Facsimile and static presentation processing – Static presentation processing – Attribute control
Reexamination Certificate
2006-08-31
2008-11-25
Haskins, Twyler L. (Department: 2625)
Facsimile and static presentation processing
Static presentation processing
Attribute control
C358S003030, C358S003040, C358S003050, C358S534000, C358S003080, C382S252000, C382S275000
Reexamination Certificate
active
07457002
ABSTRACT:
An improved digital halftoning method that uses an input image's global gray levels to determine the local gray levels of a monochrome output image. Input multi-bit pixels grouped into two-pixel-by-two-pixel local subcells are variously aggregated into one or more larger supercells. The size of said supercell(s) is related to and limited by the size of the global input bitmap. A final monochrome gray level is derived from said supercell(s) and distributed within contained subcells. Subcell gray levels are expressed as interim whole monochrome pixels and gray level remainders. A comparison is made of the final supercell and the summed interim subcell monochrome gray levels. An ordering of the remainders is used for assignment of additional monochrome pixels, if necessary, to yield final subcell monochrome gray levels. Gray level rounding errors thus are quantized by reverse diffusion until a monochrome gray level for each of the global image's two-pixel-by-two-pixel local subcells is derived.
REFERENCES:
patent: 6002493 (1999-12-01), Case
patent: 7079290 (2006-07-01), Crossland et al.
patent: 7265875 (2007-09-01), Kress
patent: 2003/0081256 (2003-05-01), Wang et al.
Villarreal, “Quality and Compressibility of Checkerboard-Based Digital Halftoning Algorithms,” Thesis, Master of Science in Computer Science, Southwest Texas State University, 2002, pp. 47-56.
Adler, et al, “The Mathematics of Halftoning,” International Business Machines Journal of Research and Development, vol. 47, No. 1, 2003, pp. 5-15.
Floyd, et al.: “An Adaptive algorithm for Spatial Grayscale”, Society for Information Display Symposium, Digest of Technical Papers, 1995, pp. 36-37.
Haskins Twyler L.
Skyward Optics LLC
Zheng Jacky X
LandOfFree
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