False, and First Default values can be used interchangeably. The value "1" of information, data, flags and elements, attributes, etc. may represent a logical true or a second predefined value. That is to say, the values "1 ", " true ", " logical "

When a variable such as i or j is used to represent a row, column or index, the value of i may be an integer greater than or equal to 0 and may be an integer greater than or equal to one. In other words, in the embodiments, rows, columns, indexes, etc. may be counted from 0 and counted from 1.

Hereinafter, terms used in the embodiments will be described.

Encoder: An apparatus that performs encoding.

Decoder: A device that performs decoding.

Unit: A unit may represent a unit of encoding and decoding of an image. The terms "unit" and "block" may be used interchangeably and may be used interchangeably.

- The unit may be an MxN array of samples. M and N may be positive integers, respectively. A unit can often refer to an array of two-dimensional samples.

- In coding and decoding of an image, a unit may be an area generated by the division of one image. One image may be divided into a plurality of units. Alternatively, a unit may mean the divided portion when one image is divided into subdivided portions and when encoding or decoding is performed on the subdivided portions.

- In the encoding and decoding of images, predetermined processing on the unit may be performed depending on the type of unit.

- Depending on the function, the unit type may be a Macro Unit, a Coding Unit (CU), a Prediction Unit (PU), a Residual Unit and a Transform Unit (TU) . ≪ / RTI > Alternatively, depending on the function, the unit may include a block, a macroblock, a Coding Tree Unit (CTU), a Coding Tree Block, a Coding Unit, a Coding Block, A prediction unit, a prediction block, a residual unit, a residual block, a transform unit, and a transform block.

- unit may refer to information comprising a luma component block and its corresponding chroma component block, and a syntax element for each block, to distinguish it from a block.

- The size and shape of the unit may vary. In addition, the unit may have various sizes and shapes. In particular, the shape of the unit may include not only squares but also geometric figures that can be expressed in two dimensions, such as rectangles, trapezoids, triangles, and pentagons.

Also, the unit information may include at least one of a unit type indicating a coding unit, a prediction unit, a residual unit, a conversion unit, etc., a unit size, a unit depth, a unit encoding and decoding order,

- one unit may be further subdivided into smaller units with a smaller size than the unit.

Unit depth: Unit depth can mean the degree of division of the unit. Unit depth can also indicate the level at which a unit is present when the unit is represented in a tree structure.

The unit division information may include a unit depth with respect to the depth of the unit. The unit depth may indicate the number and / or the number of times the unit is divided.

In the tree structure, the depth of the root node is the shallowest and the depth of the leaf node is the deepest.

- A unit may be hierarchically divided into a plurality of subunits with depth information based on a tree structure. That is to say, the unit and the lower unit generated by the division of the unit can correspond to the node and the child node of the node, respectively. Each divided subunit may have a unit depth. Since the unit depth indicates the number and / or degree of division of the unit, the division information of the lower unit may include information on the size of the lower unit.

- In a tree structure, the top node may correspond to the first unit that has not been partitioned. The superordinate node may be referred to as a root node. Also, the uppermost node may have a minimum depth value. At this time, the uppermost node can have a level 0 depth.

- A node with a depth of level 1 can represent a unit created as the first unit is once partitioned. A node with a depth of level 2 may represent a unit created as the first unit is divided twice.

- A node with a depth of level n can represent a unit created as the first unit is divided n times.

The leaf node may be the lowest node, and may be a node that can not be further divided. The depth of the leaf node may be the maximum level. For example, the default value of the maximum level may be three.

Sample: A sample can be a base unit that makes up a block. The sample can be expressed as values from 0 to 2 ^Bd -1 depending on the bit depth (Bd).

The sample may be a pixel or a pixel value.

- In the following, the terms "pixel", "pixel" and "sample" may be used interchangeably and may be used interchangeably.

Coding Tree Unit (CTU): A CTU can be composed of one luminance component (Y) encoded tree block and two chrominance component (Cb, Cr) encoded tree blocks related to the luminance component encoded tree block have. The CTU may also include the above blocks and the syntax elements for each block of the above blocks.

Each coding tree unit may be divided using one or more division methods such as a quad tree and a binary tree to construct a lower unit such as a coding unit, a prediction unit and a conversion unit .

- The CTU can be used as a term to refer to a pixel block, which is a processing unit in the process of decoding and encoding an image, as in the segmentation of an input image.

Coding Tree Block (CTB): The coded tree block can be used as a term for designating any one of Y-coded tree block, Cb-coded tree block, and Cr-coded tree block.

Neighbor block: means a block adjacent to a target block. A block adjacent to the target block may refer to a block whose boundary is bounded to the target block or a block located within a predetermined distance from the target block. The neighboring block may mean a block adjacent to the vertex of the target block. Here, a block adjacent to a vertex of a target block may be a block vertically adjacent to a neighboring block horizontally adjacent to the target block or a block horizontally adjacent to a neighboring block vertically adjacent to the target block. A neighboring block may mean a restored neighboring block.

Prediction unit: It can mean a base unit for prediction such as intra-picture prediction, intra prediction, inter-picture compensation, intra-picture compensation, and motion compensation.

- one prediction unit may be divided into a plurality of partitions or lower prediction units having a smaller size. The plurality of partitions may also be a base unit in performing prediction or compensation. The partition generated by the division of the prediction unit may also be a prediction unit.

Prediction unit partition: Prediction unit may mean a partitioned form.

Reconstructed neighboring unit: The reconstructed neighboring unit may be a unit that has already been decoded and reconstructed around the target unit.

The reconstructed neighboring unit may be a spatial adjacent unit or a temporal adjacent unit for the target unit.

The reconstructed spatial neighboring unit may be a unit in the current picture and a unit already reconstructed through coding and / or decoding.

- the reconstructed temporal neighboring unit may be a unit in the reference image and a unit already reconstructed through coding and / or decoding. The position in the reference picture of the reconstructed temporal neighboring unit may be the same as the position in the current picture of the target unit or may correspond to the position in the current picture of the target unit.

Parameter set: A parameter set may correspond to header information among structures in a bitstream. For example, the parameter set may include a sequence parameter set, a picture parameter set, and an adaptation parameter set.

Rate-distortion optimization: An encoding apparatus uses rate-distortion optimization to provide a high coding efficiency using a combination of a coding unit size, a prediction mode, a prediction unit size, motion information, Distortion optimization can be used.

The rate-distortion optimization scheme can calculate the rate-distortion cost of each combination to select the optimal combination from among the combinations above. The rate-distortion cost can be calculated using Equation 1 below. In general, the combination in which the rate-distortion cost is minimized can be selected as the optimum combination in the rate-distortion optimization method.

[Equation 1]

- D can indicate distortion. D may be the mean square error of the difference values between the original transform coefficients and the reconstructed transform coefficients in the transform unit.

- R can represent the rate. R can represent the bit rate using related context information.

- [lambda] can represent a Lagrangian multiplier. R may include coding parameter information such as a prediction mode, motion information, and coded block flag, as well as bits generated by coding the transform coefficients.

- The encoder may perform inter prediction and / or intra prediction, conversion, quantization, entropy coding, inverse quantization, inverse transform, etc. to calculate the correct D and R. These processes can greatly increase the complexity in the encoding apparatus.

Bitstream: A bitstream may be a bit string containing encoded image information.

Parameter set: A parameter set may correspond to header information among structures in a bitstream.

At least one of a Video Parameter Set (VPS), a Sequence Parameter Set (SPS), a Picture Parameter Set (PPS), and an Adaptation Parameter Set (APS) . ≪ / RTI > The parameter set may also include information of a slice header and information of a tile header.

Parsing: Parsing may entropy-decode the bitstream to determine the value of a syntax element. Or, parsing may mean entropy decoding itself.

Symbol: may include at least one of a syntax element, a coding parameter, and a transform coefficient of a coding target unit and / or a target unit to be decoded. In addition, the symbol may mean a target of entropy encoding or a result of entropy decoding.

Reference picture: A reference picture may refer to an image that a unit refers to for inter prediction or motion compensation. Alternatively, the reference picture may be an image including a reference unit referred to by the target unit for inter prediction or motion compensation.

Hereinafter, the terms "reference picture" and "reference picture" may be used interchangeably and may be used interchangeably.

Reference picture list: A reference picture list may be a list including one or more reference pictures used for inter-prediction or motion compensation.

The types of the reference picture list include a list combination (LC), a list 0 (L0), a list 1 (L1), a list 2 (L2), and a list 3 ) And the like.

- One or more reference picture lists may be used for inter prediction.

Inter Prediction Indicator: An inter prediction indicator may indicate the direction of inter prediction of a target unit. The inter prediction may be one of a unidirectional prediction and a bidirectional prediction. Alternatively, the inter prediction indicator may indicate the number of reference images used when generating the prediction unit of the target unit. Alternatively, the inter prediction indicator may mean the number of prediction blocks used for inter prediction or motion compensation for the target unit.

Reference picture index: The reference picture index may be an index indicating a specific reference picture in the reference picture list.

Motion Vector (MV): A motion vector may be a two-dimensional vector used in inter prediction or motion compensation. The motion vector may mean an offset between the video to be encoded / decoded and the reference video.

- For example, MV can be expressed in the form (mv _x , mv _y ). mv _x may represent a horizontal component, and mv _y may represent a vertical component.

Search range: The search area may be a two-dimensional area where an MV search is performed during inter prediction. For example, the size of the search area may be MxN. M and N may be positive integers, respectively.

Motion vector candidate: A motion vector candidate may mean a motion vector of a block, which is a prediction candidate or a prediction candidate, when a motion vector is predicted.

- The motion vector candidate may be included in the motion vector candidate list.

Motion Vector Candidate List: A motion vector candidate list may refer to a list constructed using one or more motion vector candidates.

Motion vector candidate index: The motion vector candidate index may indicate an indicator indicating a motion vector candidate in a motion vector candidate list. Alternatively, the motion vector candidate index may be an index of a motion vector predictor.

Motion information: Motion information includes motion picture information, reference picture list information, reference pictures, motion vector candidates, motion vector candidate indexes, merge candidates, and merge indices, as well as motion vectors, reference picture indexes and inter prediction indicators Quot; and " information "

Merge candidate list: A merge candidate list can mean a list constructed using merge candidates.

Merge candidates: Spatial merge candidates, temporal merge candidates, combined merge candidates, combined bi-prediction merge candidates, and zero merge candidates. The merge candidate may include motion information such as an inter prediction indicator, a reference picture index for each list, and a motion vector.

The merge index: The merge index can be an indicator that points to a merge candidate in the merge candidate list.

The merge index may indicate a reconstructed unit spatially adjacent to the target unit and a reconstructed unit that derives the merge candidate out of the reconstructed units temporally adjacent to the target unit.

The merge index may indicate at least one of the motion information of the merge candidate.

Transform unit: The transform unit may be a base unit in residual signal coding and / or residual signal decoding such as transform, inverse transform, quantization, inverse quantization, transform coefficient coding and transform coefficient decoding. One conversion unit can be divided into a plurality of conversion units of a smaller size.

Scaling: Scaling can refer to the process of multiplying the transform coefficient level by an argument.

As a result of scaling to the transform coefficient level, a transform coefficient can be generated. Scaling may also be referred to as dequantization.

Quantization Parameter (QP): The quantization parameter may refer to a value used when generating a transform coefficient level for a transform coefficient in quantization. Or a value used when generating a transform coefficient by scaling the transform coefficient level in the inverse quantization. Alternatively, the quantization parameter may be a value mapped to a quantization step size.

Delta quantization parameter: A delta quantization parameter means a predicted quantization parameter and a differential value of a quantization parameter of a unit to be encoded / decoded.

Scan: A scan may mean a method of arranging the order of coefficients within a unit, block, or matrix. For example, arranging a two-dimensional array in a one-dimensional array form can be referred to as a scan. Alternatively, arranging the one-dimensional arrays in the form of a two-dimensional array may be referred to as a scan or an inverse scan.

Transform coefficient: The transform coefficient may be a coefficient value generated as a result of performing the transform in the encoding apparatus. Alternatively, the transform coefficient may be a coefficient value generated by performing at least one of entropy decoding and inverse quantization in the decoding apparatus.

- The quantized level or the quantized transform coefficient level to which the quantization is applied to the transform coefficient or the residual signal may also be included in the meaning of the transform coefficient.

Quantized level: The quantized level may mean a value generated by performing a quantization on a transform coefficient or a residual signal in an encoding apparatus. Alternatively, the quantized level may be a value to be subjected to inverse quantization in performing inverse quantization in the decoding apparatus.

- The quantized transform coefficient levels resulting from the transform and quantization can also be included in the meaning of the quantized levels.

Non-zero transform coefficient: A non-zero transform coefficient may mean a transform coefficient having a value other than zero or a transform coefficient level having a non-zero value. Alternatively, the non-zero transform coefficient may mean a transform coefficient whose magnitude is not zero or a transform coefficient level whose magnitude is not zero.

Quantization matrix: A quantization matrix may mean a matrix used in the quantization or inverse quantization process to improve the subjective or objective image quality of an image. The quantization matrix may also be referred to as a scaling list.

Quantization matrix coefficient: The quantization matrix coefficient may refer to each element in the quantization matrix. The quantization matrix coefficient may also be referred to as a matrix coefficient.

Default matrix: The base matrix may be a predefined quantization matrix in the encoder and decoder.

Non-default matrix: The non-default matrix may be a non-default quantization matrix in the encoder and decoder. The non-default matrix may be signaled from the encoder to the decoder.

1 is a block diagram illustrating a configuration of an encoding apparatus to which the present invention is applied.

The encoding apparatus 100 may be an encoder, a video encoding apparatus, or an image encoding apparatus. The video may include one or more images. The encoding apparatus 100 may sequentially encode one or more images of the video.

1, an encoding apparatus 100 includes an inter prediction unit 110, an intra prediction unit 120, a switch 115, a subtractor 125, a transform unit 130, a quantization unit 140, An inverse quantization unit 160, an inverse transform unit 170, an adder 175, a filter unit 180, and a reference picture buffer 190.

The encoding apparatus 100 may perform encoding of a target image using an intra mode and / or an inter mode.

In addition, the encoding apparatus 100 can generate a bitstream including encoding information through encoding of a target image, and output the generated bitstream. The generated bit stream can be stored in a computer-readable recording medium and can be streamed through a wired / wireless transmission medium.

When the intra mode is used as the prediction mode, the switch 115 can be switched to intra. When the inter mode is used as the prediction mode, the switch 115 can be switched to the inter.

The encoding apparatus 100 may generate a prediction block for the target block. Also, after the prediction block is generated, the encoding device 100 can code the residual of the target block and the prediction block.

When the prediction mode is the intra mode, the intra prediction unit 120 can use the pixels of the already coded / decoded block around the target block as a reference sample. The intra prediction unit 120 can perform spatial prediction of a target block using a reference sample and generate prediction samples of a target block through spatial prediction.

The inter prediction unit 110 may include a motion prediction unit and a motion compensation unit.

When the prediction mode is the inter mode, the motion predicting unit can search for the best matched region from the reference block in the motion estimation process, derive the motion vector for the target block and the searched region using the searched region, can do.

The reference picture may be stored in the reference picture buffer 190 and may be stored in the reference picture buffer 190 when the coding and / or decoding of the reference picture has been processed.

The motion compensation unit may generate a prediction block for a target block by performing motion compensation using a motion vector. Here, the motion vector may be a two-dimensional vector used for inter prediction. The motion vector may also indicate an offset between the target image and the reference image.

The motion prediction unit and the motion compensation unit can generate a prediction block by applying an interpolation filter to a part of the reference image when the motion vector has a non-integer value. In order to perform inter prediction or motion compensation, a method of motion prediction and motion compensation of a PU included in a CU based on a CU is called a skip mode, a merge mode, an advanced motion vector prediction (AMVP) mode and a current picture reference mode, and inter prediction or motion compensation may be performed according to each mode.

The subtracter 125 may generate a residual block which is a difference between the target block and the prediction block. The residual block may be referred to as a residual signal.

The residual signal may mean a difference between the original signal and the prediction signal. Alternatively, the residual signal may be a signal generated by transforming, quantizing, or transforming and quantizing the difference between the original signal and the prediction signal. The residual block may be a residual signal for a block unit.

The transforming unit 130 may perform a transform on the residual block to generate a transform coefficient, and output the generated transform coefficient. Here, the transform coefficient may be a coefficient value generated by performing a transform on the residual block.

When the transform skip mode is applied, the transforming unit 130 may omit the transform for the residual block.

A quantized transform coefficient level or a quantized level can be generated by applying quantization to the transform coefficients. Hereinafter, in the embodiments, the quantized transform coefficient level and the quantized level may also be referred to as a transform coefficient.

The quantization unit 140 may generate a quantized transform coefficient level or a quantized level by quantizing the transform coefficient in accordance with the quantization parameter. The quantization unit 140 may output the generated quantized transform coefficient level or the generated quantized level. At this time, the quantization unit 140 can quantize the transform coefficient using the quantization matrix.

The entropy encoding unit 150 can generate a bitstream by performing entropy encoding according to the probability distribution based on the values calculated by the quantization unit 140 and / or the coding parameter values calculated in the encoding process . The entropy encoding unit 150 may output the generated bitstream.

The entropy encoding unit 150 may perform entropy encoding on information about pixels of an image and information for decoding an image. For example, the information for decoding the image may include a syntax element or the like.

The coding parameters may be information required for coding and / or decoding. The coding parameters may include information that is encoded in the encoding apparatus 100 and transferred from the encoding apparatus 100 to the decoding apparatus, and may include information that can be inferred in the encoding or decoding process. For example, as information transmitted to the decoding apparatus, there is a syntax element.

For example, the coding parameters may include prediction modes, motion vectors, reference picture indexes, coding block patterns, presence or absence of residual signals, transform coefficients, quantized transform coefficients, quantization parameters, block sizes, ) Information, and the like. The prediction mode may indicate an intra prediction mode or an inter prediction mode.

The residual signal may represent the difference between the original signal and the prediction signal. Alternatively, the residual signal may be a signal generated by transforming the difference between the original signal and the prediction signal. Alternatively, the residual signal may be a signal generated by transforming and quantizing the difference between the original signal and the prediction signal.

When entropy coding is applied, a small number of bits can be assigned to a symbol having a high probability of occurrence, and a large number of bits can be assigned to a symbol having a low probability of occurrence. As the symbol is represented through this allocation, the size of the bit string for the symbols to be encoded can be reduced. Therefore, the compression performance of the image encoding can be improved through the entropy encoding.

In addition, the entropy encoding unit 150 may use an exponential golomb, a context-adaptive variable length coding (CAVLC), and a context-adaptive binary arithmetic coding Arithmetic Coding (CABAC), and the like can be used. For example, the entropy encoding unit 150 may perform entropy encoding using a Variable Length Coding / Code (VLC) table. For example, the entropy encoding unit 150 may derive a binarization method for a target symbol. In addition, the entropy encoding unit 150 may derive a probability model of a target symbol / bin. The entropy encoding unit 150 may perform arithmetic encoding using the derived binarization method, the probability model, and the context model.

The entropy encoding unit 150 may change the coefficients of a form of a two-dimensional block into a one-dimensional vector form through a transform coefficient scanning method to encode a transform coefficient level.

Coding parameters may include not only information (or flags, indexes, etc.) encoded in a coding apparatus such as syntax elements and signaled from a coding apparatus to a decoding apparatus, but also information derived from a coding process or a decoding process have. In addition, the coding parameters may include information required in coding or decoding an image. For example, the unit / block size, the unit / block depth, the unit / block division information, the unit / block division structure, the information indicating whether the unit / block is divided into quad- Tree-type division direction (horizontal direction or vertical direction), binary-tree type division form (symmetric division or asymmetric division), prediction method (intra-prediction or inter- ), Intra prediction mode / direction, reference sample filtering method, prediction block filtering method, prediction block boundary filtering method, filter tap of filtering, filter coefficient of filtering, inter prediction mode, motion information, motion vector, reference picture index, inter prediction Direction, inter prediction indicator, reference picture list, reference picture, motion vector predictor, motion vector prediction candidate, motion vector candidate list, merge mode. A merge candidate list, information indicating whether a skip mode is used, a type of an interpolation filter, a filter tap of an interpolation filter, a filter coefficient of an interpolation filter, a motion vector size, a motion vector expression accuracy, Information indicating whether or not to use the primary conversion, information indicating whether or not the primary conversion is used, information indicating whether the secondary conversion is used, information indicating whether or not the primary conversion index, secondary conversion index, A coded block flag, a quantization parameter, a quantization matrix, information on an intra-loop filter, information on whether or not an intra-loop filter is applied, A filter tap of an intra-loop, a shape / form of an intra-loop filter, information indicating whether a deblocking filter is applied, a deblocking filter coefficient , A deblocking filter tap, a deblocking filter strength, a deblocking filter shape / shape, information indicating whether an adaptive sample offset is applied, an adaptive sample offset value, an adaptive sample offset category, an adaptive sample offset type, Whether or not an in-loop filter is applied, an adaptive loop-in filter coefficient, an adaptive loop-in filter tap, an adaptive loop-in filter shape / form, a binarization / inverse binarization method, a contextual model, A method of determining a model, a method of updating a context model, whether to perform a regular mode, whether to perform a bypass mode, a context bin, a bypass bin, a conversion coefficient, a conversion coefficient level, , Slice identification information, slice type, slice division information, tile identification information, tile type, tile division information, picture type, bit depth, At least one value or a combined form of information on the color difference signal may be included in the coding parameter.

Signaling a flag or an index may be performed by encoding the entropy-encoded flag or the entropy-encoded index generated by performing entropy encoding on a flag or an index in a bitstream in the encoding apparatus 100 And the decryption apparatus 200 may mean to obtain a flag or an index by performing entropy decoding on an entropy-encoded flag extracted from the bitstream or an entropy-encoded index .

Since encoding is performed through inter-prediction by the encoding apparatus 100, the encoded target image can be used as a reference image for another image (s) to be processed later. Accordingly, the encoding apparatus 100 can reconstruct or decode the encoded target image again, and store the reconstructed or decoded image as a reference image in the reference picture buffer 190. [ The inverse quantization and inverse transform of the encoded object image for decoding can be processed.

The quantized level may be inversely quantized in the inverse quantization unit 160 and may be inversely transformed in the inverse transformation unit 170. [ The dequantized and / or inverse transformed coefficients may be combined with the prediction block via an adder 175. A reconstructed block may be generated by summing the dequantized and / or inverse transformed coefficients and the prediction block. Here, the dequantized and / or inverse transformed coefficient may mean a coefficient on which at least one of dequantization and inverse-transformation is performed, and may mean a reconstructed residual block.

The reconstructed block may pass through filter portion 180. The filter unit 180 may include at least one of a deblocking filter, a sample adaptive offset (SAO), and an adaptive loop filter (ALF) It can be applied to a picture. The filter unit 180 may be referred to as an in-loop filter.

The deblocking filter can remove block distortion occurring at the boundary between the blocks. To determine whether to apply a deblocking filter, it may be determined whether to apply a deblocking filter to a target block based on the number of columns or pixels (or pixels) included in the block. When a deblocking filter is applied to a target block, the applied filter may differ depending on the strength of the required deblocking filtering. In other words, a filter determined according to the strength of deblocking filtering among different filters can be applied to the target block.

SAO may add an appropriate offset to the pixel value of the pixel to compensate for coding errors. SAO can perform correction using an offset with respect to a difference between an original image and an image to which deblocking is applied, in units of pixels, for an image to which deblocking is applied. A method of dividing a pixel included in an image into a predetermined number of regions, determining an area to be offset of the divided areas, and applying an offset to the determined area may be used, and edge information of each pixel of the image may be used A method of applying the offset by considering it may be used.

ALF can perform filtering based on the comparison of the reconstructed image and the original image. After dividing the pixels included in the image into predetermined groups, a filter to be applied to the divided group can be determined, and filtering can be performed differently for each group. Information related to whether or not an adaptive loop filter is applied can be signaled per CU. , The shape of the ALF to be applied to each block and the filter coefficient may be different for each block.

The reconstructed block or reconstructed image through the filter unit 180 may be stored in the reference picture buffer 190. [ The reconstructed block through the filter unit 180 may be part of the reference picture. That is to say, the reference picture may be a reconstructed picture composed of reconstructed blocks via the filter unit 180. [ The stored reference picture can then be used for inter prediction.

2 is a block diagram illustrating a configuration of a decoding apparatus to which the present invention is applied.

The decoding apparatus 200 may be a decoder, a video decoding apparatus, or an image decoding apparatus.

2, the decoding apparatus 200 includes an entropy decoding unit 210, an inverse quantization unit 220, an inverse transform unit 230, an intra prediction unit 240, an inter prediction unit 250, an adder 255, A filter unit 260, and a reference picture buffer 270.

The decoding apparatus 200 can receive the bit stream output from the encoding apparatus 100. [ The decoding apparatus 200 can receive a bitstream stored in a computer-readable recording medium and can receive a bitstream streamed through a wired / wireless transmission medium.

The decoding apparatus 200 may perform decoding of an intra mode and / or an inter mode with respect to a bit stream. In addition, the decoding apparatus 200 can generate a reconstructed image or a decoded image through decoding, and output the reconstructed image or the decoded image.

For example, switching to an intra mode or an inter mode according to a prediction mode used for decoding may be performed by a switch. When the prediction mode used for decoding is the intra mode, the switch can be switched to intra. When the prediction mode used for decoding is the inter mode, the switch can be switched to the inter.

The decoding apparatus 200 can obtain a reconstructed residual block by decoding the input bitstream, and can generate a prediction block. Once the reconstructed residual block and prediction block are obtained, the decoding apparatus 200 can generate a reconstructed block to be decoded by adding the reconstructed residual block and the prediction block.

The entropy decoding unit 210 may generate the symbols by performing entropy decoding on the bitstream based on the probability distribution of the bitstream. The generated symbols may include symbols in the form of a quantized level. Here, the entropy decoding method may be similar to the above-described entropy encoding method. For example, the entropy decoding method may be the inverse of the above-described entropy encoding method.

The quantized coefficients may be inversely quantized in the inverse quantization unit 220. The inverse quantization unit 220 may generate inverse quantized coefficients by performing inverse quantization on the quantized coefficients. Also, the inverse quantized coefficient may be inversely transformed by the inverse transform unit 230. The inverse transform unit 230 may generate the reconstructed residual block by performing an inverse transform on the inversely quantized coefficient. As a result of performing inverse quantization and inverse transform on the quantized coefficients, reconstructed residual blocks can be generated. In this case, the inverse quantization unit 220 may apply the quantization matrix to the quantized coefficients in generating the reconstructed residual block.

When the intra mode is used, the intraprediction unit 240 can generate a prediction block by performing spatial prediction using the pixel value of the already decoded block around the target block.

The inter prediction unit 250 may include a motion compensation unit. Alternatively, the inter prediction unit 250 may be named as a motion compensation unit.

When the inter mode is used, the motion compensation unit may generate a prediction block by performing motion compensation using a motion vector and a reference image stored in the reference picture buffer 270. [

If the motion vector has a non-integer value, the motion compensation unit can apply an interpolation filter to a part of the reference image and generate a prediction block using the reference image to which the interpolation filter is applied. The motion compensation unit may determine which of the skip mode, the merge mode, the AMVP mode, and the current picture reference mode is used for the PU included in the CU based on the CU to perform motion compensation, To perform motion compensation.

The reconstructed residual block and the prediction block may be added through an adder 255. The adder 255 may generate the reconstructed block by adding the reconstructed residual block and the prediction block.

The reconstructed block may pass through filter portion 260. The filter unit 260 may apply at least one of the deblocking filter, SAO, and ALF to the reconstructed block or the reconstructed picture.

The reconstructed block through the filter unit 260 can be stored in the reference picture buffer 270. [ The reconstructed block through the filter unit 260 may be part of the reference picture. That is to say, the reference image may be an image composed of reconstructed blocks through the filter unit 260. The stored reference image can then be used for inter prediction.

3 is a diagram schematically showing a division structure of an image when coding and decoding an image.

3 schematically shows an example in which one unit is divided into a plurality of lower units.

To efficiently divide an image, a coding unit (CU) can be used in coding and decoding. A unit may be a term collectively referred to as 1) a block containing image samples and 2) a syntax element. For example, "division of a unit" may mean "division of a block corresponding to a unit ".

CU can be used as a base unit of image encoding / decoding. Also, the CU can be used as a unit to which one of the intra mode and the inter mode is applied in image encoding / decoding. That is to say, in the image coding / decoding, it is possible to determine which of intra mode and inter mode is applied to each CU.

The CU may also be a base unit for prediction, transform, quantization, inverse transform, dequantization, and encoding / decoding of transform coefficients.

Referring to FIG. 3, the image 300 can be sequentially divided into units of a Largest Coding Unit (LCU), and the divided structure of the image 300 can be determined according to the LCU. Here, the LCU can be used in the same sense as a coding tree unit (CTU).

The division of a unit may mean division of a block corresponding to the unit. The block partitioning information may include depth information about the depth of the unit. The depth information may indicate the number and / or the number of times the unit is divided. One unit may be hierarchically subdivided with depth information based on a tree structure. Each divided subunit may have depth information. The depth information may be information indicating the size of the CU. Depth information can be stored for each CU. Each CU can have depth information.

The divided structure may mean a distribution of CUs for efficiently encoding an image in the LCU 310. [ This distribution can be determined depending on whether or not to divide one CU into a plurality of CUs. The number of divided CUs may be two or more positive integers including 2, 3, 4, 8, and 16, and so on. The horizontal size and the vertical size of the CU generated by the division may be smaller than the horizontal size and the vertical size of the CU before division according to the number of CUs generated by the division.

The divided CUs can be recursively divided into a plurality of CUs in the same manner. By recursive partitioning, the size of at least one of the horizontal and vertical sizes of the partitioned CUs can be reduced compared to at least one of the horizontal and vertical sizes of the CUs before partitioning.

The partitioning of the CU can be done recursively up to a predetermined depth or a predetermined size. For example, the depth of the LCU may be zero, and the depth of the Smallest Coding Unit (SCU) may be a predetermined maximum depth. Here, the LCU may be a CU having a maximum coding unit size as described above, and the SCU may be a CU having a minimum coding unit size.

The partitioning may be started from the LCU 310 and the depth of the CU may increase by one each time the horizontal and / or vertical size of the CU is reduced by partitioning.

For example, for each depth, the unpartitioned CU may have a size of 2Nx2N. Also, in the case of a CU to be divided, a CU having a size of 2Nx2N can be divided into four CUs having an NxN size. The size of N can be reduced by half each time the depth is increased by one.

Referring to FIG. 3, a LCU having a depth of 0 may be 64x64 pixels or 64x64 block. 0 may be the minimum depth. An SCU with a depth of 3 may be 8x8 pixels or 8x8 block. 3 may be the maximum depth. At this time, the CU of the 64x64 block, which is the LCU, can be represented by the depth 0. The CU of a 32x32 block can be represented by a depth of one. The CU of a 16x16 block can be represented by a depth of two. The CU of an 8x8 block that is an SCU can be represented by a depth of 3.

Information on whether or not the CU is divided can be expressed through the partition information of the CU. The division information may be 1-bit information. All CUs except SCU can contain partition information. For example, the value of the partition information of the unpartitioned CU may be 0, and the value of the partition information of the partitioned CU may be 1.

For example, when one CU is divided into four CUs, the horizontal size and the vertical size of each CU of the four CUs generated by the division are respectively half of the horizontal size and half of the vertical size of the CU before division . When a 32x32 CU is divided into 4 CUs, the sizes of the 4 divided CUs may be 16x16. When one CU is divided into four CUs, it can be said that the CU is divided into quad-tree form.

For example, when one CU is divided into two CUs, the horizontal size or the vertical size of each CU of the two CUs generated by the division is respectively one half of the horizontal size of the CU before the division, . When a 32x32 CU is vertically divided into two CUs, the sizes of the two divided CUs may be 16x32. When one CU is divided into two CUs, it can be said that the CU is divided into a binary-tree form.

In addition to the quad-tree type partitioning, the LCU 310 may also be partitioned in a binary-tree form.

Fig. 4 is a diagram showing a form of a prediction unit (PU) that a coding unit (CU) can include.

A CU that is not further divided among the CUs divided from the LCU may be divided into one or more Prediction Units (PUs).

The PU may be a base unit for prediction. The PU may be coded and decoded in either a skip mode, an inter mode, or an intra mode. The PU can be divided into various forms according to each mode. For example, the target block described above with reference to FIG. 1 and the target block described above with reference to FIG. 2 may be a PU.

In the skip mode, there may be no division in the CU. In the skip mode, the 2Nx2N mode 410 having the same sizes of PU and CU without division can be supported.

In inter mode, eight subdivided forms within the CU can be supported. For example, in the inter mode, 2Nx2N mode 410, 2NxN mode 415, Nx2N mode 420, NxN mode 425, 2NxnU mode 430, 2NxnD mode 435, nLx2N mode 440, Mode 445 may be supported.

In the intra mode, 2Nx2N mode 410 and NxN mode 425, 2NxN mode and Nx2N can be supported.

In the 2Nx2N mode 410, a PU of size 2Nx2N may be encoded. A PU of size 2Nx2N can mean a PU of the same size as a CU. For example, a PU of size 2Nx2N may have a size of 64x64, 32x32, 16x16, or 8x8.

In the NxN mode 425, the PU of the size NxN can be encoded.

For example, in intra prediction, when the size of the PU is 8x8, four divided PUs can be encoded. The size of the partitioned PU may be 4x4.

When the PU is encoded by the intra mode, the PU may be encoded using one of the plurality of intra prediction modes. For example, the High Efficiency Video Coding (HEVC) technique may provide 35 intra prediction modes, and the PU may be coded into one of the 35 intra prediction modes.

The mode in which the PU is encoded by the 2Nx2N mode 410 and the NxN mode 425 can be determined by the rate-distortion cost.

The encoding apparatus 100 can perform the encoding operation on the 2Nx2N size PU. Here, the encoding operation may be to encode the PU in each of a plurality of intra prediction modes that the encoding apparatus 100 can use. The optimal intra prediction mode for the 2Nx2N size PU can be derived through the encoding operation. The optimal intra prediction mode may be an intra prediction mode in which a minimum rate-distortion cost is incurred for encoding 2Nx2N sized PUs among a plurality of intra prediction modes available for use by the encoding apparatus 100. [

Also, the encoding apparatus 100 can sequentially perform encoding operations on each PU of PUs divided into NxN. Here, the encoding operation may be to encode the PU in each of a plurality of intra prediction modes that the encoding apparatus 100 can use. An optimal intra prediction mode for an NxN size PU can be derived through an encoding operation. The optimal intra prediction mode may be an intra prediction mode in which a minimum rate-distortion cost is incurred for encoding of NxN-sized PUs among a plurality of intra prediction modes available for use by the encoding apparatus 100. [

5 is a diagram showing a form of a conversion unit (TU) which can be included in a coding unit (CU).

A Transform Unit (TU) may be a base unit used for transform, quantization, inverse transform, inverse quantization, entropy coding, and entropy decoding processes within a CU. The TU may have a square shape or a rectangular shape.

Of the CUs segmented from the LCU, the CUs that are no longer divided into CUs may be divided into one or more TUs. At this time, the partition structure of the TU may be a quad-tree structure. For example, as shown in FIG. 5, one CU 510 may be divided one or more times according to the quad-tree structure. Through partitioning, one CU 510 can be composed of TUs of various sizes.

In the encoding apparatus 100, a 64.times.64 Coding Tree Unit (CTU) can be divided into a smaller number of CUs by a recursive quad-crree structure. One CU may be divided into four CUs having the same sizes. CUs can be recursively partitioned, and each CU can have a quad-tree structure.

The CU can have depth. If the CU is partitioned, the CUs generated by partitioning may have an increased depth by one in the depth of the partitioned CU.

For example, the depth of the CU may have a value from 0 to 3. The size of the CU may range from 64x64 to 8x8 depending on the depth of the CU.

Through recursive partitioning for CU, an optimal partitioning method that yields the lowest rate-distortion ratio can be selected.

6 is a diagram for explaining an embodiment of an intra prediction process.

The arrows from the center to the outline of the graph of FIG. 6 may indicate the prediction directions of the intra-prediction modes. In addition, the number indicated close to the arrow may represent an example of the mode value assigned to the prediction direction of the intra-prediction mode or the intra-prediction mode.

Intra coding and / or decoding may be performed using reference samples of the units around the target block. The surrounding block may be the reconstructed block around. For example, intra-coding and / or decoding may be performed using values or coding parameters of reference samples included in the reconstructed neighboring blocks.

The encoding apparatus 100 and / or the decoding apparatus 200 can generate a prediction block by performing intra prediction on a target block based on information of samples in the target image. When performing intra prediction, the encoding apparatus 100 and / or the decoding apparatus 200 may generate a prediction block for a target block by performing intra prediction based on information of samples in the target image. When performing intra prediction, the encoding apparatus 100 and / or the decoding apparatus 200 may perform directional prediction and / or non-directional prediction based on at least one reconstructed reference sample.

The prediction block may refer to a block generated as a result of performing intra prediction. The prediction block may correspond to at least one of CU, PU, and TU.

The unit of the prediction block may be at least one of CU, PU, and TU. The prediction block may have the form of a square having a size of 2Nx2N or a size of NxN. The size of NxN may include 4x4, 8x8, 16x16, 32x32 and 64x64.

Alternatively, the prediction block may be a rectangular block having MxN size such as 2x8, 4x8, 2x16, 4x16, and 8x16.

Intra prediction may be performed according to the intra prediction mode for the target block. The number of intra prediction modes that a target block may have may be a predetermined fixed value and may be a value determined differently depending on the property of the prediction block. For example, the attributes of the prediction block may include the size of the prediction block and the type of the prediction block.

For example, the number of intra prediction modes can be fixed to 35 irrespective of the size of the prediction block. Or, for example, the number of intra prediction modes may be 3, 5, 9, 17, 34, 35 or 36, and so on.

The intra prediction mode may be a non-directional mode or a directional mode. For example, the intra prediction mode may include two non-directional modes and 33 directional modes as shown in FIG.

The non-directional mode may include a DC mode and a planar mode. For example, the mode value of the DC mode may be one. The mode value of the planner mode may be zero.

The directional modes may be a prediction mode having a specific direction or a specific angle. Among the plurality of intra prediction modes, the remaining modes except for the DC mode and the planar mode may be the directional mode.

The intra prediction mode may be represented by at least one of a mode number, a mode value, a mode number, and a mode angle. The number of intra prediction modes may be M. M may be at least one. That is to say, the intra prediction mode may be M numbers including the number of non-directional modes and the number of directional modes.

The number of intra prediction modes can be fixed to M irrespective of the size of the block. Alternatively, the number of intra prediction modes may differ depending on the size of the block and / or the type of color component. For example, the number of prediction modes may be different depending on whether the color component is a luma signal or a chroma signal. For example, the larger the block size, the larger the number of intra prediction modes. Or the number of intra prediction modes of the luma component block may be greater than the number of intra prediction modes of the chrominance component block.

For example, in the case of a vertical mode with a mode value of 26, the prediction can be performed in the vertical direction based on the pixel value of the reference sample.

The encoding apparatus 100 and the decoding apparatus 200 can perform intra prediction on a target unit using a reference sample according to an angle corresponding to the directional mode even in the directional mode other than the above-described mode.

The intra prediction mode located on the right side of the vertical mode may be referred to as a vertical-right mode. The intra prediction mode located at the lower end of the horizontal mode may be named a horizontal-below mode. For example, in FIG. 6, the intra prediction modes in which the mode value is one of 27, 28, 29, 30, 31, 32, 33, and 34 may be vertical right modes 613. Intra prediction modes where the mode value is one of 2, 3, 4, 5, 6, 7, 8, and 9 may be horizontal lower modes 616.

The number of intra prediction modes described above and the mode value of each intra prediction mode may be exemplary only. The number of intra prediction modes described above and the mode value of each intra prediction mode may be differently defined according to the embodiment, implementation and / or necessity.

A step of checking whether samples included in the restored neighboring block can be used as a reference sample of the target block to perform intra prediction on the target block can be performed. If there is a sample which is not available as a reference sample of the current block among the samples of the neighboring block, a value generated by copying and / or interpolation using at least one sample value of samples included in the reconstructed neighboring block It can be replaced with the sample value of the sample which is not available as a reference sample. If the value generated by copying and / or interpolation is replaced with the sample value of the sample, the sample may be used as a reference sample of the target block.

In intra prediction, a filter may be applied to at least one of a reference sample or a prediction sample based on at least one of an intra prediction mode and a size of a target block.

When the intra prediction mode is the planar mode, in generating the prediction block of the target block, the upper reference sample of the target sample, the left reference sample of the target sample, the upper right reference sample of the target block And a weighted sum of the lower left reference samples of the target block may be used to generate a sample value of the prediction target sample.

When the intra prediction mode is the DC mode, in generating the prediction block of the target block, the average value of the upper reference samples and the left reference samples of the target block may be used.

When the intra prediction mode is the directional mode, a prediction block can be generated using the upper reference sample, the left reference sample, the upper right reference sample, and / or the lower left reference sample of the target block.

Real-unit interpolation may be performed to generate the prediction samples described above.

The intra prediction mode of the target block can be predicted from the intra prediction of the neighboring block of the target block, and the information used for prediction can be entropy encoded / decoded.

For example, if the intraprediction modes of the target block and the neighboring blocks are the same, it can be signaled that the intraprediction modes of the target block and the neighboring block are the same using the predetermined flag.

For example, an indicator indicating an intra prediction mode that is the same as the intra prediction mode of the target block among the intra prediction modes of a plurality of neighboring blocks may be signaled.

If the intra-prediction modes of the target block and the neighboring blocks are different from each other, information of the intra-prediction mode of the target block may be entropy-encoded / decoded based on the intra-prediction mode of the neighboring block.

7 is a view for explaining the positions of reference samples used in the intra prediction process.

7 shows the position of a reference sample used for intra prediction of a target block. 7, a reconstructed reference sample used for intra prediction of a target block includes lower-left reference samples 731, left reference samples 733, an upper- left corner reference samples 735, top reference samples 737 and top-right reference samples 739, and the like.

For example, the left reference samples 733 may refer to reconstructed reference pixels adjacent to the left side of the target block. Top reference samples 737 may refer to a reconstructed reference pixel adjacent the top of the target block. The upper left corner reference sample 735 may refer to a reconstructed reference pixel located at the upper left corner of the object block. In addition, the lower left reference samples 731 may refer to a reference sample located at the lower end of the left sample line among the samples located on the same line as the left sample line composed of the left reference samples 733. [ Upper right reference samples 739 may refer to reference samples located on the right side of the upper pixel line among the samples located on the same line as the upper sample line composed of upper reference samples 737. [

When the size of the target block is NxN, the lower left reference samples 731, the left reference samples 733, the upper reference samples 737, and the upper right reference samples 739 may be N, respectively.

A prediction block can be generated through intraprediction of a target block. The generation of the prediction block may include determining the value of the pixels of the prediction block. The size of the target block and the size of the prediction block may be the same.

The reference sample used for intra prediction of the target block may be changed depending on the intra prediction mode of the target block. The direction of the intra-prediction mode may indicate a dependency between the reference samples and the pixels of the prediction block. For example, the value of the specified reference sample may be used as the value of one or more specified pixels of the prediction block. In this case, the specified reference sample and the specified one or more pixels of the prediction block may be samples and pixels designated by a straight line in the direction of the intra prediction mode. That is to say, the value of the specified reference sample can be copied to the value of the pixel located in the reverse direction of the intra prediction mode. Alternatively, the value of the pixel of the prediction block may be the value of the reference sample located in the direction of the intra-prediction mode with respect to the position of the pixel.

For example, if the intra prediction mode of the target block is a vertical mode with a mode value of 26, upper reference samples 737 may be used for intra prediction. When the intra prediction mode is the vertical mode, the value of the pixel of the prediction block may be the value of the reference sample vertically positioned with respect to the position of the pixel. Thus, top reference samples 737 that are adjacent to the top of the target block may be used for intra prediction. In addition, the values of the pixels of a row of the prediction block may be the same as the values of the upper reference samples 737. [

For example, when the mode value of the intra prediction mode of the target block is 18, at least a part of the left reference samples 733, at least a part of the upper left corner reference sample 735 and the upper reference samples 737, Can be used. If the mode value of the intra prediction mode is 18, the value of the pixel of the prediction block may be a value of the reference sample located diagonally to the left of the upper side with respect to the pixel.

The reference sample used to determine the pixel value of one pixel of the prediction block may be one, or may be two or more.

The pixel value of the pixel of the prediction block as described above can be determined according to the position of the pixel and the position of the reference sample indicated by the direction of the intra prediction mode. If the position of the pixel and the position of the reference sample pointed by the direction of the intra prediction mode is an integer position, the value of one reference sample pointed to by the integer position can be used to determine the pixel value of the pixel of the prediction block.

If the position of the pixel and the position of the reference sample pointed by the direction of the intra prediction mode is not an integer position then an interpolated reference sample may be generated based on the two reference samples closest to the location of the reference sample have. The value of the interpolated reference sample may be used to determine the pixel value of the pixel of the prediction block. That is, when the position of the pixel of the prediction block and the position of the reference sample pointed by the direction of the intra prediction mode indicate between the two reference samples, an interpolated value is generated based on the values of the two samples .

The prediction block generated by the prediction may not be the same as the original target block. That is, there may be a prediction error which is a difference between the target block and the prediction block, and a prediction error may exist between the pixels of the target block and the pixels of the prediction block.

In the following, the terms "difference", "error" and "residual" may be used interchangeably and may be used interchangeably.

For example, in the case of directional intra prediction, the greater the distance between the pixel of the prediction block and the reference sample, the larger the prediction error may occur. Discontinuity may occur between the prediction block generated by the prediction error and the neighboring blocks.

Filtering for the prediction block may be used to reduce the prediction error. The filtering may be adaptively applying a filter to an area of the prediction block that is considered to have a large prediction error. For example, the region considered as having a large prediction error may be the boundary of the prediction block. In addition, depending on the intra-prediction mode, an area regarded as having a large prediction error among the prediction blocks may be different, and the characteristics of the filter may be different.

8 is a diagram for explaining an embodiment of the inter prediction process.

The rectangle shown in FIG. 8 may represent an image (or a picture). In Fig. 8, the arrow indicates the prediction direction. That is, the image can be encoded and / or decoded according to the prediction direction.

Each image can be classified into an I picture (Intra Picture), a P picture (Uni-prediction Picture), and a B picture (Bi-prediction Picture) according to the coding type. Each picture can be coded according to the coding type of each picture.

If the object image to be encoded is an I-picture, the object image can be encoded using data in the image itself without inter-prediction referring to other images. For example, an I-picture can be encoded only by intra prediction.

When the target image is a P picture, the target image can be encoded by inter prediction using only reference pictures existing in a unidirection. Here, the unidirectional may be forward or reverse.

When the target image is a B picture, the target image can be encoded by inter prediction using bi-directional reference pictures or inter prediction using reference pictures existing in one direction of forward and backward directions. Here, both directions may be forward and backward.

P-pictures and B-pictures that are encoded and / or decoded using reference pictures can be regarded as pictures in which inter-prediction is used.

In the following, inter prediction in the inter mode according to the embodiment will be described in detail.

Inter prediction can be performed using motion information.

In inter mode, the encoding apparatus 100 can perform inter prediction and / or motion compensation on a target block. The decoding apparatus 200 may perform inter-prediction and / or motion compensation corresponding to inter-prediction and / or motion compensation in the encoding apparatus 100 with respect to a target block.

The motion information for the target block can be derived during inter-prediction by the encoding apparatus 100 and the decoding apparatus 200, respectively. The motion information may be derived using motion information of a restored neighboring block, motion information of a collocated block (col block), and / or motion information of a block adjacent to a call block. The call block may be a block in a collocated picture (col picture). The position of the call block in the call picture may correspond to the position in the target image of the target block. The call picture may be one of at least one reference picture included in the reference picture list.

For example, the coding apparatus 100 or the decoding apparatus 200 may perform prediction and / or motion compensation by using motion information of a spatial candidate and / or a temporal candidate as motion information of a target block Can be performed. The target block may refer to a PU and / or PU partition.

The spatial candidate may be a reconstructed block spatially adjacent to the target block.

The temporal candidate may be a reconstructed block corresponding to a target block in a collocated picture (col picture) that has already been reconstructed.

In the inter prediction, the coding apparatus 100 and the decoding apparatus 200 can improve coding efficiency and decoding efficiency by using motion information of spatial candidates and / or temporal candidates. The motion information of the spatial candidate may be referred to as spatial motion information. The temporal candidate motion information may be referred to as temporal motion information.

Hereinafter, the motion information of the spatial candidate may be the motion information of the PU including the spatial candidate. The motion information of the temporal candidate may be the motion information of the PU including the temporal candidate. The motion information of the candidate block may be the motion information of the PU including the candidate block.

Inter prediction can be performed using a reference picture.

The reference picture may be at least one of a previous picture of a target picture or a subsequent picture of a target picture. The reference picture may refer to an image used for prediction of a target block.

In inter prediction, an area in a reference picture can be specified by using a reference picture index (or refIdx) indicating a reference picture and a motion vector or the like to be described later. Here, the specified area in the reference picture may indicate a reference block.

Inter prediction can select a reference picture and can select a reference block corresponding to a target block in a reference picture. In addition, the inter prediction can generate a prediction block for a target block using the selected reference block.

The motion information may be derived during inter-prediction by the encoding apparatus 100 and the decoding apparatus 200, respectively.

The spatial candidate may be 1) existing in the target picture, 2) already reconstructed through encoding and / or decoding, and 3) adjacent to the target block or a block located at the corner of the target block. Here, a block located at a corner of a target block may be a block vertically adjacent to a neighboring block that is laterally adjacent to the target block, or a block that is laterally adjacent to a neighboring block vertically adjacent to the target block. The "block located at the corner of the target block" may have the same meaning as "the block adjacent to the corner of the target block ". The "block located at the corner of the target block" may be included in the "block adjacent to the target block ".

For example, the spatial candidate may be a reconstructed block located on the left side of the target block, a reconstructed block located on the top of the target block, a reconstructed block located in the lower left corner of the target block, The reconstructed block or the reconstructed block located in the upper left corner of the target block.

Each of the encoding apparatus 100 and the decoding apparatus 200 can identify a block existing in a position spatially corresponding to a target block in a col picture. The position of the target block in the target picture and the position of the identified block in the call picture can correspond to each other.

Each of the encoding apparatus 100 and the decoding apparatus 200 can determine a col block existing at a predetermined relative position with respect to the identified block as a temporal candidate. The predetermined relative position may be a position inside the identified block and / or an outside position.

For example, the call block may include a first call block and a second call block. When the coordinates of the identified block are (xP, yP) and the size of the identified block is (nPSW, nPSH), the first call block may be a block located in the coordinates (xP + nPSW, yP + nPSH). The second call block may be a block located in the coordinates (xP + (nPSW >> 1), yP + (nPSH >> 1). The second call block may optionally be used when the first call block is unavailable.

The motion vector of the target block may be determined based on the motion vector of the call block. Each of the encoding apparatus 100 and the decoding apparatus 200 can scale a motion vector of a call block. A scaled motion vector of the call block can be used as a motion vector of the target block. In addition, the motion vector of the temporal candidate motion information stored in the list may be a scaled motion vector.

The ratio of the motion vector of the target block and the motion vector of the call block may be the same as the ratio of the first distance and the second distance. The first distance may be a distance between a reference picture and a target picture of a target block. The second distance may be the distance between the reference picture of the call block and the call picture.

The derivation method of the motion information can be changed according to the inter prediction mode of the target block. For example, there may be an inter-prediction mode applied for inter prediction, such as an Advanced Motion Vector Predictor (AMVP) mode, a merge mode and a skip mode, and a current picture reference mode have. The merge mode may also be referred to as a motion merge mode. Each of the modes will be described in detail below.

1) AMVP mode

When the AMVP mode is used, the encoding apparatus 100 can search for similar blocks in the vicinity of the target block. The encoding apparatus 100 can obtain a prediction block by performing prediction on a target block using motion information of a similar similar block. The encoding apparatus 100 can code residual blocks that are the difference between the target block and the prediction block.

1-1) Creation of Predicted Motion Vector Candidate List

When the AMVP mode is used as the prediction mode, each of the encoding apparatus 100 and the decoding apparatus 200 can generate a predicted motion vector candidate list using a spatial candidate motion vector, a temporal motion motion vector, and a zero vector have. The predicted motion vector candidate list may include one or more predicted motion vector candidates. At least one of a motion vector of a spatial candidate motion vector, a temporal candidate motion vector, and a zero vector may be determined and used as a predicted motion vector candidate.

Hereinafter, the terms "predicted motion vector (candidate)" and "motion vector (candidate)" may be used interchangeably and may be used interchangeably.

The spatial motion candidate may include reconstructed spatial neighboring blocks. In other words, the motion vector of the reconstructed neighboring block may be referred to as a spatial prediction motion vector candidate.

The temporal motion candidate may include a call block and a block adjacent to the call block. In other words, a motion vector of a call block or a block adjacent to a call block may be referred to as a temporal prediction motion vector candidate.

The zero vector may be a (0, 0) motion vector.

The predicted motion vector candidate may be a motion vector predictor for predicting the motion vector. Also, in the encoding apparatus 100, the predicted motion vector candidate may be a motion vector initial search position.

1-2) Retrieving a motion vector using a predicted motion vector candidate list

The encoding apparatus 100 may use the predicted motion vector candidate list to determine a motion vector to be used for encoding the target block within the search range. Also, the encoding apparatus 100 can determine a predicted motion vector candidate to be used as a predicted motion vector of a target block among predicted motion vector candidates of the predicted motion vector candidate list.

A motion vector to be used for coding a target block may be a motion vector that can be encoded at a minimum cost.

Also, the encoding apparatus 100 can determine whether to use the AMVP mode in encoding the target block.

1-3) Transmission of inter prediction information

The encoding apparatus 100 can generate a bitstream including inter prediction information required for inter prediction. The decoding apparatus 200 may perform inter prediction on a target block using inter prediction information of a bit stream.

The inter prediction information includes 1) mode information indicating whether the AMVP mode is used, 2) a predicted motion vector index, 3) a motion vector difference (MVD), 4) a reference direction, and 5) can do.

Further, the inter prediction information may include a residual signal.

When the mode information indicates that the AMVP mode is used, the decoding apparatus 200 can obtain the predicted motion vector index, the motion vector difference, the reference direction, and the reference picture index from the bitstream through entropy decoding.

The predicted motion vector index may indicate a predicted motion vector candidate used for predicting a target block among the predicted motion vector candidates included in the predicted motion vector candidate list.

1-4) Inter prediction of AMVP mode using inter prediction information

The decoding apparatus 200 can derive a predicted motion vector candidate using the predicted motion vector candidate list and determine the motion information of the target block based on the derived predicted motion vector candidate.

The decoding apparatus 200 can determine a motion vector candidate for a target block from among the predicted motion vector candidates included in the predicted motion vector candidate list using the predicted motion vector index. The decoding apparatus 200 can select a predicted motion vector candidate pointed to by the predicted motion vector index among the predicted motion vector candidates included in the predicted motion vector candidate list as a predicted motion vector of the target block.

The motion vector to be actually used for inter prediction of the target block may not coincide with the predicted motion vector. The MVD may be used to represent the difference between the motion vector to be actually used for inter prediction of the target block and the predicted motion vector. The encoding apparatus 100 can derive a predictive motion vector similar to a motion vector to be actually used for inter prediction of a target block in order to use an MVD as small as possible.

The MVD may be a difference between a motion vector of a target block and a predicted motion vector. The encoding apparatus 100 can calculate the MVD and entropy-encode the MVD.

The MVD may be transmitted from the encoding apparatus 100 to the decoding apparatus 200 through a bitstream. The decoding apparatus 200 can decode the received MVD. The decoding apparatus 200 can derive a motion vector of a target block by adding the decoded MVD and the predicted motion vector. In other words, the motion vector of the target block derived from the decoding apparatus 200 may be the sum of the entropy-decoded MVD and the motion vector candidate.

The reference direction may indicate a reference picture list used for predicting a target block. For example, the reference direction may indicate one of the reference picture list L0 and the reference picture list L1.

The reference direction may refer to a reference picture list used for prediction of a target block, but may not indicate that the directions of the reference pictures are limited in a forward direction or a backward direction. That is to say, each of the reference picture list L0 and the reference picture list L1 may include forward and / or backward pictures.

The reference direction being uni-directional may mean that one reference picture list is used. The bi-directional reference direction may mean that two reference picture lists are used. That is to say, the reference direction may indicate that only the reference picture list L0 is used, only the reference picture list L1 is used, and one of the two reference picture lists.

The reference picture index may indicate a reference picture used for prediction of a target block among reference pictures of the reference picture list. The reference picture index can be entropy-encoded by the encoding apparatus 100. [ The entropy encoded reference picture index may be signaled from the encoding apparatus 100 to the decoding apparatus 200 through the bit stream.

When two reference picture lists are used for prediction of a target block. One reference picture index and one motion vector may be used for each reference picture list. In addition, when two reference picture lists are used for predicting a target block, two prediction blocks can be specified for a target block. For example, a (final) prediction block of a target block may be generated through an average or a weighted sum of two prediction blocks for a target block.

The motion vector of the target block can be derived by the predicted motion vector index, the MVD, the reference direction, and the reference picture index.

The decoding apparatus 200 may generate a prediction block for a target block based on the derived motion vector and the reference picture index. For example, the prediction block may be a reference block pointed to by the derived motion vector in the reference picture pointed to by the reference picture index.

The amount of bits to be transmitted from the encoding apparatus 100 to the decoding apparatus 200 can be reduced by encoding the predicted motion vector index and the MVD without encoding the motion vector of the target block and the encoding efficiency can be improved.

Motion information of the reconstructed neighboring blocks may be used for the target block. In the specific inter prediction mode, the encoding apparatus 100 may not separately encode the motion information on the target block. The motion information of the target block is not coded and other information capable of deriving the motion information of the target block through motion information of the reconstructed neighboring block can be encoded instead. As other information is encoded in place, the amount of bits to be transmitted to the decoding apparatus 200 can be reduced, and the coding efficiency can be improved.

For example, a skip mode and / or a merge mode may be an inter prediction mode in which motion information of the target block is not directly encoded. At this time, the encoding apparatus 100 and the decoding apparatus 200 may use an identifier and / or index indicating which one of the reconstructed neighboring units is used as motion information of the target unit.

2) Mersey mode

As a method for deriving motion information of a target block, there is a merge. A merge may mean a merging of movements for a plurality of blocks. Merging may mean applying motion information of one block to another block as well. In other words, the merge mode may mean a mode in which motion information of a target block is derived from motion information of a neighboring block.

When the merge mode is used, the encoding apparatus 100 can predict motion information of a target block using motion information of a spatial candidate and / or motion information of a temporal candidate. The spatial candidate may include reconstructed spatial neighboring blocks spatially adjacent to the object block. Spatially adjacent blocks may include a left adjacent block and an upper adjacent block. The temporal candidate may include a call block. The terms "spatial candidate" and "spatial merge candidate" can be used interchangeably and can be used interchangeably. The terms "temporal candidate" and "temporal merge candidate" can be used interchangeably and can be used interchangeably.

The encoding apparatus 100 can obtain a prediction block through prediction. The encoding apparatus 100 can code residual blocks that are the difference between the target block and the prediction block.

2-1) Creating a merge candidate list

When the merge mode is used, each of the encoding apparatus 100 and the decoding apparatus 200 can generate a merge candidate list using motion information of a spatial candidate and / or motion information of a temporal candidate. The motion information may include 1) a motion vector, 2) a reference picture index, and 3) a reference direction. The reference direction may be unidirectional or bidirectional.

The merge candidate list may include merge candidates. The merge candidate may be motion information. That is to say, the merge candidate list may be a list in which motion information is stored.

The merge candidates may be motion information such as temporal candidates and / or spatial candidates. In addition, the merge candidate list may include a new merge candidate generated by a combination of merge candidates already present in the merge candidate list. That is, the merge candidate list may include new motion information generated by a combination of motion information already present in the merge candidate list.

Also, the merge candidate list may include motion information of a zero vector. Zero vectors may also be called zero-merge candidates.

In other words, the motion information in the merge candidate list includes: 1) motion information of a spatial candidate, 2) motion information of a temporal candidate, 3) motion information generated by a combination of motion information existing in an already existing candidate list, 4) Lt; / RTI >

The motion information may include 1) a motion vector, 2) a reference picture index, and 3) a reference direction. The reference direction may be referred to as an inter prediction indicator. The reference direction may be unidirectional or bidirectional. The unidirectional reference direction may represent L0 prediction or L1 prediction.

The merge candidate list can be generated before the prediction by merge mode is performed.

The number of merge candidates in the merge candidate list can be predetermined. The encoding apparatus 100 and the decrypting apparatus 200 may add a merge candidate to the merge candidate list according to the predefined manner and the predefined rank so that the merge candidate list has a predetermined number of merge candidates. The merge candidate list of the encoding apparatus 100 and the merge candidate list of the decryption apparatus 200 may be the same through the predetermined scheme and the default rank.

The merge can be applied in CU units or PU units. When the merging is performed in units of CU or PU, the encoding apparatus 100 may transmit the bitstream including the predetermined information to the decoding apparatus 200. [ For example, the predefined information may include: 1) information indicating whether to perform a merge by block partitions, 2) a block to be merged with any block among the blocks that are spatial candidates and / or temporal candidates for the target block And information about whether or not it is possible.

2-2) Search of motion vectors using merge candidate list

The encoding apparatus 100 can determine a merge candidate to be used for encoding the target block. For example, the encoding apparatus 100 may use the merge candidates of the merge candidate list to perform predictions on the target block, and generate residual blocks for the merge candidates. The encoding apparatus 100 can use the merge candidate requiring minimum cost in prediction and encoding of the residual block for encoding the target block.

Further, the encoding apparatus 100 can determine whether to use the merge mode in encoding the target block.

2-3) Transmission of inter prediction information

The encoding apparatus 100 can generate a bitstream including inter prediction information required for inter prediction. The encoding apparatus 100 may generate entropy-encoded inter prediction information by performing entropy encoding on the inter prediction information, and may transmit the bit stream including the entropy-encoded inter prediction information to the decoding apparatus 200. Through the bitstream, entropy-encoded inter prediction information can be signaled from the encoding apparatus 100 to the decoding apparatus 200. [

The decoding apparatus 200 may perform inter prediction on a target block using inter prediction information of a bit stream.

The inter prediction information may include 1) mode information indicating whether the merge mode is used, and 2) a merge index.

Further, the inter prediction information may include a residual signal.

The decoding apparatus 200 can obtain a merge index from the bit stream only when the mode information indicates that the merge mode is used.

The mode information may be a merge flag. The unit of mode information may be a block. The information about the block may include mode information, and the mode information may indicate whether the merge mode is applied to the block.

The merge index may indicate a merge candidate used for predicting a target block among merge candidates included in the merge candidate list. Alternatively, the merge index may indicate which of the neighboring blocks spatially or temporally adjacent to the target block is merged with.

2-4) Inter prediction in merge mode using inter prediction information

The decoding apparatus 200 can perform the prediction on the target block using merge candidates indicated by the merge index among merge candidates included in the merge candidate list.

The motion vector of the target block may be specified by the motion vector of the merge candidate pointed to by the merge index, the reference picture index, and the reference direction.

3) Skip Mode

The skip mode may be a mode in which motion information of a spatial candidate or motion information of a temporal candidate is directly applied to a target block. The skip mode may be a mode in which the residual signal is not used. That is to say, when the skip mode is used, the reconstructed block may be a prediction block.

The difference between the merge mode and the skip mode may be the transmission or use of the residual signal. That is to say, the skip mode may be similar to the merge mode, except that the residual signal is not transmitted or used.

When the skip mode is used, the encoding apparatus 100 transmits information indicating which of the blocks, which are spatial candidates or temporal candidates, is to be used as motion information of the target block, to the decoding apparatus 200 through the bit stream Lt; / RTI > The encoding apparatus 100 may generate entropy-encoded information by performing entropy encoding on the information, and may signal entropy-encoded information to the decoding apparatus 200 through the bitstream.

In addition, when the skip mode is used, the encoding apparatus 100 may not transmit other syntax element information such as MVD to the decryption apparatus 200. [ For example, when used in the skip mode, the encoding apparatus 100 may not signal a syntax element related to at least one of the MVC, the coded block flag, and the transform coefficient level to the decoding apparatus 200. [

3-1) Preparation of merge candidate list

Skipped mode You can also use the merge candidate list. That is to say, the merge candidate list can be used in both merge mode and skip mode. In this regard, the merge candidate list may be named a "skip candidate list" or a "merge / skip candidate list ".

Alternatively, the skip mode may use a separate candidate list different from the merge mode. In this case, the merge candidate list and merge candidate in the following description can be replaced with a skip candidate list and a skip candidate, respectively.

The merge candidate list can be generated before the prediction by the skip mode is performed.

3-2) Search of motion vectors using merge candidate list

The encoding apparatus 100 can determine a merge candidate to be used for encoding the target block. For example, the encoding apparatus 100 may perform predictions on a target block using merge candidates of a merge candidate list. The encoding apparatus 100 can use the merge candidate requiring minimum cost in prediction for encoding the target block.

Further, the encoding apparatus 100 can determine whether to use the skip mode in encoding the target block.

3-3) Transmission of inter prediction information

The encoding apparatus 100 can generate a bitstream including inter prediction information required for inter prediction. The decoding apparatus 200 may perform inter prediction on a target block using inter prediction information of a bit stream.

The inter prediction information may include 1) mode information indicating whether a skip mode is used, and 2) a skip index.

The skip index may be the same as the merge index described above.

When skip mode is used, the target block can be encoded without a residual signal. The inter prediction information may not include the residual signal. Alternatively, the bitstream may not include the residual signal.

The decoding apparatus 200 can acquire the skip index from the bit stream only when the mode information indicates that the skip mode is used. As described above, the merge index and the skip index may be the same. The decoding apparatus 200 can acquire the skip index from the bit stream only when the mode information indicates that the merge mode or the skip mode is used.

The skip index may indicate a merge candidate used for predicting a target block among merge candidates included in the merge candidate list.

3-4) Inter prediction of skip mode using inter prediction information

The decoding apparatus 200 can perform prediction on the target block using merge candidates indicated by the skip index among merge candidates included in the merge candidate list.

The motion vector of the target block may be specified by the motion vector of the merge candidate pointed to by the skip index, the reference picture index, and the reference direction.

4) Current picture reference mode

The current picture reference mode may refer to a prediction mode using the preexisting reconstructed region in the current picture to which the target block belongs.

A vector may be defined to identify the pre-reconstructed region. Whether or not the target block is coded in the current picture reference mode can be determined using the reference picture index of the target block.

A flag or an index indicating whether the target block is a block coded in the current picture reference mode may be signaled from the coding apparatus 100 to the decoding apparatus 200. [ Alternatively, whether the target block is a block coded in the current picture reference mode may be inferred through the reference picture index of the target block.

When the target block is coded in the current picture reference mode, the current picture can be added to a fixed position or an arbitrary position in the reference picture list for the target block.

For example, the fixed position may be the position where the reference picture index is 0 or the last position.

When the current picture is added to any position in the reference picture list, a separate reference picture index indicating this arbitrary position may be signaled from the coding apparatus 100 to the decoding apparatus 200. [

In the above-described AMVP mode, merge mode, and skip mode, motion information to be used for prediction of a target block among the motion information in the list can be specified through the index for the list.

In order to improve the coding efficiency, the coding apparatus 100 can signal only the index of the element causing the minimum cost in the inter prediction of the target block among the elements of the list. The encoding apparatus 100 can encode an index and signal the encoded index.

Accordingly, the above-described lists (i.e., the predicted motion vector candidate list and the merge candidate list) may have to be derived in the same manner based on the same data in the encoding apparatus 100 and the decrypting apparatus 200. [ Here, the same data may include reconstructed pictures and reconstructed blocks. Also, in order to specify an element by index, the order of the elements in the list may have to be constant.

Figure 9 shows spatial candidates according to an example.

In Figure 9, the location of spatial candidates is shown.

A large block in the middle can represent a target block. The five small blocks may represent spatial candidates.

The coordinates of the target block may be (xP, yP), and the size of the target block may be (nPSW, nPSH).

The spatial candidate A ₀ may be a block adjacent to the lower left corner of the target block. A ₀ may be a block occupying a pixel of coordinates (xP - 1, yP + nPSH + 1).

The spatial candidate A ₁ may be a block adjacent to the left of the target block. A ₁ may be the lowermost block among the blocks adjacent to the left of the target block. Alternatively, A ₁ may be a block adjacent to the top of A ₀ . A ₁ may be a block occupying a pixel of coordinates (xP - 1, yP + nPSH).

The spatial candidate B ₀ may be a block adjacent to the upper right corner of the target block. B ₀ may be a block occupying a pixel of coordinates (xP + nPSW + 1, yP-1).

The spatial candidate B ₁ may be a block adjacent to the top of the target block. B ₁ may be the rightmost block among the blocks adjacent to the top of the target block. Alternatively, B ₁ may be a block adjacent to the left of B ₀ . B ₁ may be a block occupying the pixels of the coordinates (xP + nPSW, yP-1).

The spatial candidate B ₂ may be a block adjacent to the upper left corner of the target block. B ₂ may be a block occupying pixels of coordinates (xP-1, yP-1).

Determining Availability of Spatial and Temporal Candidates

In order to include motion information of a spatial candidate or motion information of a temporal candidate, it is necessary to determine whether motion information of a spatial candidate or motion information of a temporal candidate is available.

Hereinafter, the candidate block may include spatial candidates and temporal candidates.

For example, the above determination can be made by sequentially applying the following steps 1) to 4).

Step 1) If the PU including the candidate block is outside the boundary of the picture, the availability of the candidate block may be set to false. "Availability is set to false" may be synonymous with "set to unavailable ".

Step 2) If the PU including the candidate block is outside the boundary of the slice, the availability of the candidate block may be set to false. If the target block and the candidate block are located in different slices, the availability of the candidate block may be set to false.

Step 3) If the PU including the candidate block is outside the boundary of the tile, the availability of the candidate block may be set to false. If the target block and the candidate block are located in different tiles, the availability of the candidate block may be set to false.

Step 4) If the prediction mode of the PU including the candidate block is the intra prediction mode, the availability of the candidate block may be set to false. If the PU including the candidate block does not use inter prediction, the availability of the candidate block may be set to false.

FIG. 10 shows an addition sequence of motion information of spatial candidates to a merge list according to an example.

As shown in FIG. 10, in order to add motion information of spatial candidates to the merge list, a sequence of A ₁ , B ₁ , B ₀ , A _0, and B ₂ may be used. That is, the motion information of available spatial candidates can be added to the merged list in the order of A ₁ , B ₁ , B ₀ , A _0, and B ₂ .

How to derive a merge list in merge mode and skip mode

As described above, the maximum number of merge candidates in the merge list can be set. The set maximum number is denoted by N. The set number can be transferred from the encoding apparatus 100 to the decoding apparatus 200. [ The slice header of the slice may contain N. [ That is, the maximum number of merge candidates of the merge list for the target block of the slice can be set by the slice header. For example, basically the value of N may be 5.

The motion information (i.e., merge candidate) may be added to the merge list in the following order of steps 1) to 4) below.

Step 1) Available spatial candidates among the spatial candidates can be added to the merged list. The motion information of the available spatial candidates may be added to the merge list in the order shown in FIG. At this time, if the motion information of the available spatial candidate overlaps with other motion information already existing in the merge list, the motion information may not be added to the merge list. Checking whether or not to overlap with other motion information present in the list can be outlined as "redundancy check ".

The motion information to be added may be a maximum of N pieces.

Step 2) If the number of motion information in the merge list is smaller than N and temporal candidates are available, motion information of temporal candidates may be added to the merge list. At this time, if the available temporal candidate motion information overlaps with other motion information already existing in the merge list, the motion information may not be added to the merge list.

Step 3) If the number of pieces of motion information in the merge list is smaller than N and the type of the target slice is "B ", the combined motion information generated by the combined bi-prediction is added to the merge list .

The target slice may be a slice containing the target block.

The combined motion information may be a combination of L0 motion information and L1 motion information. The L0 motion information may be motion information that refers to only the reference picture list L0. The L1 motion information may be motion information referring to only the reference picture list L1.

Within the merge list, the L0 motion information may be one or more. Also, within the merge list, the L1 motion information may be one or more.

The combined motion information may be one or more. In generating the combined motion information, it is possible to determine which L0 motion information and which L1 motion information to use among one or more L0 motion information and one or more L1 motion information. The one or more combined motion information may be generated in a predetermined order by combined bidirectional prediction using a pair of different motion information in the merge list. One of the pairs of different motion information may be the L0 motion information and the other may be the L1 motion information.

For example, the highest combined motion information may be a combination of L0 motion information having a merge index of 0 and L1 motion information having a merge index of 1. If the motion information whose merge index is 0 is not L0 motion information, or the motion information whose merge index is 1 is not L1 motion information, the combined motion information may not be generated and added. The next motion information may be a combination of L0 motion information having a merge index of 1 and L1 motion information having a merge index of 0. [ The following specific combinations may follow different combinations of the encoding / decoding fields of moving pictures.

At this time, if the combined motion information overlaps with other motion information already existing in the merge list, the combined motion information may not be added to the merge list.

Step 4) If the number of motion information in the merge list is less than N, zero vector motion information may be added to the merge list.

The zero vector motion information may be motion information whose motion vector is a zero vector.

The zero vector motion information may be one or more. The reference picture indexes of one or more zero vector motion information may be different from each other. For example, the value of the reference picture index of the first zero vector motion information may be zero. The value of the reference picture index of the second zero vector motion information may be one.

The number of zero vector motion information may be equal to the number of reference pictures in the reference picture list.

The reference direction of the zero vector motion information may be bi-directional. The two motion vectors may all be zero vectors. The number of zero vector motion information may be the smaller of the number of reference pictures in the reference picture list L0 and the number of reference pictures in the reference picture list L1. Alternatively, when the number of reference pictures in the reference picture list L0 is different from the number of reference pictures in the reference picture list L1, a unidirectional reference direction can be used for a reference picture index that can be applied to only one reference picture list.

The coding apparatus 100 and / or the decoding apparatus 200 can sequentially add the zero vector motion information to the merged list while changing the reference picture index.

If the zero vector motion information overlaps with other motion information already present in the merge list, the zero vector motion information may not be added to the merge list.

The order of the above-described steps 1) to 4) is merely exemplary, and the order between the steps may be mutually exclusive. In addition, some of the steps may be omitted depending on the predefined conditions.

A method of deriving a predicted motion vector candidate list in AMVP mode

The maximum number of predicted motion vector candidates in the predicted motion vector candidate list can be predetermined. The default maximum number is denoted by N. For example, the default maximum number may be two.

The motion information (i.e., the predicted motion vector candidate) may be added to the predicted motion vector candidate list in the order of the following steps 1) to 3).

Step 1) Available spatial candidates among the spatial candidates can be added to the predicted motion vector candidate list. The spatial candidates may include a first spatial candidate and a second spatial candidate.

The first spatial candidate may be one of A ₀ , A ₁ , scaled A _0, and scaled A ₁ . The second spatial candidate may be one of B ₀ , B ₁ , B ₂ , Scaled B ₀ , Scaled B _1, and Scaled B ₂ .

The motion information of the available spatial candidates may be added to the predicted motion vector candidate list in the order of the first spatial candidate and the second spatial candidate. In this case, if the motion information of the available spatial candidate is already overlapped with other motion information existing in the predicted motion vector candidate list, the motion information may not be added to the predicted motion vector candidate list. That is, if the value of N is 2 and the motion information of the second spatial candidate is the same as the motion information of the first spatial candidate, the motion information of the second spatial candidate may not be added to the predicted motion vector candidate list.

The motion information to be added may be a maximum of N pieces.

Step 2) If the number of pieces of motion information in the predicted motion vector candidate list is smaller than N and temporal candidates are available, temporal motion information may be added to the predicted motion vector candidate list. In this case, if the motion information of the available temporal candidate overlaps with other motion information already present in the predicted motion vector candidate list, the motion information may not be added to the predicted motion vector candidate list.

Step 3) If the number of motion information in the predicted motion vector candidate list is smaller than N, zero vector motion information may be added to the predicted motion vector candidate list.

The zero vector motion information may be one or more. The reference picture indexes of one or more zero vector motion information may be different from each other.

The encoding apparatus 100 and / or the decoding apparatus 200 may sequentially add the zero vector motion information to the predicted motion vector candidate list while changing the reference picture index.

The zero vector motion information may not be added to the predicted motion vector candidate list if the zero vector motion information overlaps with other motion information already present in the predicted motion vector candidate list.

The description of the zero vector motion information described above for the merge list can also be applied to zero vector motion information. Duplicate descriptions are omitted.

The order of the steps 1) to 3) described above is merely exemplary, and the order between the steps may be mutually exclusive. In addition, some of the steps may be omitted depending on the predefined conditions.

Figure 11 illustrates the process of transform and quantization according to an example.

The quantized level may be generated by performing a conversion and / or quantization process on the residual signal as shown in FIG.

The residual signal can be generated as a difference between the original block and the prediction block. Here, the prediction block may be a block generated by intra prediction or inter prediction.

The transform may include at least one of a primary transform and a secondary transform. A transform coefficient may be generated by performing a first transform on the residual signal, and a second transform coefficient may be generated by performing a second transform on the transform coefficient.

The primary transform may be performed using at least one of a plurality of pre-defined transformation methods. For example, a plurality of pre-defined conversion methods may be based on Discrete Cosine Transform (DCT), Discrete Sine Transform (DST), and Karhunen-Loeb Transform (KLT) Conversion, and the like.

A secondary transform may be performed on the transform coefficients generated by performing the primary transform.

The transform method (s) applied to the primary transform and / or the quadratic transform may be determined according to at least one of the coding parameters for the object block and / or the surrounding block. Or conversion information indicating the conversion method may be signaled from the encoding device 100 to the decryption device 200. [

The quantized level can be generated by performing quantization on the result or residual signal generated by performing the primary conversion and / or the secondary conversion.

The quantized level may be scanned according to at least one of an upper right diagonal scan, a vertical scan, and a horizontal scan according to at least one of an intra prediction mode, a block size, and a block type.

For example, the coefficients may be changed to a one-dimensional vector form by scanning the coefficients of the block using up-right diagonal scanning. Alternatively, depending on the size of the transform block and / or the intra prediction mode, a vertical scan in which two-dimensional block form coefficients are scanned in the column direction instead of the upper-right diagonal scan, or a horizontal scan in which two- have.

The scanned quantization level may be entropy encoded and the bitstream may comprise an entropy encoded quantization level.

The decoding apparatus 200 can generate a quantized level through entropy decoding on the bitstream. The quantized levels can be arranged in a two-dimensional block form through inverse scanning. At this time, as a method of inverse scanning, at least one of top-right diagonal scanning, vertical scanning, and horizontal scanning may be performed.

Inverse quantization can be performed on the quantized levels. For the result generated by performing the inverse quantization, a second-order inverse transform can be performed depending on whether or not the second-order inverse transform is performed. In addition, for the result generated by performing the second-order inverse transform, the first-order inverse transform can be performed depending on whether or not the first-order inverse transform is performed. The restored residual signal can be generated by performing the first-order inverse transform on the result generated by performing the second-order inverse transform.

12 is a structural diagram of an encoding apparatus according to an embodiment.

The encoding apparatus 1200 may correspond to the encoding apparatus 100 described above.

The encoding device 1200 includes a processing unit 1210, a memory 1230, a user interface (UI) input device 1250, a UI output device 1260, and a storage 1260 that communicate with each other via a bus 1290. [ 1240 < / RTI > Also, the encoding apparatus 1200 may further include a communication unit 1220 connected to the network 1299.

The processing unit 1210 may be a semiconductor device that executes processing instructions stored in a central processing unit (CPU), memory 1230, or storage 1240. The processing unit 1210 may be at least one hardware processor.

The processing unit 1210 can generate and process signals, data, or information that are input to the encoding apparatus 1200, output from the encoding apparatus 1200, or used in the encoding apparatus 1200, Compare, and judge related to data or information. In other words, in the embodiment, the generation and processing of data or information and the inspection, comparison and judgment relating to data or information can be performed by the processing unit 1210.

The processing unit 1210 includes an inter prediction unit 110, an intra prediction unit 120, a switch 115, a subtractor 125, a transform unit 130, a quantization unit 140, an entropy coding unit 150, An inverse transform unit 170, an adder 175, a filter unit 180, and a reference picture buffer 190, as shown in FIG.

The inter prediction unit 110, the intra prediction unit 120, the switch 115, the subtractor 125, the transform unit 130, the quantization unit 140, the entropy coding unit 150, the inverse quantization unit 160, At least some of the inverse transform unit 170, the adder 175, the filter unit 180, and the reference picture buffer 190 may be program modules and may communicate with an external device or system. The program modules may be included in the encoding apparatus 1200 in the form of an operating system, an application program module, and other program modules.

The program modules may be physically stored on various known storage devices. At least some of these program modules may also be stored in a remote storage device capable of communicating with the encoding device 1200. [

Program modules may be implemented as a set of routines, subroutines, programs, objects, components, and data that perform functions or operations in accordance with one embodiment, implement an abstract data type according to one embodiment, Data structures, and the like, but are not limited thereto.

Program modules may be comprised of instructions or code that are executed by at least one processor of the encoding apparatus 1200. [

The processing unit 1210 includes an inter prediction unit 110, an intra prediction unit 120, a switch 115, a subtractor 125, a transform unit 130, a quantization unit 140, an entropy coding unit 150, The adder 175, the filter unit 180, and the reference picture buffer 190, as shown in FIG.

The storage may represent memory 1230 and / or storage 1240. Memory 1230 and storage 1240 may be various types of volatile or non-volatile storage media. For example, the memory 1230 may include at least one of a ROM (R) 1231 and a RAM (RAM)

The storage unit may store data or information used for the operation of the encoding apparatus 1200. In the embodiment, data or information possessed by the encoding apparatus 1200 may be stored in the storage unit.

For example, the storage unit may store pictures, blocks, lists, motion information, inter prediction information, bit streams, and the like.

The encoding apparatus 1200 may be embodied in a computer system including a recording medium that can be read by a computer.

The recording medium may store at least one module required for the encoding apparatus 1200 to operate. The memory 1230 may store at least one module, and at least one module may be configured to be executed by the processing unit 1210.

The function related to the communication of data or information of the encoding apparatus 1200 may be performed through the communication unit 1220. [

For example, the communication unit 1220 can transmit the bit stream to the decoding apparatus 1300 to be described later.

13 is a structural diagram of a decoding apparatus according to an embodiment.

The decoding apparatus 1300 may correspond to the decoding apparatus 200 described above.

The decryption device 1300 includes a memory 1330, a user interface (UI) input device 1350, a UI output device 1360 and a storage (not shown) that communicate with each other 1310 via a bus 1390 1340). In addition, the decryption apparatus 1300 may further include a communication unit 1320 connected to the network 1399.

The processing unit 1310 may be a semiconductor device that executes processing instructions stored in a central processing unit (CPU), memory 1330, or storage 1340. The processing unit 1310 may be at least one hardware processor.

The processing unit 1310 can generate and process signals, data, or information to be input to the decoding apparatus 1300, output from the decoding apparatus 1300 or used in the decoding apparatus 1300, Compare, and judge related to data or information. In other words, in the embodiment, the generation and processing of data or information and the checking, comparison and judgment relating to data or information can be performed by the processing unit 1310. [

The processing unit 1310 includes an entropy decoding unit 210, an inverse quantization unit 220, an inverse transform unit 230, an intra prediction unit 240, an inter prediction unit 250, an adder 255, a filter unit 260, And a reference picture buffer 270.

An entropy decoding unit 210, an inverse quantization unit 220, an inverse transform unit 230, an intra prediction unit 240, an inter prediction unit 250, an adder 255, a filter unit 260 and a reference picture buffer 270 ) May be program modules and may communicate with an external device or system. The program modules may be included in the decryption apparatus 1300 in the form of an operating system, an application program module, and other program modules.

The program modules may be physically stored on various known storage devices. Also, at least some of these program modules may be stored in a remote storage device capable of communicating with the decryption device 1300. [

Program modules may be implemented as a set of routines, subroutines, programs, objects, components, and data that perform functions or operations in accordance with one embodiment, implement an abstract data type according to one embodiment, Data structures, and the like, but are not limited thereto.

Program modules may be comprised of instructions or code that are executed by at least one processor of the decoding apparatus 1300. [

The processing unit 1310 includes an entropy decoding unit 210, an inverse quantization unit 220, an inverse transform unit 230, an intra prediction unit 240, an inter prediction unit 250, an adder 255, a filter unit 260, It is possible to execute an instruction or code of the reference picture buffer 270. [

The storage may represent memory 1330 and / or storage 1340. Memory 1330 and storage 1340 may be various types of volatile or non-volatile storage media. For example, the memory 1330 may include at least one of a ROM (ROM) 1331 and a RAM (RAM) 1332.

The storage unit may store data or information used for the operation of the decoding apparatus 1300. In the embodiment, the data or information possessed by the decryption apparatus 1300 can be stored in the storage unit.

For example, the storage unit may store pictures, blocks, lists, motion information, inter prediction information, bit streams, and the like.

The decryption apparatus 1300 may be implemented in a computer system including a recording medium that can be read by a computer.

The recording medium may store at least one module required for the decryption apparatus 1300 to operate. The memory 1330 may store at least one module, and at least one module may be configured to be executed by the processing unit 1310.

The function related to the communication of data or information of the decryption apparatus 1300 may be performed through the communication unit 1320. [

For example, the communication unit 1320 can receive the bit stream from the encoding device 1200. [

14 is a flowchart of a prediction method according to an embodiment.

The prediction method can be performed by the encoding apparatus 1200 and / or the decoding apparatus 1300. [

For example, the encoding apparatus 1200 can perform the prediction method of the embodiment to compare efficiencies of a plurality of prediction methods for a target block and / or a plurality of divided blocks, The prediction method of the embodiment can be performed to generate the block.

In one embodiment, the target block may be at least one of CTU, CU, PU, TU, a block with a specified size, and a block within the size of the predefined range.

For example, the decoding apparatus 1300 may perform the prediction method of the embodiment to generate the reconstructed block for the target block.

Hereinafter, the processing unit may correspond to the processing unit 1210 of the encoding device 1200 and / or the processing unit 1310 of the decryption device 1300. [

In step 1410, the processing unit may generate a plurality of divided blocks by dividing the object block.

The processing unit may generate a plurality of divided blocks by dividing the target block using coding parameters associated with the target block.

In one embodiment, the processing unit may generate a plurality of divided blocks by dividing the object block based on at least one of the size of the object block and the shape of the object block.

For example, the target block may include a plurality of divided blocks. The plurality of divided blocks may be referred to as a plurality of sub-blocks.

An example of step 1410 is described in detail below with reference to FIG.

In one embodiment, whether to perform step 1410, i.e., whether to split a target block to generate a plurality of divided blocks, may be determined by information associated with a target block. The processor can determine whether to apply the partitioning of the target block based on the information related to the target block.

In one embodiment, the information related to the target block includes coding parameters for the target block, information related to the picture of the target picture including the target block, information related to the slice including the target block, and quantization parameters of the target block. QP), the coded block flag (CBF) of the target block, the size of the target block, the depth of the target block, the type of the target block, the entropy encoding method of the target block, A temporal layer level of the block, and a block partition indicator.

The reference block may include one or more blocks spatially adjacent to the target block and blocks temporally adjacent to the target block.

1) In one embodiment, the processing section can determine whether or not to apply the division of the target block according to the information related to the picture of the target picture. For example, the picture parameter set (PPS) of the target picture may include information indicating whether or not the block of the target picture is divided. Information indicating whether the block of the target picture is divided through the PPS can be encoded and / or decoded. Alternatively, a picture set to divide a block through PPS or a picture set not to divide a block may be identified.

For example, when the non-square target block is included in a picture designated to divide the block, the processing unit may divide the non-square target block into blocks of a square shape.

2) In one embodiment, the processing unit may determine whether to apply the partitioning of the target block based on the information of the specified picture. For example, the specified picture may be the previous picture of the target picture.

For example, the processing unit can determine whether or not the division of the target block is applied, depending on whether or not the division is applied to the block of the previous picture of the target picture.

For example, when the non-square block in the previous picture of the current picture is divided into blocks of the square shape, the processing unit may convert the non-square target block of the current picture into a square block . ≪ / RTI >

3) In one embodiment, the processing unit may determine whether to apply the partitioning of the object block based on the information of the slice. The slice may contain a target block. Alternatively, the slice may include a reference block.

For example, the processing unit can determine whether or not to apply the division of the target block according to the type of the slice. The type of slice may include I slice, B slice, and P slice.

For example, when the non-square target block is included in the I-slice, the processing unit may divide the non-square target block of the target picture into blocks of a square shape.

For example, when the non-square target block is included in the P slice or B slice, the processing unit may divide the target block in the non-square form into blocks in the form of a square.

4) In one embodiment, the processing unit may determine whether to apply the partitioning of the target block based on information of the other slice.

For example, the other slice may be a previous slice or a subsequent slice of the slice containing the target block. The other slice may be a slice containing a reference block of the target block.

For example, the processing unit can determine whether or not to apply the division of the target block according to the type of another slice. The type of the other slice may include an I slice, a B slice, and a P slice.

For example, when the other slice is an I-slice, the processing unit may divide the non-square target block of the target picture into blocks of the square shape.

For example, when the other slice is a P slice or a B slice, the processing unit may divide the non-square target block into blocks of a square shape.

5) In one embodiment, the processing unit may determine whether to apply segmentation of a target block based on a quantization parameter of the target block.

For example, if the quantization parameter of the non-square target block is within a specified range, the processing unit may divide the non-square target block into blocks of a square shape.

6) In one embodiment, the processing unit may determine whether to apply the partitioning of the object block based on the CBF of the object block.

For example, when the CBF of the non-square target block is equal to or corresponds to a specified value, the processing unit divides the non-square target block into blocks of a square shape can do.

7) In one embodiment, the processing unit may determine whether to apply segmentation of the object block based on the size of the object block.

For example, if the size of the non-square target block is equal to 1) the specified size, or 2) within the specified range, the processing unit may convert the non-square target block into blocks of a square shape Can be divided.

For example, the processing unit may determine that the sum of the length and the length of the non-square target block is equal to 1) the specified value, 2) the specified value is greater than or equal to 3) ) If it is within the specified range, the target block in the form of a non-square can be divided into blocks in the form of a square. For example, the specified value may be 16.

8) In one embodiment, the processing unit may determine whether to apply the partitioning of the object block based on the depth of the object block.

For example, if the depth of the target block in the non-square form is equal to 1) the specified depth, or 2) within the specified range, the processing unit may divide the non-square target block into blocks of a square shape Can be divided.

9) In one embodiment, the processor may determine whether to apply the partitioning of the object block based on the shape of the object block.

For example, if the ratio of the length to the length of the target block in the non-square form is equal to 1) the specified value or 2) within the specified range, the processing unit may set the target block in the non- Lt; RTI ID = 0.0 > of < / RTI >

10) In one embodiment, the processing unit may determine whether to apply segmentation of the target block based on the block segmentation indicator.

The block division indicator may be an indicator indicating whether or not the target block is divided. In addition, the block partitioning indicator may indicate the type of partitioning of the block.

The type of partition may include the direction of the partition. The direction of the division may be vertical or horizontal.

The type of partitioning may include the number of partitioned blocks created by partitioning.

In the embodiments, the indicator may be information that is explicitly signaled from the encoding device 1200 to the decoding device 1300 via the bitstream. In one embodiment, the indicator may comprise a block partition indicator.

When the block division indicator is used, the decoding apparatus 1300 can directly determine whether or not the target block is divided and the type of division directly with the block division indicator provided from the encoding apparatus 1200. [

The block partition indicator may be optional. When the block division indicator is not used, the processing unit can determine whether or not the object block is partitioned and the type of partition according to the condition using the information related to the object block. Thus, whether or not to partition the target block can be determined without signaling additional information.

For example, if the block division indicator indicates that the target block is to be divided, the processing unit may divide the non-square target block into blocks of a square shape.

The block segmentation indicator may be encoded and / or decoded for at least one unit of SPS, PPS, slice header, tile header, CTU, CU, PU and TU. In other words, the unit in which the block segmentation indicator is provided may be at least one of SPS, PPS, slice header, tile header, CTU, CU, PU and TU. The block division indicator provided for the specified unit may be commonly applied to one or more target blocks included in the specified unit.

11) In one embodiment, the processing unit may determine whether to apply the partitioning of the target block based on the information of the partitioning of the reference block.

The reference block may be a spatial adjacent block and / or a temporally adjacent block.

For example, the partition information may be at least one of quad-tree partition information, binary-tree partition information, and quad-tree plus binary-tree information.

For example, if the information of the division of the reference block indicates that the target block is divided, the processing unit may divide the non-square target block into blocks of the square shape.

12) In one embodiment, the processing unit may determine whether to apply the partitioning of the object block based on the temporal layer level of the object block.

For example, when the temporal layer level of the target block in the non-square form is equal to 1) specified value or 2) within the specified range, the processing unit sets the target block in the form of a non- . ≪ / RTI >

13) Further, in one embodiment, the information related to the target block may further include information used for coding and / or decoding the above-mentioned target block.

In the above-described embodiments 1) to 13), the specified value, the specified range, and / or the specified unit may be determined by the encoding apparatus 1200 or the decryption apparatus 1300. [ If the specified value, the specified range, and the specified unit are determined by the encoding apparatus 1200, the determined specific value, the determined specific range, and / or the determined specific unit are decoded from the encoding apparatus 1200 through the bit stream May be signaled to device 1300.

Alternatively, the specified value, the specified range, and / or the specified unit may be derived by other coding parameters. When the coding parameters can be shared between the encoding apparatus 1200 and the decoding apparatus 1300 via the bit stream or can be derived similarly from the encoding apparatus 1200 and the decoding apparatus 1300 by the predetermined derivation scheme, The specified value, the specified range, and / or the specified unit may not be signaled from the encoding device 1200 to the decryption device 1300.

In the above-described embodiments 1) to 13), whether the division of the target block is divided or not is determined by the criterion of the type of the target block is merely an example. Whether or not the target block is divided in the above-described embodiments 1) through 13) can be combined with other criteria described in the embodiment, such as the size of the target block.

In step 1420, the processing unit may derive a prediction mode for at least some of the plurality of divided blocks.

In one embodiment, the prediction may be intra prediction or inter prediction.

An example of step 1420 will be described in detail below with reference to FIG.

In step 1430, the processing unit may perform predictions for a plurality of segmented blocks based on the derived prediction mode.

In one embodiment, the processing unit may perform prediction for at least some of the plurality of divided blocks using the derived prediction mode. The processor may perform prediction on the remaining blocks of the plurality of divided blocks using the generated prediction mode based on the derived prediction mode.

The prediction of the divided blocks will be described below with reference to Figs. 22, 23, 24, 25, 26, 27, and 28. Fig.

15 is a flowchart of a block partitioning method according to an embodiment.

The block partitioning method of the embodiment may correspond to the step 1410 described above. Step 1410 may include at least one of steps 1510 and 1520. [

In step 1410, the processing unit may generate a plurality of divided blocks by dividing the object block based on at least one of the size of the object block and the shape of the object block.

The size of the target block may mean the width of the target block and / or the length of the target block.

The shape of the target block may indicate whether the target block is a square or not. The shape of the target block may indicate whether the target block is a square or a non-square. The shape of the target block may be a ratio of the length of the target block to the length of the target block.

The processing unit may generate a plurality of divided blocks by dividing the object block using at least one of the selection method of the prediction mode of step 1510 and the selection method of the prediction mode of step 1520. [

In step 1510, the processing unit may generate a plurality of divided blocks by dividing the object block based on the horizontal length or the vertical length of the object block.

In one embodiment, the processing unit may perform partitioning of a target block when the length and the length of the target block are different from each other.

In one embodiment, the processing unit may partition the greater of the transverse length and the longitudinal length of the object block at least once.

In one embodiment, the processing unit may partition the target block such that the width and height of the divided blocks are the same. Alternatively, the horizontal length and the vertical length of the divided blocks generated by the division may be larger than the shorter one of the horizontal length and the vertical length of the target block.

Examples of the target block and the division of the target block based on the length are illustrated with reference to FIGS. 16, 17, 18, 19 and 20 below.

In one embodiment, the processing unit may partition the target block when the size of the target block is smaller than the specified size, and the width and height of the target block are different.

In one embodiment, the processing unit can divide the target block when the sum of the width and height of the target block is smaller than the specified value, and the width and height of the target block are different from each other.

In one embodiment, the processing unit can divide the target block when the size of the target block is included in the specified range, and the width and the length of the target block are different from each other.

In step 1520, the processing unit may generate a plurality of divided blocks by dividing the object block based on the type of the object block.

The processing unit may not divide the target block when the shape of the target block is a square.

The processing unit may divide the target block into a square shape when the shape of the target block is non-square. The division in the form of a square is illustrated with reference to Figs. 16, 17, 18 and 20 below.

As described above in step 1510 and step 1520, the processor uses only the size of the target block and the shape of the target block in determining whether or not the target block is divided, It may not be used. Therefore, information indicating whether or not the block is divided may not be signaled from the encoder 1200 to the decoder 1300, and whether or not the block is divided may be derived based on the size and / or type of the target block.

16 shows an 8x4 target block according to an example.

In Fig. 17, the division into the target block is described.

17 shows divided blocks of 4x4 size according to an example.

The size of each of the first divided block and the second divided block may be 4x4.

As shown in FIG. 17, when the length of the horizontal length of the object block is larger than the vertical length, two divided blocks can be derived by vertically dividing the horizontal length of the object block shown in FIG.

18 shows a 4x16 target block according to an example.

In Fig. 19 and Fig. 20, the division into the target block is described.

FIG. 19 shows divided blocks of 8x4 size according to an example.

The size of each of the first divided block and the second divided block may be 8x4.

FIG. 20 shows divided blocks of 4x4 size according to an example.

The size of each of the first divided block, the second divided block, the third divided block, and the fourth divided block may be 4x4.

As shown in Figs. 19 and 20, when the length of the object block is longer than the length of the width, the length of the object block shown in Fig. 18 is horizontally divided into two divided blocks or 4 Divided blocks can be derived.

21 is a flowchart of a method of deriving a prediction mode for a divided block according to an example.

The method of deriving the prediction mode of the embodiment may correspond to the step 1420 described above. Step 1420 may include at least one of steps 2110, 2120 and 2130. [

For each of the plurality of divided blocks generated by the division of the target block, 1) prediction modes for a plurality of divided blocks may be respectively derived, and 2) one of the plurality of divided blocks And 3) a prediction mode common to all of the plurality of divided blocks can be derived.

Depending on the subject of the derived prediction mode, at least one of steps 2110, 2120 and 2130 may be performed.

In step 2110, the processing unit may derive prediction modes for the plurality of divided blocks, respectively.

The processing unit may derive a prediction mode for each of the plurality of divided blocks using the method of deriving the prediction mode described above in the embodiments.

In step 2120, the processing unit may derive a prediction mode for the specified divided block of the plurality of divided blocks.

The specified divided block may be a block of a specified one of the plurality of divided blocks.

For example, the specified divided block is the uppermost block, the lowermost block, the leftmost block, the rightmost block, the nth block at the top, the nth block at the bottom, May be one or more of the n-th block in the right side and the n-th block in the right side. n may be an integer equal to or greater than 1 and equal to or less than the number of divided blocks.

In one embodiment, the processing unit may derive a prediction mode for the specified divided block of the plurality of divided blocks using the above-described derivation method of the prediction mode in the embodiments.

In one embodiment, the derived prediction mode may be used for the remaining blocks excluding the divided blocks specified from among the plurality of divided blocks. The processing unit may use the derived prediction mode for the remaining blocks excluding the specified divided block among the plurality of divided blocks.

In one embodiment, a combination of the derived prediction mode and another prediction mode may be used for the remaining blocks excluding the divided blocks specified from among the plurality of divided blocks. The processing unit may use a prediction mode determined by a combination of the prediction mode derived from the other prediction modes and the prediction mode for the remaining blocks excluding the specified divided block among the plurality of divided blocks.

For example, another prediction mode may be determined using coding parameters associated with each remaining block of remaining blocks. The processor may determine an additional prediction mode using the coding parameters associated with the remaining blocks and determine a prediction mode for the remaining blocks using a combination of the derived prediction mode and the additional prediction mode for the specified block You can decide.

For example, the combination of prediction modes may be a prediction mode indicating the direction between the directions of the prediction modes. The combination of prediction modes may be a prediction mode selected by a specified one of the prediction modes. The prediction mode determined using a combination of prediction modes may be different from each of the prediction modes used for combination.

In step 2130, the processing unit may derive a prediction mode common to all of the plurality of divided blocks. That is to say, one prediction mode common to a plurality of divided blocks can be derived.

For example, the processing unit may derive a prediction mode common to all of the divided blocks using coding parameters common to all of the plurality of divided blocks.

Derivation of prediction mode using Most Probable Mode (MPM)

In deriving the prediction mode of the above-described divided block, the processing unit can use the MPM.

To use the MPM, the processing unit can construct an MPM list.

The MPM list may include one or more MPM candidate modes. One or more MPM candidate modes may be N. N may be a positive integer.

In one embodiment, the processing unit may determine the value of N according to the size and / or shape of the object block. Alternatively, the processing unit may determine the value of N according to the size, shape, and / or number of the divided blocks.

Each MPM candidate mode of one or more MPM candidate modes may be an intra prediction mode of one of the predetermined intra prediction modes.

The processing unit may configure one or more MPM candidate modes of the MPM list based on one or more prediction modes of one or more reference blocks of the target block. The reference block may be a block at a predetermined location and may be a block adjacent to the target block. For example, one or more reference blocks may be blocks adjacent to the top of the target block and blocks adjacent to the left of the target block.

The one or more MPM candidate modes may be one or more prediction modes determined based on the prediction modes of the reference blocks. The processor may determine one or more prediction modes as one or more MPM candidate modes by referring to prediction modes of one or more reference blocks. In other words, one or more MPM candidate modes may be a prediction mode with a high probability of being a prediction mode of a target block. This probability may be calculated by experiments or the like. For example, it is known that there is a high likelihood that the prediction mode of the reference block will be used as the prediction mode of the target mode due to the local association between the reference block and the target block. Thus, the prediction mode of the reference block may be included in one or more MPM candidate modes.

In one embodiment, the MPM list may be one or more, or multiple. For example, the number of MPM lists may be M. M may be a positive integer. The processor may configure each MPM list of the plurality of MPM lists using different methods.

For example, the processing unit may configure the first MPM list, the second MPM list, and the third MPM list.

The MPM candidate modes in one or more MPM lists may be different. Alternatively, the MPM candidate modes of one or more MPM lists may not overlap each other. For example, when a specified intra prediction mode is included in one MPM list, a plurality of MPM lists may be configured such that the specified intra prediction mode is not included in another MPM list.

An MPM list indicator may be used to specify an MPM list that includes a prediction mode used for encoding and / or decoding of a target block among one or more MPM lists. That is, the MPM list indicated by the MPM list indicator among the one or more MPM lists can be specified, and the processor can use one MPM candidate among the one or more MPM candidate modes of the specified MPM list for prediction on the target block.

The MPM list indicator may be signaled from the encoder 1200 to the decoder 1300 via a bitstream.

When the MPM list indicator is used, the decryption apparatus 1300 determines whether the MPM candidate mode of one of the one or more lists is to be used for prediction of the target block, directly to the MPM list indicator provided from the encoding apparatus 1200 Can be determined.

In one implementation, the MPM usage indicator may indicate whether to determine the prediction mode using the MPM list.

The MPM usage indicator may indicate whether a prediction mode of the target block is present among one or more MPM candidate modes in the configured MPM list.

If the MPM usage indicator indicates that there is a prediction mode of the target block among the one or more MPM candidate modes, the processing unit may use the index indicator to determine the prediction mode of the target block from among the one or more MPM candidate modes.

The index indicator may indicate an MPM candidate mode to be used for prediction of a target block among one or more MPM candidate modes of the MPM list. The processor may determine the MPM candidate mode indicated by the index indicator among one or more MPM candidate modes of the MPM list as a prediction mode of the target block. The index indicator can also be named as an MPM index.

If one of the one or more MPM candidate modes of the MPM list indicated by the MPM list is used for predicting the target block when the MPM list is indicated by the MPM list indicator among the one or more MPM lists, An index indicator may be used to indicate that. That is to say, the prediction mode of the target block can be specified by the MPM list indicator and the index indicator.

If the MPM usage indicator indicates that there is no prediction mode of the target block among the one or more MPM candidate modes of the MPM list, the processing unit may determine the prediction mode of the target block using the prediction mode indicator indicating the prediction mode of the target block have. The prediction mode indicator may indicate the prediction mode of the target block.

The prediction mode indicator may indicate one of the prediction modes not included in the MPM list (or one or more MPM lists). That is to say, one or more prediction modes not included in the MPM list or one or more MPM lists may be configured as a prediction mode list in the predetermined order, and the prediction mode indicator may be one of one or more prediction modes of the prediction mode list Mode.

The one or more prediction modes of the prediction mode list may be sorted in ascending or descending order. Here, the criterion of the alignment may be the number of the prediction mode.

When there are a plurality of MPM lists, a separate MPM use indicator may be used for each of the plurality of MPM lists. Alternatively, when there are a plurality of MPM lists, there may be an MPM usage indicator for some of the plurality of MPM lists.

For example, the n-th MPM usage indicator for the n-th MPM list may indicate whether a prediction mode of the target block exists in the n-th MPM list.

First, the processor can determine whether a prediction mode of the target block exists in the first MPM list using the first MPM use indicator. When the prediction mode of the target block exists in the first MPM list, the processor can derive the MPM candidate mode indicated by the index indicator in the first MPM list as the prediction mode of the target block. If the prediction mode of the target block does not exist in the first MPM list, the processor may determine whether a prediction mode of the target block exists in the second MPM list using the second MPM use indicator.

The processor may determine whether a prediction mode of the target block exists in the nth MPM list using the nth MPM use indicator. If there is a prediction mode of the target block in the nth MPM list, the processor may use the index indicator to determine the MPM candidate mode indicating the prediction mode of the target block in the nth MPM list. If the prediction mode of the target block does not exist in the first MPM list, the processing unit can determine whether or not the prediction mode of the target block exists in the (n + 1) th MPM list using the following (n + 1) have.

If one MPM usage indicator indicates that there is a prediction mode of the target block in the MPM list, the next MPM usage indicators of the MPM usage indicator of the commercial MPM usage indicator may not be signaled.

The MPM usage indicator, the index indicator, and / or the prediction mode indicator may be signaled from the encoding device 1200 to the decoding device 1300 via a bitstream.

If an MPM usage indicator, an index indicator, and / or a prediction mode indicator are used, then the decoding apparatus 1300 may be configured to 1) select one or more MPM candidate modes of one or more MPM lists, and 2) , Which MPM candidate mode or prediction mode is to be used for prediction of the target block, can be directly determined by the MPM usage indicator, the index indicator, and / or the prediction mode indicator provided from the encoding apparatus 1200.

The MPM list can be configured for a specified unit.

In one embodiment, the specified unit may be a block of a specified size or a target block.

When the specified unit is divided, the processing unit can use the configured MPM list for prediction of the plurality of divided blocks generated by the division.

In one embodiment, when the size of the target block corresponds to a specified size or the same size as the specified size, the processing unit may construct an MPM list for the target block. When the target block is divided into a plurality of divided blocks, the processing unit may derive a prediction mode of each divided block of the plurality of divided blocks using the MPM list configured for the target block.

For example, when the size of the target block is 8x8 and the divided blocks are four 4x4 blocks, an MPM list for 8x8 blocks can be constructed, and for each of the 4x4 blocks, An MPM list can be used.

In one embodiment, in constructing the MPM list, the processing unit may construct an MPM list for each of the divided blocks in a block of a specified size based on a block of a specified size. That is, the MPM list generated for a block of a specified size can be commonly used for the divided blocks.

For example, if the size of the target block is the specified size, the MPM list for each partitioned block in the target block may be determined using the prediction modes of one or more reference blocks of the target block (rather than the partitioned block) Lt; / RTI >

For example, if the size of the target block is 8x8, and the divided blocks are four 4x4 blocks, the processor extracts the MPM lists for the four divided blocks based on one or more reference blocks of the target block Can be configured. In this case, since the prediction mode of the reference block of the target block is already obtained, the processor can construct the MPM lists for the four divided blocks in parallel.

Figure 22 shows a prediction for a partitioned block according to an example.

In Fig. 22, the first block may be a specific one of the divided blocks. For example, the first block may be a block in which prediction is first performed among the divided blocks.

The processor may derive a prediction mode for the first block in the prediction for the first block.

As shown in FIG. 22, the processing unit may use the reference samples adjacent to the first block in the prediction for the first block. Alternatively, the reference samples may be pixels around the first block. The reference samples may be pixels of the reconstructed block adjacent to the first block.

23 shows a prediction for a partitioned block using a reconstructed block of a partitioned block according to an example.

In Fig. 23, the second block may be a specific one of the divided blocks. For example, the second block may be a block in which 2) prediction is performed, 2) a block in which prediction is performed last, and 3) a prediction is performed in the next prediction in the first block Block 4) a block for which prediction is to be performed after the prediction for the first block, or 5) a block for which prediction is performed after the prediction for at least one divided block.

As described above, in the prediction for the second block, the processing unit can use the prediction mode derived for the first block.

As shown in FIG. 22, the processing unit may use the reference samples adjacent to the second block in the prediction for the second block.

The reference samples may be pixels of the reconstructed block adjacent to the second block. The reference samples may comprise reconstructed pixels of the reconstructed block of the first block.

Alternatively, the reference samples may comprise reconstructed pixels of the reconstructed block of another segmented block predicted prior to the prediction for the second block. That is to say, in the prediction for the second block, another divided block predicted before the prediction for the second block among the plurality of divided blocks may be used.

Figure 24 shows a prediction for a partitioned block using reference pixels outside the partitioned block according to an example.

The processor may use a pixel outside the plurality of divided blocks as a reference sample in prediction for the divided block. That is to say, in the prediction of the divided block, the processing unit can exclude the pixels inside the plurality of divided blocks from the reference sample. The pixels excluded from the reference sample are either 1) replaced with the closest pixel in the same direction as the excluded pixel direction, or 2) replaced with the pixel adjacent to the target block in the same direction as the excluded pixel direction .

In one embodiment, for predictions of a plurality of segmented blocks, the reference samples used for the predictions may be reconstructed pixels adjacent to the target block (rather than each segmented block).

For example, as shown in FIG. 24, in the prediction for the second block, the processing unit may exclude the pixels in the reconstructed block of the first block from the reference sample, Pixels can be used as reference samples.

For example, the processing unit may use the reconstructed pixel adjacent to the target block as reference samples for prediction of each divided block of the plurality of divided blocks generated by the segmentation of the target block. Through the determination of this reference sample, the values of all reference samples used for predictions of the plurality of divided blocks can be determined prior to the prediction of the plurality of divided blocks. Thus, the processor may determine the values of all reference samples used for predictions of the plurality of divided blocks, prior to the predictions of the plurality of divided blocks, and may perform predictions of the plurality of divided blocks in parallel .

25 shows prediction of four divided blocks according to an example.

As shown in Fig. 25, four divided blocks of the first block, the second block, the third block and the fourth block can be generated by dividing the target block.

As described above, the processing unit can derive a prediction mode for a specified divided block among a plurality of divided blocks.

In Fig. 25, the prediction mode can be derived for the fourth block, which is an example of the lowermost block. The derived prediction mode may be used for the first blocks, the second blocks, and the third blocks, which are the remaining blocks.

The processing unit may preferentially perform prediction on a specified divided block from which a prediction mode of a plurality of divided blocks is derived. Next, the processing unit may perform the prediction using the prediction mode derived for the remaining blocks excluding the specified block among the plurality of blocks.

The processor may use the reconstructed pixels around the specified segmented block and / or the target block as reference samples in predicting the specified segmented block from which the prediction mode is derived.

According to Fig. 25, at the time of prediction for the fourth block, there may be no reconstructed pixels adjacent to the top of the fourth block. Thus, in the prediction for the fourth block, the processing unit can use reconstructed pixels adjacent to the top of the target block as reference pixels.

The processing unit may perform predictions of a plurality of divided blocks in a predetermined order. The default order may be different from the order for generic blocks that are not created by partitioning. For example, the predetermined order may be 1) order from the bottom-most block to the top-most block, or 2) order from the right-most block to the left-most block. Alternatively, the predetermined order may be 3) the order in which the bottom-most block is first selected, then sequentially from the bottom-most block to the second-most block, or 4) And then sequentially selected from the rightmost to the second block from the leftmost block.

Alternatively, the predetermined order may be arbitrarily determined by the encoding apparatus 1200 and / or the decoding apparatus 1300. [ When the predetermined order is determined by the encoding apparatus 1200, the determined default order can be signaled from the encoding apparatus 1200 to the decryption apparatus 1300. [

The prediction order indicator may indicate an order of predictions for a plurality of segmented blocks. The encoding apparatus 1200 can determine the value of the prediction order indicator. The prediction order indicator may be signaled from the encoding apparatus 1200 to the decoding apparatus 1300 through a bit stream.

Alternatively, the predetermined order may be derived in accordance with the same predetermined method in each of the encoding apparatus 1200 and / or the decryption apparatus 1300. The processor may derive a predetermined order using coding parameters or the like associated with the object block.

FIG. 26 shows a prediction for the first block after the prediction for the fourth block according to an example is performed.

As described above, in performing predictions of a plurality of divided blocks, a predetermined order can be used.

The predefined order illustrated in FIG. 26 is that the predictions for the lowermost block among the plurality of divided blocks are performed first, then sequentially from the highest block to the second block from top to bottom, Lt; / RTI > may be performed. In the order of the embodiment, the "bottom-most" may be replaced with "rightmost"

Since the predictions of the plurality of divided blocks are performed in the predetermined order, additional reference samples become available as compared to performing predictions of the plurality of divided blocks according to the existing order, as shown in Fig. . Thus, other directional intra prediction using reference samples that are more available than normal intra prediction can be used.

The processing unit may use the pixels of the reconstructed block of the previously predicted divided block of the prediction for each of the divided blocks in the prediction of each divided block of the plurality of divided blocks as the reference samples have.

For example, as shown in Fig. 26, in the prediction for the first block, the processing unit can use the pixels of the reconstructed block of the previously predicted fourth block as reference samples.

Depending on the use of this predefined sequence and the use of pixels of the reconstructed block of previously predicted segmented blocks, the reference samples in more directions Can be provided. For example, as shown in FIG. 26, reference samples located below the first block may be provided.

In one embodiment, the processor may perform intra prediction using the reference samples adjacent to the bottom of the segmented block for prediction of the segmented block, and may perform intra prediction using intra samples using adjacent reference samples to the right of the segmented block Prediction can be performed.

For example, reference samples adjacent to the bottom of a segmented block may be copied in the prediction block in an upward, left upward and / or rightward upward direction. The reference samples adjacent to the right side of the divided block may be copied in the prediction block in the leftward, leftward upward, and / or leftward and downward directions.

FIG. 27 shows a prediction for a second block according to an example.

The prediction for the second block may be performed after the prediction for the fourth block and the prediction for the first block. Thus, as described above, the pixels of the reconstructed block of the fourth block and the pixels of the reconstructed block of the first block may be included as reference samples used in the prediction for the second block.

That is to say, the processing unit can use the pixels of the reconstructed blocks of other divided blocks as reference samples in performing the prediction for the specified divided block among the plurality of divided blocks. Here, the other divided blocks may be blocks that have been predicted previously of the prediction for the specified divided block among the plurality of divided blocks.

Alternatively, if prediction for the third block is earlier than prediction for the second block, the reference samples shown in FIG. 27 may be used for prediction for the third block.

FIG. 28 shows a prediction for the third block according to the work.

The prediction for the third block may be performed last after the prediction for the fourth block, the prediction for the first block, and the prediction for the second block.

FIG. 28 may show reference samples available in the prediction for the third block.

In one embodiment, for a partitioned block, a reference sample type to be used for prediction of a partitioned block among a plurality of reference sample types may be selected.

For example, in the prediction for the third block, the processing unit may compare the reference samples shown in Fig. 25, the reference samples shown in Fig. 26, the reference samples shown in Fig. 27, and the reference samples Can be used.

The processing unit may use reference samples according to one of the plurality of reference sample types in performing the prediction for the specified divided block.

The plurality of reference sample types may include a first reference sample type, a second reference sample type, and a third reference sample type.

The reference samples of the first reference sample type may be reconstructed pixels adjacent to the target block. That is to say, the reference samples of the first reference sample type may be the reference samples shown in FIG.

The reference samples of the second reference sample type may be the reference samples of the first reference sample type and the pixels of the reconstructed block of the previously partitioned block on which prediction has been performed. That is to say, the reference samples of the second reference sample type may be the reference samples shown in FIG. 26 or FIG.

In one embodiment, the pixels of the reconstructed block of the previously segmented block may be used for directions that are not covered by reconstructed pixels adjacent to the target block. That is to say, the reconstructed pixels adjacent to the target block may be used in preference to the pixels of the reconstructed block of the partitioned block. (For example, the reference samples shown in Fig. 26)

Alternatively, in one embodiment, the pixels of the reconstructed block of the previously segmented block that have been previously predicted may replace at least some of the reconstructed pixels adjacent to the target block. (E. G., The reference samples shown in FIG. 27)

That is to say, the pixels of the reconstructed block of the divided block can be used more preferentially than the reconstructed pixels adjacent to the target block.

That is, since the pixels of the reconstructed block of the previously segmented predicted block are closer to the specified segmented block than the reconstructed samples adjacent to the target block, The pixels of the constructed block may be used for prediction on a specified divided block (instead of the reconstructed pixels adjacent to the target block), and the reconstructed pixels adjacent to the target block may be used for prediction of the previously- Lt; RTI ID = 0.0 > of blocks < / RTI > of the reconstructed block.

Reference samples of the third reference sample type may be reconstructed pixels adjacent to a specified segmented block. That is to say, the reference samples of the third reference sample type may be the reference samples shown in FIG.

In one embodiment, the processing unit may use the information associated with the object block or the partitioned block to determine reference samples to be used in the prediction for the partitioned block.

In one embodiment, the processing unit may determine reference samples to be used in the prediction for the partitioned block based on the reference sample indicator.

The reference sample indicator may be an indicator that indicates reference samples to be used in the prediction for the block. The reference sample indicator may indicate a reference sample type to be used in the prediction for the block among the plurality of reference sample types.

The processing unit may determine the value of the reference sample indicator.

The reference sample indicator may be signaled from the encoding device 1200 to the decoding device 1300 via a bitstream. Alternatively, coding parameters associated with a reference block or a partitioned block may be used to at least partially determine the reference sample indicator.

If a reference sample indicator is used, in the decoding apparatus 1300, reference samples to be used for prediction on the divided block can be directly determined by the reference sample indicator provided from the encoding apparatus 1200. [

Filtering for reference samples

Prior to the prediction described above, the processing unit may perform filtering on the reference samples and may determine whether to perform filtering on the reference samples.

In one embodiment, the processing unit may determine whether to perform filtering on the reference samples based on the size and / or shape of the target block.

In one embodiment, the processing unit may determine whether to perform filtering on the reference samples based on the size and / or shape of the partitioned block.

In one embodiment, the processing unit may determine whether to perform filtering on the reference samples, depending on whether the reconstructed block adjacent to the target block is used as a reference block of the divided block.

In one embodiment, the processing unit may determine whether to perform filtering on the reference samples, depending on whether or not to perform predictions of the partitioned blocks in parallel.

Alternatively, in one embodiment, the processing unit may determine whether to perform filtering on the reference samples, depending on whether the specified function, operation, and processing described in the embodiment are performed.

Alternatively, in one embodiment, the processing unit may determine whether to perform filtering on the reference samples based on coding parameters associated with the object block or coding parameters associated with the partitioned block.

29 is a flowchart of a prediction method according to an embodiment.

In the embodiment described above with reference to FIG. 14, a plurality of divided blocks are generated by dividing the object block in step 1410, and in step 1420, for at least some of the prediction modes of the plurality of divided blocks It has been described that a prediction mode is derived.

In this embodiment, a plurality of divided blocks may be generated by dividing the target block after the first prediction mode is derived.

In step 2910, the processing unit may derive a prediction mode.

For example, the derived prediction mode may be a prediction mode for the target block. The processing unit may derive the prediction mode according to a scheme for deriving the prediction mode for the object block described above.

For example, the derived prediction mode may be a prediction mode used for predictions of a plurality of segmented blocks generated by segmentation of a target block, when segmentation for a target block is performed. That is to say, the derived prediction mode may be a prediction mode used when the target block is divided.

In one embodiment, the derived prediction mode may be multiple.

For example, a plurality of derived prediction modes may be used for predictions of a plurality of divided blocks generated by partitioning a target block, respectively.

The explanation related to the derivation of the prediction mode of the divided block in the above-described embodiment can also be applied to the derivation of the prediction mode of this embodiment. For example, MPM can be used in the derivation of the prediction mode. Duplicate descriptions are omitted.

In step 2920, the processing unit may generate a plurality of divided blocks by dividing the object block.

A description related to the division of the object block described above with reference to step 1410 and the like may also be applied to step 2920. [ Duplicate descriptions are omitted.

In step 2930, the processing unit may perform prediction on at least some of the plurality of divided blocks using the derived prediction mode.

A description relating to prediction of at least some of the plurality of divided blocks described above with reference to step 1430 and the like may be applied to step 2930 as well. However, in the description with reference to the steps 1420 and 1430, a prediction mode is derived for a specific divided block among a plurality of divided blocks, and for the remaining blocks excluding the specified divided block, The predicted mode determined based on the derived prediction mode or the derived prediction mode described above is used for the block to be predicted. This description assumes that a prediction mode is derived in step 2910 and a prediction mode determined based on the prediction mode derived in step 2910 or the derived prediction mode is used for a plurality of divided blocks . Duplicate descriptions are omitted.

30 shows the derivation of a prediction mode for a target block according to an example.

As described above in the embodiment of FIG. 29, in step 2910, a prediction mode for the target block may be derived. If the prediction mode for the target block is derived, predictions for the first block and the second block may be performed using the derived prediction mode, similar to that described above with reference to Figures 22, 23 and 24. [

Alternatively, in step 2910, a plurality of prediction modes may be derived for the target block. A plurality of derived prediction modes may be used for prediction of the divided blocks, respectively.

The processing unit may determine which prediction mode among a plurality of derived prediction modes to use for prediction of a segmented block according to a method of using a coding parameter or the like related to the target block.

31 is a flowchart of a prediction method of a target block and a bitstream generation method according to an embodiment.

The prediction method and the bitstream generation method of the target block in the embodiment can be performed by the encoding apparatus 1200. [ The embodiment may be a part of a coding method or a video coding method of a target block.

In step 3110, the processing unit 1210 may perform the division of the block and the derivation of the prediction mode.

Step 3110 may correspond to steps 1410 and 1420 described above with reference to FIG. Step 3110 may correspond to steps 2910 and 2920 described above with reference to FIG.

In step 3120, the processing unit 1210 may perform prediction using the derived prediction mode.

Step 3120 may correspond to step 1430 described above with reference to FIG. Step 3120 may correspond to step 2930 described above with reference to FIG.

In step 3130, the processing unit 1210 may generate the prediction information. The prediction information may be generated, at least in part, in step 3110 or step 3120. [

The prediction information may be the information used for the division of the above-mentioned blocks and the derivation of the prediction mode. For example, the prediction information may include the indicators described above.

In step 3140, the processing unit 1210 may generate a bitstream.

The bitstream may include information on a coded target block. For example, the information on the encoded target block may include transformed and quantized coefficients of the target block and / or the divided block, and may include coding parameters of the target block and / or the divided block. The bitstream may include prediction information.

The processing unit 1210 can perform entropy encoding on the prediction information and generate a bitstream including the entropy-encoded prediction information.

The processing unit 1210 may store the generated bit stream in the storage 1240. Alternatively, the communication unit 1220 can transmit the bit stream to the decryption apparatus 1300. [

32 is a flowchart of a prediction method of a target block using a bitstream according to an embodiment.

The prediction method of the target block using the bitstream of the embodiment can be performed by the decoding apparatus 1300. [ The embodiment may be part of a decoding method or a video decoding method of a target block.

In step 3210, the communication unit 1320 can acquire the bit stream. The communication unit 1320 can receive the bit stream from the encoding device 1200. [

The bitstream may include information on a coded target block. For example, the information on the encoded target block may include transformed and quantized coefficients of the target block and / or the divided block, and may include coding parameters of the target block and / or the divided block. The bitstream may include prediction information.

The processing unit 1310 may store the obtained bitstream in the storage 1240.

In step 3220, the processing unit 1310 may obtain prediction information from the bitstream.

The processing unit 1310 can obtain prediction information by performing entropy decoding on the entropy-encoded prediction information of the bitstream.

At step 3230, the processing unit 1210 may use the prediction information to perform the division of the block and the derivation of the prediction mode.

Step 3230 may correspond to steps 1410 and 1420 described above with reference to FIG. Step 3230 may correspond to steps 2910 and 2920 described above with reference to FIG.

In step 3240, the processing unit 1210 may perform a prediction using the derived prediction mode.

Step 3240 may correspond to step 1430 described above with reference to FIG. Step 3240 may correspond to step 2930 described above with reference to FIG.

Partitioning of blocks using partitioning directives

In the above-described embodiment, it has been described that the target block is divided based on the size and / or shape of the target block.

In partitioning a block, a partitioning indicator may be used. The block division indicator may indicate whether to generate two or more divided blocks by dividing a block in coding and decoding a block and to use each divided block of the generated divided blocks as a unit of encoding and decoding .

The description related to the division of the blocks and the prediction of the blocks described in the above embodiments can be applied to the following embodiments as well.

In one embodiment, the block partition indicator may be a binary tree partition indicator indicating whether the block is to be partitioned in the form of a binary-tree. For example, the name of the binary tree segmentation indicator may be "binarytree_flag" or "BTsplitFlag".

Alternatively, the block partitioning indicator may be a quadtree partitioning indicator indicating whether to partition the block into a quad-tree.

In one embodiment, the first predetermined value of the values of the partitioning indicator may indicate that the block is not partitioned, and the second predetermined value may indicate partitioning the block.

If the partitioning indicator of the block has a first predetermined value, the processing unit may not split the block.

In one embodiment, if a partition indicator of a block exists and the partition indicator has a first predetermined value, the block may not be partitioned even if the block has a shape and a shape to which the partition is applied.

In one embodiment, if the segmentation indicator of the block has a second predetermined value, the processing unit may divide the block to generate segmented blocks, and may perform encoding and / or decoding on the segmented blocks have. If the block division indicator has a second predetermined value, the processing unit may divide the block to generate divided blocks, and the divided block may be re-divided by the shape and / or shape of the divided block, .

In one embodiment, the partition indicator of the target block may indicate whether or not the target block is partitioned with respect to the target block. In addition, the partition indicator of the upper block of the target block can indicate whether or not the upper block is divided. If the division indicator of the upper block indicates that the upper block is divided into a plurality of blocks, the processing unit may divide the upper block into a plurality of blocks including the target block. That is, in the embodiments, the above-described target block may also be regarded as a block generated by division by a division indicator or the like.

FIG. 33 shows the division of an upper block according to an example.

For example, if the value of the partitioning indicator of the upper block is the second predetermined value and the value of the partitioning indicator of the target block is the first predetermined value, the upper block is divided into a plurality of blocks including the target block And a plurality of blocks including the object block may be the object or unit of the specified processing of encoding and / or decoding, respectively.

34 shows the partitioning of an object block according to an example.

For example, when the value of the partition indicator of the upper block is the second predetermined value and the target block generated by the partitioning of the upper block has a size and / or a shape to which the partition is applied, Blocks. Each divided block of the plurality of divided blocks may be the object or unit of the specified processing of encoding and / or decoding.

Partitioning of blocks for transforming blocks etc.

In the above-described embodiment, the divided blocks are described as a unit of prediction. The divided blocks of the embodiment may be units of other processing in encoding and / or decoding other than prediction.

In the following embodiments, an embodiment is described in which a target block or a divided block is used as a unit of processing for prediction, conversion, quantization, inverse transform, inverse quantization, and the like in coding and / or decoding of a block.

35 is a signal flow diagram illustrating a method of encoding and decoding an image according to an embodiment.

In step 3510, the processing unit 1210 of the encoding apparatus 1200 may perform prediction associated with the target block.

In step 3520, the processing unit of the encoding apparatus 1200 may perform transformations related to the object block based on the prediction.

In step 3530, the processing unit 1210 of the encoding apparatus 1200 may generate a bitstream including the result of the transformation.

In step 3540, the communication unit 1220 of the encoding apparatus 1200 can transmit the bit stream to the communication unit 1320 of the decryption apparatus 1300.

In step 3550, the processing unit 1310 of the decoding apparatus 1300 can extract the result of the conversion.

In step 3560, the processing unit 1310 of the decoding apparatus 1300 may perform an inverse transformation related to the target block.

In step 3570, the processing unit of decoding apparatus 1300 may perform prediction associated with the object block (1310).

The specific features of the steps 3510, 3520, 3530, 3540, 3550, 3560 and 3570 and the specifics of the predictions, conversions and inversions at steps 3510, 3520, 3560 and 3570 are described in detail below do.

When the divided blocks are units of conversion and inverse conversion

In step 3510, the processing unit 1210 may generate a residual block for a target block by performing prediction on the target block.

In step 3520, the processing unit 1210 may perform the conversion on a divided block basis. That is to say, the processing unit 1210 can generate the divided residual blocks by dividing the residual block, and can perform the transform on each of the divided residual blocks to generate the coefficients of the divided block.

In the following, the transform can be interpreted as including quantization as well as transformation. The inverse transform includes inverse quantization, and can be interpreted as inverse transform. In addition, the coefficients can be interpreted as meaning transformed and quantized coefficients.

The result of the transform of step 3530 may include a plurality of coefficients of the divided blocks.

In step 3560, the processing unit 1310 may perform inverse transform of the divided block unit using the coefficients of the divided block. That is, the processing unit 1210 can generate the reconstructed divided residual block by performing an inverse transformation on the coefficients of the divided block.

The plurality of reconstructed divided residual blocks for the plurality of divided blocks may constitute a reconstructed residual block for the object block. Alternatively, the reconstructed residual block for the target block may include a plurality of reconstructed divided residual blocks.

In step 3570, the processing unit 1310 may generate a prediction block for the target block by performing prediction on the target block, and may generate the restored block by summing the prediction block and the reconstructed residual block. The reconstructed block may contain reconstructed samples.

In one embodiment, the TU segmentation indicator may indicate whether the transform and inverse transform are performed in units of the segmented block. For example, the name of the TU segmentation indicator may be "TUsplitFlag ".

The TU segmentation indicator may be signaled via a bitstream.

In one embodiment, when the value of the partition indicator of the upper block is the second predetermined value, the target block is divided into a plurality of divided blocks in the steps of the transformation and inverse transformation, and the transformation and inverse transformation Can be signaled by the TU segmentation indicator.

In one embodiment, if the value of the partitioning indicator of the upper block is the second predetermined value and the value of the partitioning indicator of the object block is the first predetermined value, It is divided into divided blocks, and it can be signaled by the TU segmentation indicator whether the transform and inverse transform are performed on the divided block.

In one embodiment, when the shape and / or shape of the target block is the shape and / or shape to which the segmentation is applied, the target block is divided into a plurality of segmented blocks in the steps of transformation and inverse transformation, It can be signaled by the TU segmentation indicator whether conversion and inverse transformation is to be performed.

Here, the shape and / or shape to which the segmentation is applied may be the shape and / or the shape described in the above-described another embodiment in which the segmentation of the target block is performed, for example, a non-square shape. Alternatively, the shape and / or shape to which the segmentation is applied may include the state and / or condition described in the above-described another embodiment as the segmentation of the target block. The same goes for the following.

In one embodiment, when the value of the partition indicator of the upper block is the second predetermined value, the target block may be divided into a plurality of divided blocks of a square in the steps of transform and inverse transform, Conversion and inverse transformation can be performed.

In one embodiment, if the value of the partitioning indicator of the upper block is the second predetermined value and the value of the partitioning indicator of the object block is the first predetermined value, It may be divided into a plurality of divided blocks, and the transform and inverse transform may be performed on the divided block.

In one embodiment, if the shape and / or shape of the object block is a shape and / or shape to which the segmentation is applied, the object block may be divided into a plurality of segmented blocks in the steps of transformation and inverse transformation, Conversion and inverse transform can be performed on the block.

When the divided blocks are a unit of conversion, inverse conversion, and prediction

In step 3510, the processing unit 1210 may perform prediction on a divided block basis. That is, the processing unit 1210 can generate a divided residual block for the divided block by performing prediction on the divided block.

In one embodiment, the prediction may be intra prediction.

In step 3520, the processing unit 1210 may perform the conversion on a divided block basis. That is, the processing unit 1210 may perform the transform on the divided residual block to generate the coefficients of the divided block.

The result of the transform of step 3530 may include a plurality of coefficients of the divided blocks.

In step 3560, the processing unit 1310 may perform inverse transform of the divided block unit. In other words, the processing unit 1210 can generate the reconstructed divided residual block by performing inverse transformation on the coefficients of the divided residual block.

In step 3570, the processing unit 1310 may perform prediction on a divided block basis. In other words, the processing unit 1310 can generate the divided prediction block by performing the prediction on the divided block, and can generate the divided reconstructed block by summing the divided prediction block and the reconstructed residual block.

The divided reconstructed blocks of the plurality of divided blocks may constitute reconstructed blocks for the object block. Alternatively, the reconstructed block for the target block may include reconstructed blocks that have been segmented. The reconstructed block may contain reconstructed samples.

In one embodiment, the PU segmentation indicator may indicate whether prediction, transformation and inverse transformation are performed in units of the divided blocks. For example, the name of the PU segmentation indicator may be "Intra_PU_SplitFlag ".

The PU segmentation indicator may be signaled via a bitstream.

In one embodiment, when the value of the division indicator of the upper block is the second predetermined value, the target block is divided into a plurality of divided blocks at the stage of prediction, and prediction, conversion and inverse transformation Can be signaled by the PU segmentation indicator.

In one embodiment, when the value of the partition indicator of the upper block is a second predetermined value and the value of the partition indicator of the current block is the first predetermined value, the target block is divided into a plurality of divided blocks , And whether the prediction, transformation and inverse transformation are to be performed on the divided block can be signaled by the PU segmentation indicator.

In one embodiment, when the shape and / or shape of the target block is a shape and / or a shape to which the segmentation is applied, the target block is divided into a plurality of segmented blocks at the stage of prediction, Whether conversion and inverse transformation is to be performed can be signaled by the PU segmentation indicator.

In one embodiment, when the value of the partition indicator of the upper block is the second predetermined value, the target block may be divided into a plurality of divided blocks at the stage of prediction, and the prediction, An inverse transformation can be performed.

In one embodiment, when the value of the partitioning indicator of the upper block is the second predetermined value and the value of the partitioning indicator of the object block is the first predetermined value, the target block is divided into a plurality of square blocks Blocks, and predictions, transforms, and inverse transforms can be performed on the divided blocks.

In one embodiment, if the shape and / or shape of the target block is a shape and / or shape to which the segmentation is applied, the target block may be divided into a plurality of segmented blocks at the stage of prediction, Prediction, conversion, and inverse transformation can be performed.

If the divided blocks are units of prediction and the target block is a unit of transform and inverse transform

In step 3510, the processing unit 1210 may perform prediction on a divided block basis. That is, the processing unit 1210 may perform prediction on the partitioned block to generate a partitioned residual block for the partitioned block.

The divided residual blocks of the plurality of divided blocks may constitute a residual block of the target block.

In step 3520, the processing unit 1210 may perform conversion on a target block basis. For example, the processing unit 1210 may configure the residual block of the target block using the divided residual blocks of the plurality of divided blocks. Alternatively, the residual block of the object block may include the divided residual blocks of the plurality of divided blocks.

The processing unit 120 may perform the transform on the residual block of the target block to generate the coefficients of the target block.

The result of the transform of step 3530 may include coefficients of the object block.

In step 3560, the processing unit 1310 may perform inverse transform of the target block unit using the coefficients of the target blocks. In other words, the processing unit 1210 can generate a reconstructed residual block by performing an inverse transformation on the coefficients of the target block.

The restored residual block may constitute a plurality of restored divided residual blocks. Alternatively, the processing unit 1310 may generate a plurality of reconstructed divided residual blocks by dividing the reconstructed residual block. Alternatively, the reconstructed residual block may include a plurality of reconstructed divided residual blocks.

In step 3570, the processing unit 1310 may perform prediction on a divided block basis.

In other words, the processing unit 1210 can perform prediction on the partitioned block to generate a partitioned prediction block for the partitioned block, and by adding the partitioned prediction block and the reconstructed partitioned residual block, Can be generated.

By performing prediction on the divided blocks, different prediction modes can be applied to the plurality of divided blocks, respectively.

The plurality of restored divided blocks for the plurality of divided blocks may constitute restored blocks for the object block. Alternatively, the reconstructed block for the target block may include a plurality of reconstructed divided blocks.

In one embodiment, the TU merge PU segmentation indicator may be predicted in units of the divided blocks, and may indicate whether or not conversion and inverse transform is performed in units of the target block. For example, the name of the TU merge PU segmentation indicator may be "TU_Merge_PU_splitFlag ".

The TU merge PU segmentation indicator may be signaled through the bitstream.

In one embodiment, when the value of the segmentation indicator of the upper block is the second predetermined value, conversion and inverse transformation are performed on the target block, and whether or not prediction is performed on the divided block is performed on the TU merge PU division indicator Lt; / RTI >

In one embodiment, when the value of the partitioning indicator of the upper block is the second predetermined value and the value of the partitioning indicator of the object block is the first predetermined value, the conversion and inverse transformation are performed on the object block, Lt; RTI ID = 0.0 > TU < / RTI > merge PU segmentation indicator.

In one embodiment, if the shape and / or shape of the target block is a shape and / or shape to which the segmentation is applied, conversion and inverse transformation are performed on the target block, and whether or not prediction is performed on the segmented block is performed Can be signaled by a PU segmentation indicator.

In one embodiment, if the value of the partition indicator of the upper block is the second predetermined value, a prediction can be performed on the partitioned block, and after the prediction on the partitioned blocks, . If the value of the partition indicator of the upper block is the second predetermined value, the inverse transform can be performed on the target block, predictions on the blocks after the inverse transformation on the target block can be performed, A reconstruction sample for the target block may be generated.

In one embodiment, if the value of the partitioning indicator of the upper block is the second predetermined value and the value of the partitioning indicator of the object block is the first predetermined value, the prediction can be performed on the partitioned block, Conversion to the target block may be performed after prediction on the divided blocks. When the value of the partition indicator of the upper block is the second predetermined value and the value of the partition indicator of the target block is the first predetermined value, the inverse transformation can be performed on the target block, and the inverse transformation Predictions for the later divided blocks may be performed, and reconstruction samples for the target block may be generated.

In one embodiment, if the shape and / or shape of the target block is a shape and / or shape to which the segmentation is applied, prediction can be performed on the segmented block, and after prediction on the segmented blocks, Can be performed. In addition, if the shape and / or shape of the target block is the shape and / or shape to which the segmentation is applied, the inverse transformation can be performed on the target block, and predictions on the divided blocks after the inverse transformation on the target block are performed And a reconstruction sample for the target block may be generated.

In the above-described embodiments, although the methods are described on the basis of a flowchart as a series of steps or units, the present invention is not limited to the order of the steps, and some steps may occur in different orders or simultaneously . It will also be understood by those skilled in the art that the steps depicted in the flowchart illustrations are not exclusive and that other steps may be included or that one or more steps in the flowchart may be deleted without affecting the scope of the invention You will understand.

The embodiments of the present invention described above can be implemented in the form of program instructions that can be executed through various computer components and recorded on a computer-readable recording medium. The computer-readable recording medium may include program commands, data files, data structures, and the like, alone or in combination. The program instructions recorded on the computer-readable recording medium may be those specially designed and constructed for the present invention or may be those known and used by those skilled in the computer software arts. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks and magnetic tape, optical recording media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware device may be configured to operate as one or more software modules for performing the processing according to the present invention, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Therefore, the spirit of the present invention should not be construed as being limited to the above-described embodiments, and all of the equivalents or equivalents of the claims, as well as the following claims, I will say.

Claims (20)

Generating a plurality of divided blocks by dividing a target block;
Deriving a prediction mode for at least a portion of the plurality of divided blocks; And
Performing predictions on the plurality of divided blocks based on the derived prediction mode
/ RTI > Generating a plurality of divided blocks by dividing a target block;
Deriving a prediction mode for at least a portion of the plurality of divided blocks; And
Performing predictions on the plurality of divided blocks based on the derived prediction mode
/ RTI > 3. The method of claim 2,
Wherein whether to divide the target block is determined based on information related to the target block. 3. The method of claim 2,
Wherein whether to divide the target block and the type of the division are determined based on a block division indicator. 3. The method of claim 2,
Wherein the target block is divided based on a size of the target block. 3. The method of claim 2,
Wherein the target block is divided based on the type of the target block. 3. The method of claim 2,
A prediction mode is derived for the divided blocks specified among the plurality of divided blocks,
Wherein the specified divided block is a block of a specified one of the plurality of divided blocks. 8. The method of claim 7,
Wherein the prediction mode derived for the specified divided block is used for the remaining blocks excluding the specified divided block among the plurality of divided blocks. 8. The method of claim 7,
Wherein a prediction mode determined by a combination of a prediction mode derived for the specified divided block and another prediction mode is used for the remaining blocks excluding the specified divided block among the plurality of divided blocks. 3. The method of claim 2,
Wherein the most probable mode (MPM) list is used in deriving the prediction mode. 11. The method of claim 10,
The MPM list includes a plurality of lists,
Wherein the MPM candidate modes of the plurality of MPM lists do not overlap with each other. 11. The method of claim 10,
The MPM list is configured for a specified unit,
And the specified unit is the target block. 11. The method of claim 10,
Wherein the MPM lists for the plurality of divided blocks are configured based on one or more reference blocks of the target block. 3. The method of claim 2,
Wherein a prediction mode derived for a first one of the plurality of divided blocks is used in prediction for a second one of the plurality of divided blocks. 15. The method of claim 14,
Wherein reconstructed pixels of the first block are used as reference samples of prediction for the second block. 15. The method of claim 14,
Wherein the reference samples used for the predictions of the plurality of divided blocks are reconstructed pixels adjacent to the target block. 3. The method of claim 2,
Wherein the prediction mode is derived for the lowermost block or the rightmost block among the plurality of divided blocks. 18. The method of claim 17,
And reconstructed pixels adjacent to the upper end of the target block are used as reference pixels in the prediction for the lowermost block. 3. The method of claim 2,
Wherein the predictions of the plurality of divided blocks are performed in a predetermined order,
The predetermined order is an order from the lowermost block to the uppermost block, the order from the rightmost block to the leftmost block, the lowest block is selected first, then the next block from the uppermost block, Blocks or blocks sequentially from the rightmost block to the second block are selected in order from the leftmost block to the rightmost block. Deriving a prediction mode;
Generating a plurality of divided blocks by dividing a target block; And
Performing predictions on the plurality of divided blocks based on the derived prediction mode
/ RTI >

Images