Abstract: A method and an apparatus are disclosed for video coding using improved cross-component linear model (CCLM) prediction. The video coding method and the apparatus generate a first predictor of a current chroma block according to CCLM prediction, and additionally generate a second predictor of the current chroma block based on the neighboring pixels of the current chroma block in intra prediction of the current chroma block. The video coding method and the apparatus perform weighted combination on the first predictor and the second predictor.

Abstract: A video encoding method and a video decoding method are provided for adaptively determining a chroma intra-directional prediction mode. When a DM mode is applied for intra prediction of a chroma signal, the video encoding method and the video decoding method adaptively modify the directional mode of a luma block to conform to the characteristics of a chroma block by considering the position and size of the chroma block, the presence of reference samples, and the size of the luma block. The video encoding method and the video decoding method use the modified directional mode for intra prediction of the chroma signal.

Abstract: A method for decoding an image, according to the present invention, can comprise the steps of: drawing out a vector predictor of a block vector for indicating a reference block with respect to a current block to be predicted within a current picture; drawing out the block vector on the basis of the vector predictor and a vector differential value corresponding to a different value of the block vector and the vector predictor; and generating a prediction block with respect to the current block on the basis of the block vector.

Abstract: An image decoding method and an image decoding apparatus is provided. The method comprises recovering a first motion vector corresponding to a first decoding reference picture based on the entropy decoded bit stream, calculating a second motion vector corresponding to a second decoding reference picture by scaling the first motion vector based on a first temporal distance between the current picture and the first decoding reference picture and a second temporal distance between the current picture and the second decoding reference picture, generating a prediction block relating to a current block in the current picture, based on the calculated second motion vector, generating a residual block relating to the current block through a residual data decoding process based on the entropy decoded bit stream, and recovering the current block based on the prediction block and the residual block.

Abstract: The present specification discloses a method of decoding an image. The method of decoding an image according to the method includes: obtaining transform skip information of a current block from a bitstream; obtaining multiple transform selection information of the current block on the basis of the transform skip information from the bitstream; and performing inverse transform on the current block on the basis of the multiple transform selection information, wherein the multiple transform selection information is used to set each of a horizontal transform type and a vertical transform type.

Abstract: Disclosed herein are a video decoding method and apparatus and a video encoding method and apparatus. Coding decision information of a representative channel of a target block is shared as coding decision information of a target channel of the target block, and decoding of the target block is performed using the coding decision information of the target channel. Since the coding decision information of the representative channel is shared with an additional channel, repeated signaling of identical coding decision information may be prevented. By means of this prevention, the efficiency of encoding and decoding of the target block or the like may be improved.

Abstract: A method for decoding an image, according to the present invention, can comprise the steps of: drawing out a vector predictor of a block vector for indicating a reference block with respect to a current block to be predicted within a current picture; drawing out the block vector on the basis of the vector predictor and a vector differential value corresponding to a different value of the block vector and the vector predictor; and generating a prediction block with respect to the current block on the basis of the block vector.

Abstract: A method and an apparatus are disclosed for video coding using a block vector with an adaptive spatial resolution. The video coding method and the apparatus signal the spatial resolution of a block vector (BV) indicating the position of a reference block adaptively or signal the sign of a block vector difference adaptively in order to improve coding efficiency when intra block copy (IBC) is applied to a current block.

Abstract: A video coding method and an apparatus using an adaptive order of intra sub-partitions are provided. The video coding method and apparatus adaptively determine an encoding/decoding order of subblocks based on at least one of a shape of the subblock, a size of the subblock, a sub-splitting direction, and a prediction mode in performing intra prediction of the subblocks split from a current block using an ISP mode.

Abstract: An image decoding method for decoding a current block by using intra prediction includes: decoding information related to a chroma intra prediction mode of the current block from a bitstream; determining the chroma intra prediction mode by using a basic intra prediction mode set and an alternative mode according to a first luminance intra prediction mode corresponding to the current block and the related information; generating a prediction block of the current block by using the chroma intra prediction mode; reconstructing a residual block of the current block from the bitstream; and reconstructing the current block by adding the prediction block and the residual block. The alternative mode is adaptively determined.

Abstract: A video decoding method is disclosed for decoding a current block by using intra-prediction. The method includes: decoding related information including an intra-prediction mode of the current block from a bitstream; depending on the presence or absence of a reference sample at a position to be referenced in a first prediction direction indicated by an intra-prediction mode, determining a direction for the intra-prediction in consideration of a second prediction direction different than the first prediction direction; generating a prediction block of the current block by performing the intra-prediction according to the direction for the intra-prediction; reconstructing a residual block of the current block from the bitstream; and reconstructing the current block by adding the prediction block and the residual block.

Abstract: A method and an apparatus for video coding using intra sub-block prediction of a chroma block are disclosed. The video coding method and the apparatus adaptively apply a sub-block split method, transmission information, and a transform method in performing intra prediction on chroma signals of a current block using an intra sub-partitions (ISP) mode.

Abstract: A video coding method and apparatus adaptively determine spatial resolution for a horizontal component and a vertical component of a motion vector or block vector indicating a position of a reference block when performing inter prediction or intra block copy (IBC) of a current block. The video coding method and apparatus separately determine each spatial resolution for a plurality of motion vectors.

Abstract: A method and an apparatus for video coding using a video-characteristic-based context model are disclosed. The video coding method and the video coding apparatus determine a context model optimized for an individual video on the basis of information in which various characteristics of the individual video are reflected in entropy encoding and decoding using context adaptive binary arithmetic coding (CABAC).

Abstract: An image decoding method and an image decoding apparatus is provided. The method comprises recovering a first motion vector corresponding to a first decoding reference picture based on the entropy decoded bit stream, calculating a second motion vector corresponding to a second decoding reference picture by scaling the first motion vector based on a first temporal distance between the current picture and the first decoding reference picture and a second temporal distance between the current picture and the second decoding reference picture, generating a prediction block relating to a current block in the current picture, based on the calculated second motion vector, generating a residual block relating to the current block through a residual data decoding process based on the entropy decoded bit stream, and recovering the current block based on the prediction block and the residual block.

Abstract: The present specification discloses a method of decoding an image. The method of decoding an image according to the method includes: obtaining transform skip information of a current block from a bitstream; obtaining multiple transform selection information of the current block on the basis of the transform skip information from the bitstream; and performing inverse transform on the current block on the basis of the multiple transform selection information, wherein the multiple transform selection information is used to set each of a horizontal transform type and a vertical transform type.

Abstract: Disclosed are a method and an apparatus for image encoding/decoding. The method for image decoding includes comparing whether a size of a current transform block and a size of a smallest transform block (smallest transform unit (STU)) are the same as each other, and decoding information indicating whether transformation is performed on the current transform block and determining whether to perform inverse transformation on the current transform block based on the decoded information indicating whether the transformation is performed when the size of the current transform block and the size of a smallest transform block are the same as each other.

Abstract: A video encoding/decoding method and an apparatus using intra prediction per subblock basis are provided. The video encoding/decoding method and apparatus modify the intra prediction mode of a current block in a direction suitable for a subpartitioned block by considering the shape of the subpartitioned block, the direction of subpartitioning, and the prediction direction of the current block. Based on the modified intra prediction mode of the current block, the video encoding/decoding method and apparatus generate an intra prediction mode of the subpartitioned block to perform intra prediction per subblock basis effectively.

Abstract: Disclosed are a method and an apparatus for image encoding/decoding. The method for image decoding includes comparing whether a size of a current transform block and a size of a smallest transform block (smallest transform unit (STU)) are the same as each other, and decoding information indicating whether transformation is performed on the current transform block and determining whether to perform inverse transformation on the current transform block based on the decoded information indicating whether the transformation is performed when the size of the current transform block and the size of a smallest transform block are the same as each other.

Abstract: The present disclosure is related to a video encoding/decoding method and an apparatus using selective transmission of subblock partitioning information. The video encoding/decoding method and apparatus selectively encode and decode the splitting direction of a subblock to reduce the overhead of signal transmission for using subblock partitioning while effectively performing intra prediction per subblock basis.