AACEncoderVO Class Reference

AAC Encoder based on the VisualOn vo-aacenc implementation (https://github.com/pschatzmann/codec-vo-aacenc). More...

#include <CodecAACVO.h>

Inheritance diagram for AACEncoderVO:

Public Member Functions
	AACEncoderVO ()=default
	AACEncoderVO (Print &out_stream)
	~AACEncoderVO () override
AudioInfo	audioInfo () override
	provides the actual input AudioInfo
virtual AudioInfo	audioInfoOut ()
bool	begin () override
bool	begin (AudioInfo info) override
VOAACEncoder *	driver ()
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	setAdts (bool enabled)
	Defines if ADTS headers are generated.
void	setAudioInfo (AudioInfo from) override
	Defines the sample rate, number of channels and bits per sample.
void	setBitrate (uint32_t bps)
void	setOutput (Print &out_stream) override
	Defines the output stream.
void	setOutputBufferSize (size_t len)
	Defines max encoded output frame size.
size_t	write (const uint8_t *data, size_t len) override

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

Static Protected Member Functions
static uint32_t	defaultBitrate (uint32_t sample_rate, int channels)

Protected Attributes
bool	active = false
uint32_t	bitrate = 128000
bool	bitrate_set = false
VOAACEncoder	enc
size_t	frame_bytes = 0
AudioInfo	info
Vector< uint8_t >	out_buffer {0}
size_t	output_buffer_size = 2048
Print *	p_print = nullptr
Vector< uint8_t >	pcm_buffer {0}
size_t	pcm_pos = 0
bool	use_adts = true

Detailed Description

AAC Encoder based on the VisualOn vo-aacenc implementation (https://github.com/pschatzmann/codec-vo-aacenc).

The encoder consumes PCM in blocks of 1024 samples per channel, so this class buffers arbitrary write sizes and encodes full frames automatically.

Author

Phil Schatzmann

Copyright

GPLv3

Constructor & Destructor Documentation

AACEncoderVO() [1/2]

AACEncoderVO ( )

default

AACEncoderVO() [2/2]

AACEncoderVO ( Print &  out_stream )

inline

~AACEncoderVO()

~AACEncoderVO ( )

inlineoverride

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]

bool begin ( AudioInfo  info )

inlineoverridevirtual

Reimplemented from AudioWriter.

defaultBitrate()

static uint32_t defaultBitrate ( uint32_t  sample_rate, int  channels  )

inlinestaticprotected

Scales VOAAC_DEFAULT_BITRATE (defined for 16 bit stereo @ 44100 Hz) by sample rate and channel count.

driver()

VOAACEncoder * driver ( )

inline

encodeFrame()

bool encodeFrame ( )

inlineprotected

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.

samplesPerFrame()

virtual uint16_t samplesPerFrame ( )

inlinevirtualinherited

Optional rtsp function: provide samples per the frame.

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

setAdts()

void setAdts ( bool  enabled )

inline

Defines if ADTS headers are generated.

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, and MetaDataFilterEncoder.

setBitrate()

void setBitrate ( uint32_t  bps )

inline

Defines target bitrate in bps. If not called, the bitrate is derived from VOAAC_DEFAULT_BITRATE, scaled by the sample rate and channel count.

setOutput()

void setOutput ( Print &  out_stream )

inlineoverridevirtual

Defines the output stream.

Reimplemented from AudioEncoder.

setOutputBufferSize()

void setOutputBufferSize ( size_t  len )

inline

Defines max encoded output frame size.

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

active

bool active = false

protected

bitrate

uint32_t bitrate = 128000

protected

bitrate_set

bool bitrate_set = false

protected

enc

VOAACEncoder enc

protected

frame_bytes

size_t frame_bytes = 0

protected

info

AudioInfo info

protectedinherited

out_buffer

Vector<uint8_t> out_buffer {0}

protected

output_buffer_size

size_t output_buffer_size = 2048

protected

p_print

Print* p_print = nullptr

protected

pcm_buffer

Vector<uint8_t> pcm_buffer {0}

protected

pcm_pos

size_t pcm_pos = 0

protected

use_adts

bool use_adts = true

protected

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

• src/AudioTools/AudioCodecs/CodecAACVO.h