While there is no public "official" document by this exact name, this file format is commonly associated with:
If you are looking for the specific content within a video you found, it likely belongs to a private archive, a specific workplace internal system, or a local security DVR. 20220606-6_720pmp4
: Refers to the High Definition (HD) resolution, which uses 720 horizontal scan lines (1280 pixels wide). While there is no public "official" document by