CROSS-REFERENCES TO RELATED APPLICATION

The present application claims the benefit of Korean application number 10-2017-0110978, filed on Aug. 31, 2017, which is herein incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field

The present invention relates to a method for constructing a tile structure and an apparatus therefor, and more particularly, to a method for constructing a tile structure having various types, and apparatus therefor.

2. Description of the Related Art

Recently, the demand for high resolution, and high quality pictures such as HD (High Definition) pictures and Ultra High Definition (UHD) pictures is increasing in various applications. As picture data becomes high resolution and high quality, the amount of data relatively increases as compared with the existing picture data. Therefore, when a picture data is transmitted by using a medium such as a conventional wired/wireless broadband line or stored by using an existing storage medium, transmission cost and storage cost will increase. High-efficiency picture compression techniques may be used to solve these problems caused by high resolution and high quality picture data.

In video compression techniques, motion prediction is used to remove temporal redundancy between successive pictures. In order to detect temporal redundancy, the motion of the current block is predicted by using a plurality of reference pictures, and motion compensation is performed to generate a predicted block. The motion information includes at least one reference picture index and at least one motion vector. In addition, in order to obtain motion information, the current block may obtain spatial motion information candidates and/or temporal motion information candidates from spatial neighboring blocks and/or temporal neighboring blocks.

Also, in HEVC, a technique called as a tile partitioning method is employed, which splits an image into rectangular regions (tiles) and independently performs encoding and decoding of individual regions. As described above, since the amount of data increases as the current image becomes higher resolution and higher quality, it is necessary to study a method of adaptively coding an image by utilizing a large amount of data in a part of the image as needed. To this end, the utilization of coding of a video signal using a tile may be increased, and an improvement on coding using such a tile may also be required.

The object to be realized by the present invention is to provide a tile structure configuration method and apparatus thereof to improve the coding efficiency of an image by configuring a tile having a structure of various types.

In addition, another object of the present invention is to provide a method for configuring a slice in a tile and an apparatus thereof, in which a plurality of slices constituting a tile have various types of structures, thereby improving coding efficiency.

In addition, another object of the present invention is to provide a method and apparatus thereof for constructing a slice in a tile that improves coding efficiency by scan the coding tree blocks and/or coding blocks in a tile according to an adaptively changeable order.

SUMMARY OF THE INVENTION

In a method for constructing a tile structure according to an embodiment of the present invention for solving the above problems, the current picture includes at least two or more tiles, the at least two or more tiles are split by a column splitting and a row splitting, at least one or more of the column splitting and the row splitting may be split by using a splitting length of at least one of which is shorter than the height length or the width length of the current picture.

In one embodiment, the method may include a step for determining the column splitting and the row splitting by using at least any one or more of a tile number information, a tile size information, a split direction information, a split region number information, a tile merge flag information, a tile merge number information, a tile index information, a tile position in formation, a tile width size information, and a tile height size information.

Further, the step for determining the column splitting and the row splitting may include: a step for dividing the current picture into at least two or more tiles by receiving the split direction information and the first split region number information; a step for receiving a second split region number information for each of the split tiles; and a step for subdividing the split tiles in a direction perpendicular to the split direction indicated by the dividing direction information, based on the second split region number information.

In one embodiment, the step for subdividing the split tile is repeated, and the step for subdividing may subdivide the tile in a direction perpendicular to the direction split in the previous splitting step. Further, the step for determining of the column splitting and the row splitting may include: a step for firstly dividing the current picture into at least two or more tiles by using the split direction information and the split region number information; and a step for merge at least two or more tiles of the firstly split tiles by using at least one or more of the tile merge flag information, the merge number information, and the tile index information.

The step for determining of the column splitting and the row splitting may include: a step for receiving the tile number information indicating the number of tiles to be split in the current picture; and a step for receiving the tile position information indicating the position of the tile indicated by the tile number information, the tile width size information indicating the width of the tile, and the tile height size information indicating the tile height size information.

In an embodiment, the method of the present invention includes a step for splitting the current picture into at least two or more tiles by using the tile number information, the tile position information, the tile width size information, and the tile height size information.

According to another embodiment of the present invention for realizing another object, there is provided a method for configuring a slice in a tile, wherein at least one or more tiles included in the current picture include at least two or more slices, and a boundary of the slice may be a vertical direction or a diagonal direction.

In one embodiment, the tile may have a variable scan order for each tile, and the variable scan order may be any one of a raster scan, a vertical scan, a horizontal scan, a diagonal scan, and a predetermined scan, and applied to a coding tree block included in the tile, and the variable scan order may be different for each tile.

Further, in one embodiment, the variable scan order may be dependent on the split direction of at least two or more slices of the tile, or independent of the split direction of at least two or more slices of the tile.

According to another embodiment of the present invention to realize another object, there is provided a decoding method of a coding tree block, wherein a current picture includes a plurality of coding tree blocks, the coding tree block includes a plurality of coding blocks, and the decoding order of the coding blocks can be determined for each of coding tree blocks.

In one embodiment, at least one or more tiles included in the current picture may include at least two or more slices, and a decoding order of the coding blocks may depend on a split direction of a slice in the tile.

According to an embodiment of the present invention, the present invention provides a method of constructing a tile structure, which configure tiles having various types of structures to improve coding efficiency of an image, and in which at least two or more tiles included in the current picture are split by using a column splitting or a row splitting, which is at least one or more splitting lengths shorter than the vertical or width length of the current picture, and an apparatus thereof.

In addition, according to another embodiment of the present invention, there is provided a method of configuring a slice in a tile and an apparatus thereof in which a coding efficiency may be increased by determining the boundaries of at least two or more slices constituting a tile in the vertical or diagonal direction, and a coding efficiency is improved according to a picture by scanning the coding tree blocks or the coding blocks for respective tile according to an adaptive scanning method.

