| 摘要 |
<p>A method for designating a rectangular area on a document includes the following procedure. During a first step, data of a pixel of concern and data of pixels adjacent thereto are read out from a first memory by scanning the memory in accordance with each of four combinations of main and sub scanning directions. Next, a first logic operation is carried out with respect to the pixel data. During a third step, a result of the first logic operation is stored in the first memory. Then, a second logic operation is performed on the result of the first logic operation which is obtained in each combination of the scanning directions. A group of results of the second logic operation with respect to each pixel represents the rectangular area which has the drawn figure as an inscribed figure and is filled with pixel data having a value identical to that of pixel data forming a contour image of the drawn figure. An apparatus for carrying out the method is also provided.</p> |
