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Ultra High Definition Video
mr.henry writes "Engineers at the Japanese Broadcasting Corporation (NHK) have developed a prototype ultra high definition video (UHDV) system. How good is it? When it was shown to the public, some viewers experienced nausea because of the ultra realistic visual effect of speed without the usual physical sensation of movement. 18 minutes of UHDV takes up 3.5 terabytes." 4,000 horizontal scanlines. Excellent.
Here's the explanation, for those who missed out on this one.
How about 48 fps?
I know the parent was a joke, but just some info:
since the human eye has on the order of 100 million rods/cones, it should have a maximum resolution of about 10 000*10 000 pixels if the object you are looking at fills your entire field of view.
True, the majority of rods/cones (cant remember which is which) only see shades of gray, but when you combine this ability with the color-sensing of the central 6 million or so, you get a nice synergistic effect which lets you enjoy the full resolution... (only in well-lit environments though)
and even though the "no need for more than 24 fps"-argument should be dead by now:
24 fps is the MINIMUM fps required for the eye to percieve "natural" motion from static images.. not the maximum needed.
when the NHK R & D center held its open house. They also had a very small OLED display on hand, but it wasn't nearly as impressive as this display.
And it is awesome. I didn't experience any nausea, but the scale and clarity of the image did throw me a bit, as it is VERY realistic. Beats the pants off 35mm film. Other than sheer size, IMAX has nothing on it.
They had the camera set up in the previous room, live on an object. Walking into the next room was like seeing the same object, except larger. The video was of the surrounding city and Shibuya. Watching the people cross the intersection was incredible, blew even IMAX away.
It is crystal clear. No flaws in the video, no flicker, no exposure flaws at all on the video. Only downside is the massive computer system in the back that has to be used to control it. I imagine that this too will shrink over time.
Actually, some movies HAVE been shot at 60fps (or at least sections of them). "Brainstorm" was one such film.
In fact, Douglas Trumball as at one time a very vocal advocate of trying to get Hollywood to transition to 60fps.
Too bad it did not happen. There are PLENTY of advantages to doing so.
Here is a quote from the October 2003 issue of Digital Video. "24p: Back to the Future?"
"When Douglas Trumbull developed Showscan (70mm at 60 fps) in 1976, he noted a profound psychological reaction among his test audiences when the frame rate hit 60 fps: The film ceased to be a film and was more like a window into reality: It just wasn't any good for storytelling, Trumbull claimed. Showscan was thus relegated to theme park immersive venues, and a grand experiment in theatrical storytelling frame rates was shunted aside.
There's little doubt that it was a progressive frame rate. There is no CRT in the world that would be capable of resolving that. I highly doubt they used a number of side-by-side CRTs. It seems very likely that they showed it on some sort of digital display technology (DLP, LCD, D-ILA, etc.). All of these technologies are inherently progressive. Any interlaced signal must be de-interlaced for them to display it.
I agree that it would be fantastic to see >24fps in movies. There is just to much money and infrastructure dedicated to the 24fps standard right now though. I highly doubt that we will EVER see a significant number of motion pictures shown at >24fps on film. The story could be very different as directors migrate to HD video to make thier pictures however.
In answer to your questions:
There is no exact "frame-rate" of the human eye, because different parts of the eye respond differently to change, some parts have higher refresh than others. This is why screen-flicker is easier to detect by looking at a screen sideways (the edge of vision has higher refresh rates, probably an evolutionary left-over, being able to detect movement quickly near the edge of vision is the closest we can come to having eyes on the back of our head).
As for resolution, this is highest near the center of your eye's field of view, and is mainly dependant on how close together the light-sensitive cells are in the middle of the eye. In practical terms, max resolution of most people's eyes is a couple of arc-minutes (1 arc-minute = 1/60 of a degree). To put this in real terms, 1 arc-minute is the angular size of an object when viewed from a distance 3437x its size, so a 1.8m (6ft) human being seen at 6.2km (3.9 miles) is about an arc minute high.
For a Computer monitor, that means that people with good vision (say 2 arc minute resolution) sitting 1 foot (30cm) away from a monitor, should be able to distinguish a pixel 0.09mm (0.0034") across, but only just. Typical LCD-screens have pixels 0.25-0.30 mm across.
There's so much wrong with that post, where should I begin? For one thing theater movies are 24fps, not 25fps, and for another, each frame isn't displayed "three times," it's displayed once -- the projector shutter closes in between every frame. Since our eyes aren't quick enough to process the film frame and the black shutter as separate images we think we see the film frame twice, for an effective frame rate of 48fps.
The specs are 7680x4320 (16:9 aspect ratio, just like HD), 60 progressive frames/sec.
r 2003/Ultra/Ultra38.htm
Check the original paper at:
http://www.studio-systems.com/broadfeatures/MarAp
If you assume 16bits for Y and 8bits each for U and V (ie 4:2:2 encoding) it works out to 4bytes per pixel, which gives you 33.75fps. Now if you start with 30fps progressive or 60fps interlaced and work backwards you get to 3,110,400,000,000 bytes uncompressed assuming 32 bits per pixel. Or you can get 60fps progressive if you work with 16bits per pixel (standard tv color depth). So my guess would either be 60 fields per second interlaced, with 32 bits per pixel, or 60 frames per second interlaced with 16 bits per pixel.
Now as much as I hate interlaced video, at over 4000 lines you really wouldn't be able to see the interlacing, and it would be worth it for the increased color depth and stay at 60fps.
Basically this system would knock your socks off, maybe even your shoes.
-matt
Well, from a purely technical perspective, 60 fps would be nice, but there are big drawbacks:
2.5x as high film costs
1/2.5 as many minutes of shooting between changing film canisters
2.5x higher light requirements for the same grain, since each exposure would only be 1/120th of a second. High light requirements are quite expensive, because of the additional setup required. The greater light sensitivity of CCD v. film is one of the big reasons behind the misnamed "DV revolution."
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