MP3DecoderMini Class Reference

MP3 Decoder using https://github.com/pschatzmann/minimp3. This decoder does not provide any good results and it is not suited to decode any audio above 32000 on an ESP32. So the sample rate is limited by the MINIMP3_MAX_SAMPLE_RATE variable. More...

#include <CodecMP3Mini.h>

Inheritance diagram for MP3DecoderMini:

Public Member Functions
	~MP3DecoderMini ()
	Destroy the MP3DecoderMini object.
virtual void	addNotifyAudioChange (AudioInfoSupport &bi)
	Adds target to be notified about audio changes.
virtual AudioInfo	audioInfo ()
	provides the actual input AudioInfo
virtual AudioInfo	audioInfoOut ()
bool	begin ()
	Starts the processing.
virtual bool	begin (AudioInfo info) override
virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.
void	end ()
	Releases the reserved memory.
void	flush ()
	Decodes the last outstanding data.
Print *	getOutput ()
bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.
virtual bool	isResultPCM ()
	Returns true to indicate that the decoding result is PCM data.
virtual	operator bool ()
	checks if the class is active
virtual bool	removeNotifyAudioChange (AudioInfoSupport &bi)
	Removes a target in order not to be notified about audio changes.
virtual void	setAudioInfo (AudioInfo from) override
	for most decoders this is not needed
void	setBufferLength (int len)
void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)
virtual void	setOutput (AudioOutput &out_stream)
	Defines where the decoded result is written to.
virtual void	setOutput (AudioStream &out_stream)
	Defines where the decoded result is written to.
void	setOutput (Print &outStream)
	Defines the output Stream.
void	setSampleRateLimit (int limit)
size_t	write (const uint8_t *data, size_t len)
	Write mp3 data to decoder.

Public Attributes
int	id
	custom id to be used by application

Protected Member Functions
void	decode (int write_len)
	Process single bytes so that we can decode a full frame when it is available.
void	f32_to_s16 (float *in, int16_t *out, int num_samples)
void	notifyAudioChange (AudioInfo info)
void	provideResult (int samples)
	Provides Metadata and PCM data.
void	writeBlocking (Print *out, uint8_t *data, size_t len)

Protected Attributes
bool	active
Vector< uint8_t >	buffer
size_t	buffer_pos = 0
size_t	buffer_size = 5 * 1024
AudioInfo	info
bool	is_notify_active = true
mp3dec_t	mp3d
mp3dec_frame_info_t	mp3dec_info
Vector< AudioInfoSupport * >	notify_vector
Print *	out = nullptr
Print *	p_print = nullptr
Vector< mp3d_sample_t >	pcm
int	sample_rate_limit = 44100

Detailed Description

MP3 Decoder using https://github.com/pschatzmann/minimp3. This decoder does not provide any good results and it is not suited to decode any audio above 32000 on an ESP32. So the sample rate is limited by the MINIMP3_MAX_SAMPLE_RATE variable.

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 ( )

inlinevirtualinherited

provides the actual input AudioInfo

Implements AudioInfoSupport.

Reimplemented in CodecNOP, GGWaveDecoder, AACDecoderFDK, AACDecoderHelix, DecoderBasic, MP3DecoderHelix, MP3DecoderMAD, OpusAudioDecoder, WAVDecoder, WavIMADecoder, and OggContainerDecoder.

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.

begin() [1/2]

bool begin ( )

inlinevirtual

Starts the processing.

Reimplemented from AudioDecoder.

begin() [2/2]

virtual bool begin ( AudioInfo  info )

inlineoverridevirtualinherited

Reimplemented from AudioWriter.

end()

void end ( )

inlinevirtual

Releases the reserved memory.

Reimplemented from AudioDecoder.

isResultPCM()

virtual bool isResultPCM ( )

inlinevirtualinherited

Returns true to indicate that the decoding result is PCM data.

Reimplemented in CopyDecoder, and GGWaveDecoder.

operator bool()

virtual operator bool ( )

inlinevirtual

checks if the class is active

Implements AudioWriter.

setAudioInfo()

virtual void setAudioInfo ( AudioInfo  from )

inlineoverridevirtualinherited

for most decoders this is not needed

Implements AudioWriter.

Reimplemented in GGWaveDecoder, DecoderL8, OpusAudioDecoder, CodecNOP, AACDecoderHelix, and G7xxDecoder.

setOutput() [1/3]

virtual void setOutput ( AudioOutput &  out_stream )

inlinevirtualinherited

Defines where the decoded result is written to.

Reimplemented in ADTSDecoder, MTSDecoder, MTSDecoderTSDemux, and MetaDataFilterDecoder.

setOutput() [2/3]

virtual void setOutput ( AudioStream &  out_stream )

inlinevirtualinherited

Defines where the decoded result is written to.

Reimplemented in ADTSDecoder, MTSDecoder, MTSDecoderTSDemux, and MetaDataFilterDecoder.

setOutput() [3/3]

void setOutput ( Print &  outStream )

inlinevirtual

Defines the output Stream.

Reimplemented from AudioDecoder.

write()

size_t write ( const uint8_t *  data, size_t  len  )

inlinevirtual

Write mp3 data to decoder.

Implements AudioWriter.

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

• src/AudioTools/AudioCodecs/CodecMP3Mini.h