Convolution / Image Filtering

[ThatGeoGuy]

Hey all, I've been using Math.NET Numerics for some time now, but can't seem to find anything that would help me perform a 2D convolution over an image (both kernel and image represented as Matrix<double>).

I understand via issue #157 that 2D FFT isn't provided yet; however, as I am only applying 3x3 Sobel filters for the time being, I'm not sure that I need a full FFT / IFFT to perform the convolution in frequency-space.

Is there any way currently to convolve a kernel of some kind over a larger matrix? Which packages from Math.NET should I install via NuGet to ensure I can use it?