Hybrid interpolation and non-interpolation method and apparatus for

Abstract

Image data is processed to enlarge and contract an original image, represented by the data, by P times in an X-axis direction while the data is subjected to interpolation. The letter P denotes an arbitrary positive rational number. It is supposed that each of regions among pixels of the original image is divided into sub areas having a number of N by M, that is, N in the X-axis direction and M in a Y-axis direction. The letter N denotes an arbitrary integer equal to or greater than 2. The letter M denotes an arbitrary integer equal to or greater than 1. An N-time interpolation enlarging device or step serves to execute an interpolation process determined by an original-image sub area corresponding to a pixel of an enlargement/contraction-resultant image while simultaneously generating a plurality of pieces of process-resultant data representing a part of an image enlarged from the original image by N times in the X-axis direction. An arbitrary-magnification enlarging/contracting device or step serves to subject the plurality of the pieces of the process-resultant data to image enlargement and contraction at an arbitrary magnification in the X-axis direction without executing interpolation, and also serves to process the plurality of the pieces of the process-resultant data to enlarge and contract an image, represented by the plurality of the pieces of the process-resultant data, by P/N times in the X-axis direction.