not used on ixus160.
Sorry about that, I was assuming it does work. I'd still recommend you to continue investigating. For example, the ixus140 port could be a good candidate: it's a relatively recent camera and the viewport related addresses should be correct there.
You'll find that finding the equivalent of the ixus140 addresses will end up with the same ones I already posted. If you're sure they don't work, you'll need to do original research
on the camera. Most people doing ports get away without doing that, but Canon's code changes make it necessary from time to time.