Removing artifacts from document images
US9852498B2 · kind B2 · utility
1Cited by
4References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 26, 2016 |
| Grant date | Dec 26, 2017 |
| Priority date | — |
| Expiry date | Apr 30, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V30/40
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Techniques for removing artifacts, such as shadows, from document images are described. A shadow map is generated for a digital image by first determining local background colors using clusters of local pixel intensities. Then, a global reference background color is selected from all pixel intensities of the digital image. Next, a per-pixel scaling factor is determined that maps the local background colors to the global reference background color, which applies localized adjustment to the digital image to remove local shadow.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.