Patent US6081345A successfully refreshed from Google Patents.
US6081345A
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Line screen having extended dynamic tone range for embedding machine readable data in halftone images
Assignee: Xerox Corp
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Filing: 1998-01-29
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Granted: 2000-06-27
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Expires: 2018-01-29
Abstract
Abstract A high performance halftone shape for embedding machine readable data in printed documents is based on a hyperbola to accommodate the embedded data over an extended dynamic tone range. The shape enables precise tone control and can used for color printing. By rotating the shape 45-degrees, two alternate "ortho-serpentine" structures can be constructed which can be added to the diagonal structures, creating an embedded data system with four orientations. The quadrature system also allows more and varied patterns, but has the disadvantage of additional noise.
Inventors
- 👤 Douglas N. Curry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:35
CPC Classifications
G; G06; G06T; G06T1/00; G06T1/0021; G06K; G06K1/00; G06K1/12; G06K1/121; G06K19/00; G06K19/06; G06K19/06009; G06K19/06018; H; H04; H04N; H04N1/00; H04N1/32; H04N1/32101; H04N1/32144; H04N1/32149; H04N1/32203; H04N1/32256; H04N2201/00; H04N2201/32; H04N2201/3201; H04N2201/3269; H04N2201/327
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
85 words
A method for embedding machine readable digital information in halftone images, said method comprising the steps of generating hyperbolic shapes for imparting a perceived tones to respective halftone cells in accordance with data samples that map into said tones, each of said shapes being symmetrical about a central axis of its receptive cell; and modulating the angular orientation of the axis of symmetry of at least some of said shapes in accordance with digital data values to embed said data values into the halftone image.
Claim 2
Independent Claim
85 words
A method for embedding machine readable digital information in halftone images, said method comprising the steps of generating hyperbolic shapes for imparting a perceived tones to respective halftone cells in accordance with data samples that map into said tones, each of said shapes being symmetrical about a central axis of its receptive cell; and modulating the angular orientation of the axis of symmetry of at least some of said shapes in accordance with digital data values to embed said data values into the halftone image.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-06-27 | 2003-12-27 | 2004-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-06-27 | 2007-12-27 | 2008-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-06-27 | 2011-12-27 | 2012-06-27 | $7700.00 | Window Closed / Lapsed |