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RGB to become RGBCMY
elgatozorbas writes "The basic color elements of television have not changed much since 1954; a half-century after RCA introduced the first color set, the RGB (red, green and blue) system used then still prevails. But Israeli company Genoa Color Technologies has broken the RGB barrier by adding one to three primary colors such as yellow, cyan and magenta, thus expanding - from 55 to 95 percent - the coverage of the visible color gamut. The promised result of this multi-primary color (MPC) technology is a television picture that, with its truer, more vibrant color and brighter image, looks more like cinema than video. Also covered in IEEE Spectrum."
I wouldn't. It's taken so long to get HDTV "standard" that it will take just as long to get this new standard in. If everybody just upgraded to HDTV, they won't want to upgrade to this. These guys were about 5 years too late it seems :(
Sometimes the most mundane improvements can be the best. All the people who swear by HDTV will be SOL, because they'll have hi-res, but improperly colored, television/movies.
RGB is a set of orthogonal colors, and a linear combination of RGB can express any color in the universe. Similar comments apply to CMY.
Adding CMY to RGB to create RGBCMY does not buy you anything. Hence, the message starting this discussion thread is misleading.
Why is the television signal so poor in generating an image? The answer is unrelated to RGB. The answer is the the following. Prior to transmission, the analog RGB signal is converted into the digital YCbCr signal. (YCbCr is also an orthogonal set of colors.) Y, luma, is sampled at a reasonable rate, but the sampling system samples Cb and Cr at only half of the sampling rate for Y.
My guess is that RGBCMY is simply a clever attempt to use CMY to restore some of the samples of Cb and Cr that were discarded.
That's JUST what we need, more reasons to watch a box all day. I can look out my window and get all the colors all the time. And since I don't watch TV, time is something I've got 28-42 extra hours of every week.
Tell me you're not in denial - and I won't listen.
Stuff that matters.
Well, true they have to expand the gamut of existing RGB data artifically, but this is different from what you can do in photoshop. In this case the display can actually show more real colors than a conventional RGB display. Put the two monitors side-by-side, and you will be able to see colors on a RGBCMY monitor that simply cannot be reprodced on any normal RGB monitor. Have you ever taken a digital picture of a beautifully intense blue stain glass window, or some brightly colored flowers, and been disappointed when you got it home to see how bland the colors were on your monitor. The gamut captured by the camera is part of the problem, but even if it captured the colors perfectly, current monitors still couldn't display the results. These new wide gamut monitors should be able to do much better.
Having to "make up" the additional color data is just a temporary measure until content creation software and image acquisition hardware catches up to the gamuts possible with these new monitors.
I, for one, welcome our new RGBCMY masters.
The method with which you combine colors determines whether they're additive, not the colors themselves.
Remember: It's about emitting light versus absorbing light.
If you have three flashlights with thin plastic in front, one of cyan, magenta, and yellow... When you combine the beams, things will get brighter (of course... Three flashlights). That's because the method being used to create the light is an additive process.
If it were a subtractive process, then you'd be able to make a "flash dark".
Because printing is always a subtractive process (Paper starts white, and must be made darker), the CMY/K gamut is used. (Notice that these three colors are less "strong" than RGB, making them easier to control and combine for printing). In really advanced printing, you can get multitudes of colors, to reproduce more variations, or to get more accurate color (Because sometimes mixing CYM to get perfect tones isn't as effective as it could be).
Keep in mind: We use combinational color models, because we find them managable and convenient. However, these color models are not perfect, and cannot be. We won't ever have it perfect until we're able to serve up colors by frequency, and have them displayed accurately. Even high-quality film is limited by the chemicals used to make the film.
~D
This sig has been enciphered with a one-time pad. It could say almost anything.
No. This is just moronic marketing hype from people who should know better targeting people who don't.
First of all it's not a new idea - we looked into it at apple in the mid 80's as a way of getting more brightness out of LCDs. Using a CMYG pattern for example.
Second, a cursory glance at the CIE diagram teaches those who understand how it works that well placed RGB primaries cover almost the entire visible gamut (90% or so). There just isn't 20% left to add with a few more primaries, let alone 65%. That's not how vision works. (A cyan primary might add about 10%, but a yellow doesn't do much of anything and magenta just isn't a primary).
And third, neither video nor movies are color matched anyway. There's no "right" color for a tv program. It's what you want it to be. That's why NTSC stands for Never Twice the Same Color. Expanding the gamut is just like turning up the saturation on your TV. Is your saturation maxed? If so, you'd probably like a TV with a larger gamut (OK, it's not quite that simple, but video programming is targeted to the typical gamut of a TV, so the new technologies typically have to be turned down or they look a unnatural, as the article described. That is, if you really use the new gamut, it looks borked anyway, unless you like that sort of thing.)
If you've got crappy, unsaturated primaries, then adding more colors can expand the range, but at the expense of monumental complexity in the color math. Comon - getting color matching to work even marginally right with only three primaries is a task yet to be even partially achieved - how many of you have color calibrated monitors? And you want to add more primaries? Get a grip on the 3 you've got!
The press release does speak of a truth in subtractive color displays (like LCDs but not CRTs) that there is an intrinsic trade off between color purity (gamut) and brightness. Of course you can always use a brighter lightbulb/backlight... Or an alternative primary color technology like CRTs LEDs OLEDs Lasers... etc today. Large screen OLEDS would have a far better gamut than this crap anyway.
If you want to see amazing color look to laser displays or Sony's new reflective ribbon technology (that uses a laser as the source) with pure RGB primaries, there's no advantage to be had...
As for the technology being unique or special (not short bus special, though it is that) it's not. Your 5/6/7/etc. color inkjet printer does exactly the same thing. With reflective images (subtractive color) you don't really have primaries, you've got inks, and long ago people chose to print in RGB complement CMY (the K part is just because most inks suck and CMY all togehter would be grey, not black, so they added the black - sound familiar to the story? That's only about 100 years old). Anyway, looking back at our old CIE diagram we see that Cyan Magenta and Yellow inscribe a wee triangle even with fully saturated inks, so Epson chose to add a few more colors (and then more, and more) and figure out the color math behind the transformation from CRT RGB primaries (or CIE LAB) to CMYKC2Y2M2 etc. It works well with printers (Epson was actually copying Pantone's Hexachrome offset process, which itself is probably not the first).
It's an OK idea to improve the image quality of the color mixing functions used to filter incoming light for color cameras (typicaly CMYG, though some cameras now use RGB), but it's just silly with LCDs. If you're really a color fanatic you're probably using a CRT anyway.
As an aside, in the persuit of some research about 10 years ago I found a paper article presenting research in capturing archival images of paintings and other works of art, and seeking to eliminate all possible metamerism between the color mixing functions of the detector and the human visual system. The authors found that to do so required a 7 primary system. I haven't been able to find the article again and I'm not