Check if image referer is my site, if not redirect it to another page

hi,
i have a certain image that gets tonnes of hits, however most are viewed straight as the image (ie not embedded in any page). how can i (with htaccess) check if its referer is from mysite.com, and if it isn't redirect it to mysite.com/viewtheimage.html?

thanks

 

This might help you: http://altlab.com/htaccess_tutorial.html (Sorry can't post clickable urls yet)