org.openimaj.audio.util

Class WesternScaleNote

java.lang.Object

org.openimaj.audio.util.WesternScaleNote

public class WesternScaleNote
extends Object

Represents a note in a standard equal-tempered Western scale. There are various static methods for creating notes from names, note numbers, and frequencies.

Author:

David Dupplaw (dpd@ecs.soton.ac.uk)

See Also:

"http://www.musicdsp.org/showone.php?id=125"

Created:

27 Nov 2011

Field Summary

Fields

Modifier and Type	Field and Description
float	frequency The frequency of the note
String	noteName The note name; e.g.
static String[]	noteNames The names of the notes in the Western scale
int	noteNumber The MIDI note number of the note
int	octaveNumber The octave number.
static float	tuningOfA The standing tuning is A=440Hz.
static double	twelfthRootOfTwo The twelfth root of 2

Constructor Summary

Constructors

Constructor and Description
WesternScaleNote()

Method Summary

Modifier and Type	Method and Description
static WesternScaleNote	createNote(float frequency) Create a WesternScaleNote given a frequency.
static WesternScaleNote	createNote(int noteNumber) Given a note number, returns a WesternScaleNote from which other information can be garnered.
static WesternScaleNote	createNote(String noteString) Given a note string, returns a new WesternScaleNote from which other information can be garnered.
static WesternScaleNote	createNote(String noteName, int octaveNumber) Given a note name and octave, returns a WesternScaleNote from which other information can be garnered.
static int	frequencyToNote(float frequency) Converts a frequency to the nearest note number
static float	noteToFrequency(int noteNumber) Converts a MIDI note number to a frequency.
static int	nStepsBetween(WesternScaleNote note1, WesternScaleNote note2) Returns the number of half-steps between the two given notes.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

noteNumber

public int noteNumber

The MIDI note number of the note

noteName

public String noteName

The note name; e.g. C, D, F#, etc.

octaveNumber

public int octaveNumber

The octave number. Note C4 is middle C

frequency

public float frequency

The frequency of the note

tuningOfA

public static float tuningOfA

The standing tuning is A=440Hz. Can change that here.

twelfthRootOfTwo

public static final double twelfthRootOfTwo

The twelfth root of 2

See Also:

Constant Field Values

noteNames

public static final String[] noteNames

The names of the notes in the Western scale

Constructor Detail

WesternScaleNote

public WesternScaleNote()

Method Detail

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()

nStepsBetween

public static final int nStepsBetween(WesternScaleNote note1,
                                      WesternScaleNote note2)

Returns the number of half-steps between the two given notes.

Parameters:

note1 - The first note of the interval

note2 - The second note of the interval

Returns:

The number of half-steps between the two notes.

noteToFrequency

public static final float noteToFrequency(int noteNumber)

Converts a MIDI note number to a frequency.

Parameters:

noteNumber - The note number

Returns:

The frequency

frequencyToNote

public static final int frequencyToNote(float frequency)

Converts a frequency to the nearest note number

Parameters:

frequency - The frequency

Returns:

The note number

createNote

public static final WesternScaleNote createNote(String noteString)

Given a note string, returns a new WesternScaleNote from which other information can be garnered. A note string is the note name followed by the octave; e.g. "D3" or "A#5".

Parameters:

noteString - The note string

Returns:

A WesternScaleNote or null if the note string is invalid

createNote

public static final WesternScaleNote createNote(String noteName,
                                                int octaveNumber)

Given a note name and octave, returns a WesternScaleNote from which other information can be garnered.

Parameters:

noteName - The name of the note

octaveNumber - The octave of the note.

Returns:

A new WesternScaleNote

createNote

public static final WesternScaleNote createNote(float frequency)

Create a WesternScaleNote given a frequency. It does this by converting the frequency in to a MIDI note number and using createNote(int) which returns the note. For this reason, the value of the member frequency in the returned note may not be the same as the given frequency.

Parameters:

frequency - The frequency to convert to a note.

Returns:

A WesternScaleNote

createNote

public static final WesternScaleNote createNote(int noteNumber)

Given a note number, returns a WesternScaleNote from which other information can be garnered.

Parameters:

noteNumber - A note number

Returns:

A WesternScaleNote