This section provides general FAQs.

Hardware

When I switch between Tracking configuration files, my camera freezes. The same happens when I pause/unpause the camera.

If you are using a Logitech camera this is a known issue in the Logitech driver especially when using resolutions higher than 640x480. As a workaround you can just open and close the camera resolution/camera properties dialog which forces the camera to reinitialize. You can also try updating the driver.

My AVT camera does not work.

If you are using an Allied Vision Technologies camera, please make sure to install the according AVT driver version for the Unifeye SDK version you are using. Every version of the Unifeye SDK also corresponds to a specific driver version of the AVT FirePackage (and AVT Universal Package from Unifeye SDK version 4.0 on). You can find out which AVT driver versions you need in the Unifeye SDK version history.

Image/video/camera loading

When I load a large still image file (> 2000x2000px) and try to apply the according extended camera (Extended Sextant) calibration file afterwards, the system always complains about an image dimension mismatch and switches back to the default settings.

Camera calibration files are only valid for one specific camera resolution. When loading extended camera calibration files (Extended Sextant) the image resolution of the currently loaded image and the resolution stored within the calibration file are compared. If there is a mismatch, the system informs the user and falls back to default settings in order to prevent e.g. faulty measurements.

Sometimes and on some machines you run into this behaviour although you are definitely loading a correct calibration for the correct image. This can happen if the DirectShow configuration on your system is broken or misconfigured which can happen e.g. by the installation of certain CODEC or grabber packages. Those packages can overwrite the systems default image loader filters used in DirectShow causing e.g. an automatic adjustment/downscale of every image you are trying to load. This results in the error message as the image arriving in Unifeye was manipulated/downscaled before by the filter and now doesn't fit the calibration file any more. Filters/packages known to cause such problems are:

• DC ImageFilter (by ???)

Try uninstalling the according CODEC/grabber package for solving this issue. There are also tools available for fixing the DirectShow installation but they are tricky to handle. In the worst case you will have to setup your OS from scratch.

I don't get an image using DeckLink HD capture cards on native 64 bit systems and Unifeye 64

As illustrated here you need to configure the HD capture card properly beforing using it in Unifeye. If you are working on a 64 bit system using Unifeye 64 you will also have to use the 64 bit version of GraphEdit for that purpose. You can download it from the Internet.

Content loading

In Unifeye SDK Professional movie textures do not work

If you want to use movie textures Unifeye SDK Professional please proceed with the approach described here and run the renderer in DirectX mode. If you want to start the movies programmatically it can happen that you sometimes only get a black texture. This happens when the movie hasn't properly finished loading. To avoid such issues you should, before starting the movie, check if it has finished loading. The following C# code assumes that the sample provided here is being used:

if (m_UnifeyeControl.getVrmlField(sceneIDofMovieVRML, “MOVIE”, “isLoaded” == “TRUE”)
{
    m_UnifeyeControl.startTimer(sceneIDofMovieVRML, -1, "TIMER_START_MOVIE", 0.0f);
}

where m_UnifeyeControl is the reference to the Unifeye ActiveX control and sceneIDofMovieVRML contains the id returned by loadGeometry() when loading the VRML file with the movie texture. In cases where "isLoaded" does not equal "TRUE" you should not start the timer for the movie texture but repeat this step after e.g. 100ms. This should best be done using a Windows Forms timer callback and not active waiting as active waiting will block also the renderer.

Using Unifeye SDK Ultimate 4.0 I can't load .wrz files any more?

You can load .wrz (gzipped VRML files) if you simply use the normal file extension .wrl. So please rename .wrz files to .wrl and Unifeye SDK Ultimate will load it.

Programming

My .Net (C# or VB.Net program) using the Unifeye SDK when run from Visual Studio causes a "LoaderLock" Exception.

This only happens when run from within Visual Studio and only on some computers. You can ignore this exception in Visual Studio. Go to "Debugging" -> "Exceptions" -> "Managed Debugging Assistants" and uncheck the checkbox for "LoaderLock".

How can I use the Unifeye SDK in a Windows Presentation Foundation (WPF) application?

Please refer to the according article in the development section.

My application exists directly after start-up when starting from Visual Studio

This seems to be a compatibility issue on some machines when creating applications using .Net Framework 4.0 (which you e.g. need for WPF based applications). This will be solved in the next version. For now (as a work around) you can compile your application and start the resulting .exe file directly (e.g. using the Windows file explorer). Then attach the Visual Studio debugger to it (Debugging -> Attach to process -> Select the according process and attach).

-- SupportMetaio - 2010-03-19