FCAT Frame Experience Analysis The Witcher III
With a benchmark technology called FCAT on the following few pages, we will look into Frame Experience Analysis. Basically with the charts shown we are trying to show you graphics anomalies like stutters and glitches in a plotted chart. Lately there has been a new measurement introduced, latency measurements. Basically it is the opposite of FPS.
- FPS mostly measures performance, the number of frames rendered per passing second.
- Frametime AKA Frame Experience recordings mostly measures and exposes anomalies - here we look at how long it takes to render one frame. Measure that chronologically and you can see anomalies like peaks and dips in a plotted chart, indicating something could be off.
| Frame time in milliseconds |
FPS |
| 8.3 | 120 |
| 15 | 66 |
| 20 | 50 |
| 25 | 40 |
| 30 | 33 |
| 50 | 20 |
| 70 | 14 |
We have a detailed article (read here) on the new FCAT methodology used, and it also explains whay we do not use FRAPS anymore.
Frametime - Basically the time it takes to render one frame can be monitored and tagged with a number, this is latency. One frame can take say 17 ms. Higher latency can indicate a slow framerate, and weird latency spikes indicate a stutter, jitter, twitches; basically anomalies that are visible on your monitor.
What Do These Measurements Show?
Basically, what these measurements show are anomalies like small glitches and stutters that you can sometimes (and please do read that well, sometimes) see on screen. Below I'd like to run through a couple of titles with you. Bear in mind that Average FPS matters more than frametime measurements. It's just an additional page or two of information that from now on we'll be serving you.
The Witcher III Frame Experience Analysis
Above, a percentile chart of the roughly one minute recording @ 2560x1440. In this particular chart we plot FPS and place it in relation to percentiles.
- For the tested card 50% of the time measured frames is just over 23 FPS. This you can consider the average framerate.
Above, the card at 2560x1440. You'll notice that part of the graph is outside the y-axis. Anything above 50ms is excluded as that is 20 FPS or lower. The Witcher III at WQHD with our image quality settings for the GTX 950 obviously isn't fair play. But it is the way we perform our FCAT tests. Anyway, this is the only title where it happens, overall everything below 50ms is looking good though (frametime wise lower is better).
