Open IBT File
An IBT extension file, contains textures and models used by the video game 'Thief: Deadly Shadows', also known as 'Thief 3'.
About the game Thief: Deadly Shadows
Thief: Deadly Shadows is a video game developed by Ion Storm for Microsoft Windows and Xbox that was released in 2004. It is the third video game in the Thief series. : Deadly Shadows, the player takes on the role of Garrett, a master thief.
Thief: Deadly Shadows was developed by Ion Storm using the Unreal engine, and was later published by Eidos.
The IBT file is a system file and is installed along with other Thief 3 game files and is required for the game to work.
The IBT file is a proprietary file and therefore you should not try to open it manually with software other than the one that created it.