Document image scanner with variable resolution windows
US5293432A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 1992 |
| Grant date | Mar 8, 1994 |
| Priority date | — |
| Expiry date | Jun 30, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T3/403
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A document image scanner for reading a scanned document multiple times at resolutions different from the scanned resolution without rescanning. A sensor scans the source document to generate a digitized image that is stored in a memory at a first resolution. An input shifter is coupled to the memory for receiving a first number of pixels per line of the digitized image from memory. A vertical scaling element is coupled to the memory for changing a first vertical resolution to a second vertical resolution as the digitized image is transferred to the input shifter from memory. An output shifter is coupled to the input shifter for receiving a second number of pixels per line of the digitized image from the input shifter, wherein the ratio of the second number to the first number is the scaling factor. A horizontal scaling element is coupled to the memory for changing a first horizontal resolution to a second horizontal resolution as the digitized image is transferred to the output shifter from the input shifter. The horizontal scaling element causes the output shifter to receive the second number of pixels per line. An edge retention element is coupled to the horizontal and/or vertica…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.