Lg Electronics Inc.

University of Southern California

Industry-Academic Cooperation Foundation, Chosun University

Bumshik Lee

Sehoon Yea

Moonmo Koo

Kyuwoon Kim

Jin Seong Heo

Jaehyun Lim

Antonio Ortega

Hilmi Enes Egilmez

Hyeongmoon Jang

Eunyong Son

Yung-Hsuan Chao

Junghak Nam

Seungwook Park

Sunmi Yoo Yoo

Amir Said

The present invention provides a method for encoding a video signal based on an Edge Adaptive Graph-Based Transform (EA-GBT) including detecting a step edge or a ramp edge from a residual signal; generating a graph signal based on at least one of the step edge or the ramp edge; obtaining an EA-GBT coefficient by performing the EA-GBT for the graph signal; quantizing the EA-GBT coefficient; and entropy-encoding the quantized EA-GBT coefficient.

Method and apparatus for encoding/decoding video signal by using edge-adaptive graph-based transform

The present invention provides a method for decoding a video signal including extracting an inter prediction mode of a current block from the video signal; generating two non-square prediction blocks using two motion vectors according to the inter prediction mode; performing a non-square transform on the two non-square prediction blocks to obtain two non-square prediction blocks on a frequency domain; updating the two non-square prediction blocks on the frequency domain using a correlation coefficient or a scaling coefficient; and generating a reconstruction block based on the updated non-square prediction blocks on the frequency domain and a residual block.

Method and apparatus for encoding and decoding video signal using transform domain prediction for prediction unit partition

The present disclosure relates to a method for processing a video signal by using a linear relationship between transform types, 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 a video signal, wherein the transform combination index indicates anyone of a plurality of transform combinations in the transform group; deriving a transform combination corresponding to the transform combination index, wherein the transform combination consists of a horizontal transform and a vertical transform, and includes DST-7 or DCT-8; performing inverse transform on the current block on the basis of the transform combination; and restoring the video signal by using the inverse transformed current block.

Method and apparatus for performing low complexity computation in transform kernel for video compression

The present invention provides a method for encoding a video signal on the basis of a graph-based separable transform (GBST), the method comprising the steps of: generating an incidence matrix representing a line graph; training a sample covariance matrix for rows and columns from the rows and columns of a residual signal; calculating a graph Laplacian matrix for rows and columns on the basis of the incidence matrix and the sample covariance matrix for rows and columns; and obtaining a GBST by performing eigen decomposition of the graph Laplacian matrix for rows and columns.

Method and apparatus for encoding/decoding video signal by using graph-based separable transform

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.

Method and apparatus for performing low-complexity computation of transform kernel for video compression

An image decoding method performed by a decoding device according to the present invention comprises the steps of: deriving an intra prediction mode for a current PU on the basis of a received bit stream; and performing reconstruction of a plurality of TUs located in an area of the current PU on the basis of the intra prediction mode, wherein the step of performing reconstruction comprises, with respect to a current block that is one of the plurality of TUs, a step of deriving a prediction sample of the current block on the basis of a first reference sample located in a prediction direction of the intra prediction mode and a second reference sample located in an opposite direction of the prediction direction, and a step of reconstructing a block to be reconstructed on the basis of the prediction sample.

Image decoding method and device using intra prediction in image coding system

An intra prediction method according to the present invention comprises the steps of: determining an intra prediction mode for a current block; determining whether to apply a coefficient induced intra prediction (CIIP) to the current block; deriving neighboring reference samples for the current block on the basis of whether the CIIP is applied; and generating prediction samples for the current block on the basis of the intra prediction mode and the neighboring samples. The present invention can generate modified or improved neighboring reference samples and thereby can improve the performance of intra prediction.

Method and apparatus for coefficient induced intra prediction in image coding system

An intra-prediction method according to the present invention comprises the steps of: obtaining information on an intra-prediction mode from a bitstream; determining an intra-prediction mode for a current block on the basis of the information on the intra-prediction mode; determining whether to apply coefficient induced intra-prediction (CIIP) to the current block; deriving neighboring samples of the current block on the basis of the determination of whether to apply the CIIP; and generating predicted samples of the current block on the basis of the intra-prediction mode and the neighboring samples. According to the present invention, corrected or improved neighboring samples can be generated, whereby intra-prediction performance can be improved.

Intra-prediction method and apparatus in image coding system

A picture encoding method that includes selecting a Vbasis function for a current block according to a specific order from among basis functions; deriving a Vexpansion coefficient on the basis of the selected Vbasis function; calculating a Vweighted error criterion on the basis of the selected Vbasis function and the derived Vexpansion coefficient; and encoding and outputting information indicating the Vnumber as a basis number when the value of the Vweighted error criterion is less than a specific critical value.

Intra prediction method and apparatus for video coding

The present invention provides a method of decoding a video signal using graph-based transform comprising the steps: extracting prediction unit partition information of a current coding unit from the video signal; obtaining a graph-based transform kernel from predetermined table information based on the prediction unit partition information; and performing an inverse-transform of a transform unit using the graph-based transform kernel, wherein the graph-based transform kernel corresponds to at least one of the prediction unit partition information and an edge weight, and the edge weight is a predetermined value representing a correlation between pixels.

Method and apparatus for processing video signal using graph-based transform

The present invention provides a method for encoding a video signal comprising the steps of: performing block division with respect to a target unit of the video signal, wherein the block division is performed on the basis of square division and/or non-square division; determining the optimal block partition on the basis of a rate distortion cost, when the target unit is divided into a plurality of non-square blocks; and performing CNT prediction coding on the non-square blocks resulting from the optimal block partition, wherein the CNT prediction coding involves performing prediction using all previously decoded pixel values.

Method for encoding and decoding video signal, and apparatus therefor

The present invention provides a method for processing a video signal, comprising generating a prediction block for a neighbor block using a reconstructed reference pixel of the neighbor block when the neighbor block adjacent to a current block is intra-coded; determining a refined intra prediction mode of the neighbor block based on the prediction block, where the refined intra prediction mode represents a mode which minimizes an error between the prediction block and a reconstructed neighbor block; generating a prediction mode candidate list for the current block based on the refined intra prediction mode; selecting an intra prediction mode for the current block from the prediction mode candidate list; and performing a prediction for the current block based on the intra prediction mode.

Method and apparatus for encoding and decoding video signal

A method and a device for decoding a video signal using an adaptive separable graph-based transform. The method includes: receiving a transform index for a target block from the video signal in which the transform index indicates a graph-based transform to be applied to the target block; deriving a graph-based transform kernel corresponding to the transform index; and decoding the target block based on the graph-based transform kernel. The device includes: a parsing unit configured to receive a transform index for a target block from the video signal; and an inverse-transform unit configured to derive a graph-based transform kernel corresponding to the transform index and decode the target block based on the graph-based transform kernel.

Method and device for processing a video signal by using an adaptive separable graph-based transform

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.

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Seoul, South Korea

Bumshik Lee