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Madoc
09-11-2003, 02:08 AM
We're looking into stereo or even holographic rendering. We've had a look around but it's hard to tell how good the results from various devices are without going for a demonstration. Most stuff seems to involve glasses (about 800$ a pair) and stereo rendering (semi professional graphics hw only, right? ie Quadro, FireGL) through a 100Hz monitor or a special stereo projector.

The cost of the glasses could actually be a concern as we might expect to have large numbers of people viewing at the same time.

From what I've understood overlaying images and using simple colour filter glasses gives a noticeable loss of colour.

Anyone had experience with this sort of stuff and can recommend something?

knackered
09-11-2003, 06:20 AM
Synthagram?

mogumbo
09-11-2003, 06:27 AM
It all depends on your application. Shutter glasses usually give you the most flexibility. Stereo HMDs are also alright for some apps if you don't mind having one attached to your head. You can also do passive stereo; the polarized glasses are cheaper, but you need two projectors.
By the way, what do you mean by "holographic rendering"?

Madoc
09-11-2003, 07:22 AM
Originally posted by mogumbo:
By the way, what do you mean by "holographic rendering"?

Ehm... dunno. Well, something that don't require any kind of glasses or anything but can just be viewed. We've had clients asking for this. I've seen something of the sort years back and I've heard about all sorts of stuff since... Have no idea what's actually available or how it works.
Perhaps "hologram" is more specific and I'm misusing the term?

Madoc
09-11-2003, 07:31 AM
Originally posted by knackered:
Synthagram?

Ever seen one?
StereoGraphics seems to anyway be the top supplier so perhaps I should just go give them a visit.

mogumbo
09-11-2003, 07:50 AM
I think the usual term for this is "autostereographic display." The Synthagram by Stereographics Corp that Knackered mentioned is one of them. I think these displays usually rely on interlacing many images together and viewing them through a filter that only allows one image to be seen from a certain angle. That way each of your eyes sees a different image. There may be other similar technologies, but I've never seen one that doesn't suffer a pretty severe loss in resolution.

Microfunguy
09-11-2003, 08:17 AM
Colour anaglyph using red/cyan glasses give a surprisingly good reproduction of colour.
Otherwise, quad-buffered stereo OpenGL using inexpensive cordless (infra-red) shutter glasses is preferred. There is no resolution loss.

StereoPhoto Maker http://www3.zero.ad.jp/esuto/ supports both the above (and other methods) and gives details of how you can 'patch' GeForce cards to a 'Quadro.
You cannot patch the GeForceFX for stereo OpenGL.

I use inexpensive (70) E-Dimensional infra-red shutter glasses for stills and movies.
StereoPhoto Maker allows you to adjust images, alter stereo-depth, build slide-shows with sound, send a stereo image to a mobile phone, auto-scroll stereo panoramas, etc., etc.

The price ...... free !

(Yes I have a vested interest, I liked the programme so much I volunteered to write the English-language documentation).

David Sykes

Microfunguy
09-11-2003, 08:29 AM
I forgot to add, you do not have to use quad-buffered stereo OpenGL.

StereoPhoto Maker also works with any graphic card using NVidia chipset and which has the stereo driver installed.

However, OpenGL is the only method that supports stereo in a window.
You can start-up multiple instances of SPM and display many independent stereo windows.

David Sykes

Adrian
09-11-2003, 10:20 AM
I worked on a simulation two years ago using stereo LCD glasses from Cybermind.

The biggest problem was the lack of FOV, I just checked their website and they still have a diagonal FOV of only 31 degrees(for the reasonably priced glasses). As someone else said to me, it's like sitting at the back of a cinema.

Quad buffering didn't work correctly on most driver versions for the quadro. In fact I only ever found one driver version where it worked flawlessly, this issue appeared to be system dependent though. Search this board for posts I and one other person made about this.

[This message has been edited by Adrian (edited 09-11-2003).]

sufficient
09-12-2003, 02:46 AM
Well the Synthagram is an impressive beast - we have one in the office.
Resolution is pretty good these days (3840x2400, but the res is split into 3 on both axis because of the 9 viewpoints encoded in each 'pixel' (3x3 square), so that's...err, 1280x800).
It means rendering the scene 9 times, and you lose the stencil buffer (because stencil is used as a mask for each view, unless you render into a texture first).
It's just a crazy thing to see - realtime animated holograms.
However, 9 viewpoints is a little low in my opinion, but it gives a very convincing depth effect so long as you don't move your head around too much! http://www.stereographics.com/products/synthagram/synthagram.htm

Resellers (whom I happen to work for - but I am of course objective): http://www.vrweb.com
VP Products->Stereo Viewing->Stereo Graphics->Synthagram

Madoc
09-12-2003, 07:04 AM
Originally posted by Microfunguy:
Colour anaglyph using red/cyan glasses give a surprisingly good reproduction of colour.

This sounds pretty interesting for being a fast, cheap and portable solution. I've been trying to verify the validity of it but I've yet to get hold of some colour filters for the eyes.
Do you know how I can get some info on implementing this?

I never mentioned this but this is supposed to all work with our OpenGL graphics engine. Wouldn't want any software beyond device drivers involved really.

Microfunguy
09-12-2003, 09:53 AM
The information below was posted in response to some comments I made in Yahoo Photo3D forum regarding filters for colour anaglyphs.
It makes the useful point that it is the combination of the filter and display characteristics that determines the final colour reproduction (and your eye of course).
So you may want to experiment and tweak the intensities of red and cyan while viewing with certain Lee filters.
If you wish, you can do the colour tweaking in StereoPhoto Maker, otherwise it is part of your programme.
Lee filters come in large sheets and are very inexpensive for experimenting.
You could decide to rely on the mass-produced glasses and tweak your colours to suit.

David Sykes


--------------------------------------------
We get many requests for different combinations of Lee Filter
colors depending on the viewing application. Some combinations
are better for print and some for viewing online. We also adjust
filter colors to how different papers take printing ink. You can
try from 166, 164, 024, 182 in the reds and 354, 116, 115 in the
blue/cyan ranges. We manufacture a standard combination of
red/blue and red/cyan which we always stock and custom print. We
will also build any specific combinations of filter colors into
glasses and viewers.

Mark
Rainbow Symphony, Inc. http://www.rainbowsymphony.com
Ph# 818-708-8400
Fax# 818-708-8470
Quality Paper Eyewear and Specialty Optics

V-man
09-12-2003, 10:21 AM
Originally posted by Madoc:
Ehm... dunno. Well, something that don't require any kind of glasses or anything but can just be viewed. We've had clients asking for this. I've seen something of the sort years back and I've heard about all sorts of stuff since... Have no idea what's actually available or how it works.
Perhaps "hologram" is more specific and I'm misusing the term?

holograms is an old thing and it started out being monochromatic and beeing static on glass.

We have a local planeterium here and there is a spacial cinema room with moving floor and color + animated holograms.
It`s really amazing but I don`t know how it`s done. I think it is projected on glass.

... So the technology does exist.

john
09-17-2003, 12:39 AM
http://www.io2technology.com/

Zengar
09-17-2003, 01:02 AM
Well, old good SF films appearto be reality!
Amusing!