Recovering parameters from a sub-optimal image
US8009880B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 2007 |
| Grant date | Aug 30, 2011 |
| Priority date | — |
| Expiry date | Jun 22, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30201
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A subregion-based image parameter recovery system and method for recovering image parameters from a single image containing a face taken under sub-optimal illumination conditions. The recovered image parameters (including albedo, illumination, and face geometry) can be used to generate face images under a new lighting environment. The method includes dividing the face in the image into numerous smaller regions, generating an albedo morphable model for each region, and using a Markov Random Fields (MRF)-based framework to model the spatial dependence between neighboring regions. Different types of regions are defined, including saturated, shadow, regular, and occluded regions. Each pixel in the image is classified and assigned to a region based on intensity, and then weighted based on its classification. The method decouples the texture from the geometry and illumination models, and then generates an objective function that is iteratively solved using an energy minimization technique to recover the image parameters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.