I am developing an application for a touchpad where I use capacitive buttons in conjunction with the MIDI protocol to play some music notes. I would like to change the "velocity" parameter inside the library. This change must correspond to the pressure applied to the capacitive sensor touch. For example when you are playing the piano and you press the key harder. I'm not sure what function to use to do this. The parameter should vary with the variation of capacitance at the finger touch on the capacitive sensor. Any suggestions?