To help you better, could you please clarify where you encountered "dmannemp4"? For example: Is it a on a social platform? Is it a filename for a specific video?
Are you referring to in a video?
A physics engine used in gaming for realistic destruction (e.g., Star Wars: The Force Unleashed ). dmannemp4
A dash camera system that records in MP4 format. To help you better, could you please clarify