PDMMonoStreamT< T > Class Template Reference

Applies low pass filter to a decimated pdm signal to convert it to pcm. More...

#include <PDMStream.h>

Inheritance diagram for PDMMonoStreamT< T >:

Public Member Functions
	PDMMonoStreamT (Stream &in)
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 ()
AudioInfo	audioInfoPDM ()
int	available ()
virtual int	availableForWrite () override
bool	begin ()
bool	begin (AudioInfo info)
virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.
int	decimation ()
virtual void	end ()
virtual void	flush () override
bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.
virtual	operator bool ()
size_t	readBytes (uint8_t *data, size_t len)
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.
virtual void	setAudioInfo (AudioInfo newInfo) override
	Defines the input AudioInfo.
void	setDecimationFactor (int factor)
template<size_t B>
void	setFilterValues (const T(&b)[B])
void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)
virtual 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
constexpr int8_t	bitsPerSample ()
virtual int	not_supported (int out, const char *msg="")
void	notifyAudioChange (AudioInfo info)
void	refillReadBuffer ()

Protected Attributes
int	_timeout = 10
float	coef [19]
int	decimation_factor = sizeof(T) * 2
DecimationStreamExt< T >	decimation_stream
FIR< float >	fir {coef}
FilteredStream< T, float >	in_filtered {decimation_stream, 1}
AudioInfo	info
bool	is_notify_active = true
Vector< AudioInfoSupport * >	notify_vector
RingBuffer< uint8_t >	tmp_in {0}
RingBuffer< uint8_t >	tmp_out {0}

Detailed Description

template<typename T>
class audio_tools::PDMMonoStreamT< T >

Applies low pass filter to a decimated pdm signal to convert it to pcm.

Author

Phil Schatzmann

Copyright

GPLv3

Member Function Documentation

addNotifyAudioChange()

virtual void addNotifyAudioChange ( AudioInfoSupport &  bi )

inlinevirtualinherited

Adds target to be notified about audio changes.

Reimplemented in CodecNOP, MP3DecoderMAD, EncodedAudioOutput, EncodedAudioStream, AACDecoderFDK, DecoderBasic, MP3DecoderHelix, OggContainerDecoder, Pipeline, and Pipeline::ModifyingStreamAdapter.

audioInfo()

virtual AudioInfo audioInfo ( )

inlineoverridevirtualinherited

provides the actual input AudioInfo

Implements AudioInfoSupport.

Reimplemented in JupyterAudioT< T >, MozziStream, TimerCallbackAudioStream, 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, and ResampleStream.

available()

template<typename T >

int available ( )

inlinevirtual

Reimplemented from BaseStream.

availableForWrite()

virtual int availableForWrite ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in UDPStream, A2DPStream, AudioFFTBase, I2SCodecStream, AbstractURLStream, URLStreamESP32, I2SStream, MeasuringStream, ProgressStream, and VolumeStream.

begin()

template<typename T >

bool begin ( )

inlinevirtual

Reimplemented from BaseStream.

end()

virtual void end ( )

inlinevirtualinherited

Reimplemented in FaustStream< DSP >, HLSStreamT< URLStream >, I2SCodecStream, VS1053Stream, WM8960Stream, ESPNowStream, I2SStream, TimerCallbackAudioStream, QueueStream< T >, QueueStream< uint8_t >, AudioFFTBase, AudioKitStream, AnalogAudioStream, HttpRequest, ICYStreamT< T >, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, InputMixer< T >, InputMerge< T >, and Pipeline.

flush()

virtual void flush ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in ResampleStream, BufferedTaskStream, and BufferedStream.

operator bool()

virtual operator bool ( )

inlinevirtualinherited

Reimplemented in A2DPStream, Pipeline, I2SStream, and MemoryStream.

readBytes()

template<typename T >

size_t readBytes ( uint8_t *  data, size_t  len  )

inlinevirtual

Reimplemented from AudioStream.

setAudioInfo()

virtual void setAudioInfo ( AudioInfo  info )

inlineoverridevirtualinherited

Defines the input AudioInfo.

Implements AudioInfoSupport.

Reimplemented in VS1053Stream, WM8960Stream, I2SBitBang, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, VolumeStream, MiniAudioStream, PortAudioStream, I2SCodecStream, MozziStream, SPDIFOutput, AudioLoRa, AnalogAudioStream, I2SStream, MeasuringStream, VolumeMeter, TimerCallbackAudioStream, AudioBLEStream, LoRaStream, AudioFFTBase, AudioKitStream, VBANStream, AnalogAudioArduino, Equalizer3Bands, AdapterAudioOutputToAudioStream, TimedStream, ProgressStream, FormatConverterStream, FadeStream, Pipeline::ModifyingStreamAdapter, PureDataStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, Pipeline, and ResampleStream.

write() [1/2]

virtual size_t write ( const uint8_t *  data, size_t  len  )

inlineoverridevirtualinherited

Implements BaseStream.

Reimplemented in I2SCodecStream, MozziStream, SPDIFOutput, I2SStream, A2DPStream, FaustStream< DSP >, AudioFFTBase, TfLiteAudioStream, VS1053Stream, AnalogAudioStream, AudioEffectStreamT< T >, BufferedTaskStream, TimedStream, BufferedStream, MeasuringStream, ProgressStream, VolumeStream, TfLiteAudioStreamBase, and AnalogDriverESP32V2::IO16Bit.

write() [2/2]

virtual size_t write ( uint8_t  ch )

inlineoverridevirtualinherited

Reimplemented in BufferedTaskStream, and BufferedStream.

Member Data Documentation

coef

template<typename T >

float coef[19]

protected

Initial value:

= {
      -0.000704420658475743, -0.000537879918926308, 0.004114637509913062,
      -0.012685775806621488, 0.027889173789107543,  -0.049285026985058301,
      0.074005079283040689,  -0.097330704866957815, 0.114052040962871595,
      0.880965753382213723,  0.114052040962871595,  -0.097330704866957843,
      0.074005079283040717,  -0.049285026985058301, 0.027889173789107550,
      -0.012685775806621504, 0.004114637509913064,  -0.000537879918926308,
      -0.000704420658475743}

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

• src/AudioTools/Sandbox/PDMStream.h