install opencv via opkg

Hi im using a BB xM running Angstrom demo image.

I'm trying to install OpenCV for my BB but everytime i type
"opkg install opencv" i gives me this:

btw i need OpenCV 2.1 particularly and Python Interface too.
collected errors:
+ opkg_conf_init: could not create lock file /usr/lib/opkg/lock:
Permission denied.

I also need some basic command to run around Angstrom coz everything I
know from using Ubuntu doesnt work here.

I know I'm asking the same old question about openCV but plz, im a
newbie and I really to get thing works out on my BB.

Are you root when doing that? if not, do a 'su -' before trying to install packages