KR20080060188A - A method and apparatus for decoding a video signal - Google Patents

Abstract

A video signal decoding method and apparatus are provided to reduce the amount of error value transmissions by estimating coding information of a current block by using coding information of a picture having a high correlation with the current block. A motion skip discriminating unit(750) discriminates whether to induce motion information of a current block. When the motion information of the current block s induced, a motion information inducing unit(730). When the motion information of the current block is induced, the motion information inducing unit induces motion information the current block by using motion information of a neighbor block of the current block. A motion compensating unit(740) performs motion compensation by using the motion information of the induced current block. When the motion information of the neighbor block is used, it is checked whether the neighbor block refers to a picture of a different time point.

Description

A method and apparatus for decoding a video signal

The present invention relates to the coding of video signals.

Compression coding refers to a series of signal processing techniques that transmit digitized information through a communication line or store the data in a form suitable for a storage medium. The object of compression encoding includes objects such as voice, video, text, and the like. In particular, a technique of performing compression encoding on an image is called video image compression. The general feature of the video image is that it has spatial redundancy and temporal redundancy.

An object of the present invention is to improve the coding efficiency of a video signal.

Another object of the present invention is to provide a method and apparatus for efficiently processing a multiview video signal.

It is still another object of the present invention to provide a method for predicting motion information of a video signal, thereby efficiently processing the video signal.

It is still another object of the present invention to provide a method for deriving a disparity vector, thereby efficiently processing a video signal.

Another object of the present invention is to efficiently process a video signal by providing a method for finding a block corresponding to the current block.

According to an embodiment of the present invention, determining whether to derive motion information of a current block, and when deriving motion information of the current block, deriving motion information of the current block by using motion information of a block neighboring the current block. And performing motion compensation using the derived motion information of the current block, and when using the motion information of the neighboring block, checking whether the neighboring block refers to a picture at another point in time. A video signal decoding method is provided.

In addition, when the neighboring blocks all refer to pictures in different time zones at the same time, the present invention is characterized by predicting the view direction motion vector of the current block using the motion vector of the corresponding block in the interview picture group. .

The present invention may further include setting a motion vector of the neighboring block using a motion vector of a partition block adjacent to the current block when the neighboring block is divided into partitions, wherein the motion information of the current block is included. Is derived from the set motion vector of the neighboring block.

In addition, the present invention, a motion skip determination unit for determining whether to induce the motion information of the current block, when the motion information of the current block is derived, by using the motion information of the block neighboring the current block A motion information derivation unit for deriving motion information of the block and a motion compensation unit for performing motion compensation using the derived motion information of the current block, wherein when using the motion information of the neighboring block, the neighboring block is located at different time points Provided is a video signal decoding apparatus characterized by checking whether a picture is referred to.

According to the present invention, signal processing efficiency can be improved by predicting motion information using temporal and spatial correlation of an image sequence. By predicting the coding information of the current block by using the coding information of the picture having a high correlation with the current block, more accurate prediction is possible, and the error value transmission amount is reduced accordingly, thereby enabling efficient coding. And even if the motion information of the current block is not transmitted, since the motion information very similar to the motion information of the current block can be calculated, the reconstruction rate is improved.

In addition, by predicting the coding information of the current block by using the coding information of the blocks neighboring the current block, it is possible to predict more accurately, thereby reducing the amount of transmission of the error value, thereby performing efficient coding.

The compression coding technique of video signal data considers spatial redundancy, temporal redundancy, scalable redundancy, and redundancy existing between views. In this compression encoding process, compression coding may be performed in consideration of mutual redundancy existing between views. The compression coding technique considering the inter-view redundancy is only an embodiment of the present invention, and the technical idea of the present invention may be applied to temporal redundancy, scalable redundancy, and the like. In addition, the term coding in this specification may include both the concepts of encoding and decoding, and may be flexibly interpreted according to the technical spirit and technical scope of the present invention.

1 is a schematic block diagram of a video signal decoding apparatus to which the present invention is applied.

The decoding apparatus includes a parsing unit 100, an entropy decoding unit 200, an inverse quantization / inverse transform unit 300, an intra prediction unit 400, a deblocking filter unit 500, a decoded picture buffer unit 600, Inter prediction unit 700 and the like. The inter prediction unit 700 may include a motion skip determination unit 710, a corresponding block search unit 720, a motion information derivation unit 730, a motion compensator 740, and a motion information acquisition unit 750. have.

 The parser 100 performs parsing on a network abstraction layer (NAL) basis in order to decode the received video image. In general, one or more sequence parameter sets and picture parameter sets are transmitted to the decoder before the slice header and slice data are decoded. In this case, various attribute information may be included in the NAL header area or the extension area of the NAL header. Multiview Video Coding (MVC) is an additional technology to the existing AVC technology, so it may be more efficient to add various attribute information only in the case of MVC bitstream rather than unconditionally adding. For example, flag information for identifying whether an MVC bitstream is included in the NAL header region or an extension region of the NAL header may be added. Attribute information about a multiview image may be added only when the input bitstream is a multiview image coded bitstream according to the flag information. For example, the attribute information may include view identification information, inter-view picture group identification information, and the like.

First, view identification information refers to information for distinguishing a picture at a current view from a picture at a different view. When a video image signal is coded, a picture order count (POC) and frame_num are used to identify each picture. In the case of a multiview video image, since inter-view prediction is performed, identification information for distinguishing a picture at a current view from a picture at a different view is required. Therefore, it is necessary to define viewpoint identification information for identifying the viewpoint of the picture. The view identification information may be obtained from a header area of a video signal. For example, the header area may be an NAL header, an extended area of the NAL header, or a slice header. The view identification information may be used to obtain information of a picture that is different from the current picture, and the video signal may be decoded using the information of the picture at the other view.

Inter-view picture group identification information refers to information for identifying whether a coded picture of a current NAL unit is an interview picture group. The inter-view picture group means an encoded picture in which all slices refer only to slices in frames of the same time zone. For example, an encoded picture refers to only a slice at another viewpoint and no slice at the current viewpoint. In the decoding process of a multiview image, random access between views may be possible. As such, when the interview reference information is acquired based on the interview picture group identification information, random access between viewpoints can be performed more efficiently. This is because the inter-view reference relationship between the pictures in the interview picture group may be different from the inter-view reference relationship in the non-interview picture group. In this case, if the view identification information is used, more efficient random access may be possible.

The parsed bitstream is entropy decoded through the entropy decoding unit 200, and coefficients, motion vectors, and the like of each macroblock are extracted. The inverse quantization / inverse transform unit 300 multiplies the received quantized value by a constant constant to obtain a transformed coefficient value, and inversely transforms the coefficient value to restore the pixel value. Using the reconstructed pixel value, the intra prediction unit 400 performs intra prediction from the decoded samples in the current picture. Meanwhile, the deblocking filter unit 500 is applied to each coded macroblock in order to reduce block distortion. The filter smoothes the edges of the block to improve the quality of the decoded frame. The choice of filtering process depends on the boundary strength and the gradient of the image samples around the boundary. The filtered pictures are output or stored in the decoded picture buffer unit 600 for use as a reference picture.

The decoded picture buffer unit 600 stores or opens previously coded pictures in order to perform inter prediction. In this case, in order to store or open the decoded picture buffer unit 600, frame_num and POC (Picture Order Count) of each picture are used. Therefore, some of the previously coded pictures in MVC have pictures that are different from the current picture. Therefore, in order to utilize these pictures as reference pictures, not only the frame_num and the POC but also the view information for identifying the view point of the picture are included. It is available. In addition, information identifying a picture in a view direction having a concept similar to the frame_num may also be used.

The inter prediction unit 700 performs inter prediction using a reference picture stored in the decoded picture buffer unit 600. Inter-coded macroblocks can be divided into macroblock partitions, where each macroblock partition can be predicted from one or two reference pictures. The inter prediction unit 700 compensates for the movement of the current block by using the information transmitted from the entropy decoding unit 200. A motion vector of blocks neighboring the current block is extracted from the video signal, and a motion vector prediction value of the current block is obtained. The motion of the current block is compensated by using the obtained motion vector prediction value and the difference vector extracted from the video signal. This will be described in detail with reference to FIG. 2. In addition, such motion compensation may be performed using one reference picture or may be performed using a plurality of pictures. In multi-view video coding, when a current picture refers to pictures at different views, motion compensation is performed using information on a reference picture list for inter-view prediction stored in the decoded picture buffer unit 600. Can be done. In addition, motion compensation may be performed using viewpoint identification information for identifying the viewpoint of the picture.

In addition, the direct prediction mode is a coding mode for predicting motion information of a current block from motion information of a coded block. This method improves compression efficiency because the number of bits necessary for encoding motion information is saved. For example, in the temporal direct mode, the motion information of the current block is predicted using the motion information correlation in the time direction. The direct temporal mode is effective when the speed of the movement is constant in an image including different movements. In the spatial direct mode, the motion information of the current block is predicted by using the motion information correlation in the spatial direction. The spatial direct mode is effective when the speed of the motion changes in an image including the same motion.

Through the above process, the inter predicted pictures and the intra predicted pictures are selected according to the prediction mode to reconstruct the current picture. Hereinafter, various embodiments for providing an efficient decoding method of a video signal will be described.

2 is a block diagram illustrating a method of performing motion compensation according to whether to skip motion according to an embodiment to which the present invention is applied.

The unit used in the present invention may include all meanings of a block, a sub block, a macro block, a slice, a picture, a frame, a picture group, a sequence, and the like in application to a video signal. Therefore, the meaning of the unit should be interpreted as a corresponding meaning according to each application. In addition, when applied to not only a video signal but also other signals, it may be interpreted as another meaning suitable for the signal.

First, the inter predictor 700 may include a motion skip determiner 710, a corresponding unit searcher 720, a motion information derivator 730, a motion compensator 740, and a motion information acquirer 750. have. The motion skip determination unit 710 determines whether to derive the motion information of the current unit. For example, a motion skip flag can be used. When motion_skip_flag = 1, motion skip is performed, that is, motion information of the current unit is derived. On the other hand, when motion_skip_flag = 0, motion information transmitted without performing motion skip is obtained. Here, the motion information may include a motion vector, a reference index, a block type, and the like. When the motion skip is performed by the motion skip determination unit 710, the corresponding unit search unit 720 searches for the corresponding unit. The motion information deriving unit 730 may derive the motion information of the current unit by using the motion information of the corresponding unit. The motion compensation unit 740 performs motion compensation by using the derived motion information. Meanwhile, when the motion skip is not performed by the motion skip determination unit 710, the motion information acquisition unit 750 acquires the transmitted motion information. The motion compensation unit 740 performs motion compensation using the obtained motion information.

Hereinafter, specific embodiments for deriving motion information when performing a motion skip will be described.

3 is an embodiment to which the present invention is applied and is shown to explain a method of predicting motion information of a current unit.

In a multiview video sequence, each unit may be in a first domain and a second domain region. For example, the first domain may be a time domain and the second domain may be a viewpoint domain. In this case, each of the units may exist on an axis in a time direction and a view direction. Thus, some units may obtain prediction information only in the time direction, and some units may obtain prediction information only in the view direction. In addition, some units may obtain prediction information in both time and view direction. In this case, when the coding information is predicted in the time direction, when the reference units exist in different time zones at the same time point, each unit has a time direction motion vector. When the reference units exist at different time points in the same time zone, each unit has a view direction motion vector. This is sometimes called a disparity vector. Hereinafter, the motion vector may include both the concept of the time direction motion vector and the view direction motion vector. In addition, in the present invention, the coding information may include information about a motion vector, a reference index, a block type, a prediction direction, and the like.

In another embodiment to which the present invention is applied, the coding information for the second domain of the current unit may be predicted using the coding information for the second domain of the first domain unit. For example, the skip mode may mean using information of another unit coded before the current unit and using the information as the information of the current unit. In applying the skip mode, information existing in different domains may be used. Hereinafter, specific embodiments thereof will be described.

First, it can be assumed that the relative motion relationship of objects (or backgrounds) in two different viewpoint images at time Tb is maintained almost similarly even at a sufficiently close time Tc. At this time, the view direction coding information at time Tb and the view direction coding information at time Tc have a high correlation. High coding efficiency can be obtained by using the motion information of the corresponding block in different time zones at the same time. Motion skip information indicating whether such a scheme is used may be used. When the motion skip mode is applied according to the motion skip information, motion information such as a block type, a motion vector, and a reference index may be predicted from a corresponding block of the current block. Therefore, the amount of bits required for coding such motion information can be reduced. For example, when motion_skip_flag is 0, the motion skip mode is not applied, and when 1, motion skip mode is applied to the current block. The motion skip information may be located in a macroblock layer. For example, the motion skip information may be located in an extended region of the macroblock layer, so that the decoder may preferentially indicate whether motion information is obtained from the bitstream.

In addition, similarly to the above example, the same method may be used by changing the first domain and the second domain, which are algorithm application axes. That is, the object (or background) in the Vb point in time at the same time Tb and the object (or background) in the neighboring Va point in time are likely to have similar motion information. In this case, if the motion information of the corresponding block at another point in time is used as it is, high coding efficiency can be obtained. Motion skip information indicating whether such a scheme is used may be used.

In addition, in multi-view video coding, a reference picture may exist not only in the time axis but also in the view axis. Because of this characteristic, if the reference picture number of the current macroblock is different from the reference picture number of the neighboring block, the motion vectors are likely to have no correlation. In this case, the accuracy of the motion vector prediction is very poor. Therefore, as an embodiment to which the present invention is applied, a new motion vector prediction method using correlation between viewpoints is proposed.

For example, the motion vector generated between viewpoints may be dependent on the depth of each object. If the depth of the image does not change very spatially and the movement of the image itself is not very severe according to the change of time axis, the depth itself at each macroblock position will not change significantly. Here, the depth may refer to information that may indicate a difference in variation between viewpoints. In addition, since the effects of global motion vectors exist between cameras, if the global motion vector is sufficiently large compared to the depth change even if the depth is slightly changed, it is better to use the motion direction motion vector of the neighboring block without correlation. It may be more efficient to use the global motion vector.

Here, the global motion vector may mean a motion vector that can be commonly applied to a predetermined region. For example, if the motion vector corresponds to a partial region (eg, macroblock, block, pixel, etc.), the global motion vector or global disparity vector corresponds to the entire region including the partial region. to be. For example, the entire region may correspond to one slice, may correspond to one picture, or may correspond to the entire sequence. Alternatively, the image may correspond to one or more objects, a background, or a predetermined area in the picture. The global motion vector may be a value of a pixel unit or a quarter pixel unit, or may be a value of 4x4 unit, 8x8 unit, or macroblock unit.

As an embodiment to which the present invention is applied, in using the global motion vector, it is possible to determine whether to use a local disparity vector or a global motion vector. For example, a motion vector mode flag may be used. According to the disparity_mode_flag value, a local motion vector may be used or a global motion vector may be used. The motion vector mode flag may be defined at a sequence parameter set, a picture parameter set, or a slice level. When the flag information indicates that the local motion vector is to be used, the motion vector in the view direction may be derived for each macroblock. Alternatively, when the flag information indicates that the global motion vector is to be used, the global motion vector may be extracted in the bitstream.

In the multi-view video coding structure, random access can be realized by placing pictures that are predicted only in the view direction at regular time intervals. As described above, when two pictures predicting motion information only in the view direction are decoded, a new motion vector prediction method may be applied to pictures in between. For example, a view direction motion vector can be obtained from a picture predicted only in the view direction. When the illumination difference is very severe when predicting only in the view direction, many cases are coded as intra prediction. At this time, the motion vector may be set to zero. However, when the illumination difference is large and coded a lot by intra prediction, many macroblocks in which information about a motion vector in the view direction are unknown are generated. To compensate for this, in the case of intra prediction, a virtual inter-view motion vector may be calculated using a motion vector of a neighboring block. The virtual inter-view motion vector may be set as a motion vector of a block coded by the intra prediction. After inter-view motion information is obtained from the two decoded pictures, hierarchical B pictures existing therebetween may be coded. In this case, the two decoded pictures may be an interview picture group.

In another embodiment to which the present invention is applied, motion information of the current unit may be predicted using information of units neighboring the current unit.

For example, suppose that two neighboring units A and B of units neighboring the current unit M① have a time direction motion vector and one unit C has a motion vector in the view direction. In this case, in order to predict the time direction motion vector of the current unit M①, the time direction motion vectors of the neighboring units A and B may be used. In addition, the time direction motion vector of the neighboring unit C may be predicted using the view direction motion vector of the neighboring unit C. The time direction motion vector of the current unit M① may be predicted using all three time direction motion vectors including the predicted time direction motion vector of the neighboring unit C. In this way, the same applies to the second domain as the motion vector of the first domain is applied.

For example, in order to predict the view motion vector of the current unit M①, the view motion vector of the neighboring unit C may be directly used. In addition, each view direction motion vector may be predicted using the time direction motion vectors of neighboring units A and B. FIG. The three view direction motion vectors may be used to more accurately predict the view direction motion vector of the current unit M①.

In addition, the above method is applied to all combinations in which neighboring units of the current unit M① have a time direction motion vector and a view direction motion vector to apply the time direction motion vector and the view direction motion vector of the current unit M①. It can be predicted.

As a specific example, when only one neighboring unit of the neighboring units of the current unit M① refers to a unit at a different viewpoint, the view direction motion vector of the current unit M① may be predicted from the motion vector of the neighboring unit. have. And, when two or more neighboring units of the neighboring units of the current unit M① refer to a unit at a different point in time, the view direction motion vector of the current unit M① is determined from the median of the motion vectors of the neighboring units. It can be predicted. However, a motion vector of a neighboring unit that refers to a unit in another time zone at the same time point among the neighboring units may be used after setting to zero.

In addition, when the neighboring units all refer to units in different time zones at the same time, the motion vector of the corresponding unit of the neighboring interview reference picture may be used to predict the view direction motion vector of the current unit. For example, when the current unit M① refers to the plurality of interview reference pictures ② and ③, the motion vector mv②_f of the corresponding unit M② of the interview reference picture closest to each other in the time direction at the same time point is determined. It can be predicted by the view direction motion vector mv①_f of the current unit M①. In this case, the position of the corresponding unit M② of the interview reference picture may be determined by the predicted time direction motion vector mv①'_f of the current unit M①. In addition, the corresponding unit of the interview reference picture may be a unit in the same position as the current unit. Alternatively, the corresponding unit of the interview reference picture may be a unit existing at a position indicated by the temporal motion vector of the neighboring unit.

In addition, in the above embodiments, when bidirectional prediction is performed according to the block type of the current unit, it may be applicable to both forward and backward directions.

Hereinafter, specific methods of inducing a view direction motion vector from units neighboring the current unit will be described.

FIG. 4 is an embodiment to which the present invention is applied and shows a method of deriving a view direction motion vector from units neighboring a current unit.

The encoder predicts motion information of the current unit by using motion information of a unit neighboring the current unit and transmits a difference value between the actual motion vector and the predicted motion vector. Similarly, the decoder determines whether the reference number of the unit referred to by the current unit and the reference number of the unit referred to by the neighboring unit are the same and obtains a motion vector prediction value accordingly. For example, when there is only one unit having the same reference number as the current unit among the neighboring units, the motion vector of the neighboring unit is used as it is. Otherwise, the median value of the motion vectors of the neighboring units is used. ) Can be used.

As an embodiment of the present invention, when using the motion vectors of the units neighboring the current unit, specific embodiments of determining the view direction motion vector of the neighboring unit when the neighboring unit is composed of partition units .

For example, when the neighboring unit is composed of partition units, when determining the view direction motion vector of the neighboring unit, when the motion vector of the partition unit adjacent to the current unit is used, more accurate prediction can be performed. Referring to FIG. 4, FIG. 4 (a) shows a current unit and neighboring units. 4 (b) shows a case where the neighboring unit A is composed of partition units, and FIG. 4 (c) shows a case where the neighboring unit B is composed of partition units.

In detail, for example, suppose that the neighboring unit A of 16 × 16 is used, and the neighboring unit A is composed of 4 × 4 partition units. At this time, the motion vector dv0 or dv1 of the partition unit adjacent to the current unit M may be used to define the view direction motion vector of the neighboring unit A. FIG. For example, assume that a partition unit having a motion vector in the view direction among the partition units adjacent to the current unit M is a colored unit. When the partition is composed of 4 × 4 units, it may be determined whether the neighboring unit refers to a unit located adjacent to the current unit. Therefore, when the motion vector dv0 of the 4X4 unit in the upper right refers to the unit at the neighboring viewpoint, the view direction motion vector dvA of the neighboring unit A is the motion vector dv0 of the block adjacent to the current unit. May be induced. If the motion vector on the upper right side does not refer to the unit at the neighboring viewpoint, it may be determined whether the motion vector dv1 of the 4 × 4 unit at the lower right refers to the unit at the neighboring viewpoint. When the motion vector dv1 of the 4X4 unit at the lower right refers to a unit at the neighboring viewpoint, the view direction motion vector dvA of the neighboring unit A is the motion vector dv1 of the block adjacent to the current unit. Can be induced. Alternatively, when the 4x4 blocks adjacent to the current block do not all refer to a unit at a neighboring viewpoint, the view direction motion vector dvA of the neighboring unit A may be set to zero.

Similarly, when the neighboring unit B is used, the view motion vector of the neighboring unit B may be defined using the motion vector of the block adjacent to the current unit M. FIG. As in the case of using the neighboring unit A, it may be determined whether the partition unit adjacent to the current unit M refers to a unit located in the neighboring viewpoint first.

In addition, when using the neighboring unit (C), a similar method to the derivation process of the neighboring unit (B) can be applied. However, when the neighboring unit C is unavailable, for example, a unit located at the right end of the picture, the motion vector dvD of the unit D located at the upper left of the current unit M is used. Can be. Alternatively, when both dv0 and dv1 of the unit C do not refer to a unit at a neighboring viewpoint, the view direction motion vector dvD of the neighboring unit D may be used. Similarly, it can be applied similarly to the method applied in the neighboring unit (B).

The motion vector of neighboring units defined as described above may be used to derive the view direction motion vector of the current unit. In this case, the view direction motion vector of the current unit may be derived from the median of the motion vectors of the neighboring units.

FIG. 5 is a diagram for describing a method of predicting coding information of a current block using inter-view correlation as another embodiment to which the present invention is applied.

In the method of predicting a motion vector of a current block, the corresponding block existing at a different point in time from the current block may be found and the coding information of the current block may be predicted using the coding information of the corresponding block. First, a method of finding a corresponding block existing at a different point in time from the current block will be described.

For example, the corresponding block may be a block indicated by the view motion vector of the current block. Herein, the motion vector in the view direction may mean a vector representing a difference between views, or may mean a global motion vector. Here, the meaning of the global motion vector has been described with reference to FIG. 3. In addition, the global motion vector may indicate a corresponding macroblock position of neighboring view on the same temporal instant at the same time as the current block. Referring to FIG. 5, pictures A and B exist in Ta time, pictures C and D in Tcurr time, and pictures E and F in Tb time. In this case, the pictures A, B, E, and F in Ta and Tb may be interview picture groups, and the pictures C and D in Tcurr time may be non-interview picture groups. Pictures A, C, and E exist on the same viewpoint Vn, and pictures B, D, and F also exist on the same viewpoint Vm. Picture C is a picture to be currently decoded, and a corresponding macroblock (corresponding MB) of picture D is a block indicated by a global motion vector (GDVcurr) in the view direction of the current block (current MB). The global motion vector may be obtained in a macroblock unit between a current picture and a picture at a neighbor view. In this case, the information on the neighbor viewpoint may be known by information indicating a reference relation between viewpoints.

The information representing the view dependency between views refers to information that knows what structure the images between views are predicted. This may be obtained from the data region of the video signal, for example from the sequence parameter set region. The inter-view reference information may be determined using the number of reference pictures and the view information of the reference picture. For example, first, the number of all viewpoints may be obtained, and viewpoint information for distinguishing each viewpoint may be determined based on the number of all viewpoints. In addition, the number of reference pictures with respect to the reference direction may be obtained at each viewpoint. View information of each reference picture may be obtained according to the number of the reference pictures. In this manner, inter-view reference information may be obtained, and the inter-view reference information may be identified by being divided into an interview picture group and a non-interview picture group. This can be known using the interview picture group identification information indicating whether the coded slice currently in the NAL is an interview picture group.

The method of acquiring the global motion vector may vary according to the interview picture group identification information. For example, when the current picture is an interview picture group, the global motion vector may be obtained from the received bitstream. When the current picture is a non-interview picture group, the current picture may be derived from the global motion vector of the interview picture group.

In this case, in addition to the global motion vector of the interview picture group, information indicating a time distance may be used together. For example, referring to FIG. 5, when the global motion vector of Picture A is called GDVa and the global motion vector of Picture E is called GDVb, the global motion vector of the current picture C, which is a non-interview picture group, is the interview picture group. It can be obtained using the global motion vector and time distance information of the in-picture A and E. For example, the time distance information may be a picture order count (POC) indicating a picture output order. Therefore, the global motion vector of the current picture can be derived using Equation 3 below.

The block indicated by the global motion vector of the current picture thus derived can be regarded as a corresponding block for predicting coding information of the current block.

All motion information and mode information of the corresponding block may be used to predict coding information of the current block. The coding information may include various information necessary for coding the current block, such as motion information, information on illumination compensation, and weight prediction information. When the motion skip mode is applied to the current macroblock, the motion information of a picture that is already coded at another point in time may be used as the motion information of the current macroblock without coding the motion information of the current macroblock. In this case, the motion skip mode includes a case of acquiring motion information of a current block based on motion information of a corresponding block at a neighbor view. For example, when the motion skip mode is applied to the current macroblock, all the motion information of the corresponding block, for example, the macroblock type, the reference index, the motion vector, etc., are used as the motion information of the current macroblock. Can be utilized as However, the motion skip mode may not be applied in the following cases. For example, the current picture may be a picture at a reference point compatible with an existing codec, or an interview picture group. The motion skip mode may be applied to a case where a corresponding block exists in a neighbor view and the corresponding block is coded in an inter prediction mode. When the motion skip mode is applied, first, motion information of the List0 reference picture may be used according to the inter-view reference information, and motion information of the List1 reference picture may be used if necessary.

As described above, the decoding / encoding device to which the present invention is applied may be provided in a multimedia broadcasting transmission / reception device such as digital multimedia broadcasting (DMB), and may be used to decode a video signal and a data signal. In addition, the multimedia broadcasting transmission / reception apparatus may include a mobile communication terminal.

In addition, the decoding / encoding method to which the present invention is applied may be stored in a computer-readable recording medium that is produced as a program for execution on a computer, and multimedia data having a data structure according to the present invention may also be read by a computer. It can be stored in the recording medium. The computer readable recording medium includes all kinds of storage devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, and may also be implemented in the form of a carrier wave (for example, transmission over the Internet). Include. In addition, the bitstream generated by the encoding method may be stored in a computer-readable recording medium or transmitted using a wired / wireless communication network.

1 is a schematic block diagram of a video signal decoding apparatus to which the present invention is applied.

2 is a block diagram illustrating a method of performing motion compensation according to whether to skip motion according to an embodiment to which the present invention is applied.

3 is an embodiment to which the present invention is applied and is shown to explain a method of predicting motion information of a current unit.

FIG. 4 is an embodiment to which the present invention is applied and shows a method of deriving a view direction motion vector from units neighboring a current unit.

FIG. 5 is a diagram for describing a method of predicting coding information of a current block using inter-view correlation as another embodiment to which the present invention is applied.

Claims (15)

Determining whether to derive motion information of the current block; When the motion information of the current block is derived, deriving motion information of the current block by using motion information of a block neighboring the current block; And Performing motion compensation using the derived motion information of the current block Including but not limited to: When using the motion information of the neighboring block, it is determined whether the neighboring block refers to a picture at a different point in time. The method of claim 1, As a result of checking whether the neighboring block refers to a picture at another viewpoint, when only one neighboring block refers to a picture at another viewpoint, the motion vector of the neighboring block is predicted as the view motion vector of the current block. Video signal decoding method characterized in that. The method of claim 1, As a result of checking whether the neighboring block refers to a picture at a different point in time, when two or more neighboring blocks refer to a picture at a different point in time, the median value of the motion vectors of the neighboring blocks is determined as the motion direction vector of the current block. The video signal decoding method characterized in that the prediction. The method of claim 3, wherein If there is a neighboring block referring to a picture in a different time zone at the same time point among the neighboring blocks, the motion vector of the neighboring block is set to zero. The method of claim 1, And when the neighboring blocks all refer to pictures in different time zones at the same time point, predicting the view direction motion vector of the current block by using the motion vector of the interview picture group. The method of claim 5, And when there are a plurality of interview picture groups, a motion vector of a corresponding block in the interview picture group located closest in time to the current block is used. The method of claim 5, And the corresponding block is a block in the same position as the current block. The method of claim 5, And wherein the corresponding block is present at a position indicated by a temporal motion vector of the neighboring block. The method of claim 1, When the neighboring blocks all refer to pictures in different time zones at the same time and the current block does not refer to the interview picture group, the video motion decoding method of the current block is set to 0. . The method of claim 1, If the neighboring block is divided into partitions, the method may further include setting a motion vector of the neighboring block by using a motion vector of a partition block adjacent to the current block. Motion information of the current block is derived from the set motion vector of the neighboring block. The method of claim 10, And predicting an intermediate value of the set motion vectors of the neighboring blocks as a view motion vector of the current block. A motion skip determination unit for determining whether to derive motion information of the current block; A motion information derivation unit for deriving motion information of the current block by using motion information of a block neighboring the current block when deriving motion information of the current block; Motion compensation unit for performing motion compensation using the derived motion information of the current block Including but not limited to: And using the motion information of the neighboring block, checking whether the neighboring block refers to a picture at a different point in time. The method of claim 1, The video signal is received as a broadcast signal. The method of claim 1, And the video signal is received via digital medium. A computer-readable medium having recorded thereon a program for executing the method of claim 1.

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