Method for approximating a value which is a nonlinear function of the linear average of pixel data
US4910694A · kind A · utility
Inventor
Key dates
| Filing date | Jan 11, 1988 |
| Grant date | Mar 20, 1990 |
| Priority date | — |
| Expiry date | Jan 11, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/843
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system for weighting nonlinear, e.g. logarithmic, pixel data as part of a missing pixel interpolation. This is accomplished to generate a weighted average of the logarithmic intensity values for those pixels which surround the missing pixel in order to approximate the logarithm of the linear average of these pixel values. Two weighting coefficients of unequal value are selected so that their sum equals the quantity one. The larger of the logarithmic values is weighted by multiplying the larger logarithmic pixel value by the larger weighting coefficient, and then by adding to this quantity the smaller logarithmic pixel value which has been multiplied by the smaller weighting coefficient. The result is a weighted logarithmic average which approximates the log of the linear average.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.