Typewriting machines – Including control of format by programmed-control-system
Reexamination Certificate
2006-04-11
2006-04-11
Chau, Minh (Department: 2854)
Typewriting machines
Including control of format by programmed-control-system
C400S070000, C400S062000, C358S003010, C358S003060, C358S003300
Reexamination Certificate
active
07025515
ABSTRACT:
A printing system is disclosed where a multi level pixel image (200) is converted into a half tone image (300) utilising a set of bit mask arrays (350-0to350-255) stored within a memory (310). The value of a multi level pixel is used to select one of the stored bit mask arrays. The co-ordinates of the multi level pixel in an image are then used to identify an entry from within the selected bit mask array. The identified entry is then used to set the value of the corresponding pixel in the half tone image. In order to reduce the appearance of contouring at the boundaries of adjacent portions of an image having similar grey levels, the stored bit mask arrays (350-0to350-255) are such that the majority of entries in the bit mask arrays for successive grey levels are identical. In addition to reducing contouring problems, the similarity of significant portions of bit mask arrays for successive grey levels make the bit mask arrays suitable for compression.
REFERENCES:
patent: 4805033 (1989-02-01), Nishikawa
patent: 4920501 (1990-04-01), Sullivan
patent: 5051844 (1991-09-01), Sullivan
patent: 5214517 (1993-05-01), Sullivan
patent: 5638188 (1997-06-01), Moro et al.
patent: 5673121 (1997-09-01), Wang
patent: 5822469 (1998-10-01), Silverstein
patent: 5956157 (1999-09-01), Tai
patent: 5978556 (1999-11-01), Wang
patent: 6118935 (2000-09-01), Samworth
patent: 6445465 (2002-09-01), Samworth
patent: 2003/0107768 (2003-06-01), Crounse
patent: 0504903 (1992-03-01), None
patent: 0734 149 (1996-09-01), None
patent: 1 282 107 (2003-02-01), None
patent: 1468741 (1974-03-01), None
patent: 2352 579 (2001-01-01), None
patent: 56123174 (1981-09-01), None
patent: 3187573 (1991-08-01), None
patent: 3187575 (1991-08-01), None
B. E. Bayer,An Optimum Method for Two-Level Rendition of Continuous-Tone Pictures, International Conference on Communications, vol. 1, pp. 26-11-26-15 (1973).
Robert W. Floyd and Louis Steinburg,An Adoptive Algorithm for Spatial Greyscale, Proc. SID, vol. 17(2), pp. 75-77 (1976).
R. L. Stevenson and G. R. Arce,Binary display of hexagonally sampled continuous-tone images, Journal of the Optical Society of America A, vol. 2(7), pp. 1009-1013 (1985).
Reiner Eschbach and Keith T. Knox,Error-diffusion algorithm with edge enhancement, Journal of the Optical Society of America A. vol. 8(2), pp. 1844-1850 (1991).
J. Sullivan, L. Ray and R. Miller,Design of Minimum Visual Modulation Halftone Patterns, IEEE Transactions on Systems, Man and Cybernetics, vol. 21(1), pp. 33-38 (1991).
Theophano Mitsa and Kevin J. Parker,Digital halftoning technique using a blue-noise mask, Journal of the Optical Society of America A, vol. 9(11), pp. 1920-1929 (1992).
Robert Ulichney,The void-and-cluster method for dither array generation, Human Vision, Visual Processing and Digital Display IV, Proc. SPIE, vol. 1913, pp. 332-343 (1993).
Kevin E. Spaulding, Rodney L. Miller and Jay Schildkraut,Recent Progress in Digital Halftoning II, IS&T, Springfield, VA, 1999, pp. 225-247.
Henry R. Kang, Xerox Corporation, Webster, New York. “Dispersed Micro-Cluster Halftoning”, Recent Progress in Digital Halftoning II, Chapter III, pp. 144-147.
Born Joseph H.
Chau Minh
Foley & Hoag LLP
Software 2000 Ltd.
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