With little fanfare, Sony last month confirmed the arrival of PlayStation 2 emulation on the PlayStation 4. But it was extremely light on the details of just how the feature might work.

We still don't know for sure what Sony is planning, but a recent video from the company—which was quickly pulled—shared a few extra details on backwards compatibility.

In the video, Sony showed off someone playing the older Dark Cloud game for the PlayStation 2 on a Playstation 4. The video itself wasn't that illuminating, but Sony's description revealed just how the PlayStation 2 emulation feature may (or may not) work.

"Experience Dark Cloud with 1080p up-rendering and Trophies. Additional enhanced features include Shareplay (Active PS Plus membership may be required), Remote Play, Activity Feeds, and Second Screen support for game manuals through the PS Vita system or PlayStation App," read the description, as reported by Gematsu.

"Copyright 2011 Sony Computer Entertainment Inc. Dark Cloud is a trademark of Sony Computer Entertainment Inc. PS2 Classics and PS2-formatted discs are incompatible with the PS4 system."

In other words, you aren't going to be able to just stuff an old PS2 game into your PS4 and expect it to play, which is different than how Sony rival Microsoft is handling backwards compatibility between the Xbox 360 and the Xbox One. In that setup, you do need to have your older disc inserted into your Xbox One in order to play it. The console notices the disc and fires up a software emulator of an Xbox 360, which then plays the title.

So, we're not quite sure how Sony's backwards compatibility might work at this point. However, Sony is likely going to talk a lot about the feature at this year's PlayStation Experience, which kicks off tomorrow in San Francisco. Perhaps Sony's quick removal of the video indicates that it might be changing up how backwards compatibility works after all.