# Why more than 10 FPS is needed

As we know that out brain can process at most 1/10th of a second then why we go beyond the 10 FPS as our brain should not be able to process more than the 10 FPS of a scene. whats is the logic behind ?

• Just a little fun fact: the brain CAN process more than 10 FPS. Even the difference between 30 and 60 FPS is pretty clear. 30vs60.com Commented May 15, 2014 at 20:11
• I concur. When I was taking a senior-level computer graphics class in college, we were taught that the human eye starts to blur images at around 20 FPS, and it isn't until about 60 that you really start running into the limit for practical intents. The convention in the software industry is basically 15-60, and when I've tested software running at 15, I could always see the choppiness that 15 FPS presented. Commented May 15, 2014 at 22:23
• Linus can tell the difference between a refresh rate of 60Hz and 120Hz. Commented May 15, 2014 at 22:36

The brain can process an image displayed for as little as 13 ms if the surrounding content is blank. 10 to 12 images per second is only the number of images that appear distinct to the eye. Beyond 10 to 12 images a second, the brain starts to try to piece them together, but it is doing a lot of work to make that go and the motion isn't as smooth as it could be.

Using higher frame rates means that the brain has to do less filling in the gaps and motion can appear more accurate and smoother since the brain is actually fully capable of processing images faster than 10 times a second.

The 12fps animation threshold is only a minimum to get the appearance of motion, not the maximum amount of information our brain can take in. We can process far more images per second to determine motion, but require at least 10 to 12.

You can test this for yourself if you want by taking a 30 fps video and inserting a black frame at random in the video. You'll easily notice the distortion from the missed frame because it abruptly changes to something other than the expected image.

Basically your brain knows what it expects to see and can recognize that it didn't see what it expected, it just can't recall exactly what it is that it saw that it didn't expect since it was taking a shortcut to reduce the amount of processing needed.

The Wikipedia article on frame rate is a good source of additional information on the topic.

The logic of experience. All you have to do is watch 10fps or even 20fps video to realize that what you "know" to be true of the brain is wrong. Persistence of vision in the average human dictates a refresh rate of > 25fps to avoid apparent flicker.

The human visual system involves more than just what the brain can completely process.

If a person is shown consecutive pictures of a featureless circle at various places on a screen, the person may perceive independent circles appearing and disappearing, one circle which is making discrete (jerky) motions, or one circle which is moving smoothly. Which perception dominates will be a function of both the rate at which the screens are shown and the ratio of the circle's size to the distance it moves between frames. The higher the frame rate and the less the circle moves between frames, the less opportunity there will be for the eye or the brain to notice any difference between what a smoothly-moving circle would do and what the observed image is actually doing.

If one goes beyond a featureless circle to more detailed objects, the analysis will become more complicated, but largely boil down to a key observation: the amount by which an object can move between consecutive frames without appearing jerky will correlate strongly with the size of the object's dominant features. A 12fps or even 8fps rate is adequate when showing blurry objects, but even 30fps may be inadequate when the features of an object appear at substantially-non-overlapping positions on consecutive frames.

Incidentally, showing black between frames, rather than changing directly from one image to the next, will often improve the perceived smoothness of motion, but (except at high frame rates) at the expense of introducing flicker. Essentially, during the time the image is black neither the brain nor the eye will be able to see anything that would be inconsistent with continuous motion.