A picture image editing system, incorporating a page memory device, having an editing subsystem and a boundary writing subsystem. The system is capable of writing desired boundary region data for at least some of the demarcating areas of a plurality of sets of picture image data to the page memory device, and of performing such writing operations in the course of or alternatively after the editing of the picture image data, such that boundary region data is present in a visually perceptible form, in a visually imperceptible form, or in a combination of both of these forms.