StreamingDecoderAdapter Class Reference

Converts any AudioDecoder to a StreamingDecoder. More...

#include <StreamingDecoder.h>

Inheritance diagram for StreamingDecoderAdapter:

Public Member Functions
	StreamingDecoderAdapter (AudioDecoder &decoder, const char *mimeStr, int copySize=DEFAULT_BUFFER_SIZE)
	Constructor.
virtual void	addNotifyAudioChange (AudioInfoSupport &bi)
	Adds target to be notified about audio changes.
AudioInfo	audioInfo () override
	Provides the audio information.
virtual AudioInfo	audioInfoOut ()
bool	begin () override
	Starts the processing.
virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.
virtual bool	copy () override
	Process a single read operation - to be called in the loop.
bool	copyAll ()
	Process all available data.
void	end () override
	Releases the reserved memory.
bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.
const char *	mime () override
	Provides the MIME type.
virtual	operator bool () override
	Checks if the class is active.
virtual bool	removeNotifyAudioChange (AudioInfoSupport &bi)
	Removes a target in order not to be notified about audio changes.
bool	resize (size_t bufferSize)
	Adjust the buffer size.
void	setInput (Stream &inStream)
	Stream Interface: Decode directly by taking data from the stream.
void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)
virtual void	setOutput (AudioOutput &out_stream)
	Defines the output streams and register to be notified.
virtual void	setOutput (AudioStream &out_stream)
	Defines the output streams and register to be notified.
void	setOutput (Print &out_stream) override
	Defines the output Stream.

Protected Member Functions
void	notifyAudioChange (AudioInfo info)
size_t	readBytes (uint8_t *data, size_t len) override
	Reads bytes from the input stream.
void	setAudioInfo (AudioInfo newInfo) override
	Defines the input AudioInfo.

Protected Attributes
Vector< uint8_t >	buffer {0}
	Internal buffer for data transfer.
AudioInfo	info
bool	is_notify_active = true
const char *	mime_str = nullptr
	MIME type string.
Vector< AudioInfoSupport * >	notify_vector
AudioDecoder *	p_decoder = nullptr
	Wrapped AudioDecoder instance.
Stream *	p_input = nullptr
	Input stream for encoded audio data.
Print *	p_print = nullptr
	Output stream for decoded PCM data.

Detailed Description

Converts any AudioDecoder to a StreamingDecoder.

This adapter class allows you to use any existing AudioDecoder with the StreamingDecoder interface. It handles the conversion between the write-based AudioDecoder API and the stream-based StreamingDecoder API by using an internal buffer.

Note

The adapter reads data from the input stream into a buffer, then feeds that data to the wrapped AudioDecoder using its write() method.

Author

Phil Schatzmann

Copyright

GPLv3

Constructor & Destructor Documentation

StreamingDecoderAdapter()

StreamingDecoderAdapter ( AudioDecoder &  decoder, const char *  mimeStr, int  copySize = DEFAULT_BUFFER_SIZE  )

inline

Constructor.

Parameters

decoder	The AudioDecoder to wrap
mimeStr	The MIME type string for this decoder
copySize	Buffer size for data transfer (default: DEFAULT_BUFFER_SIZE)

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()

AudioInfo audioInfo ( )

inlineoverridevirtual

Provides the audio information.

Delegates to the wrapped decoder's audioInfo() method.

Returns

AudioInfo from the wrapped decoder

Implements StreamingDecoder.

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 MP3EncoderShine, PureDataStream, PWMAudioOutput< PWMDriverT >, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, FormatConverterStream, Pipeline, ResampleStream, and ResampleStreamT< TInterpolator >.

begin()

bool begin ( )

inlineoverridevirtual

Starts the processing.

Initializes the wrapped decoder.

Returns

true if initialization was successful, false otherwise

Implements StreamingDecoder.

clearNotifyAudioChange()

virtual void clearNotifyAudioChange ( )

inlinevirtualinherited

Deletes all change notify subscriptions.

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

copy()

virtual bool copy ( )

inlineoverridevirtual

Process a single read operation - to be called in the loop.

Reads data from the input stream into the internal buffer, then feeds it to the wrapped AudioDecoder for processing.

Returns

true if data was processed successfully, false otherwise

Implements StreamingDecoder.

copyAll()

bool copyAll ( )

inlineinherited

Process all available data.

Convenience method that calls copy() repeatedly until all available data has been processed.

Returns

true if any data was processed, false if no data was available

end()

void end ( )

inlineoverridevirtual

Releases the reserved memory.

Calls end() on the wrapped decoder to clean up resources.

Implements StreamingDecoder.

isNotifyActive()

bool isNotifyActive ( )

inlineinherited

Checks if the automatic AudioInfo update is active.

mime()

const char * mime ( )

inlineoverridevirtual

Provides the MIME type.

Returns the MIME type that was defined in the constructor.

Returns

MIME type string

Implements StreamingDecoder.

notifyAudioChange()

void notifyAudioChange ( AudioInfo  info )

inlineprotectedinherited

operator bool()

virtual operator bool ( )

inlineoverridevirtual

Checks if the class is active.

Returns

true if the wrapped decoder is active, false otherwise

Implements StreamingDecoder.

readBytes()

size_t readBytes ( uint8_t *  data, size_t  len  )

inlineoverrideprotectedvirtual

Reads bytes from the input stream.

Parameters

data	Buffer to store the read data
len	Maximum number of bytes to read

Returns

Number of bytes actually read

Implements StreamingDecoder.

removeNotifyAudioChange()

virtual bool removeNotifyAudioChange ( AudioInfoSupport &  bi )

inlinevirtualinherited

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

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

resize()

bool resize ( size_t  bufferSize )

inline

Adjust the buffer size.

Changes the internal buffer size. The existing content of the buffer is lost!

Parameters

bufferSize

New buffer size in bytes

setAudioInfo()

void setAudioInfo ( AudioInfo  info )

inlineoverrideprotectedvirtualinherited

Defines the input AudioInfo.

Implements AudioInfoSupport.

setInput()

void setInput ( Stream &  inStream )

inlineinherited

Stream Interface: Decode directly by taking data from the stream.

This is more efficient than feeding the decoder with write: just call copy() in the loop to process data from the input stream.

Parameters

inStream

The input stream containing encoded audio data

setNotifyActive()

void setNotifyActive ( bool  flag )

inlineinherited

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

setOutput() [1/3]

virtual void setOutput ( AudioOutput &  out_stream )

inlinevirtualinherited

Defines the output streams and register to be notified.

Sets the output stream and registers for audio info change notifications.

Parameters

out_stream

The AudioOutput to write decoded audio data to

Reimplemented in MultiStreamingDecoder.

setOutput() [2/3]

virtual void setOutput ( AudioStream &  out_stream )

inlinevirtualinherited

Defines the output streams and register to be notified.

Sets the output stream and registers for audio info change notifications.

Parameters

out_stream

The AudioStream to write decoded audio data to

Reimplemented in MultiStreamingDecoder.

setOutput() [3/3]

void setOutput ( Print &  out_stream )

inlineoverridevirtual

Defines the output Stream.

Sets the output stream for the wrapped decoder.

Parameters

out_stream

The output stream for decoded audio data

Reimplemented from StreamingDecoder.

Member Data Documentation

buffer

Vector<uint8_t> buffer {0}

protected

Internal buffer for data transfer.

info

AudioInfo info

protectedinherited

is_notify_active

bool is_notify_active = true

protectedinherited

mime_str

const char* mime_str = nullptr

protected

MIME type string.

notify_vector

Vector<AudioInfoSupport*> notify_vector

protectedinherited

p_decoder

AudioDecoder* p_decoder = nullptr

protected

Wrapped AudioDecoder instance.

p_input

Stream* p_input = nullptr

protectedinherited

Input stream for encoded audio data.

p_print

Print* p_print = nullptr

protectedinherited

Output stream for decoded PCM data.

---

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

• src/AudioTools/AudioCodecs/StreamingDecoder.h