Processing MidiMessages

Hello everyone, I’m new to Juice and am just taking my first steps.

I want to create a standalone application that receives MIDI data from a keyboard via an external soundcard and changes values (for example pitch or velocity). The changed values should then be available to other programs, for example a software piano, as input data.

A simple program based on the Juce tutorials already works as a plug-in. The values changed in the processBlock of the AudioProcessor are changed as expected and played via the integrated sounds of the host.

Unfortunately, I can’t find a way to implement this as a standalone as described. Do I have to create additional MidiDevices and redirect the MidiOutput?
Thanks for any advice or a link if something similar has already been discussed.

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