Image rotation method
US4689824A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 1983 |
| Grant date | Aug 25, 1987 |
| Priority date | — |
| Expiry date | Dec 30, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T3/606
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for rotation of a binary image by 180 degrees, includes the steps of: positioning first and second address pointers at the center of at the beginning and end respectively of an image to be rotated; indexing the first pointer in a first direction through said image; indexing the second pointer in a second direction through said image; exchanging, for each index step, a first image word at the first pointer with a second image word, at the second pointer if the first image word and the second image word have any two bits with different values; reversing all exchanged words; storing the reversed, exchanged words at said pointer locations; repeating the above steps until the first pointer and the second pointer have been indexed through all words in the image at which point the image has been rotated by 180 degrees.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.