Installing qrtools gem

I am trying to build an application to decode and encode qr code.
qrtools seemed to be the best gem for my requirements.

However when I tried to isntall it I ran into errors. did the most
logical thing by copying the error and googling… coulndt get much help
from that…

the error suggest that I need qrencode

I searched for it on google and got

I found the windows version of qrencode
http://code.google.com/p/qrencode-win32/

where I got these links
http://code.google.com/p/qrencode-win32/downloads/list

but these r just source codes how do I use them for my ruby to
regocnise…
I tried updating the enviornment variables… did not work
I am using windows 7.