Facsimile and static presentation processing – Facsimile – Specific signal processing circuitry
Patent
1989-01-24
1990-04-17
Britton, Howard W.
Facsimile and static presentation processing
Facsimile
Specific signal processing circuitry
358454, 358457, H04N 1032
Patent
active
049185438
ABSTRACT:
This invention relates to an apparatus for converting a grayscale image to a bitonal image which provides improved tonal rendition with minimal loss of resolution. The invention attenuates the low spatial frequency component of the digital image and uses a similarly attenuated thresholder to convert the image to a bitonal image. When used with a dither type thresholder, this technique allows for simultaneous "continuous tone" and "line art" thresholding with minimal circuit complexity.
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Arndt Dennis R.
Britton Howard W.
Eastman Kodak Company
Vu Kim Yen
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