Detailed Description

Note - Musical note detection with MIDI output.

Converts continuous pitch (from Pitch) to discrete musical notes using 12-tone equal temperament (12-TET). Provides note-on/note-off events with velocity information based on attack strength.

Key Features:

Converts Hz to MIDI note numbers (A4 = 440 Hz = MIDI 69)
Note-on/note-off events with hysteresis for stability
Velocity calculation based on attack strength
Configurable note-on/note-off thresholds
Integration with Pitch for fundamental frequency tracking
Support for polyphonic detection (future enhancement)

Performance:

Depends on Pitch (no FFT required)
Update time: ~0.05-0.1ms per frame (lightweight decision logic)
Memory: ~100 bytes

Definition at line 32 of file note.h.

#include <note.h>

Inheritance diagram for fl::audio::detector::Note:

Collaboration diagram for fl::audio::detector::Note:

Public Types
using	NoteStartCallback = void(*)(u8 note, u8 velocity)

using	NoteVelocityCallback = void(*)(u8 note)

Public Member Functions
	Note () FL_NOEXCEPT

	Note () FL_NOEXCEPT

	Note (shared_ptr< Pitch > pitchDetector)

	Note (shared_ptr< Pitch > pitchDetector)

	~Note () FL_NOEXCEPT

	~Note () FL_NOEXCEPT override

void	fireCallbacks () override

u8	frequencyToMidiNote (float hz) const

u8	getCurrentNote () const

u8	getCurrentNote () const

float	getCurrentPitch () const

float	getCurrentPitch () const

u8	getLastVelocity () const

u8	getLastVelocity () const

const char *	getName () const override

float	getPitchBend () const

float	getPitchBend () const

shared_ptr< Pitch >	getPitchDetector () const

bool	isNoteActive () const

float	midiNoteToFrequency (u8 note) const

bool	needsFFT () const override

void	reset ()

void	reset () override

void	setMinNoteDuration (u32 ms)

void	setMinNoteDuration (u32 ms)

void	setNoteChangeThreshold (int semitones)

void	setNoteChangeThreshold (u8 semitones)

void	setNoteOffThreshold (float confidenceThreshold)

void	setNoteOffThreshold (float threshold)

void	setNoteOnThreshold (float confidenceThreshold)

void	setNoteOnThreshold (float threshold)

void	setPitchDetector (shared_ptr< Pitch > pitchDetector)

void	setVelocitySensitivity (float sensitivity)

void	setVelocitySensitivity (float sensitivity)

void	update (shared_ptr< Context > context)

void	update (shared_ptr< Context > context) override

Public Member Functions inherited from fl::audio::Detector
virtual	~Detector () FL_NOEXCEPT=default

virtual bool	needsFFTHistory () const FL_NOEXCEPT

virtual void	setSampleRate (int) FL_NOEXCEPT

Public Attributes
function_list< void(u8 note, u8 velocity)>	onNoteChange

NoteStartCallback	onNoteChange = nullptr

function_list< void(u8 note)>	onNoteOff

NoteVelocityCallback	onNoteOff = nullptr

function_list< void(u8 note, u8 velocity)>	onNoteOn

NoteStartCallback	onNoteOn = nullptr

Private Member Functions
float	calculatePitchBend (float hz, u8 note) const

float	calculatePitchBend (float hz, u8 note) const

u8	calculateVelocity (float energy, float confidence) const

u8	calculateVelocity (float energy, float confidence) const

u8	frequencyToMidiNote (float hz) const

float	midiNoteToFrequency (u8 note) const

bool	shouldTriggerNoteChange (u8 newNote, u8 currentNote) const

bool	shouldTriggerNoteChange (u8 newNote, u8 currentNote) const

bool	shouldTriggerNoteOff (float confidence, bool voiced) const

bool	shouldTriggerNoteOff (float confidence, bool voiced) const

bool	shouldTriggerNoteOn (float confidence, float pitch) const

bool	shouldTriggerNoteOn (float confidence, float pitch) const

Private Attributes
u8	mCurrentNote

float	mCurrentPitch

bool	mFireNoteChange = false

bool	mFireNoteOff = false

bool	mFireNoteOn = false

u32	mLastUpdateTime

u8	mLastVelocity

u32	mMinNoteDuration

bool	mNoteActive

u8	mNoteChangeThreshold

int	mNoteChangeThreshold

float	mNoteOffThreshold

float	mNoteOnEnergy

float	mNoteOnThreshold

u32	mNoteOnTime

bool	mOwnsPitchDetector

u8	mPendingOffNote = 0

u8	mPendingOnNote = 0

u8	mPendingOnVelocity = 0

float	mPitchBend

shared_ptr< Pitch >	mPitchDetector

float	mVelocitySensitivity

Static Private Attributes
static constexpr float	A4_FREQUENCY = 440.0f

static constexpr u8	A4_MIDI_NOTE = 69

static constexpr u8	NO_NOTE = 255

The documentation for this class was generated from the following files:

fl/audio/detector/note.h
fl/audio/detector/note_detector.h
fl/audio/detector/note.cpp.hpp

Detailed Description

Public Types

Public Member Functions

Public Attributes

Private Member Functions

Private Attributes

Static Private Attributes