G4_0139.mp4 -

: GoPro often uses a naming convention like GH010139.mp4 or GX010139.mp4 . If your file is g4_0139 , it may be a renamed clip or from a specific mobile app export.

: Likely a low-resolution proxy or a very short "event" clip from a dashcam. g4_0139.mp4

To help you review the content, here are common ways to identify what that specific file might be: Common Sources for "G4" Filenames : GoPro often uses a naming convention like GH010139

: Right-click the file and select Properties (Windows) or Get Info (Mac). Look at the "Origin" or "Camera" section to see what device created it. g4_0139.mp4