: 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.
To help you review the content, here are common ways to identify what that specific file might be: Common Sources for "G4" Filenames g4_0139.mp4
: Certain DJI or Autel flight logs or cached video previews occasionally use similar alphanumeric strings. How to Review the File : GoPro often uses a naming convention like GH010139
: Likely high-definition footage from an action camera or drone. g4_0139.mp4
: 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.