Method and apparatus for automatic image calibration for an optical scanner
US6188801A · kind A · utility
Inventors
Key dates
| Filing date | Aug 31, 1998 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Aug 31, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/98
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A memory is divided into several blocks in advance for storing calibrated pixels in sequence. Then, start to check each pixel row by row. The obliquity ratio of each pixel will be computed based on two referential blocks on the two sides of the calibration paper. The obliquity ratio will then divided by the length of one pixel. If the residue of the division is larger than half the length of the pixel, it indicates that that pixel is the beginning of next block. Following this rule, we can divide each row into several blocks. The skew pixels will be calibrated according to a first calibration procedure and a second calibration procedure. The calibrated pixels will be stored in the memory blocks in sequence according to their block numbers. After all the pixels of the same row have been calibrated, the calibrated pixels will be read from the memory blocks in sequence. The calibrated procedure repeats until each row of the image has been calibrated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.