Remote Play works by downscaling the 1080p framebuffer to the Vita's native 960x544 resolution, using the PS4's in-built hardware h.264 video encoder to compress the image. This is then beamed out over WiFi to the Vita, which decodes the video and sends back controller inputs to the PlayStation 4. It's effectively OnLive cloud streaming technology relocated to the home - the difference being that image quality issues can be resolved through much higher-bandwidth video, while input latency is cut down considerably owing to the localised nature of the network.
Remote Play itself is nothing new of course - PSP and Vita had lacklustre, laggy support for a handful of PS3 games - but Vita itself has seen virtually no additional support, despite the introduction of a higher-quality 480p protocol. Indeed, those running hacked PS3 firmwares have had access to the most games. The problem is that PS3 Remote Play is based around software video encoding via the Cell's SPUs, and developers are not keen on sacrificing that CPU time for Remote Play support, while the technology itself is slow to respond, with dodgy image quality.
It's all change for PlayStation 4, which features bespoke hardware video encoding for Remote Play, gameplay recording and screen-sharing support with all the benefits of the Gaikai streaming technology.It's a feature built into the operating system itself, incurring no performance penalty to developers.Up until now, the question has been to what extent publishers would want the feature enabled - conceivably, opening up a new library of software for Vita could steal sales from games designed for the system. The news that Sony is mandating support for all titles that don't require the camera takes the choice away from the publishers and ensures a level of consistency in the features that the majority of games offer.
