What are the lower and upper DN values for European products?
For European products (CEOS, FAST, GeoTIFF, formats), the lower DN value is 0 and the upper DN value is 255. An image pixel value set to 0 has a radiance value equal to the lower radiance limit (Lmin) and an image pixel value set to 255 has a radiance value equal to the upper radiance limit ((Lmax). In the case of Landsat, misunderstandings can occur during the computation of gain value because other (non-European) processing systems use the 0 image pixel value to flag background pixels. In this scenario, is therefore equal to 254 rather than 255. Furthermore, Some misunderstandings can arise due to information provided by the format. The CEOS format does not provide the lower and upper DN values, because these never change (0,255). However the radiometric ancillary record of the leader file informs on the gain, the offset and the lower and upper spectral radiances of every band. Through the metadata file, The FAST and GeoTIFF formats provide lower and upper DN values which are NOT 0 a
