Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Displays

Seamless Video Walls 135

ahfoo writes "A company called Seamless Display is shopping around a new way of hiding the seams in video walls that mostly relies on modifiying video drivers to achieve its effects. According to their press release they hide the edges between monitors with a bit of plastic film and compress the video at the edges to produce a more or less seamless image. " Really bizarre, but it looks interesting.
This discussion has been archived. No new comments can be posted.

Seamless Video Walls

Comments Filter:
  • I can't believe it, and this is a in the first minute after the story became available (to non-subscribers, okay...). Mirror anybody ?
  • by Dr. Manhattan ( 29720 ) <sorceror171.gmail@com> on Tuesday September 02, 2003 @10:46AM (#6850657) Homepage
    ...that was mentioned [slashdot.org] on Slashdot.
    • by Anonymous Coward
      Doesn't sound like the same thing. The company in this article makes a video wall. VisualLabs tried to make large LCD display using smaller LCD panels. BTW, this company [rainbowdisplays.com] developed tiling LCD technology. They currently have a 37.5" display (due to technical and financial issues, the large monolithics have caught up) that is made from three 21.4" LCD tiles (two seems). The seems are not completly invisible. In all but low contrast (mainly black) images are the seems completly invisible.

      The way they do
  • ...modifiying video drivers to achieve its effects.

    That may be what that NVidia driver benchmark scandal was all about :)

  • by Brahmastra ( 685988 ) on Tuesday September 02, 2003 @10:48AM (#6850683)
    The best application for consumers looks like the folding LCD displays. It would be great to have handhelds with a folding screen without a perceptible seam. Finally it won't suck to play games on handhelds.
  • Rear Projection (Score:4, Interesting)

    by jhines0042 ( 184217 ) on Tuesday September 02, 2003 @10:48AM (#6850689) Journal
    Wouldn't a video wall be better served by having several rear projectors that line up perfectly rather than trying to eliminate the frame of a CRT?

    It seems to me that with a good jig and a consistent set of projectors, and some good use of mirrors if depth is a problem, that you should be able to get a seemless image with very little work.
    • Re:Rear Projection (Score:3, Interesting)

      by Sphere1952 ( 231666 )
      You've got an extra room to devote to the task?

      I think computing paint would better serve the purpose. When will I be able to just paint a monitor onto my wall? (And I bet the fumes will be carinogenic.)
      • Well for that you would need a bucket of clear nano-paint and a team of nano-ants to re-arrange the paint once applied. You also need a nano-bewolf cluster to coordinate the millions of ants (yes, nano power stations will soon be a consumer commoditie).

        I already got my nano-brain!
    • Re:Rear Projection (Score:4, Interesting)

      by CaptBubba ( 696284 ) on Tuesday September 02, 2003 @10:59AM (#6850807)
      They wouldn't have to even line them up exactly.

      I saw a demonstration using a beowulf cluster (well, part of one) that was rendering a moving 3-d CAD model. They just threw the projectors so they were somewhat aligned, used a webcam and had one of the nodes look at the overlap and correct for the projector's misalignment in real time. ~20 other CPUs were doing the rendering, but it only took one to make the display come out right. I would imagine the same thing could be done for a rear-projection screen. As long as the projectors didn't get jostled after being observed by the computer it should work fine.

      • Clemson's Beowulf group is currently working on this exact topic, except you have ~7:1 fan out on the graphics nodes for rendering, IE, you have 7 computers rendering, sending the frame over 10/100 to the switch which has 1gig to the display node that outputs it.

        It looks pretty sweet and they're getting there on real time graphics. All the projectors were just put back behind there on a rack (24 I think) and software + webcam is used to align and create a striaght and hopefully soon, color accurate picture
        • Interesting that you should mention Clemson, since I also know that they use a similar (though not exactly the same) setup for the driving lab in the Psych Department. They don't have them clustered quite the same, but essentially you have a control box (for the steering and pedals) connected to a relay, which converts the signal to 10/100, which then runs the signal out to 4 different computers that each run one screen for the "car". These are all linux boxes, and there is a final box running windows tha
        • We have a winner.

          I saw this on a tour of the Computer Science department at Clemson, where I go t' get meself learned. I didn't know the exact way they had the boxes networked, so I didn't say instead of spreading false info.

          The only issue I saw was the brightness of the overlapping areas was higher than the non-overlapping areas simply because two projectors were displaying the same thing in the same area, as noted by Dirk.Reiners below.

      • Re:Rear Projection (Score:5, Insightful)

        by Dirk.Reiners ( 89339 ) on Tuesday September 02, 2003 @11:37AM (#6851091)
        There are a bunch of these around, the keyword to look for is tiled display. It's been an active topic in the computer graphics and virtual reality community for the last couple years, and people have been building different sizes and using different alignment methods. The biggest ones I know are the NCSA 40 node and our 48 node system. Most of them are mono, there are two stereo-capable systems, one in Boston, the other one is ours.

        The problem with the "rough alignment, use computer vision to sort it out" approach is the overlap area. Current projectors have a pretty sucky contrast (black to white) ratio. In the overlap areas all the blacks are added together, so the actual black you get is already pretty bright and there's nothing you can do about it. That's why we decided to go the hard route and do exact alignment. It's hard, but it's doable, and the results are pretty cool.

        The presented method avoids that problem by design, so that's what makes it interesting, IMHO. Beside the fact that it doesn't need a separate air condition and 3 m back-projection space...

        • If you could futz with the projector itself, you
          could have it project a few reference dots in an
          invisible part of the spectrum, then use an
          e.g. infrared camera to pick those out and align
          by that.
      • Ah, this guy just got +5 Insightful because he managed to sneak a Beowulf cluster reference in...
      • I saw a demonstration using a beowulf cluster (well, part of one)

        From a glossary [phys.uu.nl], I get:

        "Cluster of PCs or workstations with a private network to connect them. Initially the name was used for do-it-yourself collections of PCs mostly connected by Ethernet and running Linux to have a cheap alternative for "integrated" parallel machines. Presently, the definition is wider including high-speed switched networks, fast RISC-based processors and complete vendor-preconfigured rack-mounted systems with either
        • Okay, the entire group of machines is the cluster. If a subset of those machines are used to perform some task, they can rightly be referred to as a Beowulf cluster on their own. However they are stil "part of" the larger cluster. This is likely what the grandparent poster was referring to.

          Similarly, if I have a hundred people, that's a crowd. If I take 50 of those people, they are still a crowd, however they are also a subset, and hence a "part of", the original crowd.
    • Re:Rear Projection (Score:3, Informative)

      by Aidtopia ( 667351 )

      This is a standard multi-image trick. It works with front or rear projection. To get the images truly seamless, you overlap the projection areas (anywhere from 10 to 50%) and use a grayscale gradient mask to blend the overlapping areas. This technique was perfected with those zillion-projector slide shows from the '80s.

      The trick lives on today with video projections. Dataton has a product (Watchout) which does it in real time with a network of computers. And, as another poster pointed out, aligning t

    • You get more pixels with multiple monitors.
    • slashdot did a story [slashdot.org] a while back on Sandia's 20-Million-Pixel, 130-Square-Foot Screen [sandia.gov].

      it sure would be fun to build one of those! unfortunately it would also be very expensive...

      (i'd be pretty happy "just" with two XGA projectors, in a dual-head config. i've borrowed one from work and brought it home to show DVDs on the wall, which works well, but i've got room for twice as wide a screen....)
  • Interesting, but (Score:3, Insightful)

    by Oculus Habent ( 562837 ) * <oculus.habent@g m a il.com> on Tuesday September 02, 2003 @10:48AM (#6850695) Journal
    Having to change the video drivers to "compress the edges" seems like a messy task. I don't see any information about control software that lets you choose which edges are compressed, either.

    A little sparse on technical detail, though that is somewhat expected... I want to know where the "compressed image" it talks about comes from. Does it create additional "virtual pixels" that cover the gap, and then mash them into the few on the edges?
    • I read about this in another article (can't remember where though) that it compresses the edges (10-20 pixels) with a discrete cosine transformation (as in jpeg). They could use huffmann, but that would make the edges jagged, and the screen wouldn't be seamless anymore.


      The reason that they have to do this in the driver is that they have to hit low level to get decent speeds (windows display drivers can hit the hardware directly, contrary to most other windows drivers).

    • It sounds like the plastic is used to optically stretch the pixels at the edge of the screen over the seam; the software then modifies the image passed out to allow for these unusual shaped pixels.
  • Psssh.... (Score:4, Funny)

    by JoeLinux ( 20366 ) <joelinux@ g m a i l . c om> on Tuesday September 02, 2003 @10:50AM (#6850709)
    Big deal. I'm wating for the DirectBrainX from Microsoft. Just plug directly into the base of your skull and watch your will to live drain away.

    Blue screens now resulting in total loss of bowel functions!

    *sniff* I'm getting misty just thinking about it.
  • OLEDs are almost there, they are already being used in small portable devices (cameras and phones). They can be scaled without the fabrication issues that hit CRTs and LCDs. There is a good chance that OLED screens will be the first consumer-ready wall screen system (the current best of breed being the projector).

    But this looks fun, and it may be a good stopgap. I'm wondering whether it can be used to build (for instance) large LCD monitors for PCs...? I once had a portable that used two B&W LCDs to achieve a larger display area, but I've never seen this done with color LCDs.
    • after reading the pieces on CDR's which use organic dyes, and the organic dyes don't last beacuse they break down, I wonder about the long term viability of Oled's. Aren't those organic components subject to the same rules of degradation as the organic dyes?
      • The fantasy is that OLED will be so cheap to produce, it wont matter to you. Your roll-up wall-sized screen will be priced like drapery fabric at the local craft store.

        So when it fades, you'll be able to replace it cheaply, just like replacing the faded Pink Floyd poster from your college days.

        This, of course, has been the promise of most new tech. Super-cheap and disposable. We'll see.
        • Your roll-up wall-sized screen will be priced like drapery fabric at the local craft store.

          It's not hard to spend thousands of dollars on drapes, if you want good (quality materials, non-white-trash styles) drapes. Add features like heat-reflecting fabric or motorization and it only goes up..

          Or does that mean that if I want a big screen I have a choice of thousands of dollars for a good one, or $50 for a shit one?
      • They use organic polymers - dyes are organic. Everything fades. Your laptop will fade. OLEDs sometime do this faster, sometimes slower.
    • OLEDs have some time to go. I have seen some of the new kodak ones and they have a small issue. They can't do red or a deep blue, infact the red is orange. I load up true red from VESA standards, and I see an off Orange. The blue is pretty good, but violet is impossible for now. This doesn't began to describe aging. The Kodak camera that uses OLEDs has a life span of 1000 hours. That is total. The individual colors age differantly as well. So what was blue green will shift over time to either side. This is
      • The joys of being color blind, i don't care if the Red looks orange or if the colors fade.....:)
        • You will when the whole thing darkens. OLEDs have their white put out by three color subpixels and the aging will make the total brightness decrease, a lot.
  • by blankinthefill ( 665181 ) <blachanc&gmail,com> on Tuesday September 02, 2003 @10:54AM (#6850747) Journal
    What does this mean for the MS Flight Simulator Groupie?!? Are we going to be getting entire "flight rooms" now? AHHHHH!!!!
  • One word:

    PORN!

  • Hidden page (Score:2, Funny)

    by jarda ( 635462 )
    Obviously, now they have compressed and hidden their whole page before slashdot crowd. So, it seems to be working.
    • Which always begs the question do the editors give the people a heads up a slashdoting is a moment away?

      Seems like potential lawsuit to me :-)

      Uh oh... I just gave "them" an idea.... noooo!

      Tom
    • Actually, when I loaded their page I saw a perfect demonstration of their seamless image technology... Right under the header there was a large image box with absolutely no seams, bluryness, or other aborations(sp?). In fact the only thing out of place was the small broken image icon in the top left corner... otherwise it was one beautiful seamless image of a typical winter storm in Saskatchewan, Canada.

      Merlin.

  • It looks to me like they may have used one of the desktop models [panoramtech.com] from Panoram Technologies [panoramtech.com].
  • Try draper as well (Score:5, Interesting)

    by Stonent1 ( 594886 ) <stonentNO@SPAMstonent.pointclark.net> on Tuesday September 02, 2003 @10:56AM (#6850775) Journal
    www.draper.com [draper.com] Back when I installed Air Traffic Control simulators we used Draper screens. I was looking at the Draper site and they said they had seemless displays and this was about a year ago. We could get pretty seemless with the large screens that we had.
  • Mirror (Score:4, Informative)

    by Talia Starhawke ( 650311 ) <{talia_starhawk} {at} {yahoo.com}> on Tuesday September 02, 2003 @10:59AM (#6850801) Homepage Journal
    Here's a Press Release [ox.ac.uk]...
  • Technology.... (Score:4, Interesting)

    by $exyNerdie ( 683214 ) on Tuesday September 02, 2003 @11:01AM (#6850823) Homepage Journal

    Well, it seems that they use a lens coating to correct image corners (could be affected by wear and tear). I thought it was ONLY a software based change in display drivers.

  • by Animats ( 122034 ) on Tuesday September 02, 2003 @11:11AM (#6850896) Homepage
    This is a plausible, although not great, idea. Optically expanding a display screen a bit to merge the edges have been tried before. It's possible to expand the whole image without parallax using a big fibre optic plate, but that approach is heavy and expensive. This approach apparently only messes with the edges, squeezing them digitally to compensate for an optical device (probably a plastic Fresnel lens) that expands them to cover the gap. The compressed region also needs an intensity boost, since fewer pixels are filling more area. From the pictures, they didn't do that, so there's a dim line at the joint.

    We'll have to see how good it is, and whether it looks any good from an off-axis viewpoint.

    "Doctor, I want a system where everything comes out of one hole." Mike Todd, producer, to the head of American Optical, discussing wide-screen projection.

    • The compressed region also needs an intensity boost, since fewer pixels are filling more area. From the pictures, they didn't do that, so there's a dim line at the joint.

      The problem with that is you then "waste" the 99% of the screen brightness capability for non-edge pixels. Either that, have special pixels for the edges, but that introduces visual differences caused by different manufacturing processes for edge versus non-edge pixels.

      For example, lets assume uniform pixel types. Lets say the max pixe
  • by FreeLinux ( 555387 ) on Tuesday September 02, 2003 @11:12AM (#6850904)
    Here [optics.org] is another atricle about it that includes a picture of the display. This one isn't Slashdotted.
  • I would think the change would make MORE sense in the firmware of the hardware, than the drivers.

    Customizations of drivers for specific hardware almost ALWAYS lead to bloated drivers that cause compatibility issues with other devices.
  • How do I mirror a website? I'm a subscriber, and managed to nab some photos - now what? Is there a fast way to do it and throw it on my hosted server? With a mac?

    Or just gimme a link and I'll figure it out. I'd love to mirror stuff when I catch it, but I need to be beaten with the cluestick.

  • by johnthorensen ( 539527 ) on Tuesday September 02, 2003 @11:18AM (#6850941)
    Now if only they could apply this technology to the scars from my woman's boob job :)

    -JT
  • I can totally see this being integrated in massive MISSPs where monitoring large volumes of incoming intrusion alerts and data on enterprise size SIMS (security information and management systems requires plenty of shuffling on a large visible desktop.

    In a way very Minority Report-ish.
  • Now only if (Score:4, Funny)

    by Bruha ( 412869 ) on Tuesday September 02, 2003 @11:29AM (#6851021) Homepage Journal
    They put in a few more dollars on that webserver and their slashdotting would of been seamless.
  • Great Stories (Score:1, Offtopic)

    by PetoskeyGuy ( 648788 )
    A little off-topic, but this reminds me of Fahrenheit 451 by Ray Bradbury. He mentions similar things in several of his other books of short stories including The Painted Man. It's not central to the stories, but I would recommend any of his books.
    • Funny, because Fahrenheit 451 was the first thing I thought when I read the title of the article :)

      You're right, he does describe video walls. The movie only had a plasma screen though :(
  • A leetle Mirror (Score:4, Informative)

    by teamhasnoi ( 554944 ) * <teamhasnoi@yahoo.cLIONom minus cat> on Tuesday September 02, 2003 @11:44AM (#6851151) Journal
    Here's one page with some pics [theschmoejoes.com].

    And the mostly content free first page [theschmoejoes.com].

    This will be a good test of my provider :)

  • in Calgary already did that scam and Zelit, the main culprit, ran off to central Europe...
  • "more or less seamless"? Either a display has seams or it doesn't. Kinda like saying "more or less pregnant!" Slashdot could use more editorial control and less hype.

    (And, as others have pointed out, why not just use rear projection for video walls? FAR less expensive than LCD's. But it could be useful for desktops/portables...)
  • by green pizza ( 159161 ) on Tuesday September 02, 2003 @12:08PM (#6851320) Homepage
    I've seen SGI and Barco (the projector company) do this for over a decade on their massive multi-projector screens. (As have Panoram and others...) It's a combination of software (generally image overlap) and hardware (soft edges) that produces an invisible seam. With modern high-dollar projectors there isn't even a noticable difference in brightness anywhere on the screen.

    Keep in mind that these sort of professional "reality centers" generally have very precise and predictable optics, these aren't the sort of projects you can buy at Staples or Frys. Cheaply made LCD projectors had a nasty habit of discoloring and changing their output look over time, especially when run for several hours every day. DLP has made a life a lot easier, but the cheap projectors still can't handle continuous use. Shop around and talk to the experts before you plunk a bunch of money down on an array of projectors.
  • It might be interesting to note that the very first PC laptop (not from IBM but from Data General, their "PC-1") was made at a time they couldn't get even full size mono LCD displays. The PC-1 display was actually made of 4 smaller LCD displays, specially made so the driver electronics were at one end and cut so closely that the pixels joined properly without showing a visable seam (although you could see it if you looked at the display while not in use rather than at the text or graphics) and without extra
    • It might be interesting to note that the very first PC laptop (not from IBM but from Data General, their "PC-1") was made at a time they couldn't get even full size mono LCD displays. The PC-1 display...

      Do you mean the DG1? If so, I can vouch for the invisible seams... because I've used a DG1 and never noticed that the display was made up of multiple panels!!
      • Yea, I think I remembered the name wrong, DG1 sounds right. It was an early mono PC laptop, a nonstandard serial interface (the IBM design was so poor they changed it, but being non-standard caused it's own problems) but otherwise an amazing device for a first laptop. If you stll have it dust it off and look closely at the screen, you should see the 4 LCD displays. I don't know if this design was used for the full production run of the laptop, but it was certainly there on the early ones I saw. Very hard t
  • Woo, now I can add a Linear Cockpit System [geocities.com] to my Gundam [geocities.com].

    ...Or not.
  • like you can still see the lines in between the screens.
  • Damn, I want one...

    Anyone need a kidney?
  • After seeing a picture of how it works [seamlessdisplay.com] I'm not especially impressed. Seems to be nothing more than a glass lens and a video driver to "compress" the edges of the displays.
  • Hi,

    what makes you realize that there are edges behind the lenses, is the fact, that the picture is somewhat darker in that areas. But the graphic driver has to be patched anyway. I wonder whether it isn't possible to eliminate the darkness by simply brightening the picture in the areas where the lenses are used.

    darkcookie.

"Someone's been mean to you! Tell me who it is, so I can punch him tastefully." -- Ralph Bakshi's Mighty Mouse

Working...