Audio Decoder. More...

#include <codec_audio.h>

Public Member Functions
	cAudioDecoder (cSoftHdAudio *)
	Create a new audio decoder for the given audio context.

	~cAudioDecoder (void)

void	Open (AVCodecID, AVCodecParameters *=nullptr, AVRational={ .num=1,.den=90000 })
	Open and initiate the audio decoder.

void	Close (void)
	Close the audio decoder.

void	Decode (const AVPacket *)
	Forward an audio packet either to the decoder or passthrough.

void	FlushBuffers (void)
	Flush the audio decoder buffers.

void	SetPassthroughMask (int)
	Set audio pass-through mask.

AVCodecID	GetCodecId () const

Private Member Functions
bool	OpenSpdifMuxer (AVCodecID, int)
	Open the spdif muxer.

void	CloseSpdifMuxer (void)
	Close the spdif muxer and free the resources.

const std::vector< uint8_t > &	BuildIEC61937 (const AVPacket *)
	Prepend an IEC61937 header to the raw audio data by sending the avpkt to the spdif muxer.

bool	ShouldTryPassthrough (void)
	Test, if passthrough audio should be tried.

int	Passthrough (const AVPacket *)
	Passthrough audio data.

void	DecodePCM (const AVPacket *)
	Decode an audio packet.

int	CheckUpdateFormat (bool)
	Handle audio format changes and setup audio, if format changed.

Static Private Member Functions
static int	SpdifWriteCallback (void , uint8_t , int)
	Callback for the spdif muxer.

Private Attributes
cSoftHdAudio *	m_pAudio
	audio module

AVCodecContext *	m_pAudioCtx = nullptr
	ffmpeg audio codec context

AVCodecID	m_codecId = AV_CODEC_ID_NONE
	current codec id

AVFrame *	m_pFrame
	decoded ffmpeg audio frame

int64_t	m_lastPts = AV_NOPTS_VALUE
	last seen PTS

int	m_passthroughMask
	passthrough mask to be set

int	m_currentPassthroughMask
	current passthrough mask

int	m_currentSampleRate
	current sample rate

int	m_currentNumChannels
	current number of channels

int	m_currentHwSampleRate
	current hw sample rate

int	m_currentHwNumChannels
	current number of hw channels

std::mutex	m_mutex
	decoder mutex

std::array< uint8_t, 32768 >	m_spdifIoBuffer
	spdif I/O buffer

AVFormatContext *	m_spdifFmtCtx = nullptr
	spdif muxer context

std::vector< uint8_t >	m_spdifOutputBuf
	spdif muxer output

Static Private Attributes
static constexpr int	AUDIO_PASSTHROUGH_NUM_CHANNELS = 2
	fixed passthrough channel number

static constexpr int	AUDIO_PASSTHROUGH_RATE_HZ = 48000
	fixed passthrough sample rate

Detailed Description

Audio Decoder.

FFmpeg Based Audio Decoder Frontend

Handles:

Audio packet decoding using FFmpeg
SPDIF passthrough
Format changes
Audio frame delivery to cSoftHdAudio

Definition at line 59 of file codec_audio.h.

Constructor & Destructor Documentation

◆ cAudioDecoder()

cAudioDecoder::cAudioDecoder ( cSoftHdAudio * audio )

Create a new audio decoder for the given audio context.

Parameters

audio audio context

Definition at line 60 of file codec_audio.cpp.

References GetPassthroughMaskString(), L_CODEC, LOGDEBUG2, LOGFATAL, m_passthroughMask, and m_pFrame.

◆ ~cAudioDecoder()

cAudioDecoder::~cAudioDecoder ( void )

Definition at line 70 of file codec_audio.cpp.

References Close(), and m_pFrame.

Member Function Documentation

◆ BuildIEC61937()

const std::vector< uint8_t > & cAudioDecoder::BuildIEC61937 ( const AVPacket * avpkt )

private

Prepend an IEC61937 header to the raw audio data by sending the avpkt to the spdif muxer.

Parameters

avpkt input packet

Returns: output data from the spdif muxer (maybe nullptr, if no output is available)

Definition at line 242 of file codec_audio.cpp.

References av_err2str, LOGERROR, m_spdifFmtCtx, and m_spdifOutputBuf.

Referenced by Passthrough().

◆ CheckUpdateFormat()

int cAudioDecoder::CheckUpdateFormat ( bool passthrough )

private

Handle audio format changes and setup audio, if format changed.

Return values

0	if new audio was correctly set up, otherwise return value of cSoftHdAudio::Setup()

Definition at line 296 of file codec_audio.cpp.

References AUDIO_PASSTHROUGH_NUM_CHANNELS, AUDIO_PASSTHROUGH_RATE_HZ, CloseSpdifMuxer(), GetPassthroughMaskString(), L_SOUND, LOGDEBUG2, LOGERROR, m_currentHwNumChannels, m_currentHwSampleRate, m_currentNumChannels, m_currentPassthroughMask, m_currentSampleRate, m_passthroughMask, m_pAudio, m_pAudioCtx, and cSoftHdAudio::Setup().

Referenced by DecodePCM(), and Passthrough().

◆ Close()

void cAudioDecoder::Close ( void )

Close the audio decoder.

Definition at line 134 of file codec_audio.cpp.

References AV_NOPTS_VALUE, CloseSpdifMuxer(), L_CODEC, LOGDEBUG2, m_codecId, m_lastPts, m_mutex, and m_pAudioCtx.

Referenced by cSoftHdDevice::PlayAudio(), and ~cAudioDecoder().

◆ CloseSpdifMuxer()

void cAudioDecoder::CloseSpdifMuxer ( void )

private

Close the spdif muxer and free the resources.

Definition at line 220 of file codec_audio.cpp.

References L_CODEC, LOGDEBUG2, m_spdifFmtCtx, and m_spdifOutputBuf.

Referenced by CheckUpdateFormat(), Close(), and OpenSpdifMuxer().

◆ Decode()

void cAudioDecoder::Decode ( const AVPacket * avpkt )

Forward an audio packet either to the decoder or passthrough.

Parameters

avpkt audio packet to decode

Definition at line 349 of file codec_audio.cpp.

References DecodePCM(), m_mutex, Passthrough(), and ShouldTryPassthrough().

Referenced by cSoftHdDevice::PlayAudio(), and cSoftHdDevice::PlayAudioPkts().

◆ DecodePCM()

void cAudioDecoder::DecodePCM ( const AVPacket * avpkt )

private

Decode an audio packet.

Parameters

avpkt audio packet to decode

Definition at line 398 of file codec_audio.cpp.

References av_err2str, AV_NOPTS_VALUE, CheckUpdateFormat(), cSoftHdAudio::Filter(), LOGERROR, m_lastPts, m_pAudio, m_pAudioCtx, and m_pFrame.

Referenced by Decode().

◆ FlushBuffers()

void cAudioDecoder::FlushBuffers ( void )

Flush the audio decoder buffers.

Also resets the last PTS and Codec ID

Definition at line 452 of file codec_audio.cpp.

References AV_NOPTS_VALUE, L_CODEC, LOGDEBUG2, m_codecId, m_lastPts, m_mutex, and m_pAudioCtx.

Referenced by cSoftHdDevice::FlushAudio().

◆ GetCodecId()

AVCodecID cAudioDecoder::GetCodecId ( ) const

inline

Definition at line 68 of file codec_audio.h.

References m_codecId.

Referenced by cSoftHdDevice::PlayAudio().

◆ Open()

void cAudioDecoder::Open	(	AVCodecID	codecId,
		AVCodecParameters *	par = `nullptr`,
		AVRational	timebase = `{ .num = 1, .den = 90000 }`
	)

Open and initiate the audio decoder.

Parameters

codecId	audio codec id
par	audio codec parameters
timebase	timebase

Todo:: FIXME: errors shouldn't be fatal, maybe just disable audio

Definition at line 86 of file codec_audio.cpp.

References GetPassthroughMaskString(), L_CODEC, LOGDEBUG2, LOGERROR, LOGFATAL, m_codecId, m_currentHwNumChannels, m_currentHwSampleRate, m_currentNumChannels, m_currentPassthroughMask, m_currentSampleRate, m_mutex, m_passthroughMask, and m_pAudioCtx.

Referenced by cSoftHdDevice::PlayAudio(), and cSoftHdDevice::SetAudioCodec().

◆ OpenSpdifMuxer()

bool cAudioDecoder::OpenSpdifMuxer	(	AVCodecID	codecId,
		int	sampleRate
	)

private

Open the spdif muxer.

Parameters

codecId	Codec ID of the stream
sampleRate	Samplerate of the stream

Returns: true, if the spdif muxer could be opened false on any error

Definition at line 178 of file codec_audio.cpp.

References CloseSpdifMuxer(), L_CODEC, LOGDEBUG2, LOGERROR, m_spdifFmtCtx, m_spdifIoBuffer, m_spdifOutputBuf, and SpdifWriteCallback().

Referenced by Passthrough().

◆ Passthrough()

int cAudioDecoder::Passthrough ( const AVPacket * avpkt )

private

Passthrough audio data.

Build spdif headers depending on the codec and send the data to the audio device.

Parameters

avpkt undecoded audio packet

Return values

0	codec is not supported for passthrough, sth. went wrong or we need more data to finish a spdif burst packet
1	spdif burst was enqueued

Definition at line 370 of file codec_audio.cpp.

References BuildIEC61937(), CheckUpdateFormat(), cSoftHdAudio::EnqueueSpdif(), LOGERROR, m_currentHwSampleRate, m_pAudio, m_pAudioCtx, m_spdifFmtCtx, OpenSpdifMuxer(), and cSoftHdAudio::SetTimebase().

Referenced by Decode().

◆ SetPassthroughMask()

void cAudioDecoder::SetPassthroughMask ( int mask )

Set audio pass-through mask.

Parameters

mask	codec mask to enable (AC-3, E-AC-3, DTS)

Definition at line 469 of file codec_audio.cpp.

References CODEC_AC3, CODEC_DTS, CODEC_EAC3, and m_passthroughMask.

Referenced by cSoftHdDevice::SetPassthroughMask().

◆ ShouldTryPassthrough()

bool cAudioDecoder::ShouldTryPassthrough ( void )

private

Test, if passthrough audio should be tried.

To enable passthrough, the current codec must be enabled in the setup

Currently supported: AC3, E-AC-3, DTS

Returns: true, if the data should be passed through

Definition at line 283 of file codec_audio.cpp.

References CODEC_AC3, CODEC_DTS, CODEC_EAC3, m_passthroughMask, and m_pAudioCtx.

Referenced by Decode().

◆ SpdifWriteCallback()

int cAudioDecoder::SpdifWriteCallback	(	void *	opaque,
		uint8_t *	buffer,
		int	bufferSize
	)

staticprivate

Callback for the spdif muxer.

This is called, whenever FFmpeg flushes data from the muxer to the AVIOContext. In the current implementation, a flush is forced after every muxer input write.

Definition at line 160 of file codec_audio.cpp.

Referenced by OpenSpdifMuxer().

Member Data Documentation

◆ AUDIO_PASSTHROUGH_NUM_CHANNELS

constexpr int cAudioDecoder::AUDIO_PASSTHROUGH_NUM_CHANNELS = 2

staticconstexprprivate

fixed passthrough channel number

Definition at line 88 of file codec_audio.h.

Referenced by CheckUpdateFormat().

◆ AUDIO_PASSTHROUGH_RATE_HZ

constexpr int cAudioDecoder::AUDIO_PASSTHROUGH_RATE_HZ = 48000

staticconstexprprivate

fixed passthrough sample rate

Definition at line 89 of file codec_audio.h.

Referenced by CheckUpdateFormat().

◆ m_codecId

AVCodecID cAudioDecoder::m_codecId = AV_CODEC_ID_NONE

private

current codec id

Definition at line 73 of file codec_audio.h.

Referenced by Close(), FlushBuffers(), GetCodecId(), and Open().

◆ m_currentHwNumChannels

int cAudioDecoder::m_currentHwNumChannels

private

current number of hw channels

Definition at line 81 of file codec_audio.h.

Referenced by CheckUpdateFormat(), and Open().

◆ m_currentHwSampleRate

int cAudioDecoder::m_currentHwSampleRate

private

current hw sample rate

Definition at line 80 of file codec_audio.h.

Referenced by CheckUpdateFormat(), Open(), and Passthrough().

◆ m_currentNumChannels

int cAudioDecoder::m_currentNumChannels

private

current number of channels

Definition at line 79 of file codec_audio.h.

Referenced by CheckUpdateFormat(), and Open().

◆ m_currentPassthroughMask

int cAudioDecoder::m_currentPassthroughMask

private

current passthrough mask

Definition at line 77 of file codec_audio.h.

Referenced by CheckUpdateFormat(), and Open().

◆ m_currentSampleRate

int cAudioDecoder::m_currentSampleRate

private

current sample rate

Definition at line 78 of file codec_audio.h.

Referenced by CheckUpdateFormat(), and Open().

◆ m_lastPts

int64_t cAudioDecoder::m_lastPts = AV_NOPTS_VALUE

private

last seen PTS

Definition at line 75 of file codec_audio.h.

Referenced by Close(), DecodePCM(), and FlushBuffers().

◆ m_mutex

std::mutex cAudioDecoder::m_mutex

private

decoder mutex

Definition at line 82 of file codec_audio.h.

Referenced by Close(), Decode(), FlushBuffers(), and Open().

◆ m_passthroughMask

int cAudioDecoder::m_passthroughMask

private

passthrough mask to be set

Definition at line 76 of file codec_audio.h.

Referenced by cAudioDecoder(), CheckUpdateFormat(), Open(), SetPassthroughMask(), and ShouldTryPassthrough().

◆ m_pAudio

cSoftHdAudio* cAudioDecoder::m_pAudio

private

audio module

Definition at line 71 of file codec_audio.h.

Referenced by CheckUpdateFormat(), DecodePCM(), and Passthrough().

◆ m_pAudioCtx

AVCodecContext* cAudioDecoder::m_pAudioCtx = nullptr

private

ffmpeg audio codec context

Definition at line 72 of file codec_audio.h.

Referenced by CheckUpdateFormat(), Close(), DecodePCM(), FlushBuffers(), Open(), Passthrough(), and ShouldTryPassthrough().

◆ m_pFrame

AVFrame* cAudioDecoder::m_pFrame

private

decoded ffmpeg audio frame

Definition at line 74 of file codec_audio.h.

Referenced by cAudioDecoder(), DecodePCM(), and ~cAudioDecoder().

◆ m_spdifFmtCtx

AVFormatContext* cAudioDecoder::m_spdifFmtCtx = nullptr

private

spdif muxer context

Definition at line 85 of file codec_audio.h.

Referenced by BuildIEC61937(), CloseSpdifMuxer(), OpenSpdifMuxer(), and Passthrough().

◆ m_spdifIoBuffer

std::array<uint8_t, 32768> cAudioDecoder::m_spdifIoBuffer

private

spdif I/O buffer

Definition at line 84 of file codec_audio.h.

Referenced by OpenSpdifMuxer().

◆ m_spdifOutputBuf

std::vector<uint8_t> cAudioDecoder::m_spdifOutputBuf

private

spdif muxer output

Definition at line 86 of file codec_audio.h.

Referenced by BuildIEC61937(), CloseSpdifMuxer(), and OpenSpdifMuxer().

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

Public Member Functions

Private Member Functions

Static Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ cAudioDecoder()

◆ ~cAudioDecoder()

Member Function Documentation

◆ BuildIEC61937()

◆ CheckUpdateFormat()

◆ Close()

◆ CloseSpdifMuxer()

◆ Decode()

◆ DecodePCM()

◆ FlushBuffers()

◆ GetCodecId()

◆ Open()

◆ OpenSpdifMuxer()

◆ Passthrough()

◆ SetPassthroughMask()

◆ ShouldTryPassthrough()

◆ SpdifWriteCallback()

Member Data Documentation

◆ AUDIO_PASSTHROUGH_NUM_CHANNELS

◆ AUDIO_PASSTHROUGH_RATE_HZ

◆ m_codecId

◆ m_currentHwNumChannels

◆ m_currentHwSampleRate

◆ m_currentNumChannels

◆ m_currentPassthroughMask

◆ m_currentSampleRate

◆ m_lastPts

◆ m_mutex

◆ m_passthroughMask

◆ m_pAudio

◆ m_pAudioCtx

◆ m_pFrame

◆ m_spdifFmtCtx

◆ m_spdifIoBuffer

◆ m_spdifOutputBuf