Method and sensor for determining the local contrast of an observed scene by detection of the luminance from said scene
US7170043B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 2003 |
| Grant date | Jan 30, 2007 |
| Priority date | — |
| Expiry date | Sep 4, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/708
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention relates to a method of calculating the local contrast at each pixel (PC) in a network (Mp) of photosensitive pixels which are arranged in at least one dimension (x, y). The inventive method consists in, during successive image acquisition cycles, producing a signal which is representative of the local luminance at each pixel, said luminance-representative signals being integrated values of luminance values sensed by the respective pixels (pC, pG, pD, pH, pB). The inventive method consists in: sampling the integrated values of the signals representing the luminance values at the pixels adjacent (pG, pD, pH, pB) to a considered pixel (pC), said sampling taking place at an instant in the cycle when the integrated value of the luminance at the considered pixel (pC) is equal to a pre-determined reference value; and determining the local contrast at the considered pixel (pC) on the basis of values thus sampled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.