Sony HMZ-T1 HMD

[Kaminski]

Hi All,

We have ordered the hmz-t1 and are wondering if anybody has used it with Vizard yet?

The manual online does not seem very specific regarding video channels and I was wondering if there is anything special we need to do to prepare. Are there any modules that we need to import for specific settings? We have an nVidia video card with hdmi out.

thanks

[farshizzo]

We have been using the Sony HMD here in the office for the past few months, and it works fine with Vizard. It accepts both horizontal and vertical split stereo as input.

[Kaminski]

Glad to know that it works fine with Vizard, thanks. By horizontal split stereo do you mean a single channel of 2560 x 720? Or should my system automatically detect the HMD as 2 separate displays?

[farshizzo]

No, it is detected as a single display (1280 x 720). So you will lose half the resolution when viewing in stereo.

[Kaminski]

Stereo is only (640 x 720) or (1280 x 360) then? Does the image scale for the display's aspect ratio?

[farshizzo]

Yes, the image gets stretched, so you will have to manually specify the full aspect ratio in your script:viz.fov(50,1280.0 / 720.0)

[Kaminski]

Ok, thanks. I guess I'll see how it looks for myself.

[farshizzo]

I just tested a solution that allows viewing full resolution stereo on the Sony HMD. The HMD accepts the HDMI 3D Frame Packing format as input. Apparently, the nVidia Quadro 3D Vision drivers can automatically convert the quad buffer output of an OpenGL application into this 3D Frame Packing format.

Here are the steps I took to get it working.

If multiple displays are connected, make the Sony HMD the primary display. I experienced strange bugs with the driver if the Sony HMD was not the primary display.
Enable quad buffer stereo in the nVidia Control Panel, 3D Settings -> Manage 3D settings -> Stereo - Enable -> On
Enable 3D vision stereo in the nVidia Control Panel, Stereoscopic 3D -> Set up stereoscopic 3D and check Enable stereoscopic 3D. The Stereoscopic 3D display type field should display 3DTV Play.
In your Vizard script, pass the viz.QUAD_BUFFER and viz.HMD flags to viz.go and make the Sony HMD the fullscreen monitor. For example, if the HMD was connected as monitor 2, you would use the following code:
import viz
viz.window.setFullscreenMonitor(2)
viz.go(viz.QUAD_BUFFER | viz.HMD)
.
.
.

Make sure automatic 3D signal detection is enabled on the HMD, and it should automatically switch to 3D mode when you run your script.

Unfortunately, I'm not aware of a solution for full resolution stereo with GeForce GPUs.

[lmtree797]

I am trying to understand how does buffer work here. Please check my idea. The reason we need quad buffer for the sony HMZ is it packaging stereo information in one channel which is sent in SX/ST HMD in two channels alternatively. Double buffer is used for each eye. So it works well in SX HMD not Sony HMZ.

Besides, I have 2 questions in testing the new HMD. I don't have nvidia
3D video card supporting quad buffer so I just use half resolution in 2 side-byi-side splitted display. I use the "viz.go(viz.SETERO_HORZ)" and often find I need converge a lot to focus the 3D and the near part looks distorted. Should I change the disparity or not?

Also, I specify the aspect ratio as 1280/720 by viz.fov(), however, there seems no difference when I set the vertical FOV as 50 degrees or 22 degrees (the later is the physical vFOV by the specification). Why does the vertical FOV value not affect the display?

Thanks!