| 摘要 |
<p>An image represented as an array of digitally valued picture elements is selectively reduced or expanded in size by the extraction or insertion of spaced apart rows and lines of picture elements, at positions which are the closest approximation to the newly scaled base, whether smaller or larger. In reproducing a given image, for example, the image may be concurrently or successively scanned by an array of photo detector elements and a plurality of digitally valued picture elements corresponding to grey scale values across the image, and distributed with a given resolution, may be generated. These values may be processed in real time, or stored in a comparable array for subsequent processing. In either event, the number of rows and lines in the array are modified in accordance with the desired scale factor, and these discrete changes are introduced at the closest approximation to optimum positions. In enlargement, the added lines are duplicative of the next adjacent line, whereas in reduction the lines are simply deleted and subsequent lines of picture elements are shifted to close the gaps and provide a continuous image. A dot generator array, such as an ink jet array, responsive to the digital values of the picture elements, operates in scanning fashion across a copy sheet and generates the image, at a modified scale factor in a single or in successive scans, which may occur at the same location or after transmission of the digitally valued picture data to a different location. However, other conventional image reproducing systems such as a cathode ray tube, electrostatic or thermal recording system may be utilized.</p> |
