/**
* Calculates the frequency (Hz) for a MIDI key.
*
* @param midiKey The MIDI key. A MIDI key is an integer between 0 and 127, inclusive.
* @return A frequency in Hz corresponding to the MIDI key.
* @exception IllegalArgumentException If midiKey is not in the valid range between 0 and 127,
* inclusive.
*/
public static double midiKeyToHertz(final int midiKey) {
if (midiKey < 0 || midiKey > 127) {
LOG.warning(
"MIDI keys are defined between 0 and 127 or from "
+ midiKeyToHertz(0)
+ "Hz to "
+ midiKeyToHertz(127)
+ "Hz, MIDI KEY "
+ midiKey
+ " is out of this range.");
}
return PitchUnit.midiCentToHertz(midiKey);
}
private double convertToHertz(final double value, final PitchUnit valueUnit) {
final double hertzValue;
switch (valueUnit) {
case ABSOLUTE_CENTS:
hertzValue = PitchUnit.absoluteCentToHertz(value);
break;
case HERTZ:
hertzValue = value;
break;
case MIDI_CENT:
hertzValue = PitchUnit.midiCentToHertz(value);
break;
case MIDI_KEY:
hertzValue = PitchUnit.midiKeyToHertz((int) value);
break;
case RELATIVE_CENTS:
hertzValue = PitchUnit.relativeCentToHertz(value);
break;
default:
throw new AssertionError("Unknown pitch unit: " + getHumanName());
}
return hertzValue;
}
