Ello ,
I might have a solution for you.
goto http://www.amazemail.com/ and get phpMyPhilter. Once you get that running you can the add/edit the current badwords with your [IMG 1], [IMG 2] etc
I know its for bad words but atm Im using it to replace bad words and smilies with a picture and works great.
in the lib/badwords_en file you`ll see...
array("🙂"," <img src=smilies/smile1.gif width=15 height=15> "),
you could always replace this with your
array("[IMG 1]","<img src="{image returned from database}">"),
That way you can live edit the posts and display the image without changing your post text.
$newmessage = $row_MyMessages['message'];
$any = messagefilter($newmessage,1);
echo ($newmessage);
If this isnt what you want im sure someone will post an alternative idea 🙂