NiCMidi is a MIDI library written in C++ by Nicola Cassetta, which implements objects for playing, recording, editing and saving MIDI content. It was originally a fork of jdkmidi, an old similar library written by J. D. Koftinoff and no more updated (see https://github.com/jdkoftinoff/jdksmidi). The author has rewritten the old code, adding many new features and using a more modern C++ style.

You can start learning it by reading the Overview section.