Lg Electronics Inc.

Guangdong Oppo Mobile Telecommunications Corp., Ltd.

Beijing Xiaomi Mobile Software Co., Ltd.

Tcl King Electrical Appliances (huizhou) Co. Ltd.

Hyeong Moon Jang

Jung Hak Nam

Nae Ri Park

Seung Hwan Kim

Jin Seong Heo

Hendry Hendry

Jaehyun Lim

Jangwon Choi

Sunmi Yoo Yoo

Seethal Paluri

Sangheon Lee

Jungah Choi

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

An image encoding/decoding method and apparatus are provided. An image decoding method performed by an image decoding apparatus may comprise determining a current block by splitting an image, identifying whether a palette mode is applied for the current block based on a palette mode flag obtained from a bitstream, obtaining palette mode encoding information of the current block from the bitstream based on a tree type of the current block and whether the palette mode is applied for the current block, and obtaining chroma component prediction information of the current block from the bitstream based on the palette mode being not applied for the current block.

Image encoding/decoding method and device for signaling chroma component prediction information according to whether palette mode is applicable, 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 prediction mode characteristic information based on a color format of a current block, determining a prediction mode type of a lower-layer block split from the current block based on the prediction mode characteristic information, obtaining the lower-layer block by splitting the current block based on the prediction mode type of the lower-layer block, and decoding the lower-layer block based on the prediction mode type of the lower-layer block. The prediction mode type of the lower-layer block comprises a first prediction mode type specifying that both an intra prediction mode and an inter prediction mode are available, a second prediction mode type specifying that only the intra prediction mode is available and a third prediction mode type specifying that only the inter prediction mode is available. Based on a first condition for the current block being satisfied, the prediction mode characteristic information has a first value, and the first condition comprises a case where a color format of the current block is a monochrome format or a 4:4:4 format. Based on the first condition for the current block being not satisfied, the prediction mode characteristic information has a second value or a third value based on at least one of a color format, split mode or size of the current block.

Image encoding/decoding method and device for determining division mode on basis of color format, and method for transmitting bitstream

An image encoding/decoding method and apparatus are provided. An image decoding method comprises determining whether a current entry in a reference picture list structure is an inter-layer reference picture (ILRP) entry, determining whether a current layer including a current picture has a plurality of direct reference layers, based on the current entry being the ILRP entry, acquiring a layer index of the current entry for a direct reference layer list from a bitstream, based on the current layer having a plurality of direct reference layers, and determining a direct reference layer including the current entry based on the layer index. The obtaining of the layer index may be skipped based on the current layer not having a plurality of direct reference layers.

Method and device for image encoding/decoding based on layer index of ILRP, 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 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 performed by an image decoding apparatus may comprise identifying a current chroma block by splitting an image, identifying whether a matrix based intra prediction mode applies to a first luma sample position corresponding to the current chroma block, identifying whether a predetermined prediction mode applies to a second luma sample position corresponding to the current chroma block, based on the matrix based intra prediction mode doing not apply, and determining an intra prediction mode candidate of the current chroma block based on an intra prediction mode applying to a third luma sample position corresponding to the current chroma block, based on the predetermined prediction mode doing not apply.

Image encoding/decoding method and apparatus for determining prediction mode of chroma block by referring to luma sample position, 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 comprises determining whether a prediction mode of a current block is an intra block copy (IBC) mode based on information on the prediction mode of the current block, based on the prediction mode of the current block being an IBC mode, deriving motion information of the current block based on motion information of a corresponding block corresponding to the current block, and generating a prediction block for the current block, by performing IBC prediction based on the derived motion information of the current block. Based on absence of motion information of the corresponding block, the motion information of the current block is derived based on default motion information.

Image encoding/decoding method and device using IBC prediction, and method for transmitting bitstream

An image encoding/decoding method and apparatus are provided. The image encoding method comprises deriving information for a composite picture generated from one or more source pictures and generating a bitstream by encoding a single composite picture information (CPI) supplemental enhancement information (SEI) message including the information for the composite picture. The composite picture may comprise one or more patches obtained from the source pictures, the information for the composite picture may comprise first information for a source area corresponding to each of the patches in the source pictures and second information for a patch area covered by each of the patches in the composite picture, and each layer including the source pictures may be an output layer.

Method and apparatus for encoding/decoding image on basis of CPI SEI message, and recording medium having bitstream stored therein

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 performed by an image decoding apparatus may comprise deriving a reconstructed block for a current block, deriving a target boundary for the reconstructed block, determining a filter length of a deblocking filter to be applied for the target boundary, and applying the deblocking filter for the target boundary based on the determined filter length. The filter length may be determined based on at least one of a width or height of a transform block adjacent to the target boundary.

Image encoding/decoding method and device using filtering, 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 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 performed by an image decoding apparatus may comprise obtaining palette information and palette index prediction information of a current block from a bitstream, based on a palette mode applying for the current block, constructing a palette predictor for the current block based on the palette information and constructing a palette table for the current block based on the palette predictor, generating a palette index map for the current block based on the palette index prediction information, and decoding the current block based on the palette table and the palette index map, The palette predictor may be selectively updated based on a split structure of the current block.

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Seoul, South Korea

Hyeong Moon Jang