Methods and systems for camera characterization in terms of response function, color, and vignetting under non-uniform illumination
US10504239B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 2016 |
| Grant date | Dec 10, 2019 |
| Priority date | — |
| Expiry date | Aug 3, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30244
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Methods and systems for describing a camera radiometrically, in terms of camera response function and vignetting, and in terms of color, suitable for non-uniform illumination set-ups. It estimates the camera response function and the camera color mapping from a single image of a generic scene with two albedos. With a second same-pose image with a different intensity of the near-light the vignetting is also estimated. The camera response function calibration involves the segmentation of the two albedos, the definition of the system of equations based on the assumption that can be made about the image formation process, and the actual estimation. For the modelling the vignetting there are three steps: computing the albedo-normalized irradiance, finding points of equal vignetting, when needed, and estimation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.