The Playstation 4 could be capable of backwards compatibility for Playstation 1 and Playstation 2 games according to rumours from well placed sources.
The Playstation 4 may be capable of local emulation of PS1 and PS2 titles.
Talking to Eurogamer
, someone working with Sony's recently revealed streaming service Playstation Now revealed that there are no plans to release Playstation 1 and 2 titles over the service, but that these games should run through local emulation on the console.
Further details shared suggest that Sony is pushing for older titles to run without any of the upscaling issues that have been evident in Playstation 3 ports of older games. The quality of backwards compatibility should be comparable to that of unofficial PC emulators for the Playstation 1 and 2.
Sony's history of providing backwards compatibility has been inconsistent. The Playstation 2 was capable of running Playstation 1 games without an issue, but only early versions of the Playstation 3 were able to run Playstation 2 titles.
The decision to discontinue this feature was apparently due to the hardware requiring the equivalent of an entire Playstation 2 to be built into the Playstation 3 unit as the two consoles ran on very different systems.
Playstation Now, a service which Sony intends to bring to not just the Playstation 4 but several other Sony devices including internet-connected Bravia TVs, will stream Playstation 3 titles via an internet connection bypassing the need for hardware compatibility. The service will make use of streaming technology developed by Gaikai, which Sony bought in 2012.