Rehalftoning of gray halftones with optimal screen frequency...

Details Rehalftoning of gray halftones with optimal screen frequency... Rehalftoning of gray halftones with optimal screen frequency...

2006-11-07

2006-11-07

Lee, Thomas D. (Department: 2625)

Facsimile and static presentation processing

Static presentation processing

Attribute control

C358S003070

Reexamination Certificate

active

07133161

ABSTRACT:
Optimal rehalftone screen frequencies are found by searching frequency space for points that are maximally spaced from significant frequency components of an input image halftone screen or screens. Selecting a rehalftone screen having a maximally spaced frequency produces moiré of the highest frequency possible. High frequency moiré are visually unobjectionable. Optimal rehalftone frequencies may be found near the maximally spaced points where system or other constraints limit the usefulness of the maximally spaced points. Rehalftone screen frequencies in the range of about 1.4 to about 1.8 times the fundamental frequency of the input image halftone screen are often optimal. A rehalftone screen frequency of 1.5 times the fundamental frequency of the input image halftone screen is often optimal when the input image is monochrome and uses a dot screen.

REFERENCES:
patent: 4194221 (1980-03-01), Stoffel
patent: 4811115 (1989-03-01), Lin et al.
patent: 4941185 (1990-07-01), Reed
patent: 5293430 (1994-03-01), Shiau et al.
patent: 5341226 (1994-08-01), Shiau
patent: 6185328 (2001-02-01), Shiau
patent: 6347153 (2002-02-01), Triplett et al.
patent: 6549656 (2003-04-01), Lin
patent: WO 98/36555 (1998-08-01), None
D. Blatner, G. Fleishman and S. Roth,Real World Scanning and Halftones, 2nd Edition, 1988, p. 280.
Xiangdong Liu, Roger Ehrich, “Analysis of Moire Patterns in Non-Uniformly Sampled Halftones”,Applications of Computer Vision, 1996. WACV '96, Proceedings 3rdIEEE Workshop on Sarasota, Fl., USA Dec. 2-4, 1996, Los Alamitos, Ca, USA, IEEE Comput. Soc, US Dec. 2, 1996, pp. 208-213.
Joseph Shou-Pyng Shu, Robert Springer, Chia Lung Yeh, “Moire Factors and Visibility in Scanned and Printed Halftone Images”,Optical Engineering, Soc. of Photo-Optical Instrumentation Engineers, Bellingham, US, vol. 28, No. 7, Jul. 1, 1989, pp. 805-812.
Dimitri Van De Ville, Koen Denecker, Wilfried Philips, Ignace Lemahieu, “Nonlinear Resampling for Edge Preserving Moire Suppression”,Journal of Electronic Imaging, SPIE and IS&T, US, Oct. 2000, vol. 9, No. 4, pp. 534-547.
Arden Steinbach, K. Y. Wong, “An Understanding of Moire Patterns in the Reproduction of Halftone Images”, Computer Society Conference on Pattern Recognition and Image Processing, Chicago, U.S., Aug. 6-8, 1979, New York, IEEE, US, vol. Proc. 1979, pp. 545-552.
Thomas Scheermesser, Frank Wyrowski, Olof Bryngdahl, “Digital Halftoning Using Two-Dimensional Carriers with a Noninteger Period”,Journal of Electronic Imaging, SPIE and IS&T, U.S. Jan. 1995, vol. 4, No. 1, pp. 40-47.

Affiliated with

Also associated with

Rating

Rehalftoning of gray halftones with optimal screen frequency... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Rehalftoning of gray halftones with optimal screen frequency..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rehalftoning of gray halftones with optimal screen frequency... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3673879