Italian and English are mixed here. If something is in Italian is usually about the country society or something I’ve done here in Italy (like giving a lecture about something in Italian language). Perhaps I’ll make a section for Italian content, but it is not the right time :-)
Scale GIS raster data using gdal_translate
The GIS paladin of raster data, gdal_translate, could solve your headaches when you want to reduce its scale from 16 bit per component to 8 bit per component.