Introducing another popular DirectShow project: Vivek’s source filter which emulates a video capture device. For a long time the code was hosted on P “The March Hare” W’s website, which was eventually taken down.
I placed the recovered project, binaries, README and upgrade to Visual Studio 2019 on GitHub: roman380/tmhare.mvps.org-vcam: Original Vivek’s popular sample project implementing virtual DirectShow video source filter (github.com)
The project itself is described in the repository, so I will not duplicate the text here.
See also: How to build and run Vivek’s Virtual Camera on Windows 10? on StackOverflow.