those having a level of u201c ff u201d in u201c light green u201d and those having a level of u201c 80 u201d in dark green next in step s 3 the pixel engine 6 submits the g plane comprising hexadecimal values as shown in fig8 to 4 neighbored laplacean filtering as shown in fig9 and stores the processed g plane into the color buffer the 4 neighbored laplacean filtering is a process in which as shown in fig9 a value of a target pixel p multiplied by a coefficient u2212 4 is compared with a sum of values of upper lower left and right adjacent pixels pu pd p 1 and pr around such target pixel p individually multiplied by a coefficient 1 and a difference calculated from the comparison is given as a value for such target pixel p that is the laplacean filtering is a calculation for obtaining the difference in luminance between a target pixel and the adjacent pixels thereof and can extract only portions such as the edge portion where a difference in luminance occurs between the adjacent pixels in a practical process of the laplacean filtering the image processing device switches the operational mode of the individual pixel data in the u03b1 blending between an addition mode and subtraction mode to thereby perform addition and subtraction while stepwisely advancing over the pixels in synchronization with the calculation of the laplacean filtering shown in fig9 although the present embodiment deals with 4 neighbored laplacean filtering it is also possible to adopt 8 neighbored laplacean filtering which involves 8 pixels located on the upper lower left right upper right lower right upper left.