Title:
EXPANDING/REDUCING METHOD FOR BINARY IMAGE
Document Type and Number:
Japanese Patent JPS62157468
Kind Code:
A
Abstract:
PURPOSE:To obtain an image close to an original half tone image by setting plural types of a scanning aperture, scanning on a dither image, counting the number of the white picture element in an equivalent scanning aperture and obtaining a presumed half tone image value. CONSTITUTION:Algorithm is used where in a low space frequency area (area where the picture element level change of a half tone image is small), a large aperture is selected and in a high space frequency area (area where the picture element change of the half tone image is large), a small aperture is selected, a scanning aperture D is a reference aperture first, processing is executed in the sequence of D C B A, and a suitable scanning aperture is selected. When the scanning aperture is not selected, the suitable aperture is selected in the route of D E G and D F G. Next, based on the ratio of the white area and the black area in the scanning aperture, a half tone image is presumed.
Inventors:
HIRATSUKA SEIICHIRO
MATSUNAWA MASAHIKO
ABE YOSHINORI
HASEBE TAKASHI
MATSUNAWA MASAHIKO
ABE YOSHINORI
HASEBE TAKASHI
Application Number:
JP29885385A
Publication Date:
July 13, 1987
Filing Date:
December 27, 1985
Export Citation:
Assignee:
KONISHIROKU PHOTO IND
International Classes:
H04N1/393; G06T3/40; (IPC1-7): H04N1/393
Attorney, Agent or Firm:
Ijima Fujiharu