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A Billion-Color Display
The Future of Things covered the introduction last month of HP's DreamColor display, with 30 bits/pixel, developed in conjunction with DreamWorks Animation. The display is aimed at the video production, animation, and graphic arts industries. HP promises blacker blacks and whiter whites — though TFoT quotes one source who notes that if they deliver this, it will be due to the back-lighting and not to the number of bits/pixel. No word on the size of the displays that will actually be delivered, or on the price.
And yet that 24bpp can't reproduce the full range of colors that can be printed on a piece of paper. And the ink on that piece of paper can't reproduce the full range of colors visible to the naked eye. Yes, there's room for a whole lot of improvement. That's not to discount the progress we've already made (24bpp is pretty impressive), but there's still a long way to go.
This guy's the limit!
how am I supposed to see how good this display is if they don't show me a picture of it?
Most new displays have a resolution of 96dpi, whereas low-end printers can easily pull off 300dpi. Same goes for color-depth. Black and White screen images at 8 bits/pixel simply cant match the range of black&white print & film.
When you think about it, techniques such as anti-aliasing are really just hacks to work around the limitations of today's monitors. If monitors could pull off 300dpi, you wouldn't need anti-aliasing.
I know you're jesting, but our eyes are definitely capable of appreciating 30 bits, and many megapixels as well. Our eyes don't work like cameras; we're excellent at discriminating fine differences within the area we're looking at. We might not be able to tell #cc1111 from #cd1111 in isolation, but if they're right next to each other we can see that difference and more.
(On a similar note, in the center of our visual field, we can discriminate physical positions with much greater accuracy than the receptor density would lead one to believe, because our analog receptors are capable of discerning fine differences by working with their neighboring receptors. So anybody who says "X resolution is higher than humans can see" is talking out of his ass. You can tell when they know what they're talking about when they say something like "at this resolution, most humans will only be able to perceive a 1-pixel difference 60% of the time" or something which sounds a lot more like signal theory than somebody comparing one arbitrary number to another arbitrary number.)
Just as in audio where quantizing becomes a problem only in very low level passages, fine greyscale, especially in the blackest image areas, will benefit from more bits/pixel.
For example, an ordinary CD (16 bits) can sound rather gritty on quiet recordings such as the low level passages of classical music. That's because you're probably only using two or three bits of sample depth down there. To combat the issue, 24 bit audio will elevate the sample depth everywhere but will show itself best at low levels. Dither (essentially noise) is used to randomize and mask the problem, but that's a cheat.
In video, fine greyscale performance comes from higher bit depth per pixel and is visible throughout the entire luminance range. The issue shows itself on flat (un-textured) areas with minute lighting changes across the surface, like a softly lit painted wall. You'll see annular rings on the surface as the bit values step through their range. Again, dither may be used to randomize the quantized transitions.
24 bit video is really 8 bits per primary color - so it's not that good to start with. In professional application, it's not unusual to work with 10 bit [per channel] or even up to 16 bit[per channel] images, mostly to be more friendly to post production.
Fortunately, analog humans are fairly blind to minute color changes. Unfortunately, our system of digital video happily shows you everything wrong with it.
Most of the stuff on
I did, with clear plastic add-ons. I've got a friend who went with the laser upgrade.
I see your informative link, and raise you a pithy comment.
Modern monitors use an additive method of color blending, while printers (by their very nature) must use subtractive blending.
The range of colors that can be reproduced by a 24-bit RGB device is always going to be different from the range of colors that a 24-bit CMY device can reproduce.
By the same note, a 24-bit RGB display can produce colors that the CMY printer cannot.
One color space isn't bigger than the other; they're simply different. Once you increase the bit-depth far enough to encompass the full spectrum of visible light for both color spaces, the distinction can finally be dropped.
-- If you try to fail and succeed, which have you done? - Uli's moose
Nope, just higher resolution.
I see your informative link, and raise you a pithy comment.
They're absolutely right that CMYK does not encompass RGB. They overlap for a large part, and don't overlap in small areas (with one larger area in the deep vivid cyans).
However, a larger bitdepth doesn't do anything for color space. It simply determines the granularity of that color space. If with 16 bit you get 65,536 individual colors within the RGB gamut (with slightly higher granularity in the green channel, typically), and with 24bit you get 16,777,216 individual possible colors within the RGB gamut, then with 30 bit (10 bit per channel; it's not new, really), you get 1,073,741,824 individual possible colors... but still within the RGB gamut (of the device at hand).
An HDR display (either by using a very bright backlight or more localized LED backlights control, etc.) also doesn't change the gamut of that device - it simply allows for much brighter values of them.
Now, if they were to make an LCD panel that aside from the R,G,B pixel elements also had C M Y pixel elements, then you most certainly could increase the gamut. It would also be much more difficult to switch to than a simple bitdepth change.
Again, read this.
As for the 1600, the trade-off you have for a true 24 bpp display is narrower viewing angle and slower response time, this is due to the physics of the crystals. Check out the National Semi page for lots of info on what exactly a liquid crystal is, what the different types are and how they're driven, and lots of amusing info on the guts of LCD panels.
But for the dithering, it's sort of like buying CDs with 16 bit samples, but CD players only having 12 bit DACs but it not being written anywhere. But then, if no one can tell, why choose 16 bits in the first place? This reminds me of the waning days of Minidisc when suddenly everyone here became a very critical, golden-eared audiophile and could tell the difference between a CD and MD, but the same people turn around to their 18 bit displays, can't tell the difference, and go on thinking they are 24 bits.
Life on this planet never ceases to amaze and befuddle me.
Mostly random stuff.
Human brightness sensitivity is not even close to constant across the total range of brightness we can perceive. It varies widely over the range of colours we can see, and from person to person. Scene composition affects it, too: the shape of an object in relation to nearby objects changes our perception of its brightness. You have to consider lateral inhibition, limited integration capability, the optical modulation function of the eye, and orientation and temporal filtering, not to mention the various forms of noise that affect all parts of the vision system. The human vision system is not a camera and trying to model it as one is extremely naÃve.
With all that warning out of the way, the greyscale Just Noticeable Difference for a monitor of about 600cd/m^2 is equivalent to 720 steps.
For a 1024 steps, the monitor would need a peak intensity of around 4000 cd/m^2 to match the greyscale step increase with the statistically average human just noticeable difference.
"No one likes working in a hamster wheel, and your shop smells of cedar shavings from here." - TaleSpinner
while a billion colors is obviously ridiculous, there are people who can see 100x more colors than an average person
scientists have recently identified a very small, very rare population of women who see in 4 colors, to a total of 100 million colors
most humans see in 3 colors, about 1 million colors: red, green, and blue. a tetrachromat has an extra cone type between red and green, around orange. it's only women because the mutation requires two x chromosomes to work
read all about it, they describe a women who can look into a river and make out silting and depth levels a normal human can't, x-men mutant indeed!:
http://www.post-gazette.com/pg/06256/721190-114.stm
http://en.wikipedia.org/wiki/Tetrachromacy
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
On the contrary. Go create a single-color or grayscale smooth one-dimensional gradient on a large-ish image (1024x1024 or so). It will show clear evidence of banding at 8 bits per channel, since there are only 256 color levels available.
This will be substantially reduced if everything were properly dithered, but in normal software and normal displays it is not.
How worth it is I don't know, but there is absolutely an easily detectable difference. How about testing your hypothesis before claiming you know what you're talking about, hmm? It's not exactly a difficult experiment to carry out.
To see billions of colors at the same time one only needs LSD technology...
how long until