Scan image processing
US5282053A · kind A · utility
22Cited by
6References
14Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 23, 1991 |
| Grant date | Jan 25, 1994 |
| Priority date | — |
| Expiry date | Oct 23, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/401
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The method of scanning a document by providing a test patch to be scanned, initially scanning the test patch and storing the signal response of each reading element to the test patch in a pixel threshold table, providing a document to be scanned, scanning the document and comparing the signal response of each reading element with the corresponding signal response in the pixel threshold table, and printing a mark or not printing a mark in response to the comparison for each reading element. The method includes an extended threshold table to cover halftone cells.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.