Electronic image compression method and apparatus using interlocking digitate geometric sub-areas to improve the quality of reconstructed images
US5093872A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 2, 1989 |
| Grant date | Mar 3, 1992 |
| Priority date | — |
| Expiry date | May 2, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/00
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for compressing digital image data using interlocking digitate geometric sub-areas. The digital picture elements, or PELs, representing the image are divided into interlocking digitate sub-areas, which, in the preferred embodiment, are of substantially the same size and shape. Data compression is achieved for the PELs within a sub-area by first sorting the values of the PELs within the sub-area by magnitude. Depending upon the magnitudes of the PELs in the sub-area relative to the magnitudes of the other PELs in the sub-area, the PELs in the sub-area are either coded solid tone, with each PEL in the sub-area having the same tone, or coded bi-tonal, with each PEL in the sub-area having either one of two tones. A smoothing process is utilized to reduce undesireable effects at the edges of the sub-area.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.