Intra prediction device, image encoding device, image decoding device, and program

Abstract

To provide an intra prediction device, an image encoding device, an image decoding device, and a program that can prevent an increase of additional information to be transmitted even when applying a cross-component linear model prediction (CCLM) thereto.SOLUTION: An intra prediction device performs intra prediction of a luminance block and a color difference block generated by dividing an image, and comprises a cross-component linear model prediction unit that predicts a color difference block from a decoded luminance block at a position corresponding to the position of the color difference block, by using a linear model calculated from reference pixels of the luminance and color difference of the periphery of the color difference block. The cross-component linear model prediction unit includes a reference pixel position selection unit that selects a linear model calculation pixel position that is the position of a reference pixel used for calculation of a linear model on the basis of a luminance intra prediction mode that is an intra prediction mode applied to intra prediction of the decoded luminance block.SELECTED DRAWING: Figure 4

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