werner@aecom.yu.edu (Craig Werner) (09/21/90)
Does anyone at this early date have any information on IBM's
new XGA standard.
I know that it has a top resolution of 1024x768 noninterlaced
at 70MHz (isn't this lower than VESA and the European standards by
a handful of megahertz) but I'd like to know its standard and maximum
RAM configuration, how many colors it supports on-screen at 1024
resolution, and whether it supports the so-called super-VGA standard of
800x600 (which somehow I'm not hopeful of, but I assume clone boards,
when they appear, will throw this in anyway).
--
Craig Werner (future MD/PhD, 5.5 years down, 2.5 to go)
werner@aecom.YU.EDU -- Albert Einstein College of Medicine
(1935-14E Eastchester Rd., Bronx NY 10461, 212-931-2517)
"It's hard to argue with someone who knows what he's talking about."phil@brahms.amd.com (Phil Ngai) (09/22/90)
In article <3015@aecom.yu.edu> werner@aecom.yu.edu (Craig Werner) writes: | I know that it has a top resolution of 1024x768 noninterlaced |at 70MHz (isn't this lower than VESA and the European standards by |a handful of megahertz) but I'd like to know its standard and maximum I think you mean 70 hz. The Europeans are looking for 72 hz, I think. |RAM configuration, how many colors it supports on-screen at 1024 According to PC Week, 32,000 colors. They also said it's 16-bit color. I don't really understand this. -- Phil Ngai, phil@amd.com {uunet,decwrl,ucbvax}!amdcad!phil Freedom is dead, long live privacy!
bmarsh@cod.NOSC.MIL (William C. Marsh) (09/25/90)
In article <1990Sep22.023059.13976@amd.com> phil@brahms.amd.com (Phil Ngai) writes: >|RAM configuration, how many colors it supports on-screen at 1024 > >According to PC Week, 32,000 colors. They also said it's 16-bit >color. I don't really understand this. I don't know about the XGA directly, the Targa-16 uses a 16 bit pixel, with 5 bits for red, green, and blue (and one extra bit, Targa uses for overlay). (15 bits = 32768 colors, but then you probably already knew that! ;-) I'm sure they are doing something similar. Bill -- Bill Marsh, Naval Ocean Systems Center, San Diego, CA {arpa,mil}net: bmarsh@cod.nosc.mil uucp: {ihnp4,akgua,decvax,dcdwest,ucbvax}!sdcsvax!nosc!bmarsh "If everything seems to be coming your way, you're probably in the wrong lane."
mra@srchtec.UUCP (Michael Almond) (09/25/90)
In article <2270@cod.NOSC.MIL> bmarsh@cod.nosc.mil.UUCP (William C. Marsh) writes: >In article <1990Sep22.023059.13976@amd.com> phil@brahms.amd.com (Phil Ngai) writes: >>|RAM configuration, how many colors it supports on-screen at 1024 >> >>According to PC Week, 32,000 colors. They also said it's 16-bit >>color. I don't really understand this. > >I don't know about the XGA directly, the Targa-16 uses a 16 bit pixel, with >5 bits for red, green, and blue (and one extra bit, Targa uses for overlay). >(15 bits = 32768 colors, but then you probably already knew that! ;-) I'm >sure they are doing something similar. > I also saw the article in PC Week. Does anyone know if/when any manufactures will have boards/monitors available? (I'm in the process of putting a PC together and was going to by a NEC 4D). --- Michael R. Almond mra@srchtec.uucp (registered) search technology, inc. gatech.edu!stiatl!srchtec!mra Atlanta, Georgia (404) 441-1457 (office)
pnl@hpfinote.HP.COM (Peter Lim) (09/26/90)
> > According to PC Week, 32,000 colors. They also said it's 16-bit > color. I don't really understand this. > I guess 32,000 is rounding off of 32,768 which is 15-bit. What is the other bit for ?? Regards, ## Life is fast enough as it is ........ Peter Lim. ## .... DON'T PUSH IT !! >>>-------, ########################################### : E-mail: plim@hpsgwg.HP.COM Snail-mail: Hewlett Packard Singapore, : Tel: (065)-279-2289 (ICDS, ICS) | Telnet: 520-2289 1150 Depot Road, __\@/__ ... also at: pnl@hpfipnl.HP.COM Singapore 0410. SPLAT ! #include <standard_disclaimer.hpp>
dhesi%cirrusl@oliveb.ATC.olivetti.com (Rahul Dhesi) (09/28/90)
In <1990Sep22.023059.13976@amd.com> phil@brahms.amd.com (Phil Ngai) writes: >According to PC Week, 32,000 colors. Ah, the old controversy erupts again. The human eye recognizes only a few basic colors (some say these are cyan, magenta, and green). 32,000 different hues, maybe, but not 32,000 colors. Maybe 5, if you include white and black. -- Rahul Dhesi <dhesi%cirrusl@oliveb.ATC.olivetti.com> UUCP: oliveb!cirrusl!dhesi
davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (10/01/90)
In article <35010020@hpfinote.HP.COM> pnl@hpfinote.HP.COM (Peter Lim) writes: | I guess 32,000 is rounding off of 32,768 which is 15-bit. What is | the other bit for ?? Sounds like 5 bits each for the RGB gun intensities, like the pallette of the VGA has 6 bits for each color, but you can only have 256 total on the VGA. Note that if my surmise is correct the max number of grey levels will only be 32, as opposed to 64 for the VGA. -- bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen) sysop *IX BBS and Public Access UNIX moderator of comp.binaries.ibm.pc and 80386 mailing list "Stupidity, like virtue, is its own reward" -me
mra@srchtec.UUCP (Michael Almond) (10/01/90)
In article <35010020@hpfinote.HP.COM> pnl@hpfinote.HP.COM (Peter Lim) writes: >> >> According to PC Week, 32,000 colors. They also said it's 16-bit >> color. I don't really understand this. >> >I guess 32,000 is rounding off of 32,768 which is 15-bit. What is >the other bit for ?? > In the article it mentions that the cards will be capable of 24-bit color, with enough memory on board. I don't know about the extra bit, parity checking or something. I know IBM is suppose to show this board at Fall Comdex (November?), but has anyone heard of other companies saying they will be offering boards? And most important, would a NEC 3D/4D work with the new boards? --- Michael R. Almond mra@srchtec.uucp (registered) search technology, inc. emory.edu!stiatl!srchtec!mra Atlanta, Georgia (404) 441-1457 (office)
kevinc@cs.athabascau.ca (Kevin Crocker) (10/06/90)
In article <2519@cirrusl.UUCP> dhesi%cirrusl@oliveb.ATC.olivetti.com (Rahul Dhesi) writes: >Ah, the old controversy erupts again. The human eye recognizes only >a few basic colors (some say these are cyan, magenta, and green). >32,000 different hues, maybe, but not 32,000 colors. Maybe 5, if >you include white and black. And I thought it was just my eyes that were bad! :-)))))) BTW, Rahul, are you still working on ZOO? Mail to you seems to bounce. This is about the only mail that bounces these days but it does get annoying. Kevin P.S. I have to add this because our systems seems to have been upgraded and I can no longer send shorter replies than copied text. -- Kevin "auric" Crocker Athabasca University UUCP: ...!{alberta,ncc}!atha!kevinc Inet: kevinc@cs.AthabascaU.CA
kevinc@cs.athabascau.ca (Kevin Crocker) (10/06/90)
In article <245@srchtec.UUCP> mra@srchtec.UUCP (Michael Almond) writes: >>> According to PC Week, 32,000 colors. They also said it's 16-bit >>> color. I don't really understand this. O.K. I guess I really don't understand what it is that we're talking about either. Are we saying that the monitor will be capable of displaying ~32,000 hues simultaneously or that there will be the capability of displaying 256 hues out of a pallette of ~32,000? This makes no sense as we already have 256 out of a pallette of 256K? If we are talking about ~32000 hues on screen then is there any evidence to show that the human eye can discern this level of sublety? Kevin -- Kevin "auric" Crocker Athabasca University UUCP: ...!{alberta,ncc}!atha!kevinc Inet: kevinc@cs.AthabascaU.CA
cramer@optilink.UUCP (Clayton Cramer) (10/09/90)
In article <339@aupair.cs.athabascau.ca>, kevinc@cs.athabascau.ca (Kevin Crocker) writes: > In article <245@srchtec.UUCP> mra@srchtec.UUCP (Michael Almond) writes: > >>> According to PC Week, 32,000 colors. They also said it's 16-bit > >>> color. I don't really understand this. > > If we are talking about ~32000 hues on screen then is there any > evidence to show that the human eye can discern this level of sublety? > > Kevin "auric" Crocker Athabasca University I read somewhere, many years ago, where I can doubtless not find it, that the human eye is capable of distinguishing about 10 million shades of color. (Presumably measured by taking two light sources of known frequency some number of Angstroms apart, and seeing how many people can distinguish them). This means that when you get to 24 bits of color information, there is no point in going any further. -- Clayton E. Cramer {pyramid,pixar,tekbspa}!optilink!cramer If "right of the people" in the Second Amendment doesn't refer to an individual right, what does it refer to in the First & Fourth Amendments? You must be kidding! No company would hold opinions like mine!
pnl@hpfinote.HP.COM (Peter Lim) (10/11/90)
Okay, Here's my 2 cents' worth .... > I read somewhere, many years ago, where I can doubtless not find > it, that the human eye is capable of distinguishing about 10 million > shades of color. (Presumably measured by taking two light sources > of known frequency some number of Angstroms apart, and seeing how > many people can distinguish them). > Another school of thinking says that human eye can differentiate thousands of colors but cannot appreciate it very well. Confused ? Basically, its like if you show a human a 1024 color screen and then show him a 24-bit (16 million) color screen; he will not be able to tell the difference. BUT, if you put the two screens side by side, he can tell the difference ! > This means that when you get to 24 bits of color information, there > is no point in going any further. > I pretty much believe that 256 colors is just about enough. Of course the more the merrier, may be 1024 ?? But I really believe that we need at least 16 bit (or 65536 colors) colors to really do nice display. Why ? Well, these days, we really want multiple Windows on screen each having their own 1024 palette or so. So, I think PC's 256 color standard is deficient. Mac's 24 bit colors is overkill but I don't mind if the display card is not too bloody expensive. Regards, ## Life is fast enough as it is ........ Peter Lim. ## .... DON'T PUSH IT !! >>>-------, ########################################### : E-mail: plim@hpsgwg.HP.COM Snail-mail: Hewlett Packard Singapore, : Tel: (065)-279-2289 (ICDS, ICS) | Telnet: 520-2289 1150 Depot Road, __\@/__ ... also at: pnl@hpfipnl.HP.COM Singapore 0410. SPLAT ! #include <standard_disclaimer.hpp>
tow@arisia.Xerox.COM (Rob Tow) (10/13/90)
In article <4591@optilink.UUCP> cramer@optilink.UUCP (Clayton Cramer) writes: >In article <339@aupair.cs.athabascau.ca>, kevinc@cs.athabascau.ca (Kevin Crocker) writes: >> In article <245@srchtec.UUCP> mra@srchtec.UUCP (Michael Almond) writes: >> >>> According to PC Week, 32,000 colors. They also said it's 16-bit >> >>> color. I don't really understand this. >> >> If we are talking about ~32000 hues on screen then is there any >> evidence to show that the human eye can discern this level of sublety? >> >> Kevin "auric" Crocker Athabasca University > >I read somewhere, many years ago, where I can doubtless not find >it, that the human eye is capable of distinguishing about 10 million >shades of color. (Presumably measured by taking two light sources >of known frequency some number of Angstroms apart, and seeing how >many people can distinguish them). > >This means that when you get to 24 bits of color information, there >is no point in going any further. > >-- >Clayton E. Cramer {pyramid,pixar,tekbspa}!optilink!cramer >If "right of the people" in the Second Amendment doesn't refer to an >individual right, what does it refer to in the First & Fourth Amendments? >You must be kidding! No company would hold opinions like mine! Actually, this is not true. We're talking my field here; I design color scanners, color correction systems, and work on the monitor to print problem, for Xerox. 24 bits is insufficient for more than one reason. The first thing to consider is that the dynamic range of the eye is not a simple function, and is not the same for each of the three (actually, four; did you know that under the right circumstances people can be tetrachromats? This is called *rod intrusion*) input channels (which may be equated with red, green, and blue sensation). Under good conditions, with a calibrated monitor, you can see banding in an 8 bit gray ramp. Also, the range of intensity that is expressed in that ramp does not cover the full range of intensity the eye can percieve; i.e., there are "whiter whites" that you can respond to. The situation gets even more fun with the addition of colors, as opposed to grays. Another fun complication is that the primaries used in video, print, etc., do not cover the full *gamut* of color vision. If you plot the gamut given by, say, the SMPTE phosphours on a CIE color chart you will get a triangle inside the full range of human vision. There are colors you can see perfectly well that no monitor can display. This gives rise to a whole host of interesting tradeoffs - do you clip colors to the hull of the gamut, or somehow map one gamut to another? We do *both* here, depending on the image and the device - for example, last year's SIGGRAPH proceedings cover had a gamut mapping applied to it from the video image to map it into the printer's gamut. Consider also that when you do this that you are squashing levels and will lose discernable differences. An important consideration from an artists view is perserving discernable differences even if there are hue shifts! ...these days I get somewhat exercised by the widespread use of the phrase "True Color" in reference to 24 bit displays; they are anything *but* true color. The sad truth is that very few people have much sophistication for color; it's rather like typography before 1984. --- Rob Tow Member Research Staff Electronic Document Lab Xerox PARC 3333 Coyote Hill Drive Palo Alto, CA 94304 (415)-494-4807