+ /**
+ * Returns the byte array for the given time signature.
+ * @param numerator the numerator of the time signature
+ * @param denominator the denominator of the time signature
+ * @return an array of bytes representing the given time signature
+ */
+ public static byte[] encodeTimeSig(int numerator, int denominator) {
+ byte[] b = {
+ (byte)numerator,
+ (byte)(Math.log(denominator) / Math.log(2)), // logarithm of denominator in base 2
+ (byte)96,
+ (byte)8
+ };
+ return b;
+ }
+ /**
+ * Returns the time signature for the given byte array.
+ * @param an array of four bytes representing the time signature
+ * @return an array of two integers where [0] is the numerator and [1] the denominator
+ */
+ public static int[] decodeTimeSig(byte[] bytes) {
+ int[] t = {
+ (int)bytes[0],
+ (int)(1 << bytes[1])
+ };
+ return t;
+ }
+
+ /**
+ * Returns the time signature in the given tick position.
+ * @param tick the tick position for which to return the time signature
+ * @return an array of two integers where [0] is the numerator and [1] the denominator
+ */
+ public static int[] getTimeSig(long tick) {
+ int[] ts = {4, 4};
+ if (timeSignatures.size() == 0) return ts;
+ MidiEvent timeSigEvent = (MidiEvent)timeSignatures.get(0);
+ if (timeSignatures.size() > 1) {
+ for (int i = 1; i < timeSignatures.size(); i++) {
+ MidiEvent nextTimeSigEvent = (MidiEvent)timeSignatures.get(i);
+ if (nextTimeSigEvent.getTick() <= tick && nextTimeSigEvent.getTick() > timeSigEvent.getTick())
+ timeSigEvent = nextTimeSigEvent;
+ }
+ }
+ return decodeTimeSig(((MetaMessage)timeSigEvent.getMessage()).getData());
+ }
+
+ /**
+ * Sets the time signature at the given tick position.
+ * @param ticks the tick position
+ */
+ public static void setTimeSig(long tick, int numerator, int denominator) {
+ // Checks for a time signature event at the given tick position.
+ MidiEvent timeSigEvent = null;
+ Iterator it = timeSignatures.iterator();
+ while(it.hasNext()) {
+ MidiEvent nextTimeSigEvent = (MidiEvent)it.next();
+ if (nextTimeSigEvent.getTick() == tick) {
+ timeSigEvent = nextTimeSigEvent;
+ break;
+ }
+ }
+
+ // If none was found, creates and adds a new one.
+ if (timeSigEvent == null) {
+ timeSigEvent = new MidiEvent(new MetaMessage(), tick);
+ (seq.getTracks())[0].add(timeSigEvent);
+ timeSignatures.add(timeSigEvent);
+ Collections.sort(timeSignatures, new MidiEventComparator());
+ }
+
+ // Sets the time signature of the event (found or created).
+ try {
+ ((MetaMessage)timeSigEvent.getMessage()).setMessage(88, encodeTimeSig(numerator, denominator), 4);
+ } catch (InvalidMidiDataException e) {}
+ }
+
+ /**
+ * Calculates the position (measures, beats, ticks) in the current sequence for the given tick position.
+ * @param tickPosition the tick position for which to calculate the position
+ * @return an array of integers where index 0 is measures, 1 is beats and 2 is ticks.
+ */
+ public static int[] getPositionForTicks(long tickPosition) {
+ int ticksPerBeat = seq.getResolution();
+ long measures = 0, beats = 0, ticks = 0;
+
+ // Counts for each time signature change up to the last one before the given tick position.
+ Iterator it = timeSignatures.iterator();
+ MidiEvent lastTSEvent = (MidiEvent)it.next();
+ while(it.hasNext()) {
+ MidiEvent nextTSEvent = (MidiEvent)it.next();
+ if (nextTSEvent.getTick() > tickPosition) break;
+ long tickDiff = nextTSEvent.getTick() - lastTSEvent.getTick();
+ int[] ts = decodeTimeSig(((MetaMessage)lastTSEvent.getMessage()).getData());
+ int beatsPerMeasure = ts[0] * (4 / ts[1]);
+ long thisTSMeasures = tickDiff / (beatsPerMeasure * ticksPerBeat);
+ measures += thisTSMeasures;
+ long thisTSBeats = (tickDiff - thisTSMeasures * beatsPerMeasure * ticksPerBeat) / ticksPerBeat;
+ beats += thisTSBeats;
+ ticks += tickDiff - thisTSMeasures * beatsPerMeasure * ticksPerBeat - thisTSBeats * ticksPerBeat;
+ lastTSEvent = nextTSEvent;
+ }
+
+ // Counts from the given tick position to the last time signature change before it.
+ long tickDiff = tickPosition - lastTSEvent.getTick();
+ int[] ts = decodeTimeSig(((MetaMessage)lastTSEvent.getMessage()).getData());
+ int beatsPerMeasure = ts[0] * (4 / ts[1]);
+ long thisTSMeasures = tickDiff / (beatsPerMeasure * ticksPerBeat);
+ measures += thisTSMeasures;
+ long thisTSBeats = (tickDiff - thisTSMeasures * beatsPerMeasure * ticksPerBeat) / ticksPerBeat;
+ beats += thisTSBeats;
+ ticks += tickDiff - thisTSMeasures * beatsPerMeasure * ticksPerBeat - thisTSBeats * ticksPerBeat;
+
+ // Corrects any overflows.
+ if (ticks > ticksPerBeat) {
+ beats += Math.floor(ticks / ticksPerBeat);
+ ticks = ticks % ticksPerBeat;
+ }
+ if (beats > beatsPerMeasure) {
+ measures += Math.floor(beats / beatsPerMeasure);
+ beats = beats % beatsPerMeasure;
+ }
+
+ // Returns the calculated values.
+ int[] pos = {(int)measures, (int)beats, (int)ticks};
+ return pos;
+ }
+
+ /**
+ * Calculates the tick position in the current sequence for the given position (measures, beats, ticks).
+ * @param measures the measure of the current position
+ * @param beats the beat of the current position
+ * @param tick the tick of the current position
+ * @return the tick position.
+ */
+ public static long getTicksForPosition(int measures, int beats, int ticks) {
+ int res = seq.getResolution();
+ int[] lastTSPos = new int[3];
+ long tickPosition = 0;
+
+ // Counts for each time signature change up to the last one before the given tick position.
+ Iterator it = timeSignatures.iterator();
+ MidiEvent lastTSEvent = (MidiEvent)it.next();
+ while(it.hasNext()) {
+ MidiEvent nextTSEvent = (MidiEvent)it.next();
+ int[] nextTSPos = getPositionForTicks(nextTSEvent.getTick());
+ if (nextTSPos[0] >= measures) break;
+ lastTSPos = nextTSPos;
+ lastTSEvent = nextTSEvent;
+ }
+
+ // Counts from the given tick position to the last time signature change before it.
+ int measdiff = measures - lastTSPos[0];
+ int[] ts = decodeTimeSig(((MetaMessage)lastTSEvent.getMessage()).getData());
+ int beatsPerMeasure = ts[0] * (4 / ts[1]);
+ tickPosition = lastTSEvent.getTick() + (beatsPerMeasure * measures + beats) * res + ticks;
+
+ return tickPosition;
+ }
+
+
+
+
+
+
+
+
+ /* ***
+ ** SYSTEM & IO METHODS **
+ *** */
+
+
+
+
+
+
+
+
+ /**
+ * Replaces the current sequence with a new one, holding three empty tracks.
+ */
+ public static void clearSequence() {
+ // Reinitializes sequence variables
+ file = null;
+ reinitializeLists();
+
+ try {
+ // Creates a new sequence.
+ seq = new Sequence(Sequence.PPQ, DEFAULT_RESOLUTION, DEFAULT_TRACKS);
+ Track[] tracks = seq.getTracks();
+
+ // Sets default tempo (120) and time signature (4/4) at the beginning of the sequence.
+ setTempo(0, 120);
+ setTimeSig(0, 4, 4);
+
+ // Sets program and title for the tracks.
+ initializeTrack(tracks[1], 0, 24, "Guitar");
+ initializeTrack(tracks[2], 1, 33, "Bass");
+ initializeTrack(tracks[3], 9, 0, "Drums");
+ } catch (InvalidMidiDataException e) {}
+
+ // Sends the sequence to the GUI.
+ if (gui != null) gui.setSequence(seq, null);
+ }
+
+ /**
+ * Creates event in the given track for program change and title.
+ */
+ private static void initializeTrack(Track track, int channel, int program, String title) {
+ // Creates program change and title message.
+ ShortMessage programMsg = new ShortMessage();
+ MetaMessage titleMsg = new MetaMessage();
+
+ // Sets the data of the messages.
+ try {
+ programMsg.setMessage(ShortMessage.PROGRAM_CHANGE, channel, program, 0);
+ titleMsg.setMessage(3, title.getBytes(), title.length());
+ } catch (InvalidMidiDataException e) {}
+
+ // Sends the program change to the channel
+ getChannel(channel).programChange(program);
+
+ // Adds them to the track.
+ track.add(new MidiEvent(programMsg, (long)0));
+ track.add(new MidiEvent(titleMsg, (long)0));
+ }
+
+ /**
+ * Wraps each NoteOn event in the track with its NoteOff event in a MooNote.
+ * @param track the track to convert
+ * @param quantize whether to round locations and durations in the track to nearest 16th
+ * @return a list of the created MooNotes
+ */
+ public static List convertTrack(Track track) {
+ // Searches the track for NoteOn and NoteOff events
+ ArrayList noteOns = new ArrayList(track.size() / 2);
+ ArrayList noteOffs = new ArrayList(track.size() / 2);
+ ArrayList newMooNotes = new ArrayList();
+ MidiEvent event;
+ for (int j = 0; j < track.size(); j++) {
+ event = track.get(j);
+ if (event.getMessage().getStatus() >= 144 &&
+ event.getMessage().getStatus() < 160) noteOns.add(event);
+ if (event.getMessage().getStatus() >= 128 &&
+ event.getMessage().getStatus() < 144) noteOffs.add(event);
+ }
+ noteOns.trimToSize();
+ noteOffs.trimToSize();
+ if (noteOns.size() == 0) emptyTracks.add(track);
+
+ // Sorts the note lists by tick position.
+ Comparator c = new MidiEventComparator();
+ Collections.sort(noteOns, c);
+ Collections.sort(noteOffs, c);
+
+ // Replaces each NoteOn event it with a MooNote containing a reference to the NoteOff event.
+ Iterator iOn = noteOns.iterator(), iOff;
+ MidiEvent on, off = null, nextOff;
+ ShortMessage onMsg, nextOffMsg;
+ while(iOn.hasNext()) {
+ on = (MidiEvent)iOn.next();
+ if (!(on instanceof MooNote)) {
+ onMsg = (ShortMessage)on.getMessage();
+ iOff = noteOffs.iterator();
+ while(iOff.hasNext()) {
+ nextOff = (MidiEvent)iOff.next();
+ nextOffMsg = (ShortMessage)nextOff.getMessage();
+ if(onMsg.getChannel() == nextOffMsg.getChannel() &&
+ onMsg.getData1() == nextOffMsg.getData1() &&
+ c.compare(nextOff, on) > 0) {
+ off = nextOff;
+ iOff.remove();
+ break;
+ }
+
+ }
+ track.remove(on);
+ MooNote mn;
+ if (off != null) {
+ mn = new MooNote(on, off);
+ } else {
+ mn = new MooNote(on, new MidiEvent((ShortMessage)on.getMessage().clone(), on.getTick() + 48));
+ }
+ track.add(mn);
+ newMooNotes.add(mn);
+ iOn.remove();
+ }
+ }
+ return newMooNotes;
+ }
+
+ /**
+ * Loads a MIDI sequence from the given file.