A VL wrapper for OpenCVSharp
Clone or download
Latest commit 4e8142e Oct 23, 2018



A VL wrapper for OpenCV based on OpenCVSharp3-AnyCPU and also using DirectShowLib.

Using the library

In order to use this library with vl you have to install the nuget that is available via nuget.org. For information on how to use nugets with vl, see Managing Nugets in the vl documentation. As described there you go to the commandline and then type:

nuget install VL.OpenCV -prerelease

Once the VL.OpenCV nuget is installed and referenced in your vl document you'll see the category "OpenCV" in the nodebrowser. From there explore the nodes in its main sub-categories:

  • Source (VideoIn, ImageFile,...)
  • Sink (Renderer, VideoFile,...)
  • Filter (Blur, Dilate, Sobel,...)
  • Tracker (Contours, ObjectDetector, MedianFlow,...)

There is also a demo-patch coming with this package that is a bit hidden in:


Contributing to the development

If you want to contribute to this repository, clone it into a directory like:


Build the C# Project



in VisualStudio and build it. This is necessary for a few things that cannot yet be expressed in vl directly, like dynamic enums and static readonly instances of things.

Get Nuget Dependency

This wrapper is depending on the thirdparty nuget OpenCVSharp3-AnyCPU. When installing the VL.OpenCV nuget as mentioned under "Using the library" above, this dependency will be installed automatically. To install it otherwise, go to your vvvvs


on a commandline and run

nuget.exe install OpenCVSharp3-AnyCPU

Start vvvv

Then start vvvv with the commandline parameter:

/package-repositories "X:\vl-libs\"

which will make all packs found in that directory available as dependencies in vl documents. Note that it is possible to have both the nuget (binary) and the sources available. If both are found, the one in the "package-repositories" path is used. Like this you can easily switch between your local development version and the "official" nuget by simply including your local version in that search path or not.

VL.OpenCV will now show up as Nuget among a documents dependencies as shown here.