KR20080007177A - A method and apparatus for processing a video signal - Google Patents

Abstract

A method and an apparatus for processing a video signal are provided to improve the efficiency of signal processing by predicting movement information through spatial correlation of image sequence and improve the restoring ratio due to calculating the movement information similar to the movement information of the block. A video signal processing method comprises a step of determining one of a list 0 disparity vector and a list 1 disparity vector of an image block, co-located with respect to a pair prediction image block, as a disparity vector for inducing disparity vectors of the pair prediction image block. A picture, indicated by list 0 disparity vector or the list 1 disparity vector, includes a picture of a view different from the pair prediction image block.

Description

A method and apparatus for processing a video signal

The present invention relates to a method and apparatus for processing a video signal.

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. Furthermore, there is a multi-view video image as a field of three-dimensional (3D) image processing that provides a user with various viewpoints using one or more cameras. Since such multi-view video images have a high correlation between viewpoints, redundant information can be removed through spatial prediction between viewpoints. Therefore, various compression techniques are needed to efficiently perform prediction between viewpoints.

An object of the present invention is to provide a method and apparatus for efficiently processing multi-view image data.

Another object of the present invention is to efficiently process a video signal by providing a method for predicting coding information of the video signal.

Another object of the present invention is to efficiently process a video signal by providing a method for predicting motion information.

In order to achieve the above object, the present invention determines one of the list 0 motion vector and the list 1 motion vector of the image block at the same position with respect to the bi-prediction image block as a motion vector for deriving the motion vectors of the bi-prediction image block. And the picture indicated by the list 0 motion vector or the list 1 motion vector comprises a picture at a different point of view than the bi-prediction image block.

In addition, the present invention provides a video signal processing method characterized in that when the determined motion vector points to a picture at a different point in time, a motion vector indicating a position difference according to a camera arrangement is derived by camera information.

According to the present invention, signal processing efficiency can be improved by predicting motion information using temporal and spatial correlation of an image sequence. In addition, by predicting coding information of a current block by using coding information of a picture having a high correlation with the current block, prediction can be performed more accurately, and an 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 using the camera information can be predicted more accurately, and the amount of data transmission can be reduced accordingly to perform 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.

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 predictor 700 includes an illumination difference predictor 710, an illumination compensator 720, a motion compensator 730, and the like.

The parsing unit 100 performs parsing on a NAL basis 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. Since MVC is an additional technology to the existing AVC technology, 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 temporal level information, view level information, inter-view picture group identification information, view identification information, and the like.

The parsed bitstream is entropy decoded by 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. The intra prediction unit 400 performs intra prediction from the decoded samples in the current picture by using the reconstructed pixel value. 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 picture. 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. The reference pictures managed as described above may be used by the inter prediction unit 700.

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 predictor 700 includes an illumination difference predictor 710, an illumination compensator 720, a motion compensator 730, and the like.

When the input bitstream corresponds to a multi-view image, since the view sequences are images obtained from different cameras, illumination differences may occur due to internal and external factors of the camera. In order to prevent this, the illumination compensation unit 720 performs illumination compensation. In performing lighting compensation, flag information indicating whether lighting compensation is performed on a predetermined layer of a video signal may be used. For example, lighting compensation may be performed using flag information indicating whether lighting of the slice or the macroblock is performed. In addition, in performing lighting compensation using the flag information, it may be applied to various types of macroblocks (eg, inter16 × 16 mode, B-skip mode, or direct mode).

The motion compensator 730 compensates for the motion of the current block by using the information transmitted from the entropy decoder 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. 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 information identifying a 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. When this temporal direct mode is used in multi-view video coding, the inter-view motion vector must be taken into account. This will be described in detail with reference to FIGS. 2 to 8.

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 view illustrating a motion vector prediction method in consideration of a view direction as an embodiment to which the present invention is applied.

The direct prediction mode indicates a mode for predicting motion information of the current block from motion information of the encoded block. For example, in the direct prediction mode, a picture having the smallest reference number among List1 reference pictures may be defined as an anchor picture. The reference picture nearest to the current picture in the picture output order may be the anchor picture. The block of the anchor picture at the same co-located position as the current block may be defined as an anchor block. In the direct temporal prediction mode, the motion information of the current block may be predicted using the motion information of the anchor block. The motion vector in the List0 direction of the anchor block may be defined as mvCol. At this time, if there is no motion vector in the List0 direction of the anchor block and there is a motion vector in the List1 direction, the motion vector in the List1 direction may be mvCol. Here, in the case of the B picture, any two chapters may be used as reference pictures regardless of temporal or spatial front and back, and the prediction used at this time is called List0 prediction or List1 prediction. For example, List0 prediction may mean prediction for the forward direction, and List1 prediction may mean prediction for the backward direction.

In the temporal direct prediction mode, the List0 reference picture of the current block becomes the picture referenced by the mvCol, and the List1 reference picture becomes the anchor picture. When the anchor block does not have intra-picture coded motion information, the size of the motion vector is 0, and the reference picture number is 0 in List0 reference picture in temporal direct prediction mode.

Further, the motion vector mvL0 of List0 and the motion vector mvL1 of List1 can be obtained from the motion vector mvCol. Assuming that the velocity of motion is constant between the reference picture, the current picture, and the anchor picture, the sizes of mvL0 and mvL1 are proportional to the time distances of the reference picture, the current picture, and the anchor picture. Therefore, mvL0 and mvL1 can be obtained by proportional allocation. For example, mvL0 and mvL1 can be obtained by using a gap between the reference picture and the current picture and a gap between the reference picture and the anchor picture.

As another embodiment of the present invention, when performing inter-view prediction in multi-view video coding, compression efficiency may be improved by using a temporal direct prediction mode. That is, it may be applied when the List0 direction reference picture of the anchor block is a picture that is different from the viewpoint of the current picture. For example, referring to FIG. 2, first, C is the current picture, D is the anchor picture, A is a picture of another viewpoint referred to by the motion vector of the anchor block, and A is the same time as the picture referenced by the motion vector of the anchor block. Let B be a picture at the same time as the current picture. The pictures B, C, and D are present at the same time Va, respectively, on time Ta, Tb, and Tc. The picture A is present at a time point Vb different from the pictures B, C, and D, and is on time Ta.

In this case, when defining the motion vector in the List0 direction of the anchor block as mvCol, the picture A referred to by the mvCol is the picture A at a viewpoint Vb different from the viewpoint Va of the current picture C. Can be. In addition, the picture A may exist in different time zones or may exist in the same time zone. When present in the same time zone, the motion vector may include a global motion vector. As described above, the anchor picture may be defined as a reference picture that is closest to the reverse direction of the current picture in the picture output order. In addition, a block of an anchor picture that is co-located with the current block may be defined as an anchor block. Here, the co-located block may mean a block adjacent to a current block existing in the same picture or may be a block existing at the same position as the current block included in another picture. For example, another picture at a different point in time may be referred to as a spatial co-located block, and another picture at a same point in time may be referred to as a temporal co-located block. It may be.

The picture B at the same time Ta as the picture A referred to by the mvCol and at the same time as the view Va of the current picture may be referred to as a List0 reference picture of the anchor block. Since the picture A and the picture B exist at different viewpoints, there may be a difference between the viewpoints. This is defined as a disparity vector or a first motion vector. The disparity vector may mean a disparity difference between objects or pictures between two different viewpoints, or may mean a global disparity vector. Here, the motion vector may correspond to a partial region (for example, a macroblock, a block, a pixel, etc.), and the global disparity vector may mean a motion vector corresponding to the entire region including the partial region. The entire area may correspond to a macroblock, slice, picture, or sequence. In some cases, the image may correspond to one or more object areas and a background in the picture.

Therefore, in order to use the direct temporal prediction mode in multi-view video coding, the disparity vector may be applied to mvCol, which is a motion vector in the List0 direction of the anchor block. In this case, the motion vector in the List0 direction of the anchor block to which the disparity vector is applied may be defined as mvCol '. The List0 direction motion vector mvL0 of the current block and the List1 direction motion vector mvL1 of the current block can be obtained from the motion vector mvCol '. Similarly, assuming that the velocity of motion is constant between the reference picture (B), the current picture (C), and the anchor picture (D), the magnitudes of mvL0 and mvL1 are the reference picture (B), the current picture (C), and the anchor. It is proportional to the time distance of the picture D. Therefore, mvL0 and mvL1 can be obtained by proportional allocation. For example, mvL0 and mvL1 can be obtained using the time intervals Tb-Ta of the reference picture and the current picture and the time intervals Tc-Ta of the reference picture and the anchor picture. This will be described in detail later with reference to FIG. 3.

3 is a diagram for describing a method of predicting a motion vector of a current block in consideration of a view direction as another embodiment to which the present invention is applied.

When the direct temporal prediction mode is used, as shown in FIG. 2, the list vector direction motion vector mvL0 of the current block and the list1 direction motion vector mvL1 of the current block can be obtained from the motion vector mvCol 'considering the view direction. FIG. 3 is a view of FIG. 2 from the time axis. Hereinafter, various embodiments will be described.

1) For example, the List0 reference index of an anchor block refers to a long-term reference picture.

In this case, if the List0 reference picture referred to by the motion vector mvCol of the anchor block is at a different view from the current block, a disparity vector that is a disparity difference between views may be applied. In addition, since the List0 reference index of the anchor block refers to the long-term reference picture, the time distance between the current picture and the anchor picture is relatively close to zero. Therefore, mvL0 and mvL1 can be obtained through Equation 1 below.

mvL0 = mvCol + dv = mvCol '

mvL1 = 0

However, if the List0 reference picture referenced by the motion vector mvCol of the anchor block is at the same view as the current block, the disparity vector, which is the difference between the views, may not be applied. In this case, mvL0 and mvL1 can be obtained through Equation 2 below.

mvL0 = mvCol

mvL1 = 0

2) For example, the List0 reference index of the anchor block does not refer to the long-term reference picture.

In this case, if the List0 reference picture referred to by the motion vector mvCol of the anchor block is at a different view from the current block, a disparity vector that is a disparity difference between views may be applied. Since the List0 reference index of the anchor block does not refer to the long-term reference picture, mvL0 and mvL1 can be obtained using a proportional relationship of time distances. Equation 3 below may be used.

mvL0 = (mvCol + dv) * (tb / td) = mvCol '* (tb / td)

mvL1 =-(mvCol + dv) * (td- tb) / td = mvL0-(mvCol + dv)

     = mvL0-mvCol ’

However, if the List0 reference picture referenced by the motion vector mvCol of the anchor block is at the same view as the current block, the disparity vector, which is the difference between the views, may not be applied. In this case, mvL0 and mvL1 can be obtained through Equation 4 below.

mvL0 = mvCol * (tb / td)

mvL1 =-mvCol * (td- tb) / td = mvL0-mvCol

As described above, although the motion vector mvCol of the anchor block refers to a picture at another point in time, the reference picture list of the current picture may not include the picture at the other point of view. In this case, a block corresponding to the reference block at the other time point, for example, a block of a picture present at the same time and at the same time point as the current picture may be used. In this case, the corresponding block may be obtained using the disparity vector.

However, when the motion vector (mvCol) of the anchor block refers to a picture at a different point in time but the disparity vector is not available, mvL0 and mvL1 can be obtained without using the disparity vector. In this case, mvL0 and mvL1 may be obtained in the same manner except for the concept of the disparity vector in Equations 1 to 4. However, the reference picture number may be different because the picture that is on the same view as the current picture is used instead of the reference picture indicated by the mvCol.

In addition, as another embodiment to which the present invention is applied, camera information may be used when predicting a motion vector of a current block in consideration of a view direction. This will be described in detail with reference to FIGS. 4 to 5.

4 and 5 illustrate an embodiment to which the present invention is applied to explain a method of predicting a motion vector of a current block using camera information.

4 and 5, since the cameras are generally photographed in a horizontally arranged state, a motion vector between pictures having different viewpoints generally has only a component in a horizontal direction (x direction). exist. Here, when the horizontal motion vector is DVx, it is caused by the motion difference between the object and the background in the picture having different viewpoints. However, when the cameras are not in a straight line, the epipolar line (the line following the same point in the real object) (E1, E2, E3) is not parallel as shown in Figs. 4 and 5. In order to obtain a more accurate motion vector according to the position of the block (particularly in the block near E1 or E3), the motion vector in the vertical direction (y direction) as well as the horizontal motion vector must be considered. Here, when the vertical motion vector is DVy, this is caused by the position difference according to the camera arrangement. For example, the current block (cur) in FIG. 4 (a) is out of the epipolar line, whereas the block (ref) indicated by the motion vector having a component in the horizontal direction is in the epipolar line in FIG. 4 (b). Because it exists in, it does not match the actual. That is, the motion vector in the vertical direction may be calculated in order to obtain a motion vector dv indicating a corresponding block ref that matches the actual one. In this case, the value of the motion vector in the vertical direction may vary for each block.

The inter-view motion vector dv of the current block may be obtained using Equation 5 using the horizontal motion vector and the vertical motion vector.

dv (x, y) = DVx + DVy

In this case, the horizontal motion vector DVy may be obtained using camera information. Here, the camera information is information about a camera generating a sequence that is a series of pictures, and the series of pictures captured by one camera may constitute one viewpoint. Alternatively, a new viewpoint may be configured even when the position of the camera is changed.

Meanwhile, the types of camera information may include 1) camera parameters, 2) homogeneous matrices, 3) camera matrices, and 4) basic matrices. 6 to 8 will be described in detail below.

6 to 8 illustrate embodiments to which the present invention may be applied to illustrate types of camera information.

Camera parameters can include intrinsic camera parameters and non-native camera parameters, including intrinsic camera parameters, which include focal length, aspect ratio, and skew. There may be a principal point or the like, and the non-unique camera parameter may include camera position information in a world coordinate system.

The homogeneous matrix is for converting a specific view x into an ordered view x 'of the world coordinate system, as shown in Figures 6 and 6.

Where x 'is a point in the world coordinate system, x is a point in the local coordinate system of each view, and H is a homogeneous matrix.

A camera matrix describes a relationship between a local coordinate system and a world coordinate system in each view, and this relationship may be expressed as shown in FIG. 7 and equation (7).

Where x is a point in the local coordinate system of the current view, X is a point in the world coordinate system, and P is a camera matrix. The camera matrix P may be expressed by Equation 8 using camera parameters.

Where A denotes a unique parameter of the current camera, R denotes rotation, and t denotes translation. When the vector A is expressed in detail in Equation 8, Equation 9 is obtained.

Here, r is an aspect ratio, s is a skew, f is a focal length, and x ₀ and y ₀ are principal points.

A fundamental matrix describes a geometric relationship between a pair of viewpoints, and may be expressed as shown in FIG. 8 and Equation 10. FIG.

Where x 'and x are points in each local coordinate system, and F is a base matrix. And, the base matrix can be obtained through intrinsic camera parameters and extrinsic camera parameters of both cameras.

The motion vector DVy in the vertical direction may be obtained based on the camera information. The vertical motion vector DVy may be used in the direct temporal prediction mode considering the view direction. Hereinafter, various embodiments will be described.

1) For example, the List0 reference index of an anchor block refers to a long-term reference picture.

In this case, when the List0 reference picture referred to by the motion vector mvCol of the anchor block is a picture that is different from the current block, the horizontal motion vector DVx and the vertical motion vector DVy may be applied. have. In addition, since the List0 reference index of the anchor block refers to the long-term reference picture, the time distance between the current picture and the anchor picture is relatively close to zero. Therefore, mvL0 and mvL1 can be obtained through Equation 11 below.

mvL0 = mvCol + DVx + DVy = mvCol ''

mvL1 = 0

However, if the List0 reference picture referenced by the motion vector mvCol of the anchor block is at the same view as the current block, the motion vector DVx + DVy between the views may not be applied. In this case, mvL0 and mvL1 can be obtained through Equation 12 below.

mvL0 = mvCol

mvL1 = 0

2) For example, the List0 reference index of the anchor block does not refer to the long-term reference picture.

In this case, if the List0 reference picture referred to by the motion vector mvCol of the anchor block is a picture at a point in time different from the current block, the motion vector DVx + DVy between the viewpoints may be applied. Since the List0 reference index of the anchor block does not refer to the long-term reference picture, mvL0 and mvL1 can be obtained using a proportional relationship of time distances. Equation 13 below may be used.

mvL0 = (mvCol + DVx + DVy) * (tb / td) = mvCol '' * (tb / td)

mvL1 =-(mvCol + DVx + DVy) * (td- tb) / td = mvL0-(mvCol + DVx + DVy)

     = mvL0-mvCol ''

However, if the List0 reference picture referenced by the motion vector mvCol of the anchor block is at the same view as the current block, the motion vector DVx + DVy between the views may not be applied. In this case, mvL0 and mvL1 can be obtained through Equation 14 below.

mvL0 = mvCol * (tb / td)

mvL1 =-mvCol * (td- tb) / td = mvL0-mvCol

As described above, although the motion vector mvCol of the anchor block refers to a picture at another point in time, the reference picture list of the current picture may not include the picture at the other point of view. In this case, a block corresponding to the reference block at the other time point, for example, a block of a picture present at the same time and at the same time point as the current picture may be used. In this case, the corresponding block may be obtained using the motion vector DVx + DVy. The inter-view motion vector DVy value in the vertical direction may be obtained by the camera information.

In another embodiment to which the present invention is applied, the motion vector may be predicted using both the inter-view motion vector described with reference to FIG. 2 and the inter-view motion vector DVy in the vertical direction described with reference to FIG. 5. This is applicable in a manner similar to that described with reference to FIGS. 2 to 8.

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 view illustrating a motion vector prediction method in consideration of a view direction as an embodiment to which the present invention is applied.

3 is a diagram for describing a method of predicting a motion vector of a current block in consideration of a view direction as another embodiment to which the present invention is applied.

4 and 5 illustrate an embodiment to which the present invention is applied to explain a method of predicting a motion vector of a current block using camera information.

6 to 8 illustrate embodiments to which the present invention may be applied to illustrate types of camera information.

Claims (12)

Determining one of a list 0 motion vector and a list 1 motion vector of the image block at the same position with respect to the bipredicted image block as a motion vector for deriving the motion vectors of the bipredicted image block; And the picture indicated by the list 0 motion vector or the list 1 motion vector includes a picture at a different point in time than the bi-predicted image block. The method of claim 1, wherein the video signal processing method comprises: Deriving a list 0 motion vector and a list 1 motion vector of the bi-prediction image block from the determined motion vector The video signal processing method further comprising. The method of claim 2, And a list 0 motion vector and a list 1 motion vector of the bi-prediction image block are derived using a disparity vector between viewpoints. The method of claim 1, wherein the video signal processing method comprises: When the determined motion vector indicates a picture at a different viewpoint, acquiring a first motion vector indicating a difference between the viewpoints of the bi-predictive image block and the other viewpoint; The video signal processing method further comprising. The method of claim 4, wherein the video signal processing method comprises: Deriving a list 0 motion vector and a list 1 motion vector of the bi-prediction image block from the determined motion vector and the first motion vector. The video signal processing method further comprising. The method of claim 4, wherein And if the first motion vector is not available, list 0 motion vector and list 1 motion vector of the bi-prediction image block are derived from the determined motion vector. The method of claim 4, wherein Acquiring a second motion vector indicating a position difference according to a camera arrangement when the determined motion vector points to a picture at a different point in time The video signal processing method further comprising. The method of claim 7, wherein And the second motion vector is derived by camera information. The method of claim 8, And the camera information comprises at least one of a camera parameter, a homogeneous matrix component, a camera matrix component, and a base matrix component. The method of claim 1, And said at least one image block is associated with a list 1 reference picture. The method of claim 1, wherein the video signal processing method comprises: Determining a reference picture indicated by the determined motion vector as a list 0 reference picture The video signal processing method further comprising. The method of claim 1, wherein the video signal processing method comprises: Determining a list 0 reference picture from reference information of the co-located image block including the determined motion vector The video signal processing method further comprising.

Images