How to create the new algorithm

How to create the new algorithm

to create the new blending algorithm you have to implement

public interface IBlendAlgorithm : IAlgorithm
{
    Color Calculate(IEnumerable<Colour> colours);
}

colours - a collection of pixels which will be handled and as a result, the new colour will be returned. You can handle them whatever you can imagine. Pull requests with the examples of algorithm's working are welcome!