Stereoscopic Multiplexer User Guide


Stereoscopic Multiplexer Configuration

Since versions 0.5, Stereoscopic Multiplexer includes an easy-to-use configuration tool. Its wizard allows you to configure the Stereoscopic Multiplexer with a few clicks. If you are still using an older version, we strongly recommend to upgrade. The upgrade is free for registered users of all previous versions. To enter your product key, click Help>Enter Product Key in the Stereoscopic Multiplexer Configurator. The unregistered version is fully functional, but will watermark all captured content.

First of all, make sure that both capture devices (cameras, capture cards, ...) are ready for operation.

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.
USB 2.0 cameras also require separate USB 2.0 controller, depending on the resolution and frame rate. Some cameras require separate controllers even at lowest resolutions.

Click Start>All Programs>Stereoscopic Multiplexer>Stereoscopic Multiplexer to run the Stereoscopic Multiplexer Configurator. If you are using the Stereoscopic Multiplexer for the first time, it will open the configuration wizard automatically, else click Driver>Configuration Wizard.

Stereoscopic Multiplexer capture device selection

Select left and right capture device and click Next. Make sure you do not select the same item as left and right capture device (because their names are usually the same). If your devices do not show up, make sure that

  • they are connected to the PC
  • they are turned on
  • their drivers are installed

Stereoscopic Multiplexer capture format selection

The list of capture formats includes only items which are actually available on both capture devices. If the Stereoscopic Multiplexer Configurator cannot find any compatible format, it will still offer RGB 32 at the left device's default resolution. It is very likely that there is a decoder available which converts the unsupported format to RGB 32, so that in such cases the suggested format will work as well.

Click the Test left device and the Test right device buttons to test the devices using the selected format. In case left and right devices work one at a time but do not work simultaneously, make sure your connected the cameras to separate controller (see important information box above). You can also try a lower resolution or to continue to the next step and select a lower frame rate. However, there is no guarantee that the cameras will work all, even when using separate controllers. Some capture drivers are faulty and unable to handle two devices. Contact the manufacturer and ask for an updated driver.

Stereoscopic Multiplexer capture options

In the third step, you can select a custom frame rate, flip the images or rotate them by 180° (= flipping horizontally and vertically). Flipping is performed in software and works with all kind of capture devices. The chosen frame rate, however, must be supported by the capture device. If you select and unsupported frame rate, the devices either use the closest supported frame rate, the default frame rate or do not work at all. The frame rate options are unavailable if the capture devices support a fixed frame rate only, e.g. DV devices.

Stereoscopic Multiplexer capture options

The last step allows you to set a few options:

  • Synchronized tape playback: More details on DV tape synchronization are available here.
  • Ignore timestamps: Capture drivers set a timestamp on each frame. By default, Stereoscopic Multiplexer uses these timestamps to synchronize left and right video stream. However, timestamps are set by the driver, not by the camera so they do not correspond to recording time necessarily. With some capture devices, Stereoscopic Multiplexer achieves better results by ignoring the timestamps, combining left and right frames in the order they arrive. This applies to DV devices and some webcams.
  • Play audio: Some capture devices deliver both video and audio data. Enable this option to pass audio data from the left capture devices to the sound card. Please note that Stereoscopic Multiplexer doesn't allow to capture audio. The audio data are directly sent to the sound card but are not made available to the capture application. Use Play audio to enable sound when watching video tapes. Usually, this option is set together with Synchronized tape playback.
  • Deinterlace: Enable this option to perform simple deinterlacing. It removes weave artifacts from the video image by dropping every second line of each frame. The Stereoscopic Multiplexer output delivers  half vertical video resolution.

Finally, click Finish. The Stereoscopic Multiplexer will be loaded and you should see left and right image in side-by-side format (right image on the left side for cross-eyed viewing).

Using the Stereoscopic Multiplexer Configurator

The Stereoscopic Multiplexer Configurator provides the following functionality:

  • Configuration of the Stereoscopic Multiplexer: See the previous chapter for more details.
  • Testing the Stereoscopic Multiplexer: Click Driver>Load to load the Stereoscopic Multiplexer and Driver>Unload to unload it. Loading will fail if the left or right capture device is in use by another application. Use Driver>Format Properties and Driver>Device Properties to access the Stereoscopic Multiplexer configuration dialogs. These dialogs can be accessed from other capture tools as well. See the documentation of these tools how to open the capture device settings (the Stereoscopic Multiplexer acts as capture device from the application's point of view).
  • Installing and uninstalling the Stereoscopic Multiplexer: Stereoscopic Multiplexer is a capture driver available to all applications on your system. If an application attempts to load it while it is not configured properly, an error message will be shown. Driver>Uninstall allows you to temporarily disable the Stereoscopic Multiplexer. It remains on the hard disk but is not visible for other applications anymore. To activate it again, click Driver>Install.

The Stereoscopic Multiplexer Configurator is a configuration tool only. It doesn't support capturing to hard disk (yet). We recommend to use the Windows Media Encoder for compressed capturing or live broadcasts or Microsoft AMCap for high quality uncompressed capturing. Both tools are available for free.

Stereoscopic Multiplexer and Stereoscopic Player

Stereoscopic Player is the ideal application to convert Stereoscopic Multiplexer's side-by-side output to any other commonly used stereoscopic format on-the-fly. Make sure you have the latest player version installed.

In Stereoscopic Player, click File>Live Video>Stereoscopic Multiplexer to load the Stereoscopic Multiplexer. Click File>Layout>Side By Side, Right Image First and select the proper aspect ratio in File>Aspect Ratio. Usually, the default aspect ratio will be ok, but if your camcorders are set to 16:9 mode, it must be set to 19:6. In case you use special capture hardware, custom aspect ratios are possible as well.

Select one of the stereoscopic viewing method (= player output format) from View>Viewing Methods.

Stereoscopic Multiplexer Driver Settings

Stereoscopic Multiplexer acts as a WDM capture driver and consequently has two configuration dialogs:

  • Format settings
  • Device settings

Most capture applications allow you to access these dialogs. The format settings are often called capture pin settings as well. In Stereoscopic Player, click File>Device Properties and File>Format Properties, in Stereoscopic Multiplexer Configurator, the same items are available in the Driver menu.

The following screenshot shows the format settings dialog, which consists of the Source and About tabs. The About tab doesn't expose any configuration options so we will not discuss it here.

Stereoscopic Multiplexer source properties

All of the options (except Lock properties) can be selected in the Stereoscopic Multiplexer Configurator's configuration wizard as well (see first chapter). However, this dialog provides more flexibility: It allows experienced users to try settings which cannot be selected in the configuration wizard but doesn't prevent you from choosing invalid settings. We recommend to use the Stereoscopic Multiplexer Configurator to select the capture devices and the capture format. Change the settings in this dialog only if there are strong reasons to do so.

If you set an invalid configuration, the Stereoscopic Multiplexer cannot be loaded anymore in most capture application, so the configuration dialog will be inaccessible. In such a case run the Stereoscopic Multiplexer Configurator's configuration wizard again. (Experienced users can fix the problem using GraphEdit as well.)

Ignore timestamps, Synchronize DV tapes, Play audio and Deinterlace are explained in the first chapter. Lock properties is explained below. Stereoscopic Multiplexer supports the following color spaces.

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

Prefer color spaces which are natively supported by the capture devices, if there are more of them, prefer the one listed top (for performance reasons). If non of the capture device's color spaces are supported by Stereoscopic Multiplexer, try RGB 32 or RGB 24. A video decoder will be used to convert the capture device format to RGB.

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).

The error message 'Stereoscopic Multiplexer could not connect to the left/right device! Maybe the device doesn't support the selected format.' indicates that the selected format or frame rate is unsupported and that no suitable decoder has been found.

Configuration hints:

  • 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 32 or RGB 24 are usually supported).

The device properties dialog has four additional tabs. The Source tab is available as well, but most controls are likely to be be disabled because the format cannot be changed while the Stereoscopic Multiplexer is in use.

Stereoscopic Multiplexer processing properties  Stereoscopic Multiplexer camera control properties
Stereoscopic Multiplexer image settings  Stereoscopic Multiplexer quality properties

Processing: All functions offered on this tab are implemented in the Stereoscopic Multiplexer, so activating them consumes additional CPU power. Gamma, Sharpness, White level, Black level and Convert to ITU-R BT.601 are only available if the YUY2 or UYVY color space 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 example, 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 none of the properties are supported. 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 (parameter synchronization). 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. Lock properties on the Source tab temporarily sets all properties from automatic to manual mode and disables parameter synchronization. Use it to avoid property changes during recording.

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 (contact us for more details). If a correction function has been defined, you can uncheck Corr to temporarily disable it.

Quality: Displays number of processed and dropped frames as well as current time stamps.

Simultaneous Recording & Preview

Stereoscopic Player and Stereoscopic Multiplexer Configurator do 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: Download the latest version 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.