Package org.jjazz.midi.api.sequencer

Class MidiUtils

java.lang.Object

org.jjazz.midi.api.sequencer.MidiUtils

public final class MidiUtils
extends Object

Some utilities for MIDI (some stuff is used from javax.sound.midi)

Author:

Florian Bomers

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	MidiUtils.TempoCache

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_TEMPO_MPQ
static final int	META_END_OF_TRACK_TYPE
static final int	META_TEMPO_TYPE

Method Summary

Modifier and Type	Method	Description
static void	checkSysexStatus(byte[] data, int length)	Checks the status byte for the system exclusive message.
static void	checkSysexStatus(int status)	Checks the status byte for the system exclusive message.
static double	convertTempo(double tempo)	converts 1 - MPQ-Tempo to BPM tempo 2 - BPM tempo to MPQ tempo
static int	getTempoMPQ(MidiMessage midiMsg)	parses this message for a META tempo message and returns the tempo in MPQ, or -1 if this isn't a tempo message
static boolean	isMetaEndOfTrack(MidiMessage midiMsg)	return true if the passed message is Meta End Of Track
static boolean	isMetaTempo(MidiMessage midiMsg)	return if the given message is a meta tempo message
static long	microsec2ticks(long us, double tempoMPQ, int resolution)	convert tempo to microsecond with given tempo Does not take tempo changes into account.
static long	microsecond2tick(Sequence seq, long micros, MidiUtils.TempoCache cache)	Given a microsecond time, convert to tick. returns tempo at the given time in cache.getCurrTempoMPQ
static int	tick2index(Track track, long tick)	Binary search for the event indexes of the track
static long	tick2microsecond(Sequence seq, long tick, MidiUtils.TempoCache cache)	Given a tick, convert to microsecond
static long	ticks2microsec(long tick, double tempoMPQ, int resolution)	convert tick to microsecond with given tempo.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DEFAULT_TEMPO_MPQ

public static final int DEFAULT_TEMPO_MPQ

See Also:

• Constant Field Values

META_END_OF_TRACK_TYPE

public static final int META_END_OF_TRACK_TYPE

See Also:

• Constant Field Values

META_TEMPO_TYPE

public static final int META_TEMPO_TYPE

See Also:

• Constant Field Values

Method Details

checkSysexStatus

public static void checkSysexStatus(byte[] data,
 int length)
                             throws InvalidMidiDataException

Checks the status byte for the system exclusive message.

Parameters:

data - the system exclusive message data

length - the length of the valid message data in the array

Throws:

InvalidMidiDataException - if the status byte is invalid for a system exclusive message

checkSysexStatus

public static void checkSysexStatus(int status)
                             throws InvalidMidiDataException

Checks the status byte for the system exclusive message.

Parameters:

status - the status byte for the message (0xF0 or 0xF7)

Throws:

InvalidMidiDataException - if the status byte is invalid for a system exclusive message

isMetaEndOfTrack

public static boolean isMetaEndOfTrack(MidiMessage midiMsg)

return true if the passed message is Meta End Of Track

isMetaTempo

public static boolean isMetaTempo(MidiMessage midiMsg)

return if the given message is a meta tempo message

getTempoMPQ

public static int getTempoMPQ(MidiMessage midiMsg)

parses this message for a META tempo message and returns the tempo in MPQ, or -1 if this isn't a tempo message

convertTempo

public static double convertTempo(double tempo)

converts
1 - MPQ-Tempo to BPM tempo
2 - BPM tempo to MPQ tempo

ticks2microsec

public static long ticks2microsec(long tick,
 double tempoMPQ,
 int resolution)

convert tick to microsecond with given tempo. Does not take tempo changes into account. Does not work for SMPTE timing!

microsec2ticks

public static long microsec2ticks(long us,
 double tempoMPQ,
 int resolution)

convert tempo to microsecond with given tempo Does not take tempo changes into account. Does not work for SMPTE timing!

tick2microsecond

public static long tick2microsecond(Sequence seq,
 long tick,
 MidiUtils.TempoCache cache)

Given a tick, convert to microsecond

Parameters:

cache - tempo info and current tempo

microsecond2tick

public static long microsecond2tick(Sequence seq,
 long micros,
 MidiUtils.TempoCache cache)

Given a microsecond time, convert to tick. returns tempo at the given time in cache.getCurrTempoMPQ

tick2index

public static int tick2index(Track track,
 long tick)

Binary search for the event indexes of the track

Parameters:

tick - tick number of index to be found in array

Returns:

index in track which is on or after "tick". if no entries are found that follow after tick, track.size() is returned