Check out the Intel® Integrated Performance Primitives (Intel® IPP) C# support sample ( Download it from Intel IPP Sample Page), it is included in part of Intel IPP samples for Windows. The sample is located in Intel IPP sample directory \ipp-samples\language-interface\dotnet-cpp
It demonstrates how to use Intel IPP when developing applications in the Microsoft C# environment. Includes wrapper classes to support Intel IPP string manipulations, image, signal processing, color conversion, cryptography, data compression, JPEG, matrix and vector math, etc.
Additionally, there is a complete white paper to address C# support in Intel® Performance Libraires including Intel IPP and Intel® Math Kernel Library ( Intel MKL), please visit here for more reference.