Methods and apparatus for enhancing gray scale images
US5604545A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1994 |
| Grant date | Feb 18, 1997 |
| Priority date | — |
| Expiry date | Jul 8, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/20221
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image enhancement system that efficiently enhances gray scale images, wherein an analog scene is captured and a resulting analog signal is digitized to a raw gray scale image S. Image S is divided into M disjoint non-empty regions R.sub.1 . . . R.sub.M, where S.sub.i identifies region R.sub.i of S. The raw digitized signal S.sub.i is processed in accordance with an enhancement algorithm to obtain a set of enhancement parameters (offsets P.sub.i =(s.sub.ai, s.sub.bi) and weights (w.sub.i)). Digital offsets P.sub.i =(s.sub.ai, s.sub.bi) are converted to analog offsets Q.sub.i =(v.sub.ai, v.sub.bi). The analog signal is stretched and clipped and converted to a digital signal that is an enhanced image signal T.sub.i. The enhanced image signal is multiplied by weight w.sub.i to obtain the final enhanced image U.sub.i. Image U.sub.i forms the region R.sub.i of a final enhanced image U. The multiplied signals are summed to produce an enhanced summed image of the scene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.