| 摘要 |
To extract a target object having a desired size from a bidimensonal image, horizontal direction filtering suppresses image components less than the desired size in the horizontal direction and thereby outputs a result of horizontal filtering. At the same time, vertical direction filtering suppresses image components less than the desired size in the vertical direction and thereby outputs a result of vertical filtering. The results of the horizontal and vertical filtering are superposed to produce a final filtered result corresponding to the target object. During the filtering, pixel data making up the bidimensonal image are sequentially connected in the vertical or horizontal direction in a preselected connecting area to produce gradation sequence of the pixels and then subjected to FFT to transform the gradation sequence into frequency domain and to thereby frequency selection to select desired harmonics components corresponding to the target object from the FFT result. |
