The authors describe a novel, indirect method for estimating thecorrelated color temperature of illuminants by using a color videocamera and a set of several known color chips. The video camera can havearbitrary shooting chromaticity characteristics; however, it should beused in fixed white balance. The correlated color temperature of thelight source illuminating the color chips is estimated. Using the methodof least squares, an accuracy from 0.1% to 1.4% is achieved, dependingon the spectral distribution of the illuminants. The method fullyutilizes microcomputer capabilities in acquiring the camera outputs,solving a set of simultaneous linear equations, and searching for thenearest (U, ν) coordinate values on the black-body locus
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