EncoderL8 Class Reference

EncoderL8s - Condenses 16 bit PCM data stream to 8 bits data. Most microcontrollers can not process 8 bit audio data directly. 8 bit data however is very memory efficient and helps if you need to store audio on constrained resources. This encoder translates 16bit data into 8bit data. By default the encoded data is represented as uint8_t, so the values are from 0 to 255. More...

#include <CodecL8.h>

Inheritance diagram for EncoderL8:

Public Member Functions
	EncoderL8 (bool isSigned=false)
	EncoderL8 (Print &out)
AudioInfo	audioInfo ()
	provides the actual input AudioInfo
virtual AudioInfo	audioInfoOut ()
bool	begin () override
	starts the processing using the actual RAWAudioInfo
virtual bool	begin (AudioInfo info)
bool	begin (Print &out)
	starts the processing
int16_t	convertSample (int16_t sample)
void	end () override
	stops the processing
bool	isOpen ()
const char *	mime () override
	Provides "audio/pcm".
	operator bool () override
void	setAudioInfo (AudioInfo from) override
	Defines the sample rate, number of channels and bits per sample.
void	setOutput (Print &out_stream) override
	Defines the output Stream.
void	setSigned (bool isSigned)
	By default the encoded values are unsigned, but can change them to signed.
size_t	write (const uint8_t *data, size_t len) override
	Writes PCM data to be encoded as RAW.

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

Protected Attributes
Vector< int8_t >	buffer
AudioInfo	info
bool	is_open
bool	is_signed = false
Print *	p_print = nullptr

Detailed Description

EncoderL8s - Condenses 16 bit PCM data stream to 8 bits data. Most microcontrollers can not process 8 bit audio data directly. 8 bit data however is very memory efficient and helps if you need to store audio on constrained resources. This encoder translates 16bit data into 8bit data. By default the encoded data is represented as uint8_t, so the values are from 0 to 255.

Author

Phil Schatzmann

Copyright

GPLv3

Member Function Documentation

audioInfo()

AudioInfo audioInfo ( )

inlinevirtualinherited

provides the actual input AudioInfo

Implements AudioInfoSupport.

Reimplemented in CodecNOP, and BinaryContainerEncoder.

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 ( )

inlineoverridevirtual

starts the processing using the actual RAWAudioInfo

Implements AudioWriter.

begin() [2/2]

virtual bool begin ( AudioInfo  info )

inlinevirtualinherited

Reimplemented in AACEncoderFDK.

end()

void end ( )

inlineoverridevirtual

stops the processing

Implements AudioWriter.

mime()

const char * mime ( )

inlineoverridevirtual

Provides "audio/pcm".

Implements AudioEncoder.

operator bool()

operator bool ( )

inlineoverridevirtual

Implements AudioWriter.

setAudioInfo()

void setAudioInfo ( AudioInfo  from )

inlineoverridevirtualinherited

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

Implements AudioWriter.

Reimplemented in MP3EncoderLAME, EncoderBasic, FLACEncoder, OpusAudioEncoder, WAVEncoder, CodecNOP, G7xxEncoder, BinaryContainerEncoder, and OggContainerEncoder.

setOutput()

void setOutput ( Print &  out_stream )

inlineoverridevirtual

Defines the output Stream.

Implements AudioWriter.

write()

size_t write ( const uint8_t *  data, size_t  len  )

inlineoverridevirtual

Writes PCM data to be encoded as RAW.

Implements AudioWriter.

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

• src/AudioTools/AudioCodecs/CodecL8.h