Note: help and version output are generated by a naïve script which tries a few variants of
<command> --help, <command> -h etc. to find the command's help and version info.
Sometimes it gets lucky, sometimes it doesn't; if the output below looks wrong, it probably is.
gamma4scanimage -V (return code: 255)
gamma4scanimage error: gamma=0.000000 out of range [0.1;5]
gamma4scanimage (return code: 255)
Usage: gamma4scanimage gamma [shadow [highlight [maxin [maxout]]]]