Color signal decomposition method is to decompose the conventional three-primary colors(RGB) into the multiprimary control values of multi-primary display(MPD) under the constraints of tri-stimulus matching. For the satisfaction of tri-stimulus matching between input and output display systems, the MPD color signals have to be estimated from a deviceindependent color space such as CIEXYZ or CIELAB. However, as the target of MPD is to display moving-picture data, it is necessary to simplify the color space conversion between input and output systems and decomposition of the multi-primary control values. In this paper, color signal decomposition method for MPD is proposed using 3-dimensional look-up-table(3D-LUT) in linearized LAB space. The linearized LAB space satisfies the linearity and additivity in color space conversion and easily constructs the 3-D LUT considering lightness, chroma, and hue. For the reproduction of moving-picture data in MPD, the proposed method is based on 3-D LU...