The replacement can be confined to a box.
The clipped data overwrites the file specified on the command line unless the outfile option is used
clip lyr max=2000
-
replaces all pixels in the file lyr with values greater
than 2000 with 2000.
clip ring min=sky-100 vmin=0
-replaces all pixels in the
file ring that are more than 100 adus below the sky value with
zero.