Ever considered using the Danbooru source?
http://danbooru.donmai.us/help/source_code
It'd have a number of useful features like tags, blacklists, image ratings, etc.
It also has a built in duplicate image checker. Recently found out this site doesn't auto check duplicates, so I'm not really in a mood to upload my collection...
Oh and it has a Note overlay feature which is great for translating images without having to edit the image.
sorry danbooru is a too complex to be set up on this site, it's more of a server program then a script you just install.
Right, it's not a script... And neither is SMF.