lpr saturation not working (CUPS) -

it's simple question, want know why command not working me.

i'm using on terminal this:

lpr -o saturation=0 namefile.png

this should print in black & white printing in color. maybe need install , don't know, can't find solution.

someone knows should do? thank you!

it may if try

lp -o saturation=0 namefile.png

or

lp -d name-printer -o saturation=0 namefile.png