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active 3dtv and graphics card combo that works w/ opengl QBS
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Author:  flitcher [ 20 Sep 2012, 14:44 ]
Post subject:  active 3dtv and graphics card combo that works w/ opengl QBS

I have a stereoscopic visualization I've written in C++ using opengl that I want to display on a 3dtv. Nvidia's only solution for me required getting a DLP and 3dvision. I wasn't impressed so I called up AMD. They said that the higher end fireproV series could do this. I've purchased a firepro V8800, only to find out that it can not send a 3d image to a 3dtv in a format that the tv will recognize. I'm now told by AMD tech support that this is because the V8800 has DPv1.1 outputs, not DPv1.2, and so it doesn't have the needed resolution to do stereoscopic 1080p60 which is what most active 3dtvs require as an input. I also tried autodesk's maya, just to see if it would work (to make sure my program wasn't the problem), and got the same result: that is two images that appear to be overlayed on the screen (although my guess is that they are left and right eye images alternating at 30hz, and therefore appear to be overlayed).
Does anyone know of a success story with any graphics card with any active 3dtv for programs using opengl quad buffered stereo (e.g. maya)? Now, I'm being told by AMD that I need to get a fireproW series because it has DPv1.2 outputs. I can't afford to keep sinking $1K+ into solutions that don't work.

Author:  Bloody [ 20 Sep 2012, 15:06 ]
Post subject:  Re: active 3dtv and graphics card combo that works w/ opengl

I'd suggest that you stop listening to what AMD is telling you, as the person who is giving you these responses clearly does not know what he/she is talking about... he has just heard the keywords OpenFL and 3D and has assumed something. AMD's professional level graphics cards as well as Nvidia's Quadros both support OpenGL Quad Buffer mode for Stereo 3D, however this is not intended to work with 3D HDTV's as most of the 3D-capable 3D TV sets rely on HDMI 1.4 frame packaging method for receiving 3D input. This 3D output method is not supported by professional applications yet under OpenGL, but both AMD and Nvidia support it on their consumer level GPUs, though it only works on Direct3D and not OpenGL, and most 3D HDTVs also do offer support for Side by Side and Over/Under input methods for 3D and fewer models also come with Row Interleaved, DLP Checkerboard and others as well. So here comes the problem OpenGL 3D output and 3D HDTVs using HDMI 1.4 frame packaging are kind of incompatible, you either need to add support for something like Side by Side output (lower horizontal resolution) in your app and manually activate the Side by Side 3D input mode from the 3D HDTV set or rewrite your program using Direct3D. Alternative option in to go for a passive 3D HDTV where you can directly feed it with Row Interleaved image without having to rely on HDMI 1.4 at all, but this means reduced vertical resolution in stereo 3D mode.

Regarding DisplayPort 1.1 or 1.2 it does not matter at all when talking about 3D HDTVs as there you don't get DP interface, but HDMI 1.4 and both can DisplayPort revisions provide enough bandwidth for the needs of the HDMI. Also 3D HDTV as of the moment do not support 1080p 60Hz 3D mode, you are limited to 720p 50/60Hz 3D mode or 1080p 24Hz 3D mode when using full resolution 3D over HDMI 1.4 interface in frame packaging mode. Using an alternative mode such as Side by Side for example you cans end 1080p 60Hz signal, but this will lead to getting lower horizontal resolution in 3D mode, the same applies when using passive 3D HDTV in Row Interleaved mode where the halved resolution is vertical.

Have you considered going for a bigger active 3D monitor that uses frame sequential input for 3D as an alternative to 3D HDTV? This way you can get 1080p 60Hz 3D mode at full resolution and it will work with Quad Buffer OpenGL stereo 3D mode...

Author:  flitcher [ 21 Sep 2012, 00:49 ]
Post subject:  Re: active 3dtv and graphics card combo that works w/ opengl

Thank you - very enlightening. After the firepro v8800 didn't work out as promised, I've been very skeptical of anything I've been told by AMD. I did get this bit of information from them today: that a 3dtv + firepro card will work only if I purchase as 3dtv that supports fast hdmi, meaning it should support 300MHz HDMI. From what I've found online, fast hdmi is a term amd made up, and (although I'm unsure) this seems to be running a 3dtv like a computer monitor. I haven't had any luck finding a 3dtv that supports fast hdmi, or at finding a 3d monitor that would be large enough for the my requirements (>52").

If I'm understanding you right, I have these options:
1) Do side by side or top/bottom packing in my code and force the tv into side by side or top/bottom mode
2) Do the same thing for a passive tv using row interleaved packing
3) Rewrite the code using direct3d
4) Get a really big 3d monitor

Unfortunately I'm no programming guru, so I'm not sure #1 or 2 can be easily done. Hopefully directx is easy to learn...

BTW, you say that max refresh rate is 24Hz at 1080p - I thought newer 3dtvs came with 1080p@120Hz and @240Hz

Author:  Bloody [ 21 Sep 2012, 08:18 ]
Post subject:  Re: active 3dtv and graphics card combo that works w/ opengl

Well, as far as I know there are still no 3D HDTVs available on the market that do come with the new higher bandwidth HDMI chips, so even if the card supports it and you cannot buy a TV set that does it is pointless. Not to mention that you'd still need to have software support to output in the right mode using OpenGL QB.

You've got the few major options you have right. Rewriting the code using Direct3D won't be easy if you haven't programmed using it until now. The biggest 3D-capable monitors compatible with AMD/Nvidia stereo 3D solutions are 27-inch in size, so much smaller than what you need.

The actual input that you send to the 3D HDTV in stereo 3D mode over the HDMI 1.4 interface is limited to 24Hz in 1080p 3D mode, in 2D mode you can send 1080p 60Hz signal. The rest is just marketing and it refers to various internal algorithms that the TV set has for processing the lower framerate input in order to make fast moving objects to look clearer and sharper when displayed on the screen.

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