Prevent Download or Access Priviledges, Except for Viewing Purpose

I have 5 websites, for which there is either an images or pictures folder in each one. - I would like to deny access priviledges to the graphics or images and swf files in the folder. When users try to download such files in the folder individually , they should see the page that says they are not authorized to access or view. - Prevent download priviledges to graphics or swf files in the folder, ie. prevent audience from being able to effectively download graphics or images and swf files from the folder. (.htaccess permissions definitely need to be set. But understand this is NOT the only thing to set or control.) The only place that allows these graphics or images and swf files to be displayed should be only the html documents in the public_html folder. Lastly, - Prevent Image Hotlinking. That is, I would like to prevent others from Hotlinking to graphics or images in the folder, so that webmasters from other sites cannot display my graphics or images and swf files on their websites. So, for 5 websites, one folder ONLY in each website that stores all the graphics and swf files, for your work's convenience.