| 摘要 |
PURPOSE:To detect the position of the center of gravity at a high speed with high accuracy by a reduced number of elements, by using a memory means and a multiplication means as a means for performing division when the center of gravity of brightness distribution is calculated to make it possible to substantially perform division. CONSTITUTION:In a divider 74, ROM 741 stores a value obtained by multiplying the reciprocal of each address by a definite value, for example, 232 in said address and, by inputting a brightness cumulative value to the address terminal thereof, the content of said address is read. A multiplier 742 inputs a primary moment cumulative value and the value read by ROM 741 to mutually multiply both values and takes out only the higher rank 32 bits among the output 64 bits thereof. The value thus obtained is equal to the value obtained by dividing the primary moment cumulative value by the brightness cumulative value. This value becomes the position of the center of gravity. By this constitution, it is unnecessary to actually divide the primary moment cumulative value by the brightness cumulative value and a division value is substantially obtained only by using a memory or multiplier having simple constitution. Therefore, this apparatus can be obtained by several ICs and can be operated at a high speed.
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