VolumeMeter Class Reference

A simple class to determine the volume. You can use it as final output or as output or input in your audio chain. More...

#include <AudioStreams.h>

Inheritance diagram for VolumeMeter:

Public Member Functions
	VolumeMeter ()=default
	VolumeMeter (AudioOutput &ao)
	VolumeMeter (AudioStream &as)
	VolumeMeter (Print &print)
	VolumeMeter (Stream &stream)
virtual void	addNotifyAudioChange (AudioInfoSupport &bi)
	Adds target to be notified about audio changes.
virtual AudioInfo	audioInfo () override
	provides the actual input AudioInfo
virtual AudioInfo	audioInfoOut ()
virtual int	available () override
virtual int	availableForWrite () override
bool	begin () override
bool	begin (AudioInfo info)
void	clear ()
	Resets the actual volume.
virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.
virtual void	end ()
virtual void	flush () override
bool	isActive () const
bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.
virtual	operator bool ()
size_t	readBytes (uint8_t *data, size_t len) override
virtual size_t	readSilence (uint8_t *buffer, size_t length)
	Source to generate silence: just sets the buffer to 0.
virtual bool	removeNotifyAudioChange (AudioInfoSupport &bi)
	Removes a target in order not to be notified about audio changes.
void	setActivityCallback (ActivityCallback callback, float threshold=0.2, unsigned long duration_ms=2000)
void	setAudioInfo (AudioInfo info) override
	Defines the input AudioInfo.
void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)
void	setOutput (AudioOutput &out)
void	setOutput (Print &out) override
	Defines/Changes the output target.
void	setStream (AudioStream &io)
void	setStream (Stream &io) override
	Defines/Changes the input & output.
void	setWriteBufferSize (int size)
float	volume ()
float	volume (int channel)
float	volumeAvg ()
	Average volume of all channels.
float	volumeAvg (int channel)
	Average volume of indicated channel.
float	volumeDB ()
	Volume in db: max amplitude is 0 (range: -1000 to 0)
float	volumeDB (int channel)
	Volume of indicated channel in db: max amplitude is 0.
float	volumePercent ()
	Volume in %: max amplitude is 100.
float	volumePercent (int channel)
	Volume of indicated channel in %: max amplitude is 100.
float	volumeRatio ()
	Volume Ratio: max amplitude is 1.0.
float	volumeRatio (int channel)
	Volume Ratio of indicated channel: max amplitude is 1.0.
size_t	write (const uint8_t *data, size_t len) override
virtual size_t	write (uint8_t ch) override
virtual void	writeSilence (size_t len)
	Writes len bytes of silence (=0).

Protected Member Functions
void	commit ()
virtual int	not_supported (int out, const char *msg="")
void	notifyAudioChange (AudioInfo info)
void	refillReadBuffer ()
void	updateActivityState ()
void	updateVolume (float tmp, int j)
void	updateVolumes (const uint8_t *data, size_t len)
template<typename T >
void	updateVolumesT (const uint8_t *buffer, size_t size)

Protected Attributes
int	_timeout = 10
ActivityCallback	activity_callback = nullptr
unsigned long	activity_duration_ms = 0
bool	activity_monitoring_enabled = false
float	activity_threshold = 0.0f
float	f_volume = 0
float	f_volume_tmp = 0
unsigned long	inactive_start_time = 0
AudioInfo	info
bool	is_active = false
bool	is_notify_active = true
Vector< AudioInfoSupport * >	notify_vector
Print *	p_out = nullptr
Stream *	p_stream = nullptr
size_t	sample_count_per_channel = 0
Vector< float >	sum {0}
Vector< float >	sum_tmp {0}
RingBuffer< uint8_t >	tmp_in {0}
RingBuffer< uint8_t >	tmp_out {0}
Vector< float >	volumes {0}
Vector< float >	volumes_tmp {0}
int	write_buffer_size = MAX_SINGLE_CHARS

Detailed Description

A simple class to determine the volume. You can use it as final output or as output or input in your audio chain.

Author

Phil Schatzmann

Copyright

GPLv3

Constructor & Destructor Documentation

VolumeMeter() [1/5]

VolumeMeter ( )

default

VolumeMeter() [2/5]

VolumeMeter ( AudioStream &  as )

inline

VolumeMeter() [3/5]

VolumeMeter ( AudioOutput &  ao )

inline

VolumeMeter() [4/5]

VolumeMeter ( Print &  print )

inline

VolumeMeter() [5/5]

VolumeMeter ( Stream &  stream )

inline

Member Function Documentation

addNotifyAudioChange()

virtual void addNotifyAudioChange ( AudioInfoSupport &  bi )

inlinevirtualinherited

Adds target to be notified about audio changes.

Reimplemented in CodecNOP, EncodedAudioOutput, EncodedAudioStream, AACDecoderFDK, DecoderBasic, CodecChain, MP3DecoderHelix, MP3DecoderMAD, OggContainerDecoder, RTSPClient< TcpClient, UdpSocket >, Pipeline, and Pipeline::ModifyingStreamAdapter.

audioInfo()

virtual AudioInfo audioInfo ( )

inlineoverridevirtualinherited

provides the actual input AudioInfo

Implements AudioInfoSupport.

Reimplemented in JupyterAudioT< T >, MozziStream, TimerCallbackAudioStream, EncodedAudioStream, PureDataStream, AdapterAudioOutputToAudioStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, and InputMerge< T >.

audioInfoOut()

virtual AudioInfo audioInfoOut ( )

inlinevirtualinherited

provides the actual output AudioInfo: this is usually the same as audioInfo() unless we use a transforming stream

Reimplemented in PureDataStream, PWMAudioOutput, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, FormatConverterStream, Pipeline, ResampleStream, and ResampleStreamT< TInterpolator >.

available()

virtual int available ( )

inlineoverridevirtualinherited

Reimplemented from Stream.

Reimplemented in AudioKitStream, AudioLoRa, URLStreamBufferedT< T >, URLStreamBufferedT< ICYStream >, VBANStream, AudioStreamWrapper, LoRaStream, FaustStream< DSP >, AudioFFTBase, AudioMP34DT05, I2SCodecStream, MiniAudioStream, StdioStream, TfLiteAudioStream, A2DPStream, ESPNowStream, HammingFEC< bytecount, block_t >, HLSStreamT< URLStream >, HttpRequest, ICYStreamT< T >, URLStream, BufferedTaskStream, ReedSolomonFEC< bytecount, additional_bytes >, UDPStream, AnalogAudioArduino, AnalogAudioStream, AudioEffectStreamT< T >, Equalizer3Bands, Equalizer3BandsPerChannel, I2SStream, ReformatBaseStream, TimedStream, MemoryStream, RingBufferStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, BufferedStream, ConverterStream< T >, MeasuringStream, ProgressStream, Throttle, InputMerge< T >, CallbackStream, FilteredStream< T, TF >, FilteredStream< int16_t, int16_t >, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, CatStream, QueueStream< T >, QueueStream< uint8_t >, DynamicMemoryStream, FadeStream, FrequencyDetectorAutoCorrelation, FrequencyDetectorZeroCrossing, Pipeline, Pipeline::ModifyingStreamAdapter, VolumeStream, FileLoopT< FileType >, FileLoopT< File >, AudioBLEClient, AudioBLEClient, AudioBLEServer, and AudioBLEServer.

availableForWrite()

virtual int availableForWrite ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in AudioLoRa, UDPStream, VBANStream, AudioStreamWrapper, ConverterStream< T >, LoRaStream, EncodedAudioStream, FaustStream< DSP >, AudioFFTBase, I2SCodecStream, MiniAudioStream, StdioStream, A2DPStream, ESPNowStream, HammingFEC< bytecount, block_t >, AbstractURLStream, URLStreamESP32, ReedSolomonFEC< bytecount, additional_bytes >, AnalogAudioArduino, AnalogAudioStream, AudioEffectStreamT< T >, Equalizer3Bands, Equalizer3BandsPerChannel, I2SStream, ReformatBaseStream, TimedStream, MemoryStream, RingBufferStream, MeasuringStream, ProgressStream, Throttle, FilteredStream< T, TF >, FilteredStream< int16_t, int16_t >, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, QueueStream< T >, QueueStream< uint8_t >, DynamicMemoryStream, FadeStream, FrequencyDetectorAutoCorrelation, FrequencyDetectorZeroCrossing, Pipeline, VolumeStream, AudioBLEClient, AudioBLEClient, AudioBLEServer, and AudioBLEServer.

begin() [1/2]

bool begin ( )

inlineoverridevirtual

Reimplemented from BaseStream.

begin() [2/2]

bool begin ( AudioInfo  info )

inline

clear()

void clear ( )

inline

Resets the actual volume.

clearNotifyAudioChange()

virtual void clearNotifyAudioChange ( )

inlinevirtualinherited

Deletes all change notify subscriptions.

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

commit()

void commit ( )

inlineprotected

end()

virtual void end ( )

inlinevirtualinherited

Reimplemented in FaustStream< DSP >, AudioMP34DT05, I2SCodecStream, MozziStream, PureDataStream, SPDIFOutput, VS1053Stream, WM8960Stream, AdaptiveResamplingStream, AudioLoRa, ESPNowStream, BufferedTaskStream, URLStreamBufferedT< T >, URLStreamBufferedT< ICYStream >, Equalizer3Bands, I2SStream, AudioStreamWrapper, TimerCallbackAudioStream, FormatConverterStream, GoertzelStream, FileLoopT< FileType >, FileLoopT< File >, EqualizerNBands< SampleT, AccT, NUM_TAPS, NUM_BANDS >, LoRaStream, EncodedAudioStream, AudioFFTBase, AudioKitStream, MiniAudioStream, PortAudioStream, StdioStream, A2DPStream, HLSStreamT< URLStream >, HttpRequest, ICYStreamT< T >, URLStream, URLStreamESP32, AnalogAudioArduino, AnalogAudioStream, AudioEffectStreamT< T >, Equalizer3BandsPerChannel, ReformatBaseStream, AdapterAudioOutputToAudioStream, MemoryStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, InputMixer< T >, InputMerge< T >, CallbackStream, FilteredStream< T, TF >, FilteredStream< int16_t, int16_t >, ChannelFormatConverterStream, NumberFormatConverterStream, CatStream, QueueStream< T >, QueueStream< uint8_t >, DynamicMemoryStream, Pipeline, Pipeline::ModifyingStreamAdapter, VolumeStream, AudioBLEClient, AudioBLEClient, AudioBLEServer, AudioBLEServer, AbstractURLStream, and AudioBLEStream.

flush()

virtual void flush ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in PureDataStream, URLStreamBufferedT< T >, URLStreamBufferedT< ICYStream >, AudioStreamWrapper, ResampleStream, URLStream, BufferedTaskStream, I2SStream, MemoryStream, RingBufferStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, and BufferedStream.

isActive()

bool isActive ( ) const

inline

Get current activity state

Returns

true if active (volume above threshold), false if inactive

isNotifyActive()

bool isNotifyActive ( )

inlineinherited

Checks if the automatic AudioInfo update is active.

not_supported()

virtual int not_supported ( int  out, const char *  msg = ""  )

inlineprotectedvirtualinherited

notifyAudioChange()

void notifyAudioChange ( AudioInfo  info )

inlineprotectedinherited

operator bool()

virtual operator bool ( )

inlinevirtualinherited

Reimplemented in A2DPStream, ICYStreamT< T >, AudioBLEStream, AudioFFTBase, PortAudioStream, URLStream, I2SStream, AdapterAudioOutputToAudioStream, TimedStream, MemoryStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, and Pipeline.

readBytes()

size_t readBytes ( uint8_t *  data, size_t  len  )

inlineoverridevirtual

Reimplemented from AudioStream.

readSilence()

virtual size_t readSilence ( uint8_t *  buffer, size_t  length  )

inlinevirtualinherited

Source to generate silence: just sets the buffer to 0.

refillReadBuffer()

void refillReadBuffer ( )

inlineprotectedinherited

removeNotifyAudioChange()

virtual bool removeNotifyAudioChange ( AudioInfoSupport &  bi )

inlinevirtualinherited

Removes a target in order not to be notified about audio changes.

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

setActivityCallback()

void setActivityCallback ( ActivityCallback  callback, float  threshold = 0.2, unsigned long  duration_ms = 2000  )

inline

Set activity monitoring callback and configure threshold

Parameters

callback	Function to call when activity state changes (nullptr to disable)
threshold	Volume threshold (0.0 to 1.0) - activity detected when volume exceeds this
duration_ms	Time in milliseconds volume must be below threshold to be considered inactive

setAudioInfo()

void setAudioInfo ( AudioInfo  info )

inlineoverridevirtual

Defines the input AudioInfo.

Reimplemented from AudioStream.

setNotifyActive()

void setNotifyActive ( bool  flag )

inlineinherited

Deactivate/Reactivate automatic AudioInfo updates: (default is active)

setOutput() [1/2]

void setOutput ( AudioOutput &  out )

inline

setOutput() [2/2]

void setOutput ( Print &  out )

inlineoverridevirtual

Defines/Changes the output target.

Implements ModifyingStream.

setStream() [1/2]

void setStream ( AudioStream &  io )

inline

setStream() [2/2]

void setStream ( Stream &  in )

inlineoverridevirtual

Defines/Changes the input & output.

Implements ModifyingStream.

setWriteBufferSize()

void setWriteBufferSize ( int  size )

inlineinherited

updateActivityState()

void updateActivityState ( )

inlineprotected

updateVolume()

void updateVolume ( float  tmp, int  j  )

inlineprotected

updateVolumes()

void updateVolumes ( const uint8_t *  data, size_t  len  )

inlineprotected

updateVolumesT()

template<typename T >

void updateVolumesT ( const uint8_t *  buffer, size_t  size  )

inlineprotected

volume() [1/2]

float volume ( )

inline

Determines the volume (max amplitude). The range depends on the bits_per_sample.

volume() [2/2]

float volume ( int  channel )

inline

Determines the volume for the indicated channel. You must call the begin method to define the number of channels

volumeAvg() [1/2]

float volumeAvg ( )

inline

Average volume of all channels.

volumeAvg() [2/2]

float volumeAvg ( int  channel )

inline

Average volume of indicated channel.

volumeDB() [1/2]

float volumeDB ( )

inline

Volume in db: max amplitude is 0 (range: -1000 to 0)

volumeDB() [2/2]

float volumeDB ( int  channel )

inline

Volume of indicated channel in db: max amplitude is 0.

volumePercent() [1/2]

float volumePercent ( )

inline

Volume in %: max amplitude is 100.

volumePercent() [2/2]

float volumePercent ( int  channel )

inline

Volume of indicated channel in %: max amplitude is 100.

volumeRatio() [1/2]

float volumeRatio ( )

inline

Volume Ratio: max amplitude is 1.0.

volumeRatio() [2/2]

float volumeRatio ( int  channel )

inline

Volume Ratio of indicated channel: max amplitude is 1.0.

write() [1/2]

size_t write ( const uint8_t *  data, size_t  len  )

inlineoverridevirtual

Reimplemented from AudioStream.

write() [2/2]

virtual size_t write ( uint8_t  ch )

inlineoverridevirtualinherited

Reimplemented in MemoryStream, AudioStreamWrapper, BufferedTaskStream, RingBufferStream, BufferedStream, and URLStream.

writeSilence()

virtual void writeSilence ( size_t  len )

inlinevirtualinherited

Writes len bytes of silence (=0).

Member Data Documentation

_timeout

int _timeout = 10

protectedinherited

activity_callback

ActivityCallback activity_callback = nullptr

protected

activity_duration_ms

unsigned long activity_duration_ms = 0

protected

activity_monitoring_enabled

bool activity_monitoring_enabled = false

protected

activity_threshold

float activity_threshold = 0.0f

protected

f_volume

float f_volume = 0

protected

f_volume_tmp

float f_volume_tmp = 0

protected

inactive_start_time

unsigned long inactive_start_time = 0

protected

info

AudioInfo info

protectedinherited

is_active

bool is_active = false

protected

is_notify_active

bool is_notify_active = true

protectedinherited

notify_vector

Vector<AudioInfoSupport*> notify_vector

protectedinherited

p_out

Print* p_out = nullptr

protected

p_stream

Stream* p_stream = nullptr

protected

sample_count_per_channel

size_t sample_count_per_channel = 0

protected

sum

Vector<float> sum {0}

protected

sum_tmp

Vector<float> sum_tmp {0}

protected

tmp_in

RingBuffer<uint8_t> tmp_in {0}

protectedinherited

tmp_out

RingBuffer<uint8_t> tmp_out {0}

protectedinherited

volumes

Vector<float> volumes {0}

protected

volumes_tmp

Vector<float> volumes_tmp {0}

protected

write_buffer_size

int write_buffer_size = MAX_SINGLE_CHARS

protectedinherited

---

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

• src/AudioTools/CoreAudio/AudioStreams.h