Method for reconstructing a bi-level image from a low quality discrete transform image
US6434273B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2000 |
| Grant date | Aug 13, 2002 |
| Priority date | — |
| Expiry date | Jun 28, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T9/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The image reconstruction method generates higher quality reconstructed images from compression of a bi-level image. The method includes thresholding to force pixels of the starting image to be closer to bi-level to generate a threshold image. The method transforms the threshold image to generate transform coefficients representing the decomposition of the threshold image. The method selectively clamps the transform coefficients into quantization bins defined by compression of the bi-level image. The selective clamping generates modified coefficients corresponding to the higher quality reconstructed image. The method also includes applying an inverse-transform on the modified coefficients to generate higher quality reconstructed image. The starting image and the reconstructed image can be compared to determine the degree of improvement obtained with the method. The method can be repeated iteratively to obtain an image that more closely represents the original image than does the original lower-quality image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.