The filename indicates it is likely a video file recorded by a DVR or NVR security system (often associated with brands like Hikvision or Dahua ). Meaning of the Filename Parts:
: A Unix Timestamp . This number represents the exact second the video was recorded. Converted Time: Saturday, July 21, 2018, 08:28:50 AM (UTC) . Key "Feature" 38499-70 701531471561_Sub_f_1532161730.mp4
: Lower resolution, designed for remote viewing on mobile devices or multi-screen grids to save bandwidth. The filename indicates it is likely a video