metdetection.time

Class TimeTracker

java.lang.Object

metdetection.time.TimeTracker

public class TimeTracker
extends java.lang.Object

A TimeTracker is able to interpret MIDI tempo, key, and time signature change events and keep track of the song timing in seconds, instead of just using ticks as MIDI events do. It does this by using a LinkedList of TimeTrackerNode objects.

Author:

Andrew McLeod - 23 October, 2014

Field Summary

Fields

Modifier and Type	Field and Description
private int	anacrusisLength The number of ticks which lie before the first full measure in this song.
private long	lastTick The last tick for any event in this song, initially 0.
private java.util.LinkedList<TimeTrackerNode>	nodes The LInkedList of TimeTrackerNodes of this TimeTracker, ordered by time.
private double	PPQ Pulses (ticks) per Quarter note, as in the current Midi song's header.

Constructor Summary

Constructors

Constructor and Description
TimeTracker() Create a new TimeTracker.

Method Summary

Methods

Modifier and Type	Method and Description
void	addKeySignatureChange(long tick, int keyNumber, boolean isMajor) Change the key to the given value.
void	addKeySignatureChange(javax.sound.midi.MidiEvent event, javax.sound.midi.MetaMessage mm) A KeySignature event was detected.
void	addTempoChange(long tick, int qpm) Change the tempo to the given number of quarter notes per minute.
void	addTempoChange(javax.sound.midi.MidiEvent event, javax.sound.midi.MetaMessage mm) A Tempo event was detected.
void	addTimeSignatureChange(long tick, int numerator, int denominator) Change the time signature to the given value.
void	addTimeSignatureChange(javax.sound.midi.MidiEvent event, javax.sound.midi.MetaMessage mm) A TimeSignature event was detected.
java.util.List<TimeSignature>	getAllTimeSignatures() Get a List of all of the time signatures of this TimeTracker, excluding the dummy one.
int	getAnacrusisSubBeats() Get the anacrusis length of this TimeTracker, in sub beats.
int	getAnacrusisTicks() Get the anacrusis length of this TimeTracker, in ticks.
java.util.List<Beat>	getBeats() Get a List of the Beats found by this TimeTracker up until (but not including) the lastTick.
TimeSignature	getFirstTimeSignature() Get the first non-dummy time signature in this song.
long	getLastTick() Get the last tick for this song.
private TimeTrackerNode	getNodeAtTick(long tick) Get the TimeTrackerNode which is valid at the given tick.
TimeTrackerNode	getNodeAtTime(long time) Get the TimeTrackerNode which is valid at the given time.
java.util.LinkedList<TimeTrackerNode>	getNodes() Get a list of the TimeTrackerNodes tracked by this object.
double	getPPQ() Get the PPQ of this TimeTracker.
double	getQuantizationError(MidiNote note, int divisions) Get the quantization error of the given note, with the given number of divisions per quarter note.
long	getTickAtTime(long time) Gets the tick number at the given time, measured in microseconds.
long	getTimeAtTick(long tick) Returns the time in microseconds of a given tick number.
void	setAnacrusis(int length) Set the anacrusis length of this song to the given number of ticks.
void	setLastTick(long lastTick) Set the last tick for this song to the given value.
void	setPPQ(double ppq) Set the PPQ for this TimeTracker.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

PPQ

private double PPQ

Pulses (ticks) per Quarter note, as in the current Midi song's header.

nodes

private final java.util.LinkedList<TimeTrackerNode> nodes

The LInkedList of TimeTrackerNodes of this TimeTracker, ordered by time.

anacrusisLength

private int anacrusisLength

The number of ticks which lie before the first full measure in this song.

lastTick

private long lastTick

The last tick for any event in this song, initially 0.

Constructor Detail

TimeTracker

public TimeTracker()

Create a new TimeTracker.

Method Detail

addTimeSignatureChange

public void addTimeSignatureChange(javax.sound.midi.MidiEvent event,
                          javax.sound.midi.MetaMessage mm)

A TimeSignature event was detected. Deal with it.

Parameters:

event - The event.

mm - The message from the event.

addTimeSignatureChange

public void addTimeSignatureChange(long tick,
                          int numerator,
                          int denominator)

Change the time signature to the given value.

Parameters:

tick - The tick at which the time signature was changed.

numerator - The numerator.

denominator - The denominator.

addTempoChange

public void addTempoChange(javax.sound.midi.MidiEvent event,
                  javax.sound.midi.MetaMessage mm)

A Tempo event was detected. Deal with it.

Parameters:

event - The event.

mm - The message from the event.

addTempoChange

public void addTempoChange(long tick,
                  int qpm)

Change the tempo to the given number of quarter notes per minute.

Parameters:

tick - The tick at which to make the given change.

qpm - The number of quarter notes per minute for the new tempo.

addKeySignatureChange

public void addKeySignatureChange(javax.sound.midi.MidiEvent event,
                         javax.sound.midi.MetaMessage mm)

A KeySignature event was detected. Deal with it.

Parameters:

event - The event.

mm - The message from the event.

addKeySignatureChange

public void addKeySignatureChange(long tick,
                         int keyNumber,
                         boolean isMajor)

Change the key to the given value.

Parameters:

tick - The tick at which to change the key.

keyNumber - The key number to change to.

isMajor - Whether that key is major or minor.

getTimeAtTick

public long getTimeAtTick(long tick)

Returns the time in microseconds of a given tick number.

Parameters:

tick - The tick number to calculate the time of

Returns:

The time of the given tick number, measured in microseconds since the most recent epoch.

getNodeAtTick

private TimeTrackerNode getNodeAtTick(long tick)

Get the TimeTrackerNode which is valid at the given tick.

Parameters:

tick - The tick.

Returns:

The valid TimeTrackerNode.

getTickAtTime

public long getTickAtTime(long time)

Gets the tick number at the given time, measured in microseconds.

Parameters:

time - The time in microseconds whose tick number we want.

Returns:

The tick number which corresponds to the given time.

getNodeAtTime

public TimeTrackerNode getNodeAtTime(long time)

Get the TimeTrackerNode which is valid at the given time.

Parameters:

time - The time.

Returns:

The valid TimeTrackerNode.

getAllTimeSignatures

public java.util.List<TimeSignature> getAllTimeSignatures()

Get a List of all of the time signatures of this TimeTracker, excluding the dummy one.

Returns:

A List of all of the time signatures of this TimeTracker, excluding the dummy one.

getBeats

public java.util.List<Beat> getBeats()

Get a List of the Beats found by this TimeTracker up until (but not including) the lastTick.

Returns:

A List of the 32nd-note Beats of this TimeTracker until the given tick.

getQuantizationError

public double getQuantizationError(MidiNote note,
                          int divisions)

Get the quantization error of the given note, with the given number of divisions per quarter note.

Parameters:

note - The note whose quantization error we want.

divisions - The number of divisions per quarter note.

Returns:

The quantization error of the given note's onset, as a percentage of the quarter note length.

getFirstTimeSignature

public TimeSignature getFirstTimeSignature()

Get the first non-dummy time signature in this song.

Returns:

The TimeSignature of the first node which isn't a dummy, or the initial dummy TimeSignature if there is none.

getAnacrusisSubBeats

public int getAnacrusisSubBeats()

Get the anacrusis length of this TimeTracker, in sub beats.

Returns:

anacrusisLength, in sub beats

getAnacrusisTicks

public int getAnacrusisTicks()

Get the anacrusis length of this TimeTracker, in ticks.

Returns:

anacrusisLength

setAnacrusis

public void setAnacrusis(int length)

Set the anacrusis length of this song to the given number of ticks.

Parameters:

length - The anacrusis length of this song, measured in ticks.

getNodes

public java.util.LinkedList<TimeTrackerNode> getNodes()

Get a list of the TimeTrackerNodes tracked by this object.

Returns:

nodes

setLastTick

public void setLastTick(long lastTick)

Set the last tick for this song to the given value.

Parameters:

lastTick - lastTick

getLastTick

public long getLastTick()

Get the last tick for this song.

Returns:

lastTick

setPPQ

public void setPPQ(double ppq)

Set the PPQ for this TimeTracker.

Parameters:

ppq - PPQ

getPPQ

public double getPPQ()

Get the PPQ of this TimeTracker.

Returns:

PPQ

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object