  File type identification and file type clustering may be difficult tasks that
have an increasingly importance in the field of computer and network security.
Classical methods of file type detection including considering file extensions
and magic bytes can be easily spoofed. Content-based file type detection is a
newer way that is taken into account recently. In this paper, a new
content-based method for the purpose of file type detection and file type
clustering is proposed that is based on the PCA and neural networks. The
proposed method has a good accuracy and is fast enough.
