OpenCV

I know the question has been asked, but i would like to know, how would i install OpenCV or similar to the YUN/Dragino YUN Shield?

I want to do occasional face detection / GLYPH recognition. Not constant or even realtime, just when triggered

Or Suggestions of alternatives would be great

Wait for OS update?

http://forum.arduino.cc/index.php?topic=318309.msg2223098#msg2223098