JPiano: Virtual Keyboard and Music Composition Tool

1. JPIANO By Adam Harlow

2. Overview • What is JPiano? • Program design • Some basic music concepts • The Note model • Formulas and algorithms used • The JPiano file extension • Code examples • Limitations and bugs • Future work, Conclusion

3. What is JPiano? • A virtual keyboard spanning one scale • A composing tool • A keyboard learning tool • A toy for tinkering with notes

4. Program design

5. Some basic music concepts 4 4 Number of beats Total number of beats per measure Value of beat Duration of a note, usually a multiple of four (4, 8, 16) Sharp Raises note by one semitone Dot Increases duration of a note by half

6. The Note model • A musical note has two basic properties: • Duration • Tone • The Note class stores these variables, among others, in the model.

7. The Note model (cont’d) 4 4 B G# A E Vector: (qtr)B (qtr)G# (8th)A (qtr*)E Note: The note vector stores Note objects only. The output you see here is stored in a separate String vector.

8. Formulas and algorithms used • Length of one whole note • duration = 4*(60/bpm)*1000 • Pitch calculation • pitch = MIN_PITCH+(12*octave) • MIN_PITCH at C0 is 12 • Regular expression pattern for text output • \([(wh)(hf)(qtr)(8th)(16th)]\*?\)(r|[ABCDEFGc]\#?)

9. The JPiano file extension (.pno) • Output is generated based on each note’s attributes and is stored into a Note vector. • File uses mentioned regex pattern to read and write from a file. • Can be any length. • Can be created by hand in a text file.

10. Note constructor public Note(intbpm, int value, char noteLetter) { this.setBpm(bpm); try { assignDurations(); } catch (NoteDurationExceptionnde) {} try { this.setValue(value); } catch (UndefinedNoteExceptionune) {} this.setNoteLetter(noteLetter); this.isDotted(); this.isSharp(); }

11. Assigning durations from bpm public void assignDurations() throws NoteDurationException{ double ibpm = this.getBpm().intValue(); //note duration in milliseconds is 4*(60/bpm)*1000 defaultDuration= 4*(60/ibpm)*1000; if (defaultDuration <= 0) { throw new NoteDurationException(); } for (Values v : Values.values()) { durations[v.ordinal()] = defaultDuration; defaultDuration /= 2; } }

12. Part of the “insert” Action if (!toggle) { noteString= noteString + "(" + note.getPrefix(); if (note.isDotted()) { noteString= noteString + "*)"; else noteString= noteString + ")"; noteString= noteString + note.getNoteLetter(); if (note.isSharp()) noteString= noteString + "#"; noteString= noteString + " "; noteText.add(noteString); output.append(noteText.lastElement()); note.setNoteOutput(output.getText()); SimpleSynthsynth = new SimpleSynth(); synth= new SimpleSynth((int)note.getDuration(note.getValue()), note.getPitch()); } notes.add(note);

13. Sound playback public SimpleSynth(int duration, int pitch) { //receives parameters from Note attributes … MidiMessagenoteOn = getNoteOnMessage(pitch); rcvr.send(noteOn, 0); try { Thread.sleep(duration); } catch(InterruptedExceptione) { e.printStackTrace(); } MidiMessagenoteOff= getNoteOffMessage(pitch); rcvr.send(noteOff, 0); }

14. Limitations and bugs • Currently no sound output for “Free Play” • Cannot play chords or simultaneous key presses • Octave is not represented in text output • Key binding is wonky at best • Sound cuts off/dies easily if keys are pressed too quickly • No time signatures are supported • Cannot do odd note groupings (e.g. triplets)

15. Future work • Fix the “Free Play” bug • Ensure that notes are properly removed from text area as well as the vectors • Add ability to change instruments • Implement multi-threading in synthesizer • Make a cleaner control layout

16. Conclusion, final thoughts • Object Oriented Programming is ideal for many music-based programs • Can probably make other types of programs with Note model, such as a chord calculator • JPiano did not satisfy original expectations, but came pretty close