Method of reducing digital images
US4931881A · kind A · utility
17Cited by
6References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 1, 1989 |
| Grant date | Jun 5, 1990 |
| Priority date | — |
| Expiry date | May 1, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V30/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image binarization system in which the threshold value used for the binarization process can be adjusted to thereby enable the process to be made more accurate and avoid loss of black areas in characters in the process of digitizing and conversion. The threshold value is based on the average value of pixel density values around the pixels to be binarized, and is corrected downward when the average density value of the surrounding pixels is larger than a specific boundary value, and upward when the average value is smaller than the said boundary value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.