KR20120079862A - Apparatus and method for encoding and decoding motion vector - Google Patents

Abstract

PURPOSE: A device for encoding or decoding a motion vector and a method thereof are provided to predict a prediction motion vector with high relation with a current motion vector. CONSTITUTION: A first prediction unit(210) predicts a first component of a prediction motion vector using a first motion vector candidate group. A virtual motion vector generating unit(220) and a second prediction unit(230) determine horizontal components of the prediction motion vector. A component separating machine(240) separates current motion vectors of a current block into first and second components. An entropy encoding unit(260) outputs the differential value between the current motion vector and the prediction motion vector by bit streams.

Description

Apparatus and Method for Encoding and Decoding Motion Vector

The present invention relates to a motion vector encoding and decoding apparatus and method.

Currently, a motion vector encoding and decoding method widely used in the field of image encoding and decoding uses a motion vector of a neighboring block located in space and time around a encoding target block (hereinafter, referred to as a 'current block') as a prediction value. It predicts and encodes a motion vector (hereinafter, referred to as a 'current motion vector') of the current block. That is, since the current motion vector has a significant correlation with the motion vector of the neighboring block, the predicted value of the current motion vector (hereinafter referred to as 'predictive motion vector') is calculated from the motion vector of the neighboring block by a predetermined method. After that, by encoding only the differential motion vector for the predicted motion vector without encoding the current motion vector itself, the amount of bits to be encoded is reduced to increase the coding efficiency.

In H.264 / AVC, a predicted motion vector is calculated by performing a median operation on motion vectors of neighboring blocks of a current block to be encoded.

While this technique contributes somewhat to reduce the amount of bits required to encode a motion vector, there is a limit to predicting an optimal predicted motion vector highly correlated with the motion vector of the current block. There is also a limit to improvement.

In order to solve this problem, the present invention separately predicts a first component and a second component of a predicted motion vector, wherein the first component is predicted using motion vectors of neighboring blocks adjacent to the current block, and the second component is predicted. An object of the present invention is to provide an encoding and decoding apparatus and method capable of improving encoding efficiency by predicting virtual motion vectors generated by interpolating motion vectors of neighboring blocks and motion vectors of neighboring blocks.

In order to achieve the above object, the present invention provides a motion vector encoding apparatus for encoding a motion vector (hereinafter, referred to as a 'current motion vector') of an encoding target block, the motion of at least one neighboring block adjacent to the encoding target block. A first predictor for predicting a first component of a predicted motion vector using a first motion vector candidate set generated based on the vector; A virtual motion vector generator configured to determine whether interpolation using the motion vectors of the at least one neighboring block is possible, and to generate at least one virtual motion vector by performing interpolation according to the determination result; A second component of the prediction motion vector is generated by using a second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector output by the virtual motion vector generator and a first component of the current motion vector. A second predictor for predicting; And a motion vector encoder for encoding the current motion vector using the predicted motion vector.

Here, the second predictor uses the motion vector candidate having a first component closest to the first component of the current motion vector among the motion vector candidates belonging to the second motion vector candidate set, to determine the predicted motion vector. The second component can be predicted. Further, when there are a plurality of motion vector candidates having a first component closest to the first component of the predicted motion vector, the average value of the second components of the plurality of motion vector candidates is used as the second component of the predicted motion vector. It can be predicted.

Meanwhile, the virtual motion vector generator selects two neighboring blocks among neighboring blocks adjacent to the encoding target block and performs integer-based interpolation on the motion vectors of the selected two neighboring blocks to perform the at least one virtual motion. A vector may be generated, and in selecting two neighboring blocks, adjacent blocks may be selected.

For still another purpose, the present invention provides a motion vector for reconstructing a decoded motion vector generated by decoding a coded motion vector of a decoding target block into a motion vector of the decoding target block (hereinafter, referred to as a 'current motion vector'). A decoding apparatus, comprising: predicting a first component of a predicted motion vector by using a first motion vector candidate set generated based on a motion vector of at least one neighboring block adjacent to the decoding target block, A first component reconstruction unit for reconstructing a first component of the current motion vector by using a first component and a first component of the predicted motion vector; A virtual motion vector generator configured to determine whether interpolation using the motion vectors of the at least one neighboring block is possible, and to generate at least one virtual motion vector by performing interpolation according to the determination result; And a second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector output by the virtual motion vector generator, and a first component of the current motion vector reconstructed by the first component recovery unit. A second component reconstructor configured to predict a second component of the predicted motion vector and to reconstruct a second component of the current motion vector by using the second component of the decoded motion vector and the second component of the predicted motion vector. A motion vector decoding apparatus is provided.

According to another aspect of the present invention, there is provided an apparatus for determining a predicted motion vector with respect to a motion vector of a block to be encoded or decoded (hereinafter, referred to as a 'current motion vector'), at least one adjacent to the block to be encoded or decoded. A first predictor for predicting a first component of a predicted motion vector using a first motion vector candidate set generated based on the motion vectors of neighboring blocks of the first motion vector candidate set; A virtual motion vector generator configured to determine whether interpolation using the motion vectors of the at least one neighboring block is possible, and to generate at least one virtual motion vector by performing interpolation according to the determination result; And a second component of the prediction motion vector using the second motion vector candidate set and the first component of the current motion vector, the second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector output by the virtual motion vector generator. It provides a prediction motion vector determination apparatus comprising a second prediction unit for predicting the.

According to another aspect of the present invention, in the motion vector encoding method for encoding a motion vector (hereinafter, referred to as a 'current motion vector') of an encoding target block, the motion vector of at least one neighboring block adjacent to the encoding target block is provided. A first prediction step of predicting a first component of a predicted motion vector by using the first motion vector candidate set generated based on the first motion vector candidate set; Determining whether or not interpolation is possible using the motion vectors of the at least one neighboring block, and generating at least one virtual motion vector by performing interpolation according to the determination result; A second component of the predicted motion vector using a second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector generated in the virtual motion vector generation step and a first component of the current motion vector; Predicting a second step; And a motion vector encoding step of performing encoding on the current motion vector using the predicted motion vector.

For still another purpose, the present invention provides a motion vector for reconstructing a decoded motion vector generated by decoding a coded motion vector of a decoding target block into a motion vector of the decoding target block (hereinafter, referred to as a 'current motion vector'). A decoding method comprising: predicting a first component of a predicted motion vector by using a first motion vector candidate set generated based on a motion vector of at least one neighboring block adjacent to the decoding target block, A first component reconstruction step of reconstructing a first component of the current motion vector using a first component and a first component of the predicted motion vector; Determining whether or not interpolation is possible using the motion vectors of the at least one neighboring block, and generating at least one virtual motion vector by performing interpolation according to the determination result; And a second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector generated in the virtual motion vector generation step and a first component of the current motion vector reconstructed in the first component recovery step. Second component reconstruction for predicting a second component of the predicted motion vector, and reconstructing a second component of the current motion vector using the second component of the decoded motion vector and the second component of the predicted motion vector. It provides a motion vector decoding method comprising the step.

According to the present invention, since the predicted motion vector having a high correlation with the current motion vector can be predicted, the coding efficiency of the motion vector can be improved, thereby improving the coding efficiency of the entire image.

1 is a block diagram showing a configuration of a video encoding apparatus according to an embodiment of the present invention;
2 is a block diagram showing a configuration of a motion vector encoding apparatus according to an embodiment of the present invention;
3 is an exemplary diagram illustrating neighboring blocks adjacent to a current block;
4 is an exemplary diagram for explaining a process of generating a virtual motion vector according to an embodiment of the present invention;
5 is a flowchart illustrating a motion vector encoding method according to an embodiment of the present invention;
6 is a block diagram showing a configuration of an image decoding apparatus according to an embodiment of the present invention;
7 is a block diagram showing the configuration of a motion vector decoding apparatus according to an embodiment of the present invention;
8 is a flowchart illustrating a motion vector decoding method according to an embodiment of the present invention.

1 is a block diagram illustrating a configuration of an image encoding apparatus according to an embodiment of the present invention.

An image encoding apparatus according to an embodiment of the present invention includes an intra predictor 110, an inter predictor 120, a subtractor 130, a transform and quantizer 140, an encoder 150, an inverse quantization and inverse transform unit. 160, an adder 170, a frame memory 180, and the like.

The video encoding apparatus may be a personal computer (PC), a notebook computer, a personal digital assistant (PDA), a portable multimedia player (PMP), a PlayStation Portable (PSP), It may be a mobile communication terminal, a communication device such as a communication modem for communicating with various devices or a wired / wireless communication network, a memory for storing various programs for encoding an image and data, and a calculation by executing a program And various devices including a microprocessor for controlling and the like.

An image to be encoded can be divided into blocks and input. The sizes of the blocks can be variously defined.

 The intra predictor 110 generates an intra predicted block of the current block by using a reference pixel value that can be used in an adjacent block that is spatially adjacent to the current block. In this case, an error value between the current block and the intra prediction block is calculated for each of the available intra prediction modes, and the intra prediction block is generated by applying the intra prediction mode having the minimum error value. In addition, the encoder 150 provides information about an intra prediction mode having a minimum error value.

The inter prediction unit 120 determines a search region in a previous frame that has already been encoded and reconstructed, and performs a motion estimation process in the determined search region, and has a high correlation with the current block, that is, a minimum error for the current block. Generate an intra prediction block to generate. In addition, the encoder 150 provides a motion vector (current motion vector) for the current block generated through the motion estimation process.

The subtractor 130 subtracts the input current block and the intra prediction block or the inter prediction block received from the intra prediction unit 110 or the inter prediction unit 120 to generate a residual block, and then transforms and quantizes the residual block. Transfer to the unit 140. That is, the subtractor 130 generates a residual block by subtracting the pixel value of the current block and the pixel value of the prediction block received from the intra predictor 110 or the inter predictor 120.

The transform and quantization unit 140 converts the residual block generated by the subtractor 130 into the frequency domain and quantizes it. That is, the transform and quantization unit 140 converts the residual coefficients of the residual block generated by the subtractor 130 into a frequency domain to generate a residual block having frequency coefficients, and quantizes the residual block having frequency coefficients. Here, as a transformation method, a technique of transforming an image signal in a spatial domain into a frequency domain, such as a Hadamard transform or a discrete cosine transform based integer transform, may be used. Various quantization techniques such as Dead Zone Uniform Threshold Quantization (DZUTQ) or Quantization Weighted Matrix (DZUTQ) may be used. However, the transformation and quantization scheme is not limited thereto, and more various transformation and quantization techniques may be used.

The encoder 150 generates encoded data by encoding the residual block transformed and quantized by the transform and quantization unit 140. The generated encoded data may be output as a bitstream. As the encoding technique used by the encoder 150, an entropy encoding technique may be used, but the present disclosure is not limited thereto and various other encoding techniques may be used.

In addition, the encoder 150 may include various pieces of information necessary for decoding the encoded data in the encoded data. For example, the coded data may include a first field including a coded block pattern (CBP), a delta quantization parameter, a bit string in which the quantization frequency coefficient is encoded, and information necessary for prediction (eg, In case of intra prediction, a second field including information on an intra prediction mode, motion information in case of inter prediction, etc. may be included.

In addition, the encoder 150 may determine the index information of the reference frame used for the motion estimation or the precision of the motion vector (for example, 1 / 2-pixel unit, 1 / 4-pixel unit, 1/8 unit pixel unit, etc.). You can also output However, if the encoding device and the decoding device have previously promised which values to use in advance, they may be mutually promised, for example, to use a reference frame that is most recent in time, or 1 / 4-pixel units as the precision of motion information. Such information may not be output in the case where the encoding device and the decoding device mutually promise each other.

In particular, the encoder 150 may include a motion vector encoding apparatus for encoding a motion vector. The motion vector encoding apparatus includes a predicted motion vector determined according to a predicted motion vector determination method proposed in an embodiment of the present invention. A differential motion vector is generated using the current motion vector, and the generated differential motion vector is encoded. The motion vector encoding apparatus will be described later with reference to FIGS. 2 to 4.

The inverse quantization and inverse transform unit 160 inversely quantizes and inverse transforms the residual block transformed and quantized by the transform and quantization unit 140 to restore the residual block. That is, inverse quantization and inverse transformation perform the transformation and quantization processes inversely performed by the transform and quantization unit 140 and may be implemented in various ways. For example, the transform and inverse transform or the quantization and inverse quantization of the same process that the transform and quantization unit 140 and the inverse quantization and inverse transform unit 160 share in advance may be used, or the inverse quantization and inverse transform unit 160 may be used. The residual data encoder uses information about a transform and quantization process generated and transmitted by the transform and quantization process of the transform and quantization unit 140 (for example, information on transform size, transform shape, and quantization type). Inverse quantization and inverse transformation may be performed by inversely performing the transform and quantization process of 230.

The adder 170 generates a reconstructed block by adding the residual block reconstructed by the inverse quantization and inverse transform unit 160 and the prediction block output from the intra predictor 110 or the inter predictor 120. The generated reconstruction block is stored in the frame memory 180 and used as a reference frame for encoding a target block to be encoded later.

On the other hand, although not shown in Figure 1, the image encoding apparatus according to an embodiment of the present invention may include a deblocking filter for filtering the reconstructed block in order to reduce the blocking effect caused by block-based prediction and quantization. In this case, in the case of intra prediction, a reconstructed block that is not filtered by the deblocking filter may be used, and in the case of inter prediction, the filtered reconstructed block may be used.

2 is a block diagram illustrating a configuration of a motion vector encoding apparatus according to an embodiment of the present invention, and these configurations may be implemented as independent hardware or software modules.

The motion vector encoding apparatus according to the embodiment of the present invention may include a predictive motion vector determiner 200, a component separator 240, a difference divider 252 and 254, and an entropy encoder 260.

The predicted motion vector determiner 200 determines a predicted motion vector for the current motion vector according to the method proposed by the embodiment of the present invention, and includes a first predictor 210, a virtual motion vector generator 220, and a first motion vector. 2 may include a predictor 230.

The first predictor 210 predicts a first component of the predicted motion vector by using the first motion vector candidate set generated based on the motion vectors of at least one neighboring block adjacent to the current block, and then predicts the first motion vector candidate. The set generator 212 and the first component predictor 214 may be included. In the following description, the first component is assumed to be a vertical component and the second component is a horizontal component for convenience of description. However, the present invention is not limited thereto, and the first component may be a horizontal component and the second component may be a vertical component. It is self-evident.

The first motion vector candidate set generator 212 selects first motion vector candidates using at least one neighboring block adjacent to the current block.

, 주변블록 A, B, C의 움직임벡터를 각각

,

,

라 하면, 제1 움직임벡터 후보집합 생성부(212)는 주변블록의 움직임벡터 {

,

,

}를 제1 움직임벡터 후보집합으로 선정할 수 있다. 또는 제1 예측부(210)는 예측 움직임벡터의 제1 성분, 즉, 수직성분을 예측하는 기능을 수행하므로, 주변블록의 움직임벡터의 제1 성분만을 추출하여 {

,

,

}를 제1 움직임벡터 후보로 선정할 수도 있다. 본 실시예에서는 현재블록에 대해 공간적으로 좌측, 상단, 우측상단에 위치한 주변블록들을 이용하여 제1 움직임벡터 후보집합을 선정하는 것으로 설명하고 있으나, 반드시 이에 한정되는 것은 아니며, 구현 방법이나 필요에 따라 보다 다양한 움직임 벡터들을 후보로서 선택할 수 있을 것이다. For example, referring to FIG. 3, it is assumed that the current block is D, the neighboring coded neighboring blocks adjacent to the current block are A, B, and C, and the motion vector of the current block D is calculated.

, The motion vectors of neighboring blocks A, B, and C, respectively

,

,

In this case, the first motion vector candidate set generator 212 may include a motion vector {of a neighboring block {

,

,

} May be selected as the first motion vector candidate set. Alternatively, since the first predictor 210 performs a function of predicting the first component of the predicted motion vector, that is, the vertical component, the first predictor 210 extracts only the first component of the motion vector of the neighboring block {

,

,

} May be selected as the first motion vector candidate. In the present exemplary embodiment, the first motion vector candidate set is selected by using neighboring blocks located on the left, top, and right upper sides of the current block, but the present invention is not limited thereto. More various motion vectors may be selected as candidates.

For example, a motion vector of a block located at the top left in space may also be used as a candidate, and a motion vector of a block located at the same or adjacent position as the current block in a reference frame encoded in time is peripheral to the current block. Candidate sets may be configured as blocks. Alternatively, if no candidate is available, an arbitrary prediction value (for example, (0, 0)) may be used as the only candidate. That is, the candidate set may be defined in various ways on the assumption that the definition is shared between the encoding apparatus and the decoding apparatus in advance.

The first component predictor 214 predicts the first component of the predicted motion vector by using the first motion vector candidates generated by the first motion vector candidate set generator 212. For example, as shown in Equation 1, the first component predictor 214 may predict the median value of the first components of the first motion vector candidates as the first component PMVy of the predicted motion vector. However, the present invention is not limited thereto, and the first component predictor 214 may predict the first component of the predicted motion vector in various ways by using the first motion vector candidates, for example, an average value of the first motion vector candidates. May be selected as the predicted motion vector.

The virtual motion vector generator 220 and the second predictor 230 are components for determining a second component, that is, a horizontal component, of the predicted motion vector. Among them, the virtual motion vector generator 220 is a current block. It is determined whether interpolation using neighboring blocks adjacent to is possible, and if the interpolation is possible, interpolating the neighboring blocks to generate a virtual motion vector. Here, interpolation means obtaining a value between the points based on a value given to several points using a specific function, and linear interpolation and non-linear interpolation according to the type of the specific function. ) Can be separated. Hereinafter, although it will be described as interpolating motion vectors of neighboring blocks using linear interpolation, the scope of the present invention is not limited thereto, and it should be interpreted that the use of nonlinear interpolation is included in the scope of the present invention.

For example, assuming that the motion vectors of two neighboring blocks are MV1 (x1, y1) and MV2 (x2, y2), respectively, and y2≥y1, the virtual motion vector generator 220 is a first component. It is determined whether the distance difference between y1 and y2 is 1 or less. If y1 = y2 or y2-y1 = 1, it is determined that interpolation of two neighboring blocks MV1 (x1, y1) and MV2 (x2, y2) is impossible, otherwise MV1 ( The virtual motion vector is generated by performing interpolation between x1, y1) and MV2 (x2, y2).

Inclination = (x2-x1) / (y2-y1)

y = y1 + 1

While (y! = Y2)

x = floor (Inclination * (y-y1)) + x1;

Select (x, y) as a virtual motion vector

y = y + 1

End while

In this algorithm, the variable "Inclination" means the slope between two motion vectors MV1 (x1, y1) and MV2 (x2, y2). According to this algorithm, the first component y is sequentially increased from y1 to y2, and linear interpolation is performed on all integer values between y1 and y2. However, assuming that the motion vector is determined in units of pixels, and therefore the value of the motion vector should be an integer, interpolation should be performed on an integer basis. To this end, in the present embodiment, when the x value obtained by performing the linear interpolation using the "floor" operation has a value less than or equal to the decimal point, a rounding operation is performed.

Referring to FIG. 4, a process of generating a virtual motion vector will be described in more detail, where MV1 = (x1, y1) = (2,2) and MV2 = (x2, y2) = (4, 6). At this time, since y1 and y2 have a distance of 2 or more, the virtual motion vector generator 220 performs an integer-based interpolation by performing the same operation as the algorithm described above.

First, when increasing the value of y by 1 from y1 = 2 (when y = 3), the value of x is x = floor (2.5) = 2. Therefore, VMV1 = (2, 3) is generated as a virtual motion vector.

Then increase the value of y again by 1 to find the value of x when y = 4, where x = floor (3) = 3. Therefore, VMV2 = (3, 4) is generated as a virtual motion vector.

Increasing the value of y again by 1 to find the value of x when y = 5 yields x = floor (3.5) = 3. Therefore, VMV3 = (3, 5) is generated as a virtual motion vector.

If y is increased by 1 again, y = 6, and thus y = y2, the algorithm is terminated and finally three virtual motion vectors are generated, VMV1, VMV2, and VMV3.

In the present embodiment, a rounding operation is used to perform integer-based interpolation, but the scope of the present invention is not limited thereto, and the rounding or rounding operation may be used to make the x value an integer. In addition, in the present exemplary embodiment, interpolation is performed to obtain an x value by increasing the y value by 1 based on the first component, that is, the vertical y value, but the present invention is not limited thereto. You can also interpolate by incrementing by 1 to find the y value.

In addition, in the present embodiment, for convenience of explanation, it is assumed that y2≥y1. However, if y1≥y2, an interpolation to find x while increasing by 1 based on y2 is performed or reduced by 1 based on y1. You can also do interpolation to find x.

Meanwhile, in addition to the above-described algorithm, the virtual motion vector generator 220 may perform interpolation by obtaining an average value of motion vectors of two neighboring blocks, as in the following algorithm.

y = (y1 + y2) >> 1

x = (x1 + x2) >> 1

Generate (x, y) as a virtual motion vector

In the above algorithm, ">>" means shifting a binary calculated value to the right. Shifting a binary value created by adding two values to the right by 1 is the same as calculating the average of two binary numbers. Do. More precisely, it is equivalent to taking the average of two binary numbers and then rounding them down.

As in the example of Figure 4, if MV1 = (x1, y1) = (2, 2), and MV2 = (x2, y2) = (4, 6), the virtual motion vector generated by the above algorithm is VMV = (3,4). If MV1 = (x1, y1) = (2,3) and MV2 = (x2, y2) = (5, 6), then the virtual motion vector generated by the above algorithm is VMV = (3,4) do.

,

,

}으로부터 두 개의 움직임벡터를 선별하고, 선별한 두 개의 움직임벡터를 이용하여 전술한 인터폴레이션을 수행함으로써 가상 움직임벡터를 생성한다. 즉,

와

를 이용하여 가상 움직임벡터를 생성하고,

와

를 이용하여 가상움직임벡터를 생성하며,

와

를 이용하여 가상 움직임벡터를 생성할 수 있다. 한편, 주변블록들 간의 인접성을 고려하여,

와

,

와

만을 이용하여 가상 움직임벡터를 생성할 수도 있을 것이다. 즉, 서로 인접한 주변블록들 간의 상관관계가 더 높을 수 있다는 것을 고려하여 서로 인접한 주변블록들만을 이용하여 가상 움직임벡터를 생성할 수 있다. 그러나 이에 한정되는 것은 아니며, 현재블록에 대한 주변블록, 즉, 시간적 또는 공간적으로 주변에 위치한 다양한 주변블록들 중 임의의 두 개를 선별하여 가상 움직임벡터를 생성할 수 있을 것이다.The virtual motion vector generator 220 selects motion vectors of neighboring blocks adjacent to the current block, for example, the first motion vector candidate set {

,

,

}, Two motion vectors are selected from each other, and a virtual motion vector is generated by performing the above-described interpolation using the selected two motion vectors. In other words,

Wow

Create a virtual motion vector using

Wow

To generate a virtual motion vector,

Wow

A virtual motion vector can be generated using. Meanwhile, in consideration of the proximity between neighboring blocks,

Wow

,

Wow

It is also possible to generate a virtual motion vector using only. That is, the virtual motion vector may be generated using only neighboring blocks adjacent to each other in consideration that correlation between neighboring neighboring blocks may be higher. However, the present invention is not limited thereto, and a virtual motion vector may be generated by selecting any two of the neighboring blocks, that is, the various neighboring blocks located in the temporal or spatial vicinity.

,

,

와 이 움직임벡터들을 이용하여 생성한 가상 움직임벡터들을 제2 움직임벡터 후보들로 선정한다. 가상 움직임벡터는 가상 움직임벡터 생성부(220)가 인터폴레이션이 가능하다고 판단한 경우에 생성되고, 그렇지 않은 경우에는 생성되지 않는다. 따라서 제2 움직임벡터 후보집합 생성부(232)는 가상 움직임벡터 생성부(220)로부터 생성 또는 출력되는 가상 움직임벡터가 없는 경우 주변블록의 움직임벡터만을 이용하여 제2 움직임벡터 후보집합을 생성하게 된다.The second predictor 230 may include a second motion vector candidate set generator 232 and a second component predictor 234. The second motion vector candidate set generator 232 may be adjacent to the current block. The second motion vector candidate set including the motion vectors of the neighboring blocks and the virtual motion vectors generated by the virtual motion vector generator 220 is generated. That is, the motion vectors of neighboring blocks A, B, and C adjacent to the current block D

,

,

And virtual motion vectors generated using the motion vectors are selected as second motion vector candidates. The virtual motion vector is generated when the virtual motion vector generator 220 determines that interpolation is possible. Otherwise, the virtual motion vector is not generated. Accordingly, when there is no virtual motion vector generated or output from the virtual motion vector generator 220, the second motion vector candidate set generator 232 generates a second motion vector candidate set using only motion vectors of neighboring blocks. .

The second component predictor 234 predicts the motion by using the second motion vector candidates generated by the second motion vector candidate set generator 232 and the first component of the current motion vector output by the component separator 240. Predict the second component of the vector.

For example, the second component predictor 234 may determine the second component of the motion vector candidate having the first component having the closest distance to the first component of the current motion vector among the second motion vector candidates. Can be predicted by component.

Furthermore, when there are a plurality of motion vector candidates having a first component closest to the first component of the current motion vector, the average value of the second components of the plurality of motion vectors may be used as the second component of the predicted motion vector. Alternatively, an intermediate value of the second components of the plurality of motion vectors may be used as the second component of the predicted motion vector.

The component separator 240 receives a current motion vector of the current block obtained through the motion estimation process, separates the first component into a first component and a second component, and divides the first component into a difference unit 252 and a second component predictor ( 234, the second component is output to the difference 254.

The difference unit 252 subtracts the predicted motion vector first component predicted by the first component predictor 214 and the first component of the current motion vector output from the component separator 240 and subtracts the result from the entropy encoder. 260).

The difference unit 254 subtracts the predicted motion vector second component predicted by the second component predictor 234 and the current motion vector second component output from the component separator 240 and outputs the entropy encoding 260. .

The entropy encoder 260 entropy encodes a value output from the difference units 252 and 254, that is, a difference value between a current motion vector and a predicted motion vector, and outputs the bitstream by entropy encoding.

5 is a flowchart illustrating a motion vector encoding method according to an embodiment of the present invention.

A motion vector encoding method according to an embodiment of the present invention includes a first prediction step (S510) for predicting a first component of a predicted motion vector, a virtual motion vector generation step (520), and a second component for predicting a second component of a predicted motion vector. It may include two prediction step (S530) and motion vector encoding step (S540).

The first prediction step S510 generates a first motion vector candidate set based on the motion vectors of neighboring blocks adjacent to the current block, and predicts a first component of the predicted motion vector by using the generated first motion vector candidate set. do.

The virtual motion vector generation step (S520) determines whether interpolation using motion vectors of neighboring blocks adjacent to the current block is possible, and if possible, interpolates the motion vectors of the neighboring blocks to generate a virtual motion vector.

The second prediction step S530 generates second motion vector candidates including the motion vectors of the neighboring blocks adjacent to the current block and the virtual motion vector generated in the generating a virtual motion vector step S520, and the second motion vector candidates. The second component of the predicted motion vector is predicted using the first component of the current motion vector.

In the motion vector encoding operation S540, the current motion vector is encoded by using the predicted motion vectors generated by the first prediction step S510 and the second prediction step S530. For example, entropy encoding is performed on the difference between the current motion vector and the predicted motion vector.

The first prediction step S510 includes a first predictor 210, a virtual motion vector generation step S520, a virtual motion vector generator 220, a second prediction step S530, a second predictor 230, Since the motion vector coding step S540 is the same as that performed in the subcarriers 252 and 254 and the entropy coding unit 260, the description of each step will be omitted in order to avoid redundant explanation.

The motion vector encoding method described above may be implemented by a computer program, stored in a recording medium, and implemented by a computer accessing the recording medium to execute a program. However, the present invention is not limited thereto, and the modules performing each step of the motion vector encoding method may be implemented as one hardware chip, and the motion vector encoding method may be implemented by operating the hardware chip.

6 is a block diagram illustrating a configuration of an image decoding apparatus according to an embodiment of the present invention.

An image decoding apparatus according to an embodiment of the present invention, like the image encoding apparatus described above with reference to FIG. 1, includes a personal computer (PC), a notebook computer, a personal digital assistant (PDA), and a portable multimedia device. It may be a player (PMP: Portable Multimedia Player), PlayStation Portable (PSP: PlayStation Portable), a mobile communication terminal (Mobile Communication Terminal), and the like, communication devices such as communication modems for communicating with various devices or wired and wireless communication networks, images Means a variety of devices including a memory for storing the program and a memory for storing the data, a microprocessor for the operation and control by running the program.

An image decoding apparatus according to an embodiment of the present invention includes a decoder 610, an inverse quantization and inverse transform unit 620, an intra predictor 630, an inter predictor 640, an adder 650, and a frame memory 660. ) May be included.

The decoder 610 entropy-decodes the received encoded data and extracts information necessary for block-by-block decoding. That is, the decoder 610 decodes the encoded data to extract the quantized frequency coefficient sequence, and inversely scans the quantized frequency coefficient sequence to generate a residual block having the quantized frequency coefficients. For example, if the encoding apparatus uses the zigzag scanning scheme, the decoding apparatus applies the inverse zigzag scanning scheme to inversely scan the quantized frequency coefficient sequence to generate a residual block having the quantized frequency coefficients.

In this case, the decoder 610 may extract and decode the encoded residual block from the first field included in the encoded data, extract information necessary for prediction from the second field included in the encoded data, and then extract the information from the intra predictor ( 620 or the inter predictor 630.

Meanwhile, the decoder 610 may include a motion vector decoding apparatus proposed by an embodiment of the present invention, which will be described later with reference to FIG. 7.

The inverse quantization and inverse transform unit 620 inverse quantizes the quantized residual block received from the decoder 610 and inversely transforms it to generate a residual block.

The intra prediction unit 630 generates an intra prediction block for the current block by using information (eg, information about an intra prediction mode) required for intra prediction transmitted from the decoder 610.

The inter prediction unit 640 generates an inter prediction block by using information (eg, a motion vector of the current block) required for inter prediction transmitted from the decoder 610.

The adder 650 reconstructs the current block by adding the prediction block delivered from the intra prediction unit 630 or the inter prediction unit 640 and the residual block transferred from the inverse quantization and inverse transform unit 620. The reconstructed current block is stored in the frame memory 660 and then used to predict other blocks.

On the other hand, although not shown in Figure 6, the image decoding apparatus according to an embodiment of the present invention may include a deblocking filter for filtering the reconstructed block in order to reduce the blocking effect caused by block-based prediction and quantization. In this case, in the case of intra prediction, a reconstructed block that is not filtered by the deblocking filter may be used, and in the case of inter prediction, the filtered reconstructed block may be used.

7 is a block diagram illustrating a configuration of a motion vector decoding apparatus according to an embodiment of the present invention, and these configurations may be implemented as independent hardware or software modules.

The motion vector decoding apparatus according to an embodiment of the present invention comprises an entropy decoder 710, a first component reconstructor 720, a virtual motion vector generator 730, a second component reconstructor 740, and a motion vector configuration. May include group 750.

The entropy decoder 710 entropy decodes the encoded motion vector to generate a decoded motion vector, and decompresses the first component and the second component of the decoded motion vector by the first component reconstructor 720 and the second component, respectively. Transfer to section 740.

The first component reconstructor 720 predicts the first component of the predicted motion vector by using the first motion vector candidate set generated based on the motion vectors of at least one neighboring block adjacent to the current block as the decoding target block, The first component of the current motion vector is reconstructed using the first component of the decoded motion vector and the first component of the predicted motion vector transmitted from the entropy decoder 710.

More specifically, the first component reconstructor 720 may include a first motion vector candidate set generator 722, a first component predictor 724, and an adder 726.

,

,

}를 제1 움직임벡터 후보집합으로 선정할 수 있다. 또는 주변블록의 움직임벡터의 제1 성분만을 추출하여 {

,

,

}를 제1 움직임벡터 후보로 선정할 수도 있다. 본 실시예에서는 현재블록에 대해 공간적으로 좌측, 상단, 우측상단에 위치한 주변블록들을 이용하여 제1 움직임벡터 후보집합을 선정하는 것으로 설명하고 있으나, 반드시 이에 한정되는 것은 아니며, 움직임벡터 복호화 장치와 움직임벡터 부호화 장치가 제1 움직임벡터 후보집합에 대한 생성 기준을 공유하는 한, 다양한 방식으로 제1 움직임벡터 후보집합을 선정할 수 있을 것이다.The first motion vector candidate set generator 722 selects a motion vector of at least one neighboring block adjacent to the current block by using the position information of the current block, and uses the motion vector of the neighboring block to select the first motion vector. Select a candidate set. For example, referring to FIG. 3, the first motion vector candidate set generator 722 may generate a motion vector {of a neighboring block adjacent to the current block D {

,

,

} May be selected as the first motion vector candidate set. Or extract only the first component of the motion vector of the neighboring block {

,

,

} May be selected as the first motion vector candidate. In the present exemplary embodiment, the first motion vector candidate set is selected by using neighboring blocks located on the left, top, and right upper sides of the current block, but the present invention is not limited thereto. As long as the vector encoding apparatus shares generation criteria for the first motion vector candidate set, the first motion vector candidate set may be selected in various ways.

The first component predictor 724 predicts the first component of the predicted motion vector by using the candidates belonging to the first motion vector candidate set. For example, if the first component predictor 214 of the motion vector encoding apparatus predicts the median value of the first components of the first motion vector candidates as the first component of the predicted motion vector by Equation 1, The first component predictor 724 also predicts a median value of the first components of the first motion vector candidates belonging to the first motion vector candidate set as the first component of the predicted motion vector.

The adder 726 adds the first component of the predicted motion vector transmitted from the first component predictor 724 and the first component of the decoded motion vector transmitted from the entropy decoding 710 to add the first component of the current motion vector. Restore The first component of the reconstructed current motion vector is transmitted to the second component reconstructor 740 and the motion vector composer 750.

The virtual motion vector generator 730 determines whether interpolation is possible using the motion vectors of at least one neighboring block adjacent to the current block, and if interpolation is possible, performs virtual interpolation using the motion vector of the neighboring block. Create a vector. The virtual motion vector generator 730 of the motion vector decoding apparatus has the same function as the virtual motion vector generator 220 of the motion vector encoding apparatus described with reference to FIGS. Detailed description will be omitted.

The second component reconstructor 740 generates a second motion vector candidate set including the motion vector of the neighboring block adjacent to the current block and the virtual motion vector output from the virtual motion vector generator 730, and the second motion vector. The second component of the predicted motion vector is predicted using the candidates belonging to the candidate set and the first component of the current motion vector reconstructed by the first component reconstructor 720. The second component of the current motion vector is reconstructed using the second component of the decoded motion vector and the second component of the predicted motion vector transmitted from the entropy decoder 710.

More specifically, the second component reconstructor 740 may include a second motion vector candidate set generator 742, a second component predictor 744, and an adder 746.

,

,

와 이 움직임벡터들을 이용하여 생성한 가상 움직임벡터들을 제2 움직임벡터 후보로 선정할 수 있다.The second motion vector candidate set generator 742 generates a second motion vector candidate set including motion vectors of neighboring blocks adjacent to the current block and virtual motion vectors generated by the virtual motion vector generator 730. For example, which is a motion vector of neighboring blocks A, B, and C adjacent to the current block D,

,

,

And virtual motion vectors generated using the motion vectors may be selected as second motion vector candidates.

The second component predictor 744 uses the second motion vector candidates generated by the second motion vector candidate set generator 742 and the first component of the current motion vector reconstructed by the first component reconstructor 720. A second component of the predicted motion vector is predicted. For example, the second component of the motion vector candidate having the first component closest to the first component of the current motion vector among the second motion vector candidates may be predicted as the second component of the predicted motion vector, and the current motion vector. When there are a plurality of motion vector candidates having a first component closest to the first component of, the average or median of the plurality of motion vector candidates may be the second component of the predicted motion vector.

The adder 746 adds a second component of the predicted motion vector predicted by the second component predictor 744 and a second component of the decoded motion vector transferred from the entropy decoder 710 to generate a second component of the current motion vector. Restore the ingredients.

The motion vector composer 750 configures and outputs the current motion vector by combining the first component and the second component of the current motion vector input from the adder 726 and the adder 746, respectively.

In FIG. 7, reference numeral 700 denotes a predicted motion vector determiner, wherein a first motion vector candidate set generator 722, a first component predictor 724, and a virtual motion vector included in the predicted motion vector determiner 700 are illustrated. The generator 730, the second motion vector candidate set generator 742, and the second component predictor 744 each include a first motion vector candidate set generator of the predicted motion vector determiner 200 shown in FIG. 2. 212, the first component predictor 214, the virtual motion vector generator 220, the second motion vector candidate set generator 232, and the second component predictor 234. That is, the motion vector coding apparatus and the motion vector decoding apparatus share the predicted motion vector determining unit to predict the same predicted motion vector. The motion vector encoding apparatus encodes the current motion vector using the predicted motion vector, The decoding apparatus decodes the current motion vector using the predicted motion vector.

8 is a flowchart illustrating a motion vector decoding method according to an embodiment of the present invention.

In the motion vector decoding method according to an embodiment of the present invention, the motion vector decoding step (S810) of decoding the encoded motion vector of the decoding target block, that is, the current block, predicts and uses the first component of the predicted motion vector. By reconstructing the first component of the current motion vector (S820), the virtual motion vector generation step (S830), and predicting the second component of the motion vector using the second component of the current motion vector. It may include a second component restoration step (S840) to restore.

The motion vector decoding step S810 entropy decodes the encoded motion vector to generate a decoded motion vector.

The first component reconstruction step (S820) predicts a first component of a predicted motion vector by using a first motion vector candidate set generated based on a motion vector of a neighboring block adjacent to the current block, and then calculates a first component of the predicted motion vector. The first component of the current motion vector is reconstructed by using the first component of the motion vector decoded in the component and the motion vector decoding step S810.

The virtual motion vector generation step (S830) determines whether interpolation is possible using the motion vectors of the neighboring blocks adjacent to the current block, and if interpolation is possible, generates a virtual motion vector by performing interpolation using the motion vectors of the neighboring blocks. do.

The second component reconstruction step S840 is a second motion vector candidate set including the motion vector of the neighboring block adjacent to the current block and the virtual motion vector output in the virtual motion vector generation step and the first component reconstruction step S820. The second component of the predicted motion vector is predicted using the first component of the current motion vector, and the second component of the predicted motion vector and the second component of the motion vector decoded in the motion vector decoding step S810 are present. Restore the second component of the motion vector.

The functions performed by the motion vector decoding step S810, the first component reconstruction step S820, the virtual motion vector generation step S830, and the second component reconstruction step S840 are respectively entropy decoding units 710 of the motion vector decoding apparatus. ), Corresponding to the first component reconstructor 720, the virtual motion vector generator 730, and the second component reconstructor 740, and thus, detailed descriptions thereof will be omitted to avoid redundant description.

The motion vector decoding method described above may be implemented as a computer program, stored in a recording medium, and implemented by a computer accessing the recording medium to execute a program. However, the present invention is not limited thereto, and the modules performing each step of the motion vector decoding method may be implemented as one hardware chip, and the motion vector decoding method may be implemented by operating the hardware chip.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

The embodiment of the present invention described above is applied to the field of image encoding and decoding for performing prediction encoding on a motion vector to determine a predictive motion vector having a high correlation with the current motion vector. Accordingly, encoding on the current motion vector is performed. Since the efficiency can be improved, it is a very useful invention.

Claims (31)

In a motion vector encoding / decoding apparatus for encoding and decoding a motion vector (hereinafter, referred to as a 'current motion vector') of a current block to be encoded and decoded,
The first component of the first predicted motion vector is predicted by using the first motion vector candidate set generated based on the motion vectors of at least one neighboring block adjacent to the current block, and the motion vectors of the at least one neighboring block are predicted. Determining whether the interpolation is possible, and performing interpolation according to the determination result to generate at least one virtual motion vector, and including a motion vector of the at least one neighboring block and the generated virtual motion vector. A motion vector encoding apparatus for predicting a second component of the first predicted motion vector by using a motion vector candidate set and a first component of the current motion vector, and then encoding the current motion vector using the first predicted motion vector. ; And
Decoding the current motion vector encoded by the motion vector encoding apparatus to generate a decoded motion vector, predicting a first component of a second predicted motion vector using the first predicted motion vector candidate set, and then decoding the motion vector. Reconstructing the first component of the current motion vector using the first component of the first motion vector and the first predicted motion vector, and using the second motion vector candidate set and the first component of the current motion vector. Predicting a second component of the second predicted motion vector and reconstructing a second component of the current motion vector by using the second component of the decoded motion vector and the second component of the second predicted motion vector. Decryption device
Motion vector encoding / decoding apparatus comprising a. In the motion vector encoding apparatus for encoding a motion vector (hereinafter referred to as the "current motion vector") of the target block,
A first predictor for predicting a first component of a predicted motion vector using a first motion vector candidate set generated based on a motion vector of at least one neighboring block adjacent to the encoding target block;
A virtual motion vector generator configured to determine whether interpolation using the motion vectors of the at least one neighboring block is possible, and to generate at least one virtual motion vector by performing interpolation according to the determination result;
A second component of the prediction motion vector is generated by using a second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector output by the virtual motion vector generator and a first component of the current motion vector. A second predictor for predicting; And
A motion vector encoder which encodes the current motion vector using the predicted motion vector.
And a motion vector coding unit for coding the motion vector. The method of claim 1,
The second predictor uses a motion vector candidate having a first component closest to a first component of the current motion vector among the motion vector candidates belonging to the second motion vector candidate set, to generate a second predictive motion vector. A motion vector encoding apparatus characterized by predicting a component. The method of claim 3, wherein
The second predictor, when there are a plurality of motion vector candidates having a first component closest to the first component of the predicted motion vector, calculates an average value of the second components of the plurality of motion vector candidates. A motion vector encoding device, characterized in that the second component. The method of claim 1,
The virtual motion vector generator selects two neighboring blocks among neighboring blocks adjacent to the encoding target block and performs integer-based interpolation on the motion vectors of the selected two neighboring blocks to obtain the at least one virtual motion vector. And a motion vector encoding apparatus. The method of claim 5, wherein
The motion vector encoding apparatus of claim 2, wherein the two neighboring blocks are adjacent to each other. The method of claim 5, wherein
And the virtual motion vector generator performs the integer based interpolation on all integer values existing between the first components of each of the motion vectors of the two neighboring blocks. The method of claim 5, wherein
And the virtual motion vector generator performs the integer based interpolation on all integer values existing between the second components of each of the motion vectors of the at least two neighboring blocks. The method of claim 5, wherein
The virtual motion vector generating unit performs the integer based interpolation by calculating an average value of the motion vectors of the two neighboring blocks. The method of claim 1,
The virtual motion vector generator selects two neighboring blocks adjacent to the encoding target block, and when the difference between the first component or the second component of the selected motion vector of the two neighboring blocks is less than or equal to 1, the selected two And a motion vector encoding apparatus for determining that interpolation is impossible with respect to motion vectors of a neighboring block. The method of claim 1,
And the at least one neighboring block includes neighboring blocks located at the same or adjacent positions as the encoding target block in a reference frame that is already encoded in time. A motion vector decoding apparatus for reconstructing a decoded motion vector generated by decoding a coded motion vector of a decoding target block into a motion vector of a decoding target block (hereinafter, referred to as a "current motion vector"),
The first component of the predicted motion vector is predicted by using the first motion vector candidate set generated based on the motion vectors of at least one neighboring block adjacent to the decoding target block, and the first component and the first component of the decoded motion vector are predicted. A first component reconstruction unit for reconstructing a first component of the current motion vector by using a first component of a predicted motion vector;
A virtual motion vector generator configured to determine whether interpolation using the motion vectors of the at least one neighboring block is possible, and to generate at least one virtual motion vector by performing interpolation according to the determination result; And
The second motion vector candidate set including the motion vector of the at least one neighboring block and the virtual motion vector output by the virtual motion vector generator and the first component of the current motion vector reconstructed by the first component reconstructor A second component reconstructor for predicting a second component of a predicted motion vector and reconstructing a second component of the current motion vector by using the second component of the decoded motion vector and the second component of the predicted motion vector
Motion vector decoding apparatus comprising a. The method of claim 12,
The second component reconstructor uses the motion vector candidate having a first component closest to the first component of the current motion vector among the motion vector candidates belonging to the second motion vector candidate set, to obtain the second component of the predicted motion vector. A motion vector decoding apparatus characterized by predicting a component. The method of claim 13,
The second component reconstructor, when there are a plurality of motion vector candidates having a first component closest to the first component of the predicted motion vector, calculates an average value of the second components of the plurality of motion vector candidates. And a second component of the motion vector decoding apparatus. The method of claim 12,
The virtual motion vector generator selects two neighboring blocks among neighboring blocks adjacent to the decoding target block and performs integer-based interpolation on the motion vectors of the selected two neighboring blocks to determine the at least one virtual motion vector. Motion vector decoding device, characterized in that for generating. The method of claim 12,
And the two neighboring blocks are adjacent to each other. The method of claim 15,
And the virtual motion vector generating unit performs the integer based interpolation on all integer values existing between the first component of each of the motion vectors of the two neighboring blocks. The method of claim 15,
And the virtual motion vector generating unit performs the integer based interpolation on all integer values existing between the second components of each of the motion vectors of the two neighboring blocks. The method of claim 15,
The virtual motion vector generating unit performs the integer based interpolation by calculating an average value of the motion vectors of the two neighboring blocks. An apparatus for determining a predicted motion vector with respect to a motion vector (hereinafter, referred to as a 'current motion vector') of a block to be encoded or decoded,
A first predictor for predicting a first component of a predicted motion vector using a first motion vector candidate set generated based on a motion vector of at least one neighboring block adjacent to the encoding or decoding target block;
A virtual motion vector generator configured to determine whether interpolation using the motion vectors of the at least one neighboring block is possible, and to generate at least one virtual motion vector by performing interpolation according to the determination result; And
A second component of the prediction motion vector is generated by using a second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector output by the virtual motion vector generator and a first component of the current motion vector. Second prediction part to predict
Predictive motion vector determination apparatus comprising a. In a motion vector encoding / decoding method for encoding and decoding a motion vector (hereinafter, referred to as a 'current motion vector') of a current block to be encoded and decoded,
The first component of the first predicted motion vector is predicted by using the first motion vector candidate set generated based on the motion vectors of at least one neighboring block adjacent to the current block, and the motion vectors of the at least one neighboring block are predicted. Determining whether the interpolation is possible, and performing interpolation according to the determination result to generate at least one virtual motion vector, and including a motion vector of the at least one neighboring block and the generated virtual motion vector. A motion vector encoding step of predicting a second component of the first predicted motion vector using a motion vector candidate set and a first component of the current motion vector, and then encoding the current motion vector using the first predicted motion vector. ; And
Decoding the current motion vector encoded by the motion vector encoding apparatus to generate a decoded motion vector, predicting a first component of a second predicted motion vector using the first predicted motion vector candidate set, and then decoding the motion vector. Reconstructing the first component of the current motion vector using the first component of the first motion vector and the first predicted motion vector, and using the second motion vector candidate set and the first component of the current motion vector. Predicting a second component of the second predicted motion vector and reconstructing a second component of the current motion vector by using the second component of the decoded motion vector and the second component of the second predicted motion vector. Decryption step
Motion vector encoding / decoding method comprising a. In a motion vector encoding method of encoding a motion vector (hereinafter, referred to as a "current motion vector") of an encoding target block,
A first prediction step of predicting a first component of a predicted motion vector using a first motion vector candidate set generated based on a motion vector of at least one neighboring block adjacent to the encoding target block;
Determining whether or not interpolation is possible using the motion vectors of the at least one neighboring block, and generating at least one virtual motion vector by performing interpolation according to the determination result;
A second component of the predicted motion vector using a second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector generated in the virtual motion vector generation step and a first component of the current motion vector; Predicting a second step; And
A motion vector encoding step of performing encoding on the current motion vector using the predicted motion vector.
Motion vector encoding method comprising a. The method of claim 22,
The second prediction step includes the first prediction of the predicted motion vector using motion vector candidates having the first component having the closest distance to the first component of the current motion vector among the motion vector candidates belonging to the second motion vector candidate set. A motion vector encoding method characterized by predicting two components. 24. The method of claim 23,
In the second prediction step, when there are a plurality of motion vector candidates having a first component closest to the first component of the predicted motion vector, the predicted motion is obtained by averaging the average value of the second components of the plurality of motion vector candidates. A motion vector encoding method comprising the second component of a vector. The method of claim 22,
The generating of the virtual motion vector may include selecting at least two neighboring blocks among neighboring blocks adjacent to the encoding target block and performing integer-based interpolation on the motion vectors of the selected two neighboring blocks to perform the at least one virtual motion vector. Motion vector encoding method, characterized in that for generating. In a motion vector decoding method for reconstructing a decoded motion vector generated by decoding a coded motion vector of a decoding target block to a motion vector (hereinafter, referred to as a "current motion vector") of the decoding target block,
The first component of the predicted motion vector is predicted by using the first motion vector candidate set generated based on the motion vectors of at least one neighboring block adjacent to the decoding target block, and the first component and the first component of the decoded motion vector are predicted. A first component reconstruction step of reconstructing a first component of the current motion vector using a first component of a predicted motion vector;
Determining whether or not interpolation is possible using the motion vectors of the at least one neighboring block, and generating at least one virtual motion vector by performing interpolation according to the determination result; And
Using a second motion vector candidate set including a motion vector of the at least one neighboring block and a virtual motion vector generated in the virtual motion vector generation step and a first component of the current motion vector reconstructed in the first component reconstruction step Predicting a second component of the predicted motion vector, and restoring a second component of the current motion vector by using the second component of the decoded motion vector and the second component of the predicted motion vector.
Motion vector decoding method comprising a. The method of claim 26,
The second component reconstructor uses the motion vector candidate having a first component closest to the first component of the current motion vector among the motion vector candidates belonging to the second motion vector candidate set, to obtain the second component of the predicted motion vector. A motion vector decoding method comprising predicting a component. The method of claim 27,
The second component reconstructor, when there are a plurality of motion vector candidates having a first component closest to the first component of the predicted motion vector, calculates an average value of the second components of the plurality of motion vector candidates. And a second component of the motion vector decoding method. The method of claim 26,
The virtual motion vector generator selects two neighboring blocks among neighboring blocks adjacent to the decoding target block and performs integer-based interpolation on the motion vectors of the selected two neighboring blocks to determine the at least one virtual motion vector. Motion vector decoding method, characterized in that for generating. A computer-readable recording medium in which a motion vector encoding method according to any one of claims 22 to 25 is recorded by a program. A computer-readable recording medium having a motion vector decoding method according to any one of claims 26 to 29.

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