Method and device for detecting and correcting skewed image data
US8358871B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 2009 |
| Grant date | Jan 22, 2013 |
| Priority date | — |
| Expiry date | Sep 23, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/20068
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A skewed image data detecting and correcting device includes a skew angle detecting module, and an image rotating correction module. A skewed image data detecting and correcting method includes the following steps. Firstly, a binary digitizing operation is performed to obtain a binary image data. The binary image data is rotated by multiple different rotating angles, thereby obtaining multiple rotated binary image data. The pixel numbers of all horizontal rows of the rotated binary image data are totalized, thereby obtaining multiple horizontal pixel number distribution curves. A high-pass filtering procedure is performed to filter off low-frequency noise, thereby obtaining multiple high-frequency signal curves. The square sums of respective high-frequency signal curves are calculated, thereby obtaining multiple index values. Afterward, a rotating correction operation is performed on the image data according to the rotating angle corresponding to a maximum of the index values, thereby obtaining a corrected image data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.