Empirically derived NDVI products have been shown to be unstable, varying with soil colour, soil moisture, and saturation effects from high density vegetation.
In an attempt to improve NDVI, Huete[1] developed a vegetation index that accounted for the differential red and near-infrared extinction through the vegetation canopy.
The index is a transformation technique that minimizes soil brightness influences from spectral vegetation indices involving red and near-infrared (NIR) wavelengths.
The transformation was found to nearly eliminate soil-induced variations in vegetation indices.
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