Image compression system using halftoning and inverse halftoning to produce base and difference layers while minimizing mean square errors
US6141450A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 1998 |
| Grant date | Oct 31, 2000 |
| Priority date | — |
| Expiry date | Feb 10, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T9/004
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A two-layer image compression device is disclosed with a halftone circuit, an inverse halftone circuit and a quantization circuit. In this circuit, the halftone circuit converts the input gray-scale image into a binary image and rearranges the binary image output sequence to serve as a base layer of the input gray-scale image. The inverse halftone circuit recovers a predicted image from the binary image using the LMS algorithm and multi-table look-up methods. The quantization circuit then compares the input gray-scale image with the predicted image and encodes the difference between them to obtain an enhancement layer of the input gray-scale image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.