: Check the "Camera Model" field in the file's extended properties to identify which device captured the footage. Default File Name - GoPro Support

: Software like Adobe Premiere Pro often creates "proxy" files (lower-resolution versions of raw footage) with simplified names for easier editing.

If you have found this file on a hard drive or SD card and want to see what it is:

: GoPro cameras use specific naming conventions like GHxxxxxx.mp4 (H.264) or GXxxxxxx.mp4 (HEVC). A file named g_147.mp4 suggests a custom or legacy camera setting where "g" stands for the device and "147" is the sequential clip number.

: If your default player won't open it, use the VLC Media Player . It can play almost any MP4 file, even those with missing headers or unusual codecs.

: Many digital video recorders (DVRs) save clips using a single letter and a sequence number (e.g., G for "Gate" or "Group") to organize surveillance logs. How to Review the Content Yourself