Image encoding/decoding method and device

Patent metadata

Field	Value
Publication number	US-12262002-B2
Application number	US-202418678368-A
Country	US
Kind code	B2
Filing date	May 30, 2024
Priority date	Mar 25, 2018
Publication date	Mar 25, 2025
Grant date	Mar 25, 2025

Abstract

An image prediction method according to the present invention may comprise: identifying a reference pixel region designated for obtaining correlation information; determining a reference pixel processing configuration on the basis of determination of the availability of the reference pixel region; and performing intra prediction according to the determined reference pixel processing. As described above, performing intra prediction on the basis of the availability of a reference pixel according to the present invention can improve encoding performance.

First claim

The invention claimed is:

1. A method of decoding an image performed by an image decoding apparatus including a prediction unit, the method comprising:
checking a reference pixel region used for obtaining correlation information for a current chroma block;
determining a reference pixel processing setting based on an availability of the reference pixel region;
down-sampling a luma block corresponding to the current chroma block;
deriving the correlation information based on the reference pixel region;
performing intra prediction according to the determined reference pixel processing setting for generating a prediction block of the current chroma block; and
reconstructing the current chroma block based on the prediction block,
wherein the current chroma block is predicted by applying the correlation information to the down-sampled luma block,
wherein the reference pixel region includes at least one of a neighboring region of the current chroma block or a neighboring region of the luma block,
wherein a number of reference pixel lines belonging to the reference pixel region used for deriving the correlation information is adaptively determined based on whether the current chroma block is located on a boundary of a maximum coding block,
wherein the neighboring region includes an above neighboring region and a left neighboring region of the current chroma block, and
wherein the correlation information is derived based on a maximum value derived using at least one reference pixel included in the reference pixel region.

2. A method of encoding an image performed by an image encoding apparatus including a prediction unit, the method comprising:
checking a reference pixel region used for obtaining correlation information for a current chroma block;
determining a reference pixel processing setting based on an availability of the reference pixel region;
down-sampling a luma block corresponding to the current chroma block;
deriving the correlation information based on the reference pixel region;
performing intra prediction according to the determined reference pixel processing setting for generating a prediction block of the current chroma block; and
encoding the current chroma block based on the prediction block,
wherein the current chroma block is predicted by applying the correlation information to the down-sampled luma block,
wherein the reference pixel region includes at least one of a neighboring region of the current chroma block or a neighboring region of the luma block,
wherein a number of reference pixel lines belonging to the reference pixel region used for deriving the correlation information is adaptively determined based on whether the current chroma block is located on a boundary of a maximum coding block,
wherein the neighboring region includes an above neighboring region and a left neighboring region of the current block, and
wherein the correlation information is derived based on a maximum value derived using at least one reference pixel included in the reference pixel region.

3. A method of transmitting a bitstream performed by an image encoding apparatus including a prediction unit, the method comprising:
encoding an image to generate the bitstream; and
transmitting the bitstream to an image decoding apparatus,
wherein the encoding the image comprises,
checking a reference pixel region used for obtaining correlation information for a current chroma block;
determining a reference pixel processing setting based on an availability of the reference pixel region;
down-sampling a luma block corresponding to the current chroma block;
deriving the correlation information based on the reference pixel region;
performing intra prediction according to the determined reference pixel processing setting for generating a prediction block of the current chroma block; and
encoding the current chroma block based on the prediction block,
wherein the current chroma block is predicted by applying the correlation information to the down-sampled luma block,
wherein the reference pixel region includes at least one of a neighboring region of the current chroma block or a neighboring region of the luma block,
wherein a number of reference pixel lines belonging to the reference pixel region used for deriving the correlation information is adaptively determined based on whether the current chroma block is located on a boundary of a maximum coding block,
wherein the neighboring region includes an above neighboring region and a left neighboring region of the current block, and
wherein the correlation information is derived based on a maximum value derived using at least one reference pixel included in the reference pixel region.

Assignees

• B1 Institute Image Technology Inc

Inventors

• Kim Ki Baek

Classifications

• H04N19/30

  using hierarchical techniques, e.g. scalability (H04N19/63 takes precedence) · CPC title

• H04N19/186

  the unit being a colour or a chrominance component · CPC title

• H04N19/176

  the region being a block, e.g. a macroblock · CPC title

• H04N19/593

  involving spatial prediction techniques · CPC title

• H04N19/124

  Quantisation · CPC title