Patent · US Active

Digital image exposure correction

US7826660B2 · kind B2 · utility

4Cited by
178References
27Claims
0Family size

Inventors

Key dates

Filing dateOct 12, 2006
Grant dateNov 2, 2010
Priority date
Expiry dateJul 30, 2027

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/4072
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Techniques are disclosed for correcting the exposure of a digital image. An exposure predictor may be generated based on a set of images for which ground truth data are known. After identifying an optimal set of features, the exposure of the digital image may be corrected by extracting values of the selected optimal features from the image, using the predictor to predict a desired exposure correction for the image, and correcting the exposure of the image by the predicted desired amount. Exposure correction is based on a model that relates intensity of light in the world to the RGB digits of the digital image. The model comprises a gamma function that models the response of a typical monitor and a S-shaped curve that compresses the large dynamic range of the world to the small dynamic range of the RGB digit space.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.