| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a data processor for reducing a circuit scale when hardware is constituted and deriving a trigonometric function by simple addition/subtraction when software is constituted. <P>SOLUTION: A one-dimensional DCT device (800) for performing discrete cosine transform for a DCT block composed of 8×8 pixels is provided with: an input selective addition/subtraction part (810) for inputting pixel data f(0) to f(7), selecting a prescribed combination of the pixel data and adding/subtracting the pixel data of the prescribed combination; an initial value operation part (820) for calculating coefficients C1, C2 as initial values; coefficient operation parts (830, 840) for calculating coefficients C3 to C7 by recursively applying C<SB>n+1</SB>=2 cosβC<SB>n</SB>-C<SB>n-1</SB>; and an addition/subtraction selection part (850) for inputting the coefficients C1 to C7, selecting a prescribed combination of the coefficients, adding/subtracting the coefficients of the prescribed combination, and outputting DCT coefficient data F(0) to F(7). <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
