Peano走査の一般化とハーフトーン処理への応用 : 映像表現,画像処理・コンピュータビジョン

抄録

The Peano scan is a path traversing an array of points and is very convoluted as a randam walk. This scan can be applied to sequential image transformation, instead of raster scan, and does not produce periodic patterns that are often observed in the case of raster scan. Also it is noted that the Peano scan has the same properties as that of quadtree or octree. If the distribution of values in a 2D or 3D array has clusters, then the clusters are preserved on the scan. This is the reason why this scan is applied to run-length compression and color quantization. The Peano scan, however, has restrictions in nature: the scanned array must be a square and the width and height must be a power of 2, because the scan is obtained by recursive division of the array, as quadtree. In the present article, some generalized Peano scans for any rectangular array are introduced, and halftoning is discussed as one of the applications of the Peano scans.