My WID is not a number. What to do? Can I change it to a number?

[BuddhiLW]

System info:
arcolinux, with xmonad

Steps to reproduce:

xwinwrap -ov -fdt -fs -ni -b -nf -un -o 1.0 -debug -- mplayer -wid WID --loop --no-audio animation.gif

xwinwrap: desktop window (94a) is root window
xwinwrap: window type - override
The wid option must be an integer: WID
Error parsing option on the command line: -wid
MPlayer SVN-r38407 (C) 2000-2022 MPlayer Team
226 audio & 469 video codecs
mplayer died, exit status 1