Right clicking on a node in graph widget should trigger event chain to eventually start drawing line. Clicking on another node should connect two nodes with that line and register connection in some sort of graph matrix.

Improve component factory classes. Might be good to use templates for that to create a common interface for creating several families of components. They might be distinguished by an enum class, which will be later defined

The class pipeline already exist but its empty.
Class should contain array of pointers to component functions and have access to graph connection matrix and some method like execute() which will process all scheduled tasks. It might be triggered by external signal.

Functor class is supposed to work as variadic function wrapper, so it can hold a function with various argument types and return type. It will be then constructed as a member of specific component class, as in MedianBlur class example. There will be much more similar classes, e.g. GaussianBlur, RGB2Grayscale etc., so it might be convenient to have a common interface for defining them and functions that they represent, without copy pasting too much code.

It would also be great if class component could hold informations about its functor arguments and types (and maybe limits), so later they can be set by clicking on its gui representation.

Need to implement option in cmake to allow compilation with code coverage flags and adopt some test framework (gtest and/or cppunit?)