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EP0642258A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Frequency modulated halftone image and method for making same

Assignee: Agfa Gevaert NV
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Filing: 1994-08-16
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Granted: —
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Expires: 2014-08-16
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Abstract

Abstract A frequency-modulation halftone image and method that enable the use of relatively large frequency-modulation halftone dots, which have desirable reprographic characteristics, in combination with high resolution rendering of text, graphics, and boundary information in general. <IMAGE>

Inventors

  • 👤 Paul C/O Agfa-Gevaert N.V. Delabastita
  • 👤 Frank C/O Agfa-Gevaert N.V. Deschuytere

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-09 20:25
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/405; H04N1/4051

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 46 words
A frequency-modulation halftone image (906) - generated by a frequency modulation halftone screening process from a contone image (902) - having a plurality of halftone dots at least some of which have a size greater than the size of one pixel (904) of said contone image.
Claim 2
Dependent Claim 31 words
The frequency-modulation halftone image of claim 1 wherein at least some of said plurality of halftone dots have a size equal to the size of one pixel of said contone image.
Claim 3
Independent Claim 110 words
A method for producing a frequency-modulation halftone image comprising the following steps : (A) rendering a contone image at a recorder pitch ; (B) storing said contone image as contone data values in a first memory store ; (C) generating threshold values at a resolution which is different from said recorder pitch ; (D) converting the resolution of said threshold values to said recorder pitch ; (E) comparing each of the contone data values of said first memory store in sequence with a corresponding threshold value ; and (F) storing the result of said comparison as a halftone data value in a second memory store, constituting the frequency-modulation halftone image.
Claim 4
Independent Claim 122 words
A method for producing a frequency-modulation halftone image comprising the following steps : (A) rendering a contone image at a recorder pitch ; (B) storing said contone image as contone data values in a first memory store ; (C) generating threshold values at a resolution which is different from said recorder pitch ; (D) converting said resolution of said threshold values to said recorder pitch ; (E) storing said converted threshold values in a matrix ; (F) comparing each of the contone data values of said first memory store in sequence with corresponding threshold values in said matrix ; and (G) storing the result of said comparison as a halftone data value in a second memory store, constituting the frequency-modulation halftone image.
Claim 5
Dependent Claim 13 words
The frequency-modulation halftone image produced by the method of claims 3 or 4.

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