Electronic retrieval of information from form documents
US5694494A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1996 |
| Grant date | Dec 2, 1997 |
| Priority date | — |
| Expiry date | Sep 13, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V30/10
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for retrieving user-supplied information from a scanned version of a completed document is described. The method includes the steps of obtaining a first image of the document having information printed thereon in its blank format before other information has been added to it by the user. A second image of the document is obtained after information has been added to it by the user. The two images are aligned, and for each pixel in the first image which corresponds to information on the document, those pixels are deleted from the second image to create an image which corresponds to subtraction of the first image from the second image. Finally, a step is performed to electronically restore the information added by the user which was deleted during the subtraction operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.