Can somone just tell me where I can find this code

[Colin F]

the whole file bbcodeparse.php is used to parse the bbcode.

actually checking the forumpermissions is done in another file (fetchforumpermissions() or something), but the parsing is done in bbcodeparse.php. And IIRC you want to add [img] tag per usergroup, so you would probably have to add the code in the bbcodeparse.php file.