Implementation of full JACK support for MuseScore

by Maxim Grishin for MuseScore

My goal is to implement full JACK (JACK Audio Connection Kit) support in MuseScore 2.0. MuseScore already has a Jack Audio support, but doesn't have a support of Jack MIDI In/Out and Jack Transport. Features to be implemented: 1. Jack MIDI Out: outputs midi messages. 2. Jack Transport: start, stop and seek. 3. Jack MIDI In: handles incoming midi messages. 4. Jack Audio: outputs an audio. These features will give an ability to connect with lots of synthesizers and DAWs.