Method for automatic recognition of white blocks as well as text, graphics and/or gray image areas on a printed master

摘要

A method for automatic recognition of white blocks as well as text, graphics and/or gray image areas on a printed master employs the steps of optoelectronically scanning the master and converting the analog scanning signals into digital signals such that a binarily encoded representation of the master is generated. Horizontal and vertical white blocks are successively searched for in the binary image and the locations of such white blocks are stored. The binary image thus subdivided by horizontal white blocks and the binary image subdivided by vertical white blocks are logically linked to one another in order to locate white "frames" for the individual areas of the printed matter. Such printed master areas formed in white are subsequently statistically analyzed in order to determine whether the framed area represents a text, graphics or gray image area on the printed master.