US5740279A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cluster dot halftoning system
Assignee: Xerox Corp
•
Filing: 1996-11-26
•
Granted: 1998-04-14
•
Expires: 2016-11-26
Abstract
Abstract A method of constructing a screen for halftoning a digitized image is described, in which a composite screen is established. A composite LUT having m times n rank ordered threshold elements is constructed for use in halftoning digitized images. A variety of optimization techniques can be employed to improve the visual appeal of the images rendered using the composite LUT for rendering a variety of image types in single or multicolored imaging applications.
Inventors
- 👤 Shen-ge Wang
- 👤 Tse-kee Chan
- 👤 Fritz F. Ebner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:08
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/405; H04N1/4051; H04N1/46; H04N1/52
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
66 words
A method of constructing a composite screen for halftoning a digitized image, comprising: selecting a cluster screen halftoning system having a cell size of m cluster pixels; selecting a stochastic screen halftoning system size having a set of n stochastic pixels; and merging the set of n pixels and m pixels into a composite stochastic screen of halftone cluster LUT having a set of threshold elements.
Claim 2
Independent Claim
66 words
A method of constructing a composite screen for halftoning a digitized image, comprising: selecting a cluster screen halftoning system having a cell size of m cluster pixels; selecting a stochastic screen halftoning system size having a set of n stochastic pixels; and merging the set of n pixels and m pixels into a composite stochastic screen of halftone cluster LUT having a set of threshold elements.
Claim 3
Dependent Claim
13 words
The method of claim 1, wherein m is an integer greater than 18.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein m is greater than or equal to 40.
Claim 5
Dependent Claim
16 words
The method of claim 1, wherein n is an integer greater than or equal to 360.
Claim 6
Dependent Claim
139 words
The method of claim 1, wherein a rank order for turning on the elements in at least a first half of the LUT is determined according to the steps of: a) selecting a random pair of elements from all threshold elements within the first half of the LUT; b) swapping the threshold of the two selected random elements; c) calculating a centroid penalty and a momentum penalty associated with the swapped thresholds; d) calculating a centroid penalty and a momentum penalty associated with the thresholds before the thresholds were swapped; e) retaining the swapped thresholds in the first half of the LUT only when a first sum of the step d calculated penalties is less than a second sum of the step e calculated penalties; and f) repeating steps a through e for a predetermined set of i iterations.
Claim 7
Dependent Claim
28 words
The method of claim 5, wherein the second half of the LUT is obtained by taking the inverse of the values of the first half of the LUT.
Claim 8
Dependent Claim
22 words
The method of claim 1, wherein the LUT is used to halftone at least one color separation of a multicolored digitized image.
Claim 9
Dependent Claim
14 words
The method of claim 7, wherein the at least one color separation is yellow.
Claim 10
Dependent Claim
23 words
The method of claim 1, wherein the LUT is selectively used to halftone at least one of a plurality of selected image types.
Claim 11
Dependent Claim
17 words
The method of claim 9, wherein the at least one selected image type is a graphic image.
References Cited (Backward Citations)
US4149194A
Cited
US4485397A
Cited
US4876611A
Cited
US5014123A
Cited
US5181162A
Cited
US5341228A
Cited
EP0665675A2
Cited
EP0665677A2
Cited
EP0665676A2
Cited
US5394252A
Cited
US5673121A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-04-13 | 2001-10-13 | 2002-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-04-13 | 2005-10-13 | 2006-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-04-13 | 2009-10-13 | 2010-04-14 | $7700.00 | Window Closed / Lapsed |