I see the same arguments arise about HFR as I do with stereoscopy and the rhetoric follows the same as the switch from vinyl to digital music formats: it is no longer art. It feels like you lose the artistic effect when you add a multiple of information to your brain. The reality is artists need to learn how to be mindful of the new medium and the old tricks they used to overcome older medium defects need to be removed from the process. (Ex. Over use of makeup) I am excited because we have a bright future with better media technology and pioneers like James Cameron are leading the way.
Why movies look weird at 48fps, and games are better at 60fps
21–30 of 129 posts
Re: Why movies look weird at 48fps, and games are better at 60fps
#22The most interesting point made in the article (for me) is that the presence of noise/grain - which effectively reduces real detail in an individual image - can actually improve the perceived detail across time with high frame rates.
At first, I thought this extra "detail" could be explained as an illusion (since noise/grain can mask a lack of resolution), but then I read the abstract quoted near the end of the article:
"...visual cortical cell responses to moving stimuli with very small amplitudes can be enhanced by adding a small amount of noise to the motion pattern of the stimulus. This situation mimics the micro-movements of the eye during fixation and shows that these movements could enhance the performance of the cells"[1]
So if I understand right, since the biological systems are tuned to extract extra detail via supersampling across time, and a small amount of noise/grain can enhance that ability (mimicking natural movement of the eye), it actually helps our visual system extract more real detail.
It seems counterintuitive to add noise for more detail, but the explanation is fascinating.
[1] Stochastic resonance in visual cortical neurons: does the eye-tremor actually improve visual acuity? – Hennig, Kerscher, Funke, Wörgötter; Neurocomputing Vol 44-46, June 2002, p.115-120
Re: Why movies look weird at 48fps, and games are better at 60fps
#23Most serious FPS gamers swear by screens that have a higher update rate than 60hz. In the past this was achieved by setting your CRT to a low resolution and upping the refresh rate. More recently you can get TN LCD panels that offer 120 or 144hz update rates. Moving the mouse in small quick circles on a 144hz screen compared to a 60hz screen is a very different experience. On a 60hz screen you can see distinct points…
Wait a second.. can you explain the 10x the max frequency part to accurately reconstruct the shape of the signal? It's my understanding that you just need 2x (two points in a sine wave) to construct a unique wave. If you're getting a sawtooth, it means that you're sampling a wave that is composed of very high frequencies, and you're accurately sampling it, so a DAC can reconstruct it uniquely.
There's some discussion of it at the beginning of this article: http://www.ni.com/white-paper/10669/en/
Re: Why movies look weird at 48fps, and games are better at 60fps
#24I personally love HFR and have went out of my ways to watch the three The Hobbits in HFR (I traveled to Paris, the only place in France where they have it in HFR).
When people complain about 48fps being weird I just feel like they're just not used to it. It does look weird but after 20 minutes it looks amazing. I'm personally tired of not understanding anything in action movies that uses 24fps. It is kind of a luxury for the eyes to have 48 fps and I predict that in a few years we'll have the same debate we have with console now (60 fps is better than 30 fps).
We got used to 24 fps and so we're making justifications on why it looks better when it clearly doesn't if you take a step back.
Re: Why movies look weird at 48fps, and games are better at 60fps
#25I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments:
Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time.
This is something that, once stated, is blatantly obvious to me, but it's something I simply never thought deeply about. What it's saying is that when you render a frame in a game, say the frame at t=1.0 in a game running at 60 FPS, what you're doing is capturing and displaying the visual state of the world at a discrete point in time (i.e. t=1.0). Doing the analogous operation with an analogous physical video camera means you are capturing and compositing the "set of images" between t=1.0 and t=1.016667, because the physical camera doesn't capture a discrete point in time, but rather opens its shutter for 1/60th of a second (0.16667 seconds) and captures for that entire interval. This is why physical cameras have motion blur, but virtual cameras do not (without additional processing, anyway).
This is obvious to anyone with knowledge of 3D graphics or real-world cameras, but it was a cool little revelation for me. In fact, it's sparked my interest enough to start getting more familiar with the subject. I love it when that happens!
Re: Why movies look weird at 48fps, and games are better at 60fps
#26Most serious FPS gamers swear by screens that have a higher update rate than 60hz. In the past this was achieved by setting your CRT to a low resolution and upping the refresh rate. More recently you can get TN LCD panels that offer 120 or 144hz update rates. Moving the mouse in small quick circles on a 144hz screen compared to a 60hz screen is a very different experience. On a 60hz screen you can see distinct points…
2 samples of a sine wave does not result in a sawtooth wave being reproduced by the DAC. A perfect sawtooth wave actually contains infinitely high frequency content and thus can't be perfectly represented digitally.
Check out this video http://xiph.org/video/vid2.shtml which was recently posted here. Also the wikipedia page on sawtooth waves has an animation showing additive synthesis of a sawtooth wave: http://en.wikipedia.org/wiki/Sawtooth_wave
Re: Why movies look weird at 48fps, and games are better at 60fps
#27Earlier quoted context omitted.
Wait a second.. can you explain the 10x the max frequency part to accurately reconstruct the shape of the signal? It's my understanding that you just need 2x (two points in a sine wave) to construct a unique wave. If you're getting a sawtooth, it means that you're sampling a wave that is composed of very high frequencies, and you're accurately sampling it, so a DAC can reconstruct it uniquely.
There's some discussion of it at the beginning of this article: http://www.ni.com/white-paper/10669/en/
This paper has a lot of false information in it. The sawtooth wave example is just not correct. There is exactly one band-limited (i.e. no frequencies greater than half the sampling frequency) waveform that corresponds to a set of samples. In the case of a sine wave sampled at twice the frequency, that solution is the exact sine wave that was produced. The video I linked to above has a demonstration of this signal reconstruction, using an analog oscilliscope to show that sine waves are reconstructed perfectly when sampled at only 2x the fundamental frequency.
Re: Why movies look weird at 48fps, and games are better at 60fps
#28I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…
Not sure about how movies are filmed, but you don't have to shoot video frames at 1/FPS. That's just the slowest you can shoot. If you're shooting in broad daylight, each frame could be as quick as 1/8000, for example.
Shooting at the slowest shutter speed possible should make the most fluid video.
Re: Why movies look weird at 48fps, and games are better at 60fps
#29Earlier quoted context omitted.
Wait a second.. can you explain the 10x the max frequency part to accurately reconstruct the shape of the signal? It's my understanding that you just need 2x (two points in a sine wave) to construct a unique wave. If you're getting a sawtooth, it means that you're sampling a wave that is composed of very high frequencies, and you're accurately sampling it, so a DAC can reconstruct it uniquely.
There's some discussion of it at the beginning of this article: http://www.ni.com/white-paper/10669/en/
Ah ok, so here I think is the slight confusion.
If you make the constraint/assumption that during reconstruction that you rebuilding a time domain signal composed of series of sinusoidals, then you're in the clear at just 2x sampling. For example, in Figure 2 in the article, it states that 2x sampling only provides frequency information, and not amplitude and shape. This is true if we assume that we're trying to directly reconstruct -any- periodic signal. Then if we sample at only 2x of the signals fundemental frequency, we are in fact stuck.
This can cause certainly cause confusion. So I think the usual way (I just dinker with DSP for funsies and a little bit at work, so I might have got it mangled) to deal with this confusion is to remember that sawtooth and square (and whatever) signals are chocked full of high harmonics that also must be sampled at or beyond the nyquist limit for you to be able to construct it.
Re: Why movies look weird at 48fps, and games are better at 60fps
#30I liked the article, but, as a game developer who does not specialize in graphics, I really liked one of the comments: Joe Kilner - One extra issue with games is that you are outputting an image sampled from a single point in time, whereas a frame of film / TV footage is typically an integration of a set of images over some non-infinitesimal time. This is something that, once stated, is blatantly obvious to me, but i…
I always use this fact as a kind of analogue to explain position-momentum uncertainty in physics. From a blurry photo of an object, you can easily measure the speed, but the position is uncertain due to the blur. From a very crisp photo, you can tell exactly where it is, but you can't tell how fast it is moving because it is a still photo.
It's a good way to start building an intuition about state dependencies.