Abstract: The present invention relates to an image encoding and decoding technique, and more particularly, to an image encoder and decoder using unidirectional prediction. The image encoder includes a dividing unit to divide a macro block into a plurality of sub-blocks, a unidirectional application determining unit to determine whether an identical prediction mode is applied to each of the plurality of sub-blocks, and a prediction mode determining unit to determine a prediction mode with respect to each of the plurality of sub-blocks based on a determined result of the unidirectional application determining unit.

Abstract: A method for decoding a target block which has been encoded in an intra block copy (IBC) mode. The method comprises: determining a partition type of the target block by decoding at least one of a first syntax element for determining a reference area to refer to in order to partition the target block and a second syntax element related to the partition type of the target block; decoding block vector information regarding one or more sub-blocks, which have been partitioned from the target block according to the partition type, and determining a block vector corresponding to each of the sub-blocks by using the block vector information; and predicting the target block by generating and combining one or more prediction blocks from a current picture in which the target block is located by using the block vector corresponding to each of the sub-blocks.

Abstract: The encoding/decoding method and apparatus according to the present invention derives a residual coefficient of a residual block, calculates a quantization parameter for a residual block, performs dequantization on a residual coefficient using a quantization parameter, and performs inverse transform on a dequantized residual coefficient to reconstruct a residual sample of a residual block.

Abstract: A block splitting structure is disclosed for efficient prediction and transform, and a method and an apparatus are disclosed for video encoding and decoding using the block Splitting structure. In particular, the method and apparatus are capable of splitting a video data block into two regions or blocks including an L-shaped block and a rectangular block and thus efficiently perform prediction on each block.

Abstract: A method and for reconstructing chroma blocks and a video decoding apparatus are disclosed. In accordance with one aspect of the present disclosure, provided is a method for reconstructing a chroma block of a target block to be reconstructed. The method includes decoding correlation information between first residual samples and second residual samples, the first residual sample, and prediction information of the chroma block from a bitstream, wherein the first residual samples are residual samples of a first chroma component and the second residual samples are residual samples of a second chroma component. The method further includes generating predicted samples of the first chroma component and predicted samples of the second chroma information on the basis of the prediction information, and deriving the second residual samples by applying the correlation information to the first residual samples.

Abstract: A method and an apparatus for video coding based on mapping are disclosed. The video coding method and the apparatus generate a prediction block of a current block with reference to a mapped image when a video encoding apparatus transmits mapping data related to a mapping of the image and a video decoding apparatus decodes the current block based on the mapping data.

Abstract: A method and an apparatus for video coding using derivation of intra prediction modes are disclosed. The video coding method and the video coding apparatus derive the intra prediction mode of a current block using pre-restored, neighboring reference sample values and generate a prediction block of the current block based on the derived prediction mode.

Abstract: The present invention relates to an apparatus and method for encoding and decoding an image by skip encoding. The image-encoding method by skip encoding, which performs intra-prediction, comprises: performing a filtering operation on the signal which is reconstructed prior to an encoding object signal in an encoding object image; using the filtered reconstructed signal to generate a prediction signal for the encoding object signal; setting the generated prediction signal as a reconstruction signal for the encoding object signal; and not encoding the residual signal which can be generated on the basis of the difference between the encoding object signal and the prediction signal, thereby performing skip encoding on the encoding object signal.

Abstract: An encoding/decoding device according to the present invention derives a residual coefficient of a residual block from a bitstream, calculates a quantization parameter for the residual block, performs inverse quantization on the residual coefficient by using the quantization parameter, and performs inverse conversion on the inversely quantized residual coefficient, thereby enabling restoration of a residual sample of the residual block.

Abstract: A method and apparatus for processing a video signal according to the present invention derives a first prediction value of a chrominance block using a sample of a luminance block, calculates a compensation parameter based on a predetermined reference area, derives a second prediction value of a chrominance block, and reconstructs a chrominance block based on a second prediction value of a chrominance block.

Abstract: The encoding/decoding method and apparatus according to the present invention derives a residual coefficient of a residual block, calculates a quantization parameter for a residual block, performs dequantization on a residual coefficient using a quantization parameter, and performs inverse transform on a dequantized residual coefficient to reconstruct a residual sample of a residual block.

Abstract: A method is provided for decoding a sequence of pictures using a gradual refresh technique. In particular, all areas in one picture are gradually encoded or decoded over a plurality of pictures associated with the picture.

Abstract: A method and apparatus for processing a video signal according to the present invention derives a first prediction value of a chrominance block using a sample of a luminance block, calculates a compensation parameter based on a predetermined reference area, derives a second prediction value of a chrominance block, and reconstructs a chrominance block based on a second prediction value of a chrominance block.

Abstract: The present invention relates to an image encoding and decoding technique, and more particularly, to an image encoder and decoder using unidirectional prediction. The image encoder includes a dividing unit to divide a macro block into a plurality of sub-blocks, a unidirectional application determining unit to determine whether an identical prediction mode is applied to each of the plurality of sub-blocks, and a prediction mode determining unit to determine a prediction mode with respect to each of the plurality of sub-blocks based on a determined result of the unidirectional application determining unit.

Abstract: There is provided an image decoding method comprising: deriving a first prediction value of a current block by using at least one sample included in a reference block, obtaining an illumination compensation parameter on the basis of a predetermined reference region, deriving a second prediction value of the current block by applying the illumination compensation parameter to the first prediction value and reconstructing the current block on the basis of the second prediction value.

Abstract: A method is provided for decoding a sequence of pictures using a gradual refresh technique. In particular, all areas in one picture are gradually encoded or decoded over a plurality of pictures associated with the picture.

Abstract: The present invention relates to an image encoding and decoding technique, and more particularly, to an image encoder and decoder using unidirectional prediction. The image encoder includes a dividing unit to divide a macro block into a plurality of sub-blocks, a unidirectional application determining unit to determine whether an identical prediction mode is applied to each of the plurality of sub-blocks, and a prediction mode determining unit to determine a prediction mode with respect to each of the plurality of sub-blocks based on a determined result of the unidirectional application determining unit.

Abstract: Disclosed are a method and an apparatus for patch book-based encoding and decoding of video data. A video data decoding method comprises the steps of: determining a patch book list for a block of video data; and determining one or more index values for the block. Each of the index values indicates a patch book entry having color values corresponding to a subset of pixels in the block, among patch book entries of the patch book list. The decoding method further comprises a step of reconstructing subsets of the pixels on the basis of the patch book list and the index values for the block.

Abstract: A video decoding method for decoding a target block using intra prediction comprises decoding, from a bitstream, boundary line information specifying at least one boundary line for partitioning the target block. The boundary line information allows partitioning the target block into a plurality of non-rectangular blocks. The method further comprises determining intra prediction modes for the non-rectangular blocks based on the boundary line information; generating a prediction block of the target block by performing intra prediction on each of the non-rectangular blocks using the intra prediction modes; reconstructing a residual block of the target block from the bitstream; and reconstructing the target block by adding the prediction block and the residual block.

Abstract: A method and an apparatus for parallel encoding and decoding of moving picture data are provided. The method includes decoding, from a bitstream, a syntax element indicating that a picture can be decoded using wavefront parallel processing and decoding encoded data of the picture. The step of decoding encoded data of the picture includes for a first coding block of a current CTU row encoded in a palette mode, predicting a palette table for the first coding block by using palette data from a first CTU of a previous CTU row and decoding the first coding block in the palette mode using the palette table predicted for the first coding block.