Method and apparatus for processing image files
US6381371B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1999 |
| Grant date | Apr 30, 2002 |
| Priority date | — |
| Expiry date | Mar 17, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T3/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for manipulating digitized images stored as variable length encoded bitstreams such as JPEG format in a manner that reduces memory and processor resource requirements. A prescan means sequentially decompresses the bitstream to identify the location of encoded pixel image areas. Designated ones of these locations are recorded or stored in a prescan table. After the prescan operation has been performed on the image, image manipulations such as rotating, cropping, and zooming can be performed on a selected portion of the image by directly accessing only the encoded pixel image areas to be manipulated, without the need to sequentially decode and store all the encoded image areas in order to locate the ones of interest.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.