C# real time signal processing

I am doing a c# windows application that plots a real time graph, in time domain, i want to transform this time domain into frequency domain and plot it, and i want to filter the input signal on some frequencies and plot the filtered output,

So basically what i am trying to do is to manipulate the input raw signal, and do some filtration and FFT and other signal processing functionalities,

I want to know if there are some c# functions or libraries that can help me, and if i can matlab libraries to do the functions that will provide me an output i can plot using my own controls not the matlab drawing control