@alvin Judging from scraped videos, they are 720x480 and 30 FPS with H.264 encoding (I assume legacy), and AVC1 (MPGA) for audio. Scraped videos in this format play on the OGST TFT screen during game selection.
I looked at the Wiki article mentioned in my earlier question about how I customize and override the videos shown during system selection, and the only mention of videos on that wiki page was bootvideos, so this is what I have been attempting.
Nowhere does a search for "system videos" match content in the wiki as it stands.
Therefore my original question remains: How may I add to the videos shown when navigating to one system and the next? The faux FBI warning shown for certain consoles/computers is just tiring...