Earlier work showed that maximum entropy models can be used to represent surface reflectance spectra of Munsell patches. Here, we introduce a new approach to color constancy which is based upon that work. To our knowledge, all color constancy approaches employing spectral models use linear basis function representations for surface and illuminant spectra. This means that a set of basis function...

A chromagenic camera takes two pictures of each scene. The first is taken as normal but a specially chosen coloured filter is placed in front of the camera when capturing the second image. The chromagenic filter is chosen so that the combined image makes colour constancy, or white point estimation easier to solve. The chromagenic illuminant estimation algorithm is very simple. We compute the ex...

Only if we can estimate the colour of the prevailing light and discount it from the image can image colour be used as a stable cue for indexing, recognition and tracking (amongst other tasks). Almost all illumination estimation research uses the angle between the RGB of the actual measured illuminant colour and that estimated one as the recovery error. However here we identify a problem with th...

We show how illuminant and reflectance spectra can be accurately measured or separated, up to a multiplicative factor, at each pixel of a scene by using a CCD digital camera instead of a spectroradiometer. In order to obtain suitable spectra of both illuminants and reflectances in a scene, we may use a 6channel measure from the digital 3-channel RGB camera. This is accomplished by taking two im...