This is a plug-in that I am currently developing for my Master's Thesis. It is an implementation of an up-mixing algorithm.
In order to compile the plug-in, you will need to download and set up the JUCE library and Projucer software. Then download and set up Steinberg's VST3 SDK into JUCE.
The algorithm up-mixes 2 channel stereo signals for 5.1 surround reproduction.