I'm making a project with OpenCV about tracking. But what I want is the ability to let the user import his own tracking algorithms. Is there some way that i can check in a specified folder if there are new algorithms added and how can I include them in my code? So i want to check if there are other algorithms added and 'load' them in to my code and execute them. How can I do this?

The algorithms always have the same amount of parameters.

In Linux, the library for dynamic loading a library into the caller's address space is called dl, use the function dlopen to load and dlsym to resolve the function you are interested in calling. In Windows the function is called LoadLibrary and is a part of Kernel32.dll (defined in Windows.h).

Linux example: see the dlopen manual
Windows example: msdn.microsoft.com