Lg Electronics Inc.

Beijing Xiaomi Mobile Software Co., Ltd.

Nae Ri Park

Hyeong Moon Jang

Jung Hak Nam

Hendry Hendry

Seung Hwan Kim

Byeong Moon Jeon

Seung Wook Park

Joon Young Park

Jae Hyun Lim

Yong Joon Jeon

Jung Sun Kim

Young Hee Choi

Chul Keun Kim

Jaehyun Lim

An image encoding/decoding apparatus and method are provided. An image decoding method performed by an image decoding apparatus according to the present disclosure may comprise deriving a motion shift of a current block using motion information of a neighboring block of the current block, determining a collocated block of the current block using the motion shift, deriving a motion vector for at least one control point (CP) of the determined collocated block, and deriving at least one control point motion vector (CPMV) of the current block using the motion vector for the at least one CP.

Image encoding/decoding method and device using affine TMVP, and method for transmitting bit stream

The present invention relates to an entropy encoding method, an entropy decoding method and to an apparatus using same. The entropy decoding method includes: a step of decoding a bin of a syntax element; and a step of acquiring information on the syntax element based on the decoded bin. In the step of decoding the bin, context-based decoding or bypass decoding is performed for each bin of the syntax element.

Entropy decoding method, and decoding apparatus using same

An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure is performed by an image decoding apparatus. The image decoding method may comprise deriving a prediction sample of a current block based on motion information of the current block, determining whether prediction refinement with optical flow (PROF) applies to the current block, deriving, based on that the PROF applies to the current block, a difference motion vector for each sample position in the current block, deriving a gradient for each sample position in the current block, deriving a PROF offset based on the difference motion vector and the gradient, and deriving a refined prediction sample for the current block based on the PROF offset.

Image encoding/decoding method and device for performing prof, and method for transmitting bitstream

An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure is performed by an image decoding apparatus. The image decoding method comprises deriving a first flag specifying whether to perform weighted prediction on a current block and a weight index BcwIdx of bi-prediction with CU-level weight (BCW) for the current block, determining whether to perform default weighted prediction or explicit weighted prediction on the current block based on the first flag and BcwIdx, and generating a prediction block for the current block by performing the determined method.

Image encoding/decoding method and device for performing prediction, and method for transmitting bitstream involving weighted prediction and bi-directional optical flow

An image encoding/decoding method and apparatus is provided. The image decoding method comprises determining whether first information specifying a value of a picture order count (POC) most significant bit (MSB) cycle of a current picture is present in a picture header, determining a POC MSB of the current picture based on whether the first information is present in the picture header, and deriving a POC of the current picture based on the determined POC MSB. Based on the first information being not present in the picture header and the current picture being not a CLVSS (coded layer video sequence start) picture, a POC difference between the current picture and a previous picture preceding the current picture in decoding order may be less than half a maximum value of a POC least significant bit (LSB) of the current picture.

Method and apparatus for image encoding/decoding on basis of POC MSB information, and recording medium for storing bitstream

An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure is performed by an image decoding apparatus. The image decoding method comprises deriving a prediction sample of a current block based on motion information of the current block, deriving a reference picture resampling (RPR) condition for the current block, determining whether prediction refinement with optical flow (PROF) applies to the current block based on the RPR condition, and deriving a refined prediction sample for the current block by applying PROF to the current block.

An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure is performed by an image decoding apparatus. The image decoding method comprises constructing a merge candidate list for a current block based on a prediction mode of the current block, deriving motion information of the current block based on the merge candidate list, and generating a prediction block of the current block based on the motion information. Information on a maximum number of merge candidates included in the merge candidate list may be obtained through a sequence parameter set, and, based on the prediction mode being a subblock-based merge mode, the maximum number of merge candidates may be determined based on whether an affine mode is available for the current block.

Image encoding/decoding method and apparatus, and method of transmitting bitstream using sequence parameter set including information on maximum number of merge candidates

An image coding/decoding method and device are provided. The image decoding method carried out by the image decoding device, according to the present disclosure, may comprise the steps of: determining the number of tiles in a current picture on the basis that the segmentation of the current picture is not restricted; on the basis that the number of tiles in the current picture is a plurality, acquiring from a bitstream, a first flag representing whether tile boundary filtering is available; and, on the basis of the value of the first flag, determining whether to carry out filtering for the boundaries of the tiles belonging to the current picture.

Image coding/decoding method and device for selectively signaling filter availability information, and method for transmitting bitstream

An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure is performed by an image decoding apparatus. The image decoding method may comprise deriving a prediction sample of a current block based on motion information of the current block, determining whether bi-directional optical flow (BDOF) applies to the current block, based on that the BDOF applies to the current block, deriving a gradient for a current subblock in the current block, deriving motion refinement (v, v) for the current subblock based on the gradient, deriving a BDOF offset based on the gradient and the motion refinement, and deriving a refined prediction sample for the current block based on the prediction sample of the current block and the BDOF offset.

Image encoding/decoding method and device for performing BDOF, and method for transmitting bitstream

An image encoding/decoding method and apparatus are provided. An image decoding method performed by an image decoding apparatus may comprise determining a motion vector and decoding a current block based on the motion vector. The motion vector may be determined based on at least one of a first reference picture type of a first reference picture corresponding to the current block or a second reference picture type of a second reference picture corresponding to an inter-layer corresponding block.

Image encoding/decoding method and device having motion information determined on basis of interlayer prediction, and method for transmitting bitstream

An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure may comprise constructing an affine merge candidate list for a current block, based on an inter prediction mode of the current block being an affine merge mode, selecting one affine merge candidate from the affine merge candidate list, deriving motion information of the current block based on motion information of the selected affine merge candidate, generating a prediction block of the current block based on the motion information of the current block, and reconstructing the current block based on the prediction block of the current block. The constructing the affine merge candidate list may comprise deriving a constructed affine merge candidate, and the deriving the constructed affine merge candidate may comprise deriving a weight index for bi-prediction of the constructed affine merge candidate.

Video encoding/decoding method and device for deriving weight index for bidirectional prediction of merge candidate, and method for transmitting bitstream

An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure is performed by an image decoding apparatus. The image decoding method comprises deriving a prediction mode of a current block, constructing a merge candidate list for the current block, based on the prediction mode of the current block being a triangle partition mode (TPM), deriving motion information of two partitions of the current block based on the merge candidate list and two merge indices of the current block signaled through a bitstream, generating a prediction block of the current block based on the motion information, storing motion information of the current block, and updating a history-based motion vector predictor (HMVP) buffer based on the motion information of the current block.

Image encoding/decoding method and device for performing prediction on basis of HMVP candidate, and method for transmitting bitstream

An image encoding/decoding method and apparatus are provided. An image decoding method performed by an image decoding apparatus includes determining whether predetermined splitting is allowed for a current block based on a size of the current block, obtaining information on splitting of the current block based on whether the predetermined splitting is allowed, splitting the current block based on the information on splitting of the current block, and decoding the current block. Whether the predetermined splitting is allowed may be determined based on whether a width or height of the current block is a predetermined sample length.

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Seoul, South Korea

Nae Ri Park