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New TestUFO animation simulating variable refresh rates

Posted: 22 Jan 2018, 20:56
by Chief Blur Buster
Hello,

I have now created a new TestUFO animation that simulates variable refresh rates on monitors that don't have VRR.

Check it out: http://www.testufo.com/vrr



It works best in a stutter-free web browser.
Chrome has a good stutter-detector (framerate number is green when not stuttering).
The animation is only accurate when the web browser does not stutter.

EDIT: New comparisons: Enjoy! And feel free to share with others.

Re: New TestUFO animation simulating variable refresh rates

Posted: 22 Jan 2018, 23:02
by yehaw
Can you add an option for the user to specify the frame rate instead of having it rise and fall? Really nice work though.

Re: New TestUFO animation simulating variable refresh rates

Posted: 23 Jan 2018, 07:27
by RealNC
Another improvement would be to have two bars, like in other tests. One with VRR on, one with VRR off, so that people can directly compare.

Re: New TestUFO animation simulating variable refresh rates

Posted: 23 Jan 2018, 11:16
by Chief Blur Buster
yehaw wrote:Can you add an option for the user to specify the frame rate instead of having it rise and fall? Really nice work though.
The framerate ideally has to keep changing to really demonstrate the benefits of VRR, since VRR eliminates the stutter of framerate-fluctuations.

However, I'll soon add extra options for different framerate varying patterns (slow ramp, fast ramp, random frame rates).
RealNC wrote:Another improvement would be to have two bars, like in other tests. One with VRR on, one with VRR off, so that people can directly compare.
Yes, I'm looking to try to add that feature.

Ramping framerates in non-VRR mode looks pretty stuttery. So having two strips above each other, directly comparing.

Re: New TestUFO animation simulating variable refresh rates

Posted: 23 Jan 2018, 12:07
by Haste
Could you explain how this works? (unless it's secret sauce info for now which I would totally understand)

Re: New TestUFO animation simulating variable refresh rates

Posted: 23 Jan 2018, 13:20
by Chief Blur Buster
Haste wrote:Could you explain how this works? (unless it's secret sauce info for now which I would totally understand)
An interpolation/blend algorithm. I'll spill the beans later this year, but I'll leave this air of mystery for now because... I'm first. ;) Stick around and you'll see explanations.

Unfortunately, this technique (interpolation) adds latency and latency-variance effects. So it's not really useful to do for games on non-VRR monitors. It's perfectly fine for motion tests, but as we all know, low latency is a big advantage of real hardware VRR.

So don't worry NVIDIA/AMD -- they're safe. :D

Re: New TestUFO animation simulating variable refresh rates

Posted: 23 Jan 2018, 19:25
by lexlazootin
Wow, this got a lot more neat once you said you blended frames together. Fooled me pretty hard. :lol:

My guess is that you blend the two frames and you separate them until you reach a multiple of the refresh rate, drop the fps and then you bring them together and start to separate them again.

Re: New TestUFO animation simulating variable refresh rates

Posted: 25 Jan 2018, 10:45
by Chief Blur Buster
Crossposting a good mini-reply here because this animation does an excellent job of demonstrating that stutter and display blur are both the same thing. (From a scientific phenomenon perspective)
Chief Blur Buster wrote:If at a high vibration rate, judder/stutter does blend into blur.

That"s what display persistence is: The high-frequency "stutter" of eyetracking across static refresh cycles. That is what it is when you watch motion on a 30Hz display or a VRR going down to 30fps (30Hz).

Regardless, the mathematics is the same for blurwidth (if blur) or edge-vibrationwidth (if stutter/judder). Both are still imperfections in motion either way.

Explanation: http://www.blurbusters.com/1000hz-journ ... ramplitude

And motion demo: http://www.testufo.com/vrr
Watch the high and low framrates.

Edge vibration of framerates:
Low frequencies vibrate visibly: it is motion stutter
High frequencies blend to blur: it is motion blur

Scientifically are the same phenomenon producing different effects. The difference is your flicker fusion threshold for edge-vibrating frequency. Low means visible stutter. But high is blur (invisible stutter vibrating at high frequences).

Like a slow guitar string (vibrates noticeably)
and a fast guitar string (blurry string because it is vibrating faster than you can see).

Re: New TestUFO animation simulating variable refresh rates

Posted: 26 Jan 2018, 02:22
by Chief Blur Buster
I've added different framerate varying modes:
Also, some slower systems (e.g. Intel integrated GPUs from 6 years ago) have some performance issues with this animation, so I've made some slight performance adjustments for full screen mode, to run in one-strip mode. This may also hold off my ability to do a versus animation, but the above should look good for now!

Re: New TestUFO animation simulating variable refresh rates

Posted: 27 Jan 2018, 19:00
by Chief Blur Buster
I've added the versus mode to testufo.com/vrr

Now you can compare VRR versus non-VRR fluidity!

Change the Versus setting to ON.