KMV is a file extension that is used by an application running on Sansui mobile devices called Mobile DJ. KMV is a file used to store movie clips. It is a multimedia container where data is stored in Matroska format. Various codecs can be used in this format.

KMV files are sometimes not supported by media players. In this case, you can try to change the extension of this file to MKV, which is an alternative and is much more common.