SBCEncoder Class Reference

Encoder for SBC - Depends on https://github.com/pschatzmann/codec-sbc. Inspired by sbcenc.c. More...

#include <CodecSBC.h>

Inheritance diagram for SBCEncoder:

Public Member Functions
	SBCEncoder (int subbands=8, int blocks=16, int bitpool=32, int allocation_method=SBC_AM_LOUDNESS)
AudioInfo	audioInfo () override
	provides the actual input AudioInfo
virtual AudioInfo	audioInfoOut ()
bool	begin ()
	Restarts the processing.
virtual bool	begin (AudioInfo info)
int	bytesCompressed ()
int	bytesUncompressed ()
virtual void	end ()
	Ends the processing.
virtual uint32_t	frameDurationUs ()
	Optional rtsp function: provide the frame duration in microseconds.
virtual int	frameSize ()
virtual const char *	mime ()
	Provides the mime type of the encoded result.
	operator bool ()
virtual uint16_t	samplesPerFrame ()
	Optional rtsp function: provide samples per the frame.
void	setAllocationMethod (int allocation_method)
	Defines the allocation method: Use SBC_AM_LOUDNESS, SBC_AM_SNR.
void	setAudioInfo (AudioInfo from) override
	Defines the sample rate, number of channels and bits per sample.
void	setBitpool (int bitpool)
	Defines the bitpool (2-86?)
void	setBlocks (int blocks)
	Defines the number of blocks: valid values (4,8,12,16)
virtual void	setOutput (Print &out_stream)
	Default output assignment (encoders may override to store Print reference)
void	setSubbands (int subbands)
	Defines the subbands: Use 4 or 8.
virtual size_t	write (const uint8_t *data, size_t len)

Protected Member Functions
int	codeSize ()
	Provides the uncompressed length (of the PCM data) in bytes.
int	frameLength ()
	Provides the compressed length in bytes (after encoding)
void	processByte (uint8_t byte)
bool	setup ()
	Determines audio information and calls sbc_init;.
void	writeBlocking (Print *out, uint8_t *data, size_t len)

Protected Attributes
int	allocation_method
int	bitpool = 32
int	blocks = 4
Vector< uint8_t >	buffer {0}
int	buffer_pos = 0
int	current_codesize = 0
AudioInfo	info
bool	is_active = false
bool	is_first = true
Print *	p_print = nullptr
Vector< uint8_t >	result_buffer {0}
sbc_t	sbc
int	subbands = 4

Detailed Description

Encoder for SBC - Depends on https://github.com/pschatzmann/codec-sbc. Inspired by sbcenc.c.

Author

Phil Schatzmann

Copyright

GPLv3

Constructor & Destructor Documentation

SBCEncoder()

SBCEncoder ( int  subbands = 8, int  blocks = 16, int  bitpool = 32, int  allocation_method = SBC_AM_LOUDNESS  )

inline

Member Function Documentation

audioInfo()

AudioInfo audioInfo ( )

inlineoverridevirtualinherited

provides the actual input AudioInfo

Implements AudioInfoSupport.

Reimplemented in CodecNOP, MP3EncoderShine, BinaryContainerEncoder, and MP3ParserEncoder.

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, ResampleStreamT< TInterpolator >, and SupportedRatesStream.

begin() [1/2]

bool begin ( )

inlinevirtual

Restarts the processing.

Implements AudioWriter.

begin() [2/2]

virtual bool begin ( AudioInfo  info )

inlinevirtualinherited

Reimplemented in OpusOggEncoder, OggContainerEncoder, DecoderBasic, AudioDecoder, AACEncoderFDK, AACEncoderVO, OggContainerDecoder, and MetaDataFilterEncoder.

bytesCompressed()

int bytesCompressed ( )

inline

bytesUncompressed()

int bytesUncompressed ( )

inline

codeSize()

int codeSize ( )

inlineprotected

Provides the uncompressed length (of the PCM data) in bytes.

end()

virtual void end ( )

inlinevirtual

Ends the processing.

Implements AudioWriter.

frameDurationUs()

virtual uint32_t frameDurationUs ( )

inlinevirtualinherited

Optional rtsp function: provide the frame duration in microseconds.

Reimplemented in ADPCMEncoder, MP3EncoderShine, OpusOggEncoder, MP3ParserEncoder, and MetaDataFilterEncoder.

frameLength()

int frameLength ( )

inlineprotected

Provides the compressed length in bytes (after encoding)

frameSize()

virtual int frameSize ( )

inlinevirtualinherited

Optional rtsp function: provide the encoded size (in bytes) of one frame, once known (e.g. after the encoder has seen real data). Lets an RTSPFormat size its RTP fragments to match one frame instead of a fixed guess, so throughput actually tracks frameDurationUs() - a fragment size covering several frames' worth of bytes sent at one-frame timing overruns real-time bandwidth and, over UDP (no flow control), causes packet loss. Returns 0 if not yet known/not applicable (fixed-frame-size codecs have no need to override this).

Reimplemented in ADPCMEncoder, EncoderALAC, AMRNBEncoder, AMRWBEncoder, and MP3ParserEncoder.

mime()

virtual const char * mime ( )

inlinevirtual

Provides the mime type of the encoded result.

Implements AudioEncoder.

operator bool()

operator bool ( )

inlinevirtual

Implements AudioWriter.

processByte()

void processByte ( uint8_t  byte )

inlineprotected

samplesPerFrame()

virtual uint16_t samplesPerFrame ( )

inlinevirtualinherited

Optional rtsp function: provide samples per the frame.

Reimplemented in OpusAudioEncoder, OpusMultiStreamAudioEncoder, MP3EncoderShine, MP3ParserEncoder, and MetaDataFilterEncoder.

setAllocationMethod()

void setAllocationMethod ( int  allocation_method )

inline

Defines the allocation method: Use SBC_AM_LOUDNESS, SBC_AM_SNR.

setAudioInfo()

void setAudioInfo ( AudioInfo  from )

inlineoverridevirtualinherited

Defines the sample rate, number of channels and bits per sample.

Implements AudioWriter.

Reimplemented in MP3EncoderLAME, EncoderBasic, CodecChain, DSFEncoder, FLACEncoder, MP3EncoderShine, OpusAudioEncoder, OpusMultiStreamAudioEncoder, WAVEncoder, CodecNOP, G7xxEncoder, G729Encoder, BinaryContainerEncoder, OggContainerEncoder, OSCContainerEncoder, H264RtpEncoder, JPEGRtpEncoder, and MetaDataFilterEncoder.

setBitpool()

void setBitpool ( int  bitpool )

inline

Defines the bitpool (2-86?)

setBlocks()

void setBlocks ( int  blocks )

inline

Defines the number of blocks: valid values (4,8,12,16)

setOutput()

virtual void setOutput ( Print &  out_stream )

inlinevirtual

Default output assignment (encoders may override to store Print reference)

Reimplemented from AudioEncoder.

setSubbands()

void setSubbands ( int  subbands )

inline

Defines the subbands: Use 4 or 8.

setup()

bool setup ( )

inlineprotected

Determines audio information and calls sbc_init;.

write()

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

inlinevirtual

Implements AudioWriter.

writeBlocking()

void writeBlocking ( Print *  out, uint8_t *  data, size_t  len  )

inlineprotectedinherited

Member Data Documentation

allocation_method

int allocation_method

protected

bitpool

int bitpool = 32

protected

blocks

int blocks = 4

protected

buffer

Vector<uint8_t> buffer {0}

protected

buffer_pos

int buffer_pos = 0

protected

current_codesize

int current_codesize = 0

protected

info

AudioInfo info

protectedinherited

is_active

bool is_active = false

protected

is_first

bool is_first = true

protected

p_print

Print* p_print = nullptr

protected

result_buffer

Vector<uint8_t> result_buffer {0}

protected

sbc

sbc_t sbc

protected

subbands

int subbands = 4

protected

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

• src/AudioTools/AudioCodecs/CodecSBC.h