Simon Cooke, a software engineer working for Microsoft in its Xbox Advanced Technology Group department, has recently explained why he believes 30fps isn’t enough for gaming.
As most gamers know, there is a constant back-and-forth battle between both console and PC gamers over whether 30 or 60fps is acceptable/optimal (respectively) for gaming. The general consensus is that framerates above 30fps make digital media appear more realistic (but can sometimes lead to the eerie “uncanny valley” aesthetic when combined with CGI – i.e. The Hobbit films, which are filmed at an unorthodox 48fps, rather than the traditional “cinematic” 24fps).
According to Simon Cooke on his personal blog – “The Accidental Scientist” – he feels that he has deciphered the reason many gamers prefer to play games at framerates above 30. It’s all rather complicated, but it has a lot to do with physiological reactions of the human eye.
Read more on why Cooke thinks 30fps isn’t enough for gaming after the break.
Xbox Software Engineer on Why 30fps Isn’t Enough
First, some information essential to understanding Cooke’s following explanation: In general, the human eye constantly jitters – known as “ocular microtremors” – in order to capture and interpret extra information (such as, say, a video game on a screen). Cooke states that the aforementioned ocular microtremors/oscillations occur at approximately 83.68Hz on average, which leads to his thoughts on why 30fps isn’t optimal for playing video games.
The following comes from Cooke’s previously mentioned personal blog (relevant, intersting information has been boldfaced:
If we accept that an oscillation of 83.68Hz allows us to perceive double the resolution, what happens if you show someone pictures that vary (like a movie, or a videogame) at less than half the rate of the oscillation?
We’re no longer receiving a signal that changes fast enough to allow the super-sampling operation to happen. So we’re throwing away a lot of perceived-motion data, and a lot of detail as well.
If it’s updating higher than half the rate of oscillation? As the eye wobbles around, it’ll sample more details, and can use that information to build up a better picture of the world. Even better if we’ve got a bit of film-grain noise in there (preferably via temporal anti-aliasing) to fill in the gaps.
It just so happens that half of 83.68Hz is about 41Hz. So if you’re going to have high-resolution pulled properly out of an image, that image needs to be noisy (like film-grain) and update at > 41Hz. Like, say, The Hobbit. Or any twitch-shooter.
Less than that? Say, 24fps? Or 30fps for a game? You’re below the limit. Your eye will sample the same image twice, and won’t be able to pull out any extra spatial information from the oscillation. Everything will appear a little dreamier, and lower resolution. (Or at least, you’ll be limited to the resolution of the media that is displaying the image, rather than some theoretical stochastic limit).
Essentially, Cooke is hypothesizing that if an eye oscillation/ocular microtremor of 83.68HZ allows humans to perceive twice as much detail (for the PC gaming-oriented – think of it as real-life supersampling), any framerate below half of that – which would be around 41Hz – such as 30fps in many console games, will cause the eye to lose much of the perceived motion and detail the scene (in this case, a game on a screen) needs to appear optimal.
Furthermore, for the greatest amount of visual fidelity, a scene/video game needs to have a framerate of at least 41, in additional to temporal anti-aliasing and “noise” (film grain), in order for the gamers’ eyes to extract the most detail.
You can read Cooke’s full blog post here. Beware, it goes into a lot more detail than what is shown above – but it is wildly interesting.
What are your thoughts on Cooke’s hypothesis on why 30fps isn’t enough for gaming? Is it a bunch of hokey data, or do you feel that it is relevant for gamers today?
Let us know in the comments section below! As always, stay tuned to Gamer Headlines for the latest in video game and technology news.