US5020122A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic document image revision
Assignee: Pitney Bowes Docsense Inc
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Filing: 1989-03-10
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Granted: 1991-05-28
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Expires: 2009-03-10
Abstract
Abstract A system for electronically storing revisions or modifications to documents which are already electronically stored in unrevised or unmodified form. The system compares, at the pixel-by-pixel level, a modified document bit map with a stored document bit map and determines from the differences between the two bit maps, at the pixel-by-pixel level, which differences are significant and which are insignificant. A revised document bit map is then formed from the portions of the stored-document bit map exhibiting no significant bit map differences and the significant differences bit map. The result is a revised document bit map in which no unnecessary changes have been introduced into the initial stored-document bit map. The system also includes steps for defining, on a pixel-by-pixel basis, a significant region bit map from the significant difference bit map and for forming the revised document bit map using the significant region bit map.
Inventors
- 👤 John M. Walsh
- 👤 David M. Ott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:53
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/40093
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
158 words
In a system for electronically capturing and storing images of documents in which stored documents are represented by bit maps identifying black and white pixels of the images, a method of storing entries made on a predetermined standard form document, said standard form document having a representative standard form bit map already stored in the system, comprising the steps of: forming a binary modified-form bit map representing a modification of said binary stored-form bit map, said modification comprising said entries on said form; comparing, pixel-by-pixel, said modified-form bit map with the stored-form bit map to determine the differences between said stored-form bit map and said modified-form bit map; determining, pixel-by-pixel, which of said differences are significant and which are insignificant; forming a significant-difference bit map representing significant differences between said stored-form bit map and said modified-form bit map; and storing said significant-difference bit map in memory, whereby said entries are stored in memory separately from said predetermined form.
Claim 2
Dependent Claim
158 words
In a system for electronically capturing and storing images of documents in which stored documents are represented by bit maps identifying black and white pixels of the images, a method of storing entries made on a predetermined standard form document, said standard form document having a representative standard form bit map already stored in the system, comprising the steps of: forming a binary modified-form bit map representing a modification of said binary stored-form bit map, said modification comprising said entries on said form; comparing, pixel-by-pixel, said modified-form bit map with the stored-form bit map to determine the differences between said stored-form bit map and said modified-form bit map; determining, pixel-by-pixel, which of said differences are significant and which are insignificant; forming a significant-difference bit map representing significant differences between said stored-form bit map and said modified-form bit map; and storing said significant-difference bit map in memory, whereby said entries are stored in memory separately from said predetermined form.
Claim 3
Dependent Claim
63 words
The method of claim 1, further comprising the step of: forming an additions bit map and a deletions bit map for recording said differences between said stored-form and modified-form bit maps, said additions and deletions bit maps identifying pixels in said modified-form bit map which have changed, respectively, from white to black and from black to white compared with said stored-form bit map.
Claim 4
Dependent Claim
38 words
The method of claim 2, further comprising the step of: identifying as insignificant the pixels of said additions and deletions bit maps which are connected within a predetermined range to like colored pixels of said stored-form bit map.
Claim 5
Dependent Claim
52 words
The method of claim 2, further comprising the steps of: deleting said insignificant pixels from said additions and deletions bit maps to form stripped-additions and stripped-deletions bit maps; and selectively causing said stripped-additions and stripped-deletions bit maps to grow so as to contact like colored pixels of said initial stored-form bit map.
Claim 6
Dependent Claim
23 words
The method of claim 2, further comprising the step of: selectively causing said significant-difference bit-map to grow to define a change-region bit map.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-05-27 | 1994-11-26 | 1995-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-27 | 1998-11-26 | 1999-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-27 | 2002-11-26 | 2003-05-28 | $7700.00 | Window Closed / Lapsed |