G729Encoder Class Reference

G.729 encoder using the bcg729 library. More...

#include <CodecG729.h>

Inheritance diagram for G729Encoder:

Public Member Functions
	G729Encoder (bool is_vad_enabled=false)
AudioInfo	audioInfo () override
	provides the actual input AudioInfo
virtual AudioInfo	audioInfoOut ()
bool	begin () override
virtual bool	begin (AudioInfo info)
void	end () override
virtual uint32_t	frameDurationUs ()
	Optional rtsp function: provide the frame duration in microseconds.
const char *	mime () override
	Provides the mime type of the encoded result.
	operator bool () override
virtual uint16_t	samplesPerFrame ()
	Optional rtsp function: provide samples per the frame.
void	setAudioInfo (AudioInfo info) override
	Defines the sample rate, number of channels and bits per sample.
void	setOutput (Print &out_stream) override
	Default output assignment (encoders may override to store Print reference)
void	setVADEnabled (bool enabled)
size_t	write (const uint8_t *data, size_t len) override

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

Protected Attributes
size_t	buffer_pos = 0
bcg729EncoderChannelContextStruct *	encoder_ctx = nullptr
AudioInfo	info
Vector< uint8_t >	input_buffer
bool	is_active = false
Print *	p_print = nullptr
Vector< uint8_t >	result_buffer
bool	vad_enabled = false

Detailed Description

G.729 encoder using the bcg729 library.

Accepts 16-bit PCM samples at 8 000 Hz (mono) and writes compressed G.729 frames to the configured output. Frames are produced every 80 input samples (10 ms):

• Normal speech frame : 10 bytes
• SID / comfort-noise : 2 bytes (only when VAD is enabled)

VAD (Voice Activity Detection) is enabled by default; pass false to the constructor to disable it and always produce 10-byte speech frames.

Input must be exactly 8 000 Hz / mono / 16-bit PCM. Passing any other AudioInfo via setAudioInfo() logs an error and the fixed format is enforced.

Bitrate: 8 kbps (10 bytes × 8 bits/byte ÷ 0.01 s) which gives 1 kbytes/s Compression ratio: 16:1 (w/o SID frame)

Note

Requires https://github.com/pschatzmann/codec-bcg729

Author

Phil Schatzmann

Copyright

GPLv3

Constructor & Destructor Documentation

G729Encoder()

G729Encoder ( bool  is_vad_enabled = false )

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, and ResampleStreamT< TInterpolator >.

begin() [1/2]

bool begin ( )

inlineoverridevirtual

Implements AudioWriter.

begin() [2/2]

virtual bool begin ( AudioInfo  info )

inlinevirtualinherited

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

end()

void end ( )

inlineoverridevirtual

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.

mime()

const char * mime ( )

inlineoverridevirtual

Provides the mime type of the encoded result.

Implements AudioEncoder.

operator bool()

operator bool ( )

inlineoverridevirtual

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.

setAudioInfo()

void setAudioInfo ( AudioInfo  from )

inlineoverridevirtual

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

Reimplemented from AudioEncoder.

setOutput()

void setOutput ( Print &  out_stream )

inlineoverridevirtual

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

Reimplemented from AudioEncoder.

setVADEnabled()

void setVADEnabled ( bool  enabled )

inline

write()

size_t write ( const uint8_t *  data, size_t  len  )

inlineoverridevirtual

Implements AudioWriter.

writeBlocking()

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

inlineprotectedinherited

Member Data Documentation

buffer_pos

size_t buffer_pos = 0

protected

encoder_ctx

bcg729EncoderChannelContextStruct* encoder_ctx = nullptr

protected

info

AudioInfo info

protectedinherited

input_buffer

Vector<uint8_t> input_buffer

protected

is_active

bool is_active = false

protected

p_print

Print* p_print = nullptr

protected

result_buffer

Vector<uint8_t> result_buffer

protected

vad_enabled

bool vad_enabled = false

protected

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

• src/AudioTools/AudioCodecs/CodecG729.h