Scene adaptive brightness/contrast enhancement
US9055227B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 2011 |
| Grant date | Jun 9, 2015 |
| Priority date | — |
| Expiry date | Nov 1, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/20081
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for brightness and contrast enhancement includes computing a luminance histogram of a digital image, computing first distances from the luminance histogram to a plurality of predetermined luminance histograms, estimating first control point values for a global tone mapping curve from predetermined control point values corresponding to a subset of the predetermined luminance histograms selected based on the computed first distances, and interpolating the estimated control point values to determine the global tone mapping curve. The method may also include dividing the digital image into a plurality of image blocks, and enhancing each pixel in the digital image by computing second distances from a pixel in an image block to the centers of neighboring image blocks, and computing an enhanced pixel value based on the computed second distances, predetermined control point values corresponding to the neighboring image blocks, and the global tone mapping curve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.