Lg Electronics Inc.

Guangdong Oppo Mobile Telecommunications Corp., Ltd.

Vivo Mobile Communication Co., Ltd.

Seethal Paluri

Seunghwan Kim

Hendry Hendry

Jie Zhao

Seung Hwan Kim

Mehdi Salehifar

Jaehyun Lim

Moonmo Koo

Jane Zhao

Hyeong Moon Jang

Junghak Nam

Naeri Park

Hyeongmoon Jang

Jaeho Lee

Jung Hak Nam

Jungdong Seo

Seunghawan Kim

An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure may include: obtaining palette information and palette index prediction information of a current block from a bitstream; 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, wherein the palette predictor may be initialized using a user defined palette entry obtained from at least one of an adaptation parameter set (APS), a picture parameter set (PPS) or a slice header.

Image encoding/decoding method and apparatus using user-defined palette entry, and method for transmitting bitstream

A video decoding method performed by a video decoding device according to the present document may comprise the steps of: acquiring image information from a bitstream, the image information including a picture header associated with the current picture including a plurality of slices; parsing, from the picture header, at least one of a first flag indicating whether information necessary for an inter-prediction operation for a decoding process is present in the picture header, or a second flag indicating whether information necessary for an intra-prediction operation for the decoding process is present in the picture header; generating prediction samples by performing at least one of intra-prediction or inter-prediction for the slices in the current picture on the basis of at least one of the first flag or the second flag; and generating reconstructed samples on the basis of the prediction samples.

Method and device for processing image information for image/video coding

An image decoding method performed by a decoding apparatus, according to the present document, comprises the steps of obtaining residual information for a current chroma block; obtaining CU chroma QP offset-related information for the current chroma block on the basis of the size and tree type of the current chroma block; deriving transform coefficients for the current chroma block on the basis of the residual information; deriving chroma QP for the current chroma block on the basis of the CU chroma QP offset-related information; deriving residual samples for the current chroma block by dequantizing the transform coefficients on the basis of the chroma QP; and generating a reconstructed picture on the basis of the residual samples.

Image decoding method using chroma quantization parameter, and apparatus therefor

An image decoding method performed by a decoding device, according to the present document, comprises the steps of: obtaining image information through a bitstream; and generating a reconstructed picture on the basis of the image information.

Image decoding method and device therefor

An image encoding/decoding method and device are provided. An image decoding method performed by an image decoding device according to the present disclosure may comprise the steps of: determining a prediction mode of the current block on the basis of prediction information obtained from a bitstream; on the basis of the prediction mode of the current block, obtaining a flag indicating whether a color space transform is applied to a residual sample of the current block; determining a quantization parameter of the current block on the basis of the flag; and determining a transform coefficient of the current block on the basis of the quantization parameter.

Image encoding/decoding method and device using adaptive color transform, and method for transmitting bitstream

According to one embodiment of the present specification, provided is an image decoding method performed by a decoding device. The method comprises the steps of: acquiring, from a bitstream, image information comprising information related to decoder-side intra mode derivation (DIMD); determining, on the basis of the information related to DIMD, whether DIMD is applied to a current block; deriving DIMD modes for the current block on the basis that DIMD is applied to the current block; and generating a prediction sample for the current block on the basis of the DIMD modes.

Method and device for intra prediction based on plurality of DIMD modes

An image encoding/decoding method and apparatus are provided. An image decoding method performed by an image decoding apparatus may comprise parsing weight information specifying a weight for a reference sample from a bitstream according to a weight parameter syntax structure, and decoding a current block by performing inter prediction based on the weight information. The parsing according to the weight parameter syntax structure may comprise obtaining weight number information specifying the number of weight information obtained from the bitstream according to the weight parameter syntax structure and obtaining weight information from the weight parameter syntax structure based on the weight number information.

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

According to the disclosure of the present document, a quantization parameter for a quantized escape value in a palette mode can be derived on the basis of minimum quantization parameter information about a conversion skip mode to perform a scaling process on the quantized escape value. Therethrough, the data amount that is required to be signaled for palette mode coding can be reduced, and the efficiency of escape coding in the palette mode can be enhanced.

Image or video coding based on palette coding

According to the disclosure of the present document, information regarding ALF filter coefficients may be encoded/decoded by fixed order-based exponential golomb coding. In addition, information regarding a fixed filter in ALF may be binarized by fixed-length coding. Accordingly, signaling efficiency can be increased, and coding complexity can be decreased.

Adaptive loop filter-based video or image coding

A picture decoding method performed by a decoding apparatus according to the present disclosure includes obtaining motion prediction information from bitstream, generating an affine MVP candidate list including affine MVP candidates for a current block, deriving CPMVPs for respective CPs of the current block based on one of the affine MVP candidates included in the affine MVP candidate list, deriving the CPMVDs for the CPs of the current block based on information on CPMVDs for each of the CPs included in the obtained motion prediction information, deriving CPMVs for the CPs of the current block based on the CPMVPs and the CPMVDs, deriving prediction samples for the current block based on the CPMVs, and generating reconstructed samples for the current block based on the derived prediction samples.

Image coding method based on motion vector and apparatus therefor

A method and device for processing a video signal are disclosed. More specifically, a method of processing a video signal based on inter prediction may comprise: deriving a motion vector predictor based on motion information of a neighboring block of a current block; deriving a motion vector difference of the current block based on layer information and index information; deriving a motion vector of the current block based on the motion vector predictor and the motion vector difference; generating a prediction block of the current block based on the motion vector of the current block; and generating a reconstructed block of the current block based on the prediction block and a residual block of the current block, wherein the layer information includes at least one syntax element indicating a layer group to which the current layer belongs.

Method and apparatus for processing video signal on basis of inter prediction

A video decoding method performed by a video decoding device may include: parsing a first flag and a second flag from a bitstream, wherein the first flag is related to whether weighted prediction is applied to slices referring to a picture parameter set within the bitstream, and the second flag is related to whether information relating to the weighted prediction exists in a picture header within the bitstream; parsing a prediction weighted table syntax from the picture header based on the first flag and the second flag; generating prediction samples for a current block in a current picture based on syntax elements within the prediction weighted table syntax; generating residual samples based on residual information obtained from the bitstream; and generating reconstructed samples based on the prediction samples and the residual samples, wherein the second flag is parsed from the picture parameter set based on the first flag.

Method and device for weighted prediction for image/video coding

Provided are an image encoding/decoding method and device. An image decoding method performed by an image decoding device according to the present disclosure includes the steps of: determining a quantization parameter of the current block on the basis of whether color space conversion is applied to a residual sample of the current block; determining a transform coefficient of the current block on the basis of the quantization parameter; determining the residual sample of the current block by using the transform coefficient; and resetting the value of the residual sample on the basis of whether the color space conversion is applied.

Method and device for encoding/decoding image using color space conversion, and method for transmitting bitstream

Disclosed herein are an image encoding/decoding method and apparatus. An image decoding method performed by an image encoding apparatus may include acquiring size information indicating a size of a current slice corresponding to at least a portion of a current picture from a bitstream and determining the size of the current slice based on the size information.

Image encoding/decoding method and apparatus for selectively encoding size information of rectangular slice, and method for transmitting bitstream

A video decoding method executed by a video decoding apparatus according to the present document comprises the steps of: parsing a flag associated with weighted prediction from a bitstream; on the basis of the flag, parsing a prediction weighted table syntax from the bitstream; and on the basis of the prediction weighted table syntax, executing a weighted prediction on a current block in a current picture to reconstruct the current picture, wherein on the basis of the value of the flag being 1, the prediction weighted table syntax may be parsed from a picture header of the bitstream, and on the basis of the value of the flag being 0, the prediction weighted table syntax may be parsed from a slice header of the bitstream.

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Seoul, South Korea

Seethal Paluri