Abstract: An image decoding method and apparatus and an image encoding method and apparatus are discussed. The image decoding method can include deriving an intra prediction mode of a current block, deriving reference samples including left or upper reference samples for an intra prediction on the current block, and generating a predicted block by performing the intra prediction on the current block based on the intra prediction mode and the reference samples. Based on that the intra prediction mode of the current block is a DC mode and a height of the current block is equal to a width of the current block, the intra prediction of the current block is performed by using an average value of the left reference samples adjacent to a left boundary of the current block and the upper reference samples adjacent to an upper boundary of the current block.

Abstract: An image decoding method and apparatus and an image encoding method and apparatus are discussed. The image decoding method can include deriving an intra prediction mode of a current block, deriving reference samples including left or upper reference samples for an intra prediction on the current block, and generating a predicted block by performing the intra prediction on the current block based on the intra prediction mode and the reference samples. Based on that the intra prediction mode of the current block is a DC mode and a height of the current block is equal to a width of the current block, the intra prediction of the current block is performed by using an average value of the left reference samples adjacent to a left boundary of the current block and the upper reference samples adjacent to an upper boundary of the current block.

Abstract: An mage decoding method and apparatus and an image encoding method and apparatus are discussed. The image decoding method can include deriving an intra prediction mode of a current block, deriving reference samples being left or upper reference samples for an intra prediction on the current block, and generating a predicted block by performing the intra prediction on the current block based on the intra prediction mode and the reference samples. Based on that the intra prediction mode of the current block is a DC mode and a height of the current block is equal to a width of the current block, the intra prediction of the current block is performed by using an average value of the left reference samples adjacent to a left boundary of the current block and the upper reference samples adjacent to an upper boundary of the current block.

Abstract: An image decoding method can be performed by an image decoding apparatus. The image decoding method can include obtaining image information including prediction mode information for a current block, deriving a prediction mode of the current block based on the prediction mode information, deriving reference samples neighboring the current block, deriving prediction samples of the current block based on the prediction mode of the current block and the reference samples, and generating reconstructed samples of the current block based on the prediction samples. The reference samples include top reference samples of the current block and left reference samples of the current block. Further, whether a filtering is applied to the reference samples is determined based on the prediction mode of the current block and a size of the current block.

Abstract: The present invention relates to an intra prediction method and apparatus. The image decoding method according to the present invention may comprise decoding information on intra prediction; and generating a prediction block by performing intra prediction for a current block based on the information on intra prediction. The information on intra prediction may include information on an intra prediction mode, and the intra prediction mode may include a curved intra prediction mode.

Abstract: The present invention relates to an image encoding/decoding method and device. The image decoding method according to the present invention comprises the steps of: decoding a prediction mode index; determining whether the prediction mode index indicates function-based intra prediction; inducing a parameter (s) for generating a function, when the prediction mode index indicates the function-based intra prediction; generating the function on the basis of the induced parameter (s); and performing intra prediction by using the generated function.

Abstract: The present invention relates to an image encoding method and an image decoding method. The image decoding method includes partitioning a picture into a plurality of coding units, constructing a coding unit group including at least one coding unit of the plurality of coding units, obtaining coding information in units of one coding unit group, and decoding at least one coding unit of the plurality of coding units included in the coding unit group by using the obtained coding information.

Abstract: The present invention relates to an image encoding/decoding method and apparatus. An image encoding method according to the present invention may comprise generating a transform block by performing at least one of transform and quantization; grouping at least one coefficient included in the transform block into at least one coefficient group (CG); scanning at least one coefficient included in the coefficient group; and encoding the at least one coefficient.

Abstract: An image encoding/decoding method and apparatus for performing template matching-based intra prediction are provided. An image decoding method may comprise deriving a first intra-prediction mode for a current block, generating a first intra-prediction block corresponding to the first intra-prediction mode, deriving a second intra-prediction mode for the current block, generating a second intra-prediction block corresponding to the second intra-prediction mode, and generating a final intra-prediction block by using a weighted sum of the first intra-prediction block and the second intra-prediction block.

Abstract: The present invention relates to an intra prediction method and apparatus. The image decoding method according to the present invention may comprise decoding information on intra prediction; and generating a prediction block by performing intra prediction for a current block based on the information on intra prediction. The information on intra prediction may include information on an intra prediction mode, and the intra prediction mode may include a curved intra prediction mode.

Abstract: An image encoding/decoding method and apparatus for predicting a second color component block using a first color component block are provided. An image decoding method of the present invention comprises deriving a prediction parameter using the first color component block, and predicting the second color component block using the derived prediction parameter.

Abstract: An image encoding/decoding method and apparatus for performing intra prediction mode based intra prediction are provided. An image decoding method may comprise decoding an intra prediction mode of a current block, deriving at least one intra prediction mode from the decoded intra prediction mode of the current block, generating two or more intra prediction blocks using the intra prediction mode of the current block and the derived intra prediction mode, and generating an intra prediction block of the current block based on the two or more intra prediction blocks.

Abstract: The present invention relates to an intra prediction method and apparatus. The image decoding method according to the present invention may comprise decoding information on intra prediction; and generating a prediction block by performing intra prediction for a current block based on the information on intra prediction. The information on intra prediction may include information on an intra prediction mode, and the intra prediction mode may include a curved intra prediction mode.

Abstract: A clock recovery circuit is disclosed for recovering the data of a non-return to zero signal received at an optical transceiver. The clock recovery circuit includes an active element mixer for doubling the frequency of the received non-return to zero encoded digital signal. The mixer includes a delay element for delaying the received non-return to zero signal and an exclusive-OR circuit for exclusive-ORing the delayed and received non-return to zero signals. A SAW filter is also provided for recovering a clock from the frequency doubled signal outputted by the mixer.