Method for compressing images and a format for compressed images
US8600181B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 2009 |
| Grant date | Dec 3, 2013 |
| Priority date | — |
| Expiry date | Feb 22, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/60
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
There is provided a method for compressing images and an image format. The method comprises performing a transform on pixel portions of image data and evaluating resulting coefficients from each transform in terms of a flatness condition. If the transform is found to be flat then the result from the transform is quantized according to a first quantizing scheme. If the transform is found not to be flat then the result from the transform is quantized according to a second quantizing scheme being different from the first quantizing scheme. Different block arranging schemes are proposed for the quantizing schemes. An indicator is stored in the block indicating that the image block is flat or not flat. The resulting bits are written into a compression data structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.