Stereoscopic Multiplexer Installation Guide

Stereoscopic Multiplexer Installation Guide

This guide explains how to use the Stereoscopic Multiplexer driver together with Stereoscopic Player. Make sure you have the newest player version installed. Once the driver is configured properly, use a capture application of your choice to record 3D video.

First, make sure that both cameras are connected to your PC and work properly. Verify that the cameras work simultaneously at the desired resolution by running two instances of any video capture application and previewing both videos. If you use Stereoscopic Player for this tests, ignore the error message during startup that the video library is already locked by the first instance and click File->Live Video to open a device.

Important: When using DV devices, it is necessary to connect them to separate Firewire controllers. Using two jacks on the same controller does not work! If you use Firewire webcams or industrial cameras according to the 1394 Trade Association's Digital Camera Specification, it depends on the resolution and frame rate whether two controllers are necessary or not. Click here for an overview of bandwidth requirements for different video modes.

When you load the driver the first time (e.g. File->Live Video->Stereoscopic Multiplexer in Stereoscopic Player) , it will display a configuration dialog. Select left and right capture device and fill in the video format you want to use. It's very important to specify a format that is supported directly by both of your cameras. If the cameras support two or more of the following color spaces, use the one listed first:

YUY2 (YUV 4:2:2)
UYVY (YUV 4:2:2)
RGB 32 (RGB, 32 bits per pixel)
RGB 24 (RGB, 24 bits per pixel)

If non of the camera's color spaces are supported by the Stereoscopic Multiplexer, try RGB 24 or RGB 32 first. In this case, you must specify the camera's default resolution!

Usually, it's not necessary to enter a frame rate, Use default should work in any case. Enter a frame rate manually to force a frame rate which differs from the default (provided that the capture device supports this frame rate).

Click OK. If the message Could not load left/right capture device! appears, the device might be still in use by another application. Could not connect left/right capture device! means that the specified format is not supported by the camera. In this case, try another format (resolution and color space). You can access the configuration dialog at any time by clicking File->Format Properties in Stereoscopic Player. How to find out which formats are supported by the capture devices is explained in the troubleshooting guide.

Hint: The proper settings for DV devices are 720 x 576 pixel (PAL) or 720 x 480 pixel (NTSC). The recommended color space is YUY2. Typical webcam resolutions are 640 x 480 and 320 x 240, the color space depends on the camera (RGB 24 or RGB 32 are usually supported).

After Stereoscopic Multiplexer has been loaded successfully, you have to tell the player about the Multiplexer's output layout. It's side-by-side, so you have to choose, File->Layout->Side By Side, Right Image First. You should also set the aspect rate in the File->Aspect Ratio menu.

To adjust camera parameters or apply image processing functions, click File->Device Properties.


Processing: All functions offered on this tab are implemented in the Stereoscopic Multiplexer, activating them consumes additional CPU power. Gamma, Sharpness, White level, Black level and Convert to ITU-R BT.601 are only available if YUY2 or UYVY is being used. Convert to ITU-R BT.601 must be checked if the cameras deliver image data with luminance and chrominance values in the range between 0 to 255 instead of 16 to 235 (luminance) and 16 to 240 (chrominance). For examples, this applies to the Sony DFW-VL500 cameras we use (and probably other cameras from the DFW series, too). The flipping options allow to flip both left and right image horizontally and vertically.

Camera Control, Image Settings: These tab allow to adjust camera properties. It depends on your camera's features which properties are actually available.  The pages are being hidden if no property is supported at all. When adjusting the value, it is set on both cameras. Stereoscopic Multiplexer periodically checks if the left or right value has changed and copies it to the other camera. Checking the Auto option lets the camera choose this property automatically. The auto mode is only set on the left camera and the current value periodically copied to the right camera. If left and right values should not be synchronized, uncheck the Sync option. Sometimes, left and right images look different although the same property values were used on both cameras due to different calibration after production. In this case it is possible to apply correction functions to each property. If a correction function has been defined, you can uncheck Corr to temporarily disable it.

Quality: Displays number of processed and dropped frames.

Simultaneous Recording & Preview

Stereoscopic Player does not allow to record the video, whereas capture application do not offer a stereoscopic preview. Using GraphEdit, it is possible to get both! First you have to download and install some additional components:

GraphEdit: Part of the DirectX SDK, either February 2005 version + extras or older version.
Stereoscopic Player: Get here.
Video Codec: We will use the PICVideo MJPEG Compressor in this sample, but any other compressor capable of real-time encoding works, too. For best quality, we recommend the lossless Huffyuv codec, however, you'll need a fast hard disc or RAID array for high resolutions or frame rates.

Run GraphEdit and insert all necessary filters (Graph->Insert Filter) as shown in the following screenshot. The filter named Recording.avi is a File Writer filter.

Right-click on a filter and choose Filter Properties to open the filter's configuration dialog. Configure the Stereoscopic Multiplexer as described above, then configure the Stereo Transformation Filter: Select Side by Side, Right Image First and your preferred output method. If you choose an anaglyph method, you should disable Allow YUV connections to obtain best image quality (YUV mode uses 4:2:2 color subsampling). If you choose NVIDIA Stereo Driver, Quad Buffered OpenGL or an interlaced viewing method, you have to insert the NVIDIA Stereo Renderer, OpenGL Stereo Renderer or DirectX Stereo Renderer instead of the Video Renderer. Dual Output and Dual Output, StereoBright require the Stereo Transformation Filter's second output to be connected to an additional Video Renderer.

Next, configure the video compressor you have inserted. If you have chosen a Video for Windows codec, it's not possible to configure the codec within GraphEdit. If you connect an audio capture device to the second AVI Mux input, you have to configure the AVI Mux to use recording mode. It also displays the dropped frames count. After you have configured all filters, connect them as shown below. Connect the Stereoscopic Multiplexer first and then the other filters in downstream order. When you connect the Stereoscopic Multiplexer, it will automatically insert the two capture devices and connect its inputs.

Make sure Graph->Use Clock is checked. Use Graph->Play to run the graph.

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