A few Digital Foundry readers have pointed out that the PS4 version of Final Fantasy 14 features an interesting option in the display settings menu that allows you to select between two different rendering modes, labelled 'Full HD Quality' and 'HD Quality'. We're sorry we missed this in the Final Fantasy 14 face-off we published at the weekend, but we've been looking into it over the last few days and it throws up some interesting results.
Pixel counting reveals that the 'HD Quality' setting gives us an artificially edge-enhanced 720p presentation which is actually derived from a native 1080p image. Essentially, the game renders internally at 1080p before the framebuffer is downscaled to 720p, a sharpening filter is applied and it's all rescaled back to 1080p before being displayed. Anti-aliasing, art assets and all the effects work remain unchanged from the default 'Full HD Quality' mode, although image quality takes a hit due to the framebuffer being rescaled twice: long edges appear visibly more uneven, while the finest details appear smoothed over in comparison to normal 1080p.
More damagingly, the use of edge-enhancement introduces visible halos around a few objects in bright scenes. The effect also generates an illusion of sharpness around texture details that helps to slightly lessen impact of the blur, but it does so in a way which makes things appear fuzzy and artificial, so overall it feels unwelcome.
Initially it's hard to decipher why it's there at all, because as you'll see further down the page there's no obvious boost to frame-rate, but we think we've figured it out. By forcing the PS4 to display in 720p, the edge filter goes away, giving us a cleaner, naturally sharper image by letting the HDTV handle the final upscale from 720p to 1080p. Presumably, then, this 'HD Quality' option is for people with 1366x768 TVs and others restricted to 720p.
As for the edge filter, it is remarkably similar to the effect Microsoft's 'enhanced' scaling on Xbox One introduces in other games, leading us to suspect it's a built-in feature of the similar AMD GPUs that both next-gen consoles use rather than something cooked up by Sony, Microsoft or Square Enix. That would also support the suggestion that the 'HD Quality' mode is for people with 720p TVs, because the edge filter seen when the 'HD Quality' image is upscaled to 1080p also comes into effect on games being downscaled by the hardware, such as Assassin's Creed 4 running on a 720p TV. With the 'HD Quality' option enabled in Final Fantasy 14, people with 720p TVs ensure the game is handling that downscale rather than the hardware.
In theory, having the game render natively in 720p should translate into higher frame-rates in most instances, but because the 'HD Quality' mode is about elegantly handling a downscale for Final Fantasy 14 with 720p TVs, it always operates at 1080p internally and so you don't see any frame-rate improvements after all. As you can see in the video below, frame-rates appear near-identical in like-for-like scenes. What might have been a nice way of trading image quality for smoothness turns out to be much less exciting, then, albeit useful for a subset of players. Anyone playing at 1080p, though, will certainly want to stick with 'Full HD Quality'.