What about PS1 and PS2 games?
There is some good news, though. Sony is reportedly working on native emulation for PS1 and PS2 games in the PS4. This means you won’t need to use PlayStation Now to play your very old games, and will be able to simply put the disc in your PS4. This rumour comes from Ashan Rasheed, an ‘industry insider’. However, it is certainly nothing more than a rumour at this point. Rasheed says that the PS4 will be able to run older games at 1080p resolution too, rather than the much lower native resolutions of the older consoles – most PS1 games are designed to run at 240 x 320 resolution. This won’t mean 20-year-old will suddenly look fresh, but it will reduce the ‘jagginess’ in polygons in these older games.
got this from here