(57) A method for displaying a picture image in which pixel data are divide into groups every 2^m of the data which are aligned sequentially, the pixel data of each of the divided groups are written into the same numbered addresses of memory elements of 2^m, and read out the 2^m pixel data in parallel, then the data are converted into parallel to series (vice versa) so that order of the data may be restored to the original order thereof. When the pixel data are written in the memory elements, every at least two consecutive addresses sequence of the consecutive 2m pixel data are changed according to accessed addresses and at least every two groups the identical specific numbered pixel data in the groups are controlled so that they may be written in different numbered memory elements with each other. In the case of reading out pixel data from the memory elements, data of 2^m read out of the memory elements of 2m by any consecutive addresses are rearranged according to the writing control in the case of normal display, and in 1/2" reduction display both vertical and horizontal addresses are multiplied by 2" according to 1/2" reduction, and the 2^m memory elements are read out basing on different 2" addresses obtained according to writing control.