| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic focusing device and a method therefor by which focusing is stably performed without causing erroneous judgement by a subject or a photographing condition. SOLUTION: A subject frequency recognition circuit 118 is constituted of a frame memory, a two-dimension DCT unit, a grouping circuit, a weighting circuit, a pattern extraction circuit, a pattern memory, a comparator circuit, a frequency limit circuit, a one-frame delay circuit, an arithmetic operation circuit and a comparator circuit. In the case of discriminating it that the subject is a low-contrast subject as the recognized result by converting the subject image into a frequency component and also in the case the detected result of fluctuation is small, the subject is estimated as the lowcontrast subject, so that the characteristic of a BPF 110 is set to a full band and motor speed is set lower than standard ones. Meanwhile, in the case the detected result of the fluctuation is large, the subject is estimated as a low-illuminance subject, so that an AF evaluation value is averaged and the filter is set to a band where a high band is somewhat cut from the full band, and the motor speed is set low so that hill-climbing control may satisfactorily be performed even at the averaged AF evaluation value. |
