14results about How to "Improve encoding/decoding efficiency" patented technology

The present invention relates to an image encoding / decoding method and a recording medium therefor. To this end, a method of decoding an image can include the steps of generating a list of a plurality of motion vector candidates according to an inter prediction direction of a current block, obtaining a plurality of motion vectors for the current block by using the list of the plurality of motion vector candidates, determining a plurality of prediction blocks for the current block by using the plurality of motion vectors, and obtaining a final prediction block for the current block based on the plurality of prediction blocks.

This invention provides a video signal decoding / encoding method and a bitstream transmission method. The video signal decoding method includes the following steps: determining an intra-frame prediction mode for a current block; obtaining reference samples based on neighboring samples of the current block; obtaining a first prediction sample for the current block based on the reference samples and the intra-frame prediction mode; obtaining a second prediction sample for the current block by applying weighted filtering to the reference samples and the first prediction sample; and obtaining a reconstructed sample for the current block based on the second prediction sample.

The video signal processing method and apparatus according to the present invention can determine the intra-prediction mode of the current block, determine the reference sample for intra-prediction of the current block, determine a predetermined matrix based on the intra-prediction mode, and predict the current block based on the reference sample and the matrix.

This invention relates to an image encoding / decoding method and a recording medium for the method. To this end, a method for decoding an image may include the following steps: generating a list of multiple motion vector candidates based on the inter-frame prediction direction of a current block; obtaining multiple motion vectors for the current block using the list of multiple motion vector candidates; determining multiple prediction blocks for the current block using the multiple motion vectors; and obtaining a final prediction block for the current block based on the multiple prediction blocks.

An image encoding / decoding method, a bit stream transmission method, and a computer-readable recording medium storing a bit stream are provided. An image decoding method according to the present disclosure comprises the steps of: acquiring a source picture timing information (SPTI) supplemental enhancement information (SEI) message; and reconstructing the image based on the SPTI SEI message, where the SPTI SEI message may include information about source picture timing for a picture associated with the SEI.

Image encoding / decoding methods and apparatus are provided. The image decoding method performed by the image decoding apparatus according to this disclosure includes the following steps: obtaining a first flag indicating the presence of Network Abstraction Layer (NAL) HRD parameters in the bitstream and a second flag indicating the presence of Video Coding Layer (VCL) HRD parameters in the bitstream; obtaining a third flag indicating whether the time interval between the output times of consecutive frames in the bitstream has a fixed value; deriving the output time of the frames in the bitstream based on at least one of the first, second, and third flags; and processing the frames in the bitstream based on the derived output times, wherein the first flag has a second value indicating that the NAL HRD parameters are not present in the bitstream and the second flag has a second value indicating that the VCL HRD parameters are not present in the bitstream, and the third flag can be restricted to having a first value indicating that the time interval between the output times of consecutive frames in the bitstream has a fixed value.

A video encoding method and apparatus are disclosed. An intra prediction method for video decoding includes determining an intra prediction mode belonging to an initial directional prediction range for an intra prediction of an MxN current block, determining whether to correct the intra prediction mode from the initial directional prediction range to a corrected directional prediction range based on a horizontal length N and a vertical length M of the MxN current block, determining a corrected intra prediction mode belonging to the corrected directional prediction range, and performing the intra prediction of the MxN current block based on the corrected intra prediction mode, the initial directional prediction range including a first prediction range, a second prediction range, and a third prediction range, the corrected directional prediction range including the first prediction range, the second prediction range, and a fourth prediction range according to the vertical length M, the intra prediction being performed by using reference regions adjacent to the current block, the reference regions including an upper reference pixel column and a left reference pixel column of the current block.

A method and apparatus for encoding / decoding an image are provided. A method for decoding an image according to the present disclosure can include the steps of obtaining a reconstructed image, determining a target boundary of deblocking filtering in the reconstructed image, determining a boundary strength of the target boundary, and applying deblocking filtering to the target boundary based on the boundary strength, wherein when the target boundary is a transform block boundary and a color component of the reconstructed image is a chroma component, the boundary strength can be determined based on whether joint CbCr residual coding is performed on at least one of two blocks adjacent to the target boundary, and the joint CbCr residual coding can correspond to encoding residual samples of a chroma Cb component and a chroma Cr component as a single transform block.

A video encoding method and apparatus are disclosed. An intra prediction method for video decoding, comprising: determining an intra prediction mode belonging to an initial directional prediction range for an intra prediction of an MxN current block; determining whether to correct the intra prediction mode from the initial directional prediction range to a corrected directional prediction range based on a horizontal length N and a vertical length M of the MxN current block; determining a corrected intra prediction mode belonging to the corrected directional prediction range; performing the intra prediction of the MxN current block based on the corrected intra prediction mode, the initial directional prediction range comprising a first prediction range, a second prediction range and a third prediction range, the corrected directional prediction range comprising the first prediction range, the second prediction range and a fourth prediction range according to the vertical length M of the MxN current block, the intra prediction of the MxN current block being performed by using a reference region adjacent to the MxN current block.

An encoding / decoding method, a bit stream transmission method, and a computer-readable recording medium storing a bit stream are provided. A method according to the present disclosure comprises the steps of: acquiring information on optimization applied to a video from a bitstream; and determining an optimization purpose and method based on the information about the optimization, where the information about the optimization may include first information indicating the optimization purpose and second information indicating a type of the optimization method.

The application relates to an image decoding method, an image encoding method, and a bitstream transmission method. An image encoding / decoding method and apparatus are provided. An image decoding method performed by an image decoding device according to the present disclosure comprises the steps of: determining a quantization parameter of a current block on the basis of whether color space conversion is applied to a residual sample of the current block; determining a conversion coefficient of the current block based on the quantization parameter; determining a residual sample of the current block using the conversion coefficient; and resetting the value of the residual sample based on whether the color-space conversion is applied.

The present invention proposes an image encoding / decoding method and device using intra prediction, and a video signal processing method and device according to the present invention can determine an intra prediction mode of a current block, determine a reference sample for intra prediction of the current block, and decode an image on the basis of the intra prediction mode. And determining a predetermined matrix, and predicting the current block based on the reference sample and the matrix.

A method and apparatus for image encoding / decoding using signals to notify HRD parameters, and a method for transmitting a bit stream are provided. The image decoding method according to this disclosure may include the following steps: obtaining first information indicating the number of one or more hypothetical reference decoder (HRD) parameter syntax structures within a video parameter set (VPS); obtaining one or more HRD parameter syntax structures from the VPS based on the first information; obtaining second information from the VPS related to the mapping between one or more multilayer output layer sets (OLS) and one or more HRD parameter syntax structures based on the first information; selecting an HRD parameter syntax structure to apply to the current OLS based on the second information; and processing the current OLS based on the selected HRD parameter syntax structure.

A method and apparatus for encoding / decoding an image are provided. A method for decoding an image according to the present disclosure can include the steps of obtaining a reconstructed image, determining a target boundary of deblocking filtering in the reconstructed image, determining a boundary strength of the target boundary, and applying deblocking filtering to the target boundary based on the boundary strength, wherein when the target boundary is a transform block boundary and a color component of the reconstructed image is a chroma component, the boundary strength can be determined based on whether joint CbCr residual coding is performed on at least one of two blocks adjacent to the target boundary, and the joint CbCr residual coding can correspond to encoding residual samples of a chroma Cb component and a chroma Cr component as a single transform block.