Abstract:
Embodiments of the present disclosure provide a method and device for processing a video signal. A method for decoding an image signal according to an embodiment of the present disclosure comprises the steps of: determining a non-separable transform set index indicating a non-separable transform set used for a non-separable transform of a current block from among non-separable transform sets predefined on the basis of an intra-prediction mode of the current block; determining. as a non-separable transform matrix, a transform kernel indicated by a non-separable transform index for the current block from among transform kernels included in the non-separable transform set indicated by the non-separable transform set index; and applying the non-separable transform matrix to an upper left region which of the current block, which is determined according to the width and height of the current block, wherein each of the predefined non-separable transform sets includes two transform kernels.
Abstract:
Disclosed herein is a method for performing decoding using a Layered Givens Transform (LGT), which includes: deriving a plurality of rotation layers and at least one permutation layer, wherein the rotation layer includes a permutation matrix and a rotation matrix, and the rotation matrix includes at least one pairwise rotation matrix; acquiring an LGT coefficient using the plurality of rotation layers and the at least one permutation layer; and performing inverse transform using the LGT coefficient, in which the rotation layer may be derived based on edge information indicating a pair to which the at least one pairwise rotation matrix is applied.
Abstract:
The present disclosure provides a method for processing a video signal by using a linear relationship between transform types, the method comprising the steps of: determining a transform group on the basis of a prediction mode of a current block; parsing a transform combination index from the video signal, wherein the transform combination index indicates one of a plurality of transform combinations in the transform group; deriving a transform combination corresponding to the transform combination index, wherein the transform combination includes a horizontal transform and a vertical transform and includes DST-1 or DCT-5; performing inverse transform of the current block on the basis of the transform combination; and reconstructing the video signal by using the inverse-transformed current block.
Abstract:
The present invention provides a method for encoding a video signal comprising the steps of: obtaining activity information from the video signal, wherein the activity signal indicates information relating to edge characteristics of an image and includes edge orientation information and/or edge level information; determining conditionally non-linear transform (CNT) configuration information on the basis of the activity information; and performing CNT prediction coding on the basis of the CNT configuration information, wherein the CNT prediction coding involves performing prediction using all previously decoded pixel values.
Abstract:
An intra prediction method according to the present invention comprises the steps of: acquiring information on a luma prediction mode of a current block and information on a chroma prediction mode of the current block from a bit stream; deriving a luma intra prediction mode of the current block on the basis of the information on the luma prediction mode; determining a chroma intra prediction mode of the current block on the basis of information on the luma intra prediction mode and the information on the chroma prediction mode; and generating a chroma prediction sample of the current block on the basis of the chroma intra prediction mode. According to the present invention, it is possible to reflect the difference between the ratio of the width to the height of a luma component and the ratio of the width to the height of a chroma component, and thus to more accurately perform intra prediction in units of samples and improve intra prediction performance.
Abstract:
A video decoding method performed by a decoding apparatus includes the steps of: deriving control points (CP) for a current block; acquiring movement vectors for the CPs; deriving a sample unit movement vector in the current block on the basis of the acquired movement vectors; and deriving a prediction sample for the current block on the basis of the sample unit movement vector. According to the present invention, it is possible to effectively perform, through sample unit motion vectors, inter-prediction not only in a case where an image in the current block is plane-shifted but also in a case where there are various image distortions.
Abstract:
A method for decoding a video signal using a graph-based transform, the method being characterized by including the steps of: parsing a transform index from the video signal; obtaining context information for a target unit, where the context information includes a prediction mode for a current block or peripheral blocks; obtaining an inverse-transform kernel on the basis of at least one of the transform index and the context information; and performing an inverse transform for the current block using the inverse transform kernel.
Abstract:
The present invention relates to a method for encoding/decoding a still image or a video based on a polygon unit and an apparatus for supporting the same. Particularly, a method for encoding an image based on a polygon unit may include partitioning an input image by a unit of block, determining a position of at least one point within the block, determining a position of at least one point in each side of the block, partitioning the block into at least one polygon unit using a vertex of the block, at least two points among the points determined in the side of the block, and a point determined within the block and coding the input image by a unit of the polygon unit.
Abstract:
The present invention relates to a method and an apparatus for processing video signals, and more specifically, to a method and an apparatus for processing video signals which applies deformation compensation to decode a current texture block. The present invention can increase the accuracy of an inter-prediction by obtaining the position of a block within a reference picture referenced by the current texture block, by means of using deformation compensation parameter information, and obtaining a pixel value of the block within the reference picture that is obtained from a prediction value of the current texture block.
Abstract:
The video signal processing method according to the present invention comprises: generating a candidate mode list of a current block on the basis of an intra-prediction mode from the spatial neighboring block of the current block; modifying the candidate mode list on the basis of an intra-prediction mode from the neighboring view of the current block; inducing the intra-prediction mode of the current block on the basis of the modified candidate mode list; and predicting the current block by using the induced intra-prediction mode.