Area localization process for mixed text/image processing on a picture-screen

摘要

A system for localizing a region of a display incorporates a plurality of resettable counters for defining the position and extent of a cursor in two dimensions, such cursor comprising at least two non-parallel lines defining an open frame. Data is set into the counters periodically at the beginning of each frame, or at the beginning of each scanning line, so that the size and shape of the cursor is selectable, as well as its position on the display. When the data is modified during successive time periods, the cursor can be made to progressively reduce its size so as to indicate a point, and/or to progressively change its location.