USGS- science for a changing world (2001) 9 pages
Regional Landsat applications often rely on clear and near cloud-free images. With the spectral value being represented by digital number (DN), however, such images contain substantial noises. A significant proportion of such noises can be normalized by converting the DN to at-satellite reflectance value. Being physically based and ready to automate, the conversion method can serve as a first order normalization of Landsat 7 images, making it possible to derive land surface information from such images more consistently.
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