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Human Eye's Oscillation Rate Determines Smooth Frame Rate
jones_supa writes: It should be safe to conclude that humans can see frame rates greater than 24 fps. The next question is: why do movies at 48 fps look "video-y," and why do movies at 24 fps look "dreamy" and "cinematic." Why are games more realistic at 60 fps than 30 fps? Simon Cooke from Microsoft (Xbox) Advanced Technology Group has an interesting theory to explain this all. Your eyes oscillate a tiny amount, ranging from 70 to 103 Hz (on average 83.68 Hz). So here's the hypothesis: The ocular microtremors wiggle the retina, allowing it to sample at approximately 2x the resolution of the sensors. Showing someone pictures that vary at less than half the rate of the oscillation means we're no longer receiving a signal that changes fast enough to allow the supersampling operation to happen. So we're throwing away a lot of perceived-motion data, and a lot of detail as well. Some of the detail can be restored with temporal antialiasing and simulating real noise, but ideally Cooke suggests going with a high enough frame rate (over 43 fps) and if possible, a high resolution.
You cannot "evolve" from slime into a monkey then give birth to a human. Basic science FACT!
I, for one, am sick of slow (seconds-long!) pans across scenery that *still* end up with judder and motion blur.
HFR isn't a gimmick like migraine-inducing stereoscopic "3D", it's more akin to adding color instead of relying solely upon greyscale for film presentation.
Like all tools, I'm sure it can be used for both good and evil. Blame evil, jump-cutting directors if the dark side is channeled.
Movies tend to be shot around 1/50" shutter speed, and that creates motion blur. The motion blur actually helps us see the animation as smooth, even at "only" 24 fps. Games on the other hand are razor sharp and will hence look much more like a staccato sequence of images than as an animation.
Or so I was told by a moviemaker
What was the presumed order of "occurrence" of the oscillation hardware mutation and the supersampling "firmware" brain mutation?
... is why cinema frame rates seem generally comfortable to watch, while video game frame rates at around the same number are problematic?
File under 'M' for 'Manic ranting'
What about our eyes is oscillating?
- Zav - Imagine a Beowulf cluster of insensitive clods...
It would take hundreds of frames per second to truly fool the eye. We tend to have long decay, which I believe offers a hardware solution for "Where is it coming from?" but human attack FPS is much higher than you might think.
https://www.youtube.com/c/BrendaEM
This makes sense. One of the things that drives me nuts about those cheap Chinese no-name Android tablets is the display. They draw every other pixel in a checkerboard type fashion, and if your eye is totally still then you don't notice. However if you move your eye quickly back and forth you can clearly see that only half the pixels are drawn at a time. So there's something about the motion that doesn't allow enough processing time to smooth that out. It's amazing how much our visual processing smooths things and even totally fills in parts that aren't even visible, but that requires an image to be steady at least to some degree.
Better known as 318230.
The smoothest frame rate would be no frames. 2,073,600 analog tracks, one for each pixel of a 1080p display would smoothly transition from one color to another. OK, so maybe the recording tape would be 3 feet wide. But a small price to pay for smooth video.
-- Thou hast strayed far from the path of the Avatar.
between the tremor frequency and the frame rate?
why do movies at 48 fps look "video-y," and why do movies at 24 fps look "dreamy" and "cinematic."
For the same reason children are picky eaters. They say that people have to take three bites of a new flavor to really know if they like or dislike it. I have personally experienced that, going from "wtf this is so wrong" to "ok it's not so bad and I might actually like this" between bite 1 and bite 3. Well, we all grew up consuming 24 fps movies, and anything higher is new and different. Rather than "take three bites", though, so many of us recoil from the different experience and immediately start talking to all our friends about how it looks wrong, concluding that high FPS just looks bad. Try. Three. Bites.
I sometimes ask revealing, often ignorant-seeming questions. Maybe they're harder to answer than you think.
Anyone that has done mushrooms can tell you that seeing the world at the frame rate that the brain is capable of processing is a load of fun. I have no idea how psilocybin affects the visual processing center of the brain -- or hell, it may affect the eye itself, what I do know is stepping out into a room and looking around without the brain discarding the frames that it doesn't feel like processing is amazing. However, it does look completely fake. It is too clear / crisp. Our brains aren't used to seeing every little change -- they discard information. So, if you are watching a movie at 48 or 60fps, it looks fake is the best way I can describe it. That is because when you are looking at the screen, you have a central place to focus, and my guess is the brain doesn't discard information if you aren't moving.
Again, this is just my guess, but I think the reason video games look much better at high frame rates is the fact that they already don't look realistic. We are expecting really crisp, sharp, fast graphics. Literally -- it is all in your mind.
As a test, pan your head from left to right and notice the "jumpiness" that is reality. Now, eat about a half gram of shrooms, and do the same thing. It is no longer jumpy, and you get a REAL smooth pan.
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There are several ways to apply temporal antialiasing or "motion blur", each of which is analogous to a well-known spatial antialiasing method. One is to render the scene twice at a slight time offset and average the two; this is the temporal counterpart to FSAA. Or find the motion vector around the frontmost mesh in each 8x8 pixel section of the screen and add a local blur filter; this is more like MSAA. But in the march from 240p (PlayStation and Nintendo 64) to 1080p (current consoles) and higher (PC master race), the preference has been for more detail in each frame rather than a better illusion of motion within a frame.
The old Bell & Howell 16mm projectors (24 fps) actually projected at 72 fps (call it flashes per second). The projector had a 3 bladed circular shutter. The film was pulled down one frame while the shutter was closed with one blade, then as the shutter rotated the frame was 'flashed' 3 times, then the next frame pulled down and the process repeated. The human eye could see flicker at 24 fps but not so much at 72. The video experts here can correct me, but I believe standard NTSC video was 30 fps of 'data' scanned twice to give 60 to reduce perceived flicker.
It's not about flicker, it's about the smoothness of motion.
systemd is Roko's Basilisk.
At 48Hz, you’re going to pull out more details at 48Hz from the scene than at 24Hz, both in terms of motion and spatial detail.
Motion yes, but spatial? I don't get that bit.
[at 24Hz] We’re no longer receiving a signal that changes fast enough to allow the super-sampling operation to happen.
Err, what? You're not supersampling if the data has changed between the two samplings.
To answer the question posed in the headline:
Why movies look weird at 48fps
Because it's not what we're used to when we go to the movies. That's all.
systemd is Roko's Basilisk.
Don't confuse science with religion. They have nothing to do with each other. There are people that view science as religion, or others that view religion as science. Both are equally wrong.
Science is knowledge, ever changing since we don't see the whole picture.
Religion is dogma. Fixed, at least for duration of one's lifetime. But still, it changes just so religion can survive. Dogmas of 1000 years ago are not dogmas today.
Anyway, you may want to refer to official statements of Catholic church on this, that evolution has nothing to do with contradicting religion.
http://en.wikipedia.org/wiki/C...
On October 27, 2014, Pope Francis issued a statement at the Pontifical Academy of Sciences that "Evolution in nature is not inconsistent with the notion of creation," warning against thinking of God's act of creation as "God [being] a magician, with a magic wand able to do everything."
In an October 22, 1996, address to the Pontifical Academy of Sciences, Pope John Paul II updated the Church's position to accept evolution of the human body:
"In his encyclical Humani Generis (1950), my predecessor Pius XII has already affirmed that there is no conflict between evolution and the doctrine of the faith regarding man and his vocation, provided that we do not lose sight of certain fixed points.... Today, more than a half-century after the appearance of that encyclical, some new findings lead us toward the recognition of evolution as more than a hypothesis. In fact it is remarkable that this theory has had progressively greater influence on the spirit of researchers, following a series of discoveries in different scholarly disciplines. The convergence in the results of these independent studiesâ"which was neither planned nor soughtâ"constitutes in itself a significant argument in favor of the theory."[46]
In the same address, Pope John Paul II rejected any theory of evolution that provides a materialistic explanation for the human soul:
"Theories of evolution which, because of the philosophies which inspire them, regard the spirit either as emerging from the forces of living matter, or as a simple epiphenomenon of that matter, are incompatible with the truth about man."
Since soul is an ephemeral notion that has nothing to do with science, catholic view is not going to clash with science. You see, they have learned from their earlier mistakes which included apology that Earth is in fact round, not flat and does go around the Sun.
So, follow the catholic church on this. Human body evolved from monkeys or whatever. God created that human soul. And since it's the soul that matters, not the body, there is no problems.
But if you try to point to things like "human eye is proof of God perfect design", then you will just make a fool out of yourself (or if you point at anything physical as proof of God). Just to counter the eye issue, the eye as evolved to function in water, no air. Fish see a lot better than people. Plenty of animals don't have blindspots - their eyes evolves so optic nerve connections don't go in front of the retina, unlike the inferior human eye. So if human eye is perfection of design of God, why do lower animals have much better eye both in design and function?
It still good to ponder what flicker could tell us. For example, the 200 Hz LCD backlight PWM frequency causes sore eyes and headaches to many people, so certainly the eyes and/or nervous system are sensing something? Put some white text on a black background on a computer like that and you can see multiple images of the text when rapidly turning eyes horizontally. Of course, as you say, the picture appearing and disappearing is largely a different discussion when compared to motion sensing, but there might be a bridge which can combine these discussions for some benefit.
Before civilization, people lived in villages for tens of thousands of years and lived in terrror of their neighbouring villages liable to attack at any time. This terror of space was ended when civilization ceased the fear that the next town over might attack. The fear was then attached to time, and people focused on the fear of the future, so religions developed to sell them insurance to offset the risk of future catastrophe.
Without this small oscillation of eyeballs images would be stabilized on the retina and thus fade and eventually disappear. Or reappear when unnecessary. The author of the linked article doesn't mention this fact, but it was discovered by a Soviet scientist in the 1960s and at the time was considered controversial.
24 fps is the speed at which the film travels through the "gate" (mechanical or electronic). When projected for viewing the frame rate is bumped up (progressively) to 50 fps, which is more than adequate to interpret the image.
I'm wondering if whether this is really an of interlaced vs. progressive presentation. For video engineers, interlaced works somewhat more naturally for sports, where the camera and the principals are in constant motion.
At any rate, whatever Peter Jackson is doing with higher sampling is unnecessary and uncomfortable to watch for an extended time.
I say the human eye does see more than 24 fps, pan your head back and forth, no blurring like you get panning a camera. OK so I haven't RTFA but I recently read/search info on framerates. From what I gather 24 fps came about from movies particularly when the talkies became standard for motion pictures. What they settled on enough fps to have smooth action and matching audio but not too much as film is/was very expensive. But each frame is shown twice (refresh rate in the movie theatres is 48 Hz). I read 24 fps is needed so brain perceives as smooth motion but need to show each one twice to remove flicker effect. Those 16mm and silent films were less fps but not as cinema quality of major motion pictures.
Anyone have comments or corrections, jump in as many times I feel as if I'm still trying to figure out what and why of fps and refresh rates.
Then television came along, first 60 fps seems good (match with powerline freq) but too much bandwidth so they make it 30 fps but to reduce flicker, they did interlace. Framerate has smooth motion and interlace does the refresh rate like motion picture showing each frame twice. Then color TV comes along but as OTA bandwidth was fixed, they reduce framerate a little to 29.97 to insert chroma signal.
Then computers came along, why not use same CRTs as TV sets, so their framerate was 29.97 (but many simply rounded off to 30 when writing or talking about framerates). Then the flatscreens (VGA monitors) came along but used 29.97 to be compatible with existing computers, but refresh rate is 60 Hz to not have flicker effect. Gamers wanted higher framerates so 60 fps but I think it really is 59.94 fps.
I did some different FPS exercises with a CRT monitor and a Canon EOS camera. I set Canon to 30 fps (actually it is 29.97) and connected the video output to the monitor. I panned camera back and forth including viewing monitor. I did the same with Canon at 24 fps, there was noticable blurring or choppy on monitor when I panned camera back and forth. Viewing monitor with camera I can see those rolling bars like you see in the movies with TV set in background (aha, so that's what the 24/30 fps mismatch is). I set camera to 60 fps (actually 59.94), it seemed smoother view when panning back and forth though monitor is fixed 30 fps.
For many people, so what. However, I was looking at various cameras and spec sheets list framerates of 23.97, 24, 29.97, 30, 59.94, 60.... what's with all these variations? I don't think a camera can be set to exactly 30. Or is it sales and marketing people insists on lots more numbers for the spec sheets?
mfwright@batnet.com
'It should be safe to conclude that humans can see frame rates greater than 24 fps."
We can go even faster than that.
While this video I just shot won't show it very well due to FPS limitations, you can easily perceive much faster than anyone here assumes. In the frequency range I'm playing in, you've got THOUSANDS of hertz in difference on some of these notes. The LED setup makes it REALLY easy to see in real time.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
The ear follows the rules Nyquist created about sample rates (i.e. there are hairs in your ear that are turned to hear 40 kHz but you can't hear that high). There is no reason the eye can't be doing the same thing.
Because I can damn well assure you there is a huge difference between 30 FPS and 300+ FPS.
OK, I play twitch games but this is where it matters. It's not about what the eye can perceive but about the physical interaction and muscle training. Our brains/muscles/whatever react and control much more accurately than even a game at 300 FPS can simulate. To restrict us to artificial eye-visual frame rates is stupid.
While we're on the topic. How about more fluid games? iD/Carmark got it right. Smooth, fluid, natural gameplay. Nowadays all we get is the stiff robotic games that feel like shit. What the hell people, can you seriously not tell the difference? All you want is awesome graphics with crap feel? Kids are so stupid. We have been through this already, dammit.
I think the problem is that because we're so used to 24 fps on theatrical motion pictures, going to 48 fps can be quite jarring, since everything looks so much "clearer" that you have to rethink set design, costume design and even the use of special effects to be less obtrusive at 48 fps. (Indeed, this became a huge issue with Peter Jackson's "Hobbit" trilogy because everything looked TOO clear.)
The late Roger Ebert liked the 48 fps "Maxivision" analog film format, but that idea never took off due to need to use a lot more physical film and the increased stress of running a film projector at twice the speed of regular projectors. But with modern digital movie cameras, 48 fps is now much more viable.
make movies look like they were shot on a daytime TV cam to me. I saw Braveheart on one of those modern tvs and I suppose the lighting was more natural, but it was considerably less dramatic. It just killed it for me. Also (and this is mostly just me) I can perceive noticeable drops in framerate on those newer tvs. The rate goes up and down like crazy. Drives me nuts.
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The competition was 16 fps which would have been 33% cheaper to film.
Edison sold film supplies in those days.