| 摘要 |
PURPOSE:To reproduce an image with fidelity to an original image even after the magnification processing of the image is performed by finding each density level and generating frequency of two picture elements interposing an interpolation point, and setting the density level of a point in which those take a value of 1/2 the sum of the products of each density level and generating frequency as the density level of the interpolation point. CONSTITUTION:Each density level and generating frequency of the two picture elements B, C on a third-order curve are checked, and the function f(x1) of the curve 31 representing them is found. The function f(x1) is integrated between the density level NB corresponding to the picture element B and the density level Nc corresponding to the picture element C, and the area S of an oblique line part is found, and next, the density level Np by which the area S is bi-sected is found. The density level Np goes to the analog value of the density level of the picture element P of the interpolation point, and the one quantized with a prescribed density level goes to the interpolation image data of the picture element P. In such a way, it is possible to reproduce the image with fidelity to the original image even after the magnification processing of the image is performed. |
