Automatic white balance method and apparatus

Details Automatic white balance method and apparatus Automatic white balance method and apparatus

2005-01-25

2010-06-01

Chan, Jason (Department: 2622)

Television

Camera, system and detail

Combined image signal generator and general image signal...

C348S222100, C348S225100, C348S227100, C348S254000, C348S255000, C358S516000, C358S518000, C358S520000, C358S509000, C382S162000, C382S163000, C382S167000

Reexamination Certificate

active

07728880

ABSTRACT:
Automatic white balance of captured images can be performed based on a gray world assumption. Initially, a flat field gray image is captured for one or more reference illuminations. The statistics of the captured gray image are determined and stored for each reference illumination during a calibration process. For each subsequent captured image, the image is filtered to determine a subset of gray pixels. The gray pixels are further divided into a one or more gray clusters. The average weight of the one or more gray clusters is determined and a distance from the average weights to the reference illuminants is determined. An estimate of the illuminant is determined depending on the distances. White balance gains are applied to the image based on the estimated illuminant.

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