This file defines functions, structures and macros for audio output object. More...

Include dependency graph for vlc_aout.h:

Data Structures
struct	audio_output
	Audio output object. More...
struct	aout_fifo_t
	Audio output buffer FIFO. More...
struct	aout_packet_t
Defines
#define	AOUT_MAX_FILTERS 10
#define	AOUT_MAX_ADVANCE_TIME (AOUT_MAX_PREPARE_TIME + CLOCK_FREQ)
#define	AOUT_MAX_PREPARE_TIME (2 * CLOCK_FREQ)
#define	AOUT_MIN_PREPARE_TIME AOUT_MAX_PTS_ADVANCE
#define	AOUT_MAX_PTS_ADVANCE (CLOCK_FREQ / 25)
	Maximum advance of actual audio playback time to coded PTS, above which downsampling will be performed.
#define	AOUT_MAX_PTS_DELAY (3 * CLOCK_FREQ / 50)
	Maximum delay of actual audio playback time from coded PTS, above which upsampling will be performed.
#define	AOUT_MAX_RESAMPLING 10
#define	AOUT_FMTS_IDENTICAL(p_first, p_second)
#define	AOUT_FMTS_SIMILAR(p_first, p_second)
#define	AOUT_FMT_LINEAR(p_format) (aout_BitsPerSample((p_format)->i_format) != 0)
#define	VLC_CODEC_SPDIFL VLC_FOURCC('s','p','d','i')
#define	VLC_CODEC_SPDIFB VLC_FOURCC('s','p','d','b')
#define	AOUT_FMT_SPDIF(p_format)
#define	FIXED32_FRACBITS 28
#define	FIXED32_MIN ((vlc_fixed_t) -0x80000000L)
#define	FIXED32_MAX ((vlc_fixed_t) +0x7fffffffL)
#define	FIXED32_ONE ((vlc_fixed_t) 0x10000000)
#define	AOUT_CHAN_CENTER 0x1
#define	AOUT_CHAN_LEFT 0x2
#define	AOUT_CHAN_RIGHT 0x4
#define	AOUT_CHAN_REARCENTER 0x10
#define	AOUT_CHAN_REARLEFT 0x20
#define	AOUT_CHAN_REARRIGHT 0x40
#define	AOUT_CHAN_MIDDLELEFT 0x100
#define	AOUT_CHAN_MIDDLERIGHT 0x200
#define	AOUT_CHAN_LFE 0x1000
#define	AOUT_CHAN_DOLBYSTEREO 0x10000
#define	AOUT_CHAN_DUALMONO 0x20000
#define	AOUT_CHAN_REVERSESTEREO 0x40000
#define	AOUT_CHAN_PHYSMASK 0xFFFF
#define	AOUT_CHAN_MAX 9
#define	AOUT_VAR_MONO 1
#define	AOUT_VAR_STEREO 2
#define	AOUT_VAR_2F2R 4
#define	AOUT_VAR_3F2R 5
#define	AOUT_VAR_5_1 6
#define	AOUT_VAR_6_1 7
#define	AOUT_VAR_7_1 8
#define	AOUT_VAR_SPDIF 10
#define	AOUT_VAR_CHAN_STEREO 1
#define	AOUT_VAR_CHAN_RSTEREO 2
#define	AOUT_VAR_CHAN_LEFT 3
#define	AOUT_VAR_CHAN_RIGHT 4
#define	AOUT_VAR_CHAN_DOLBYS 5
#define	aout_BufferFree(buffer) block_Release( buffer )
#define	AOUT_SPDIF_SIZE 6144
#define	A52_FRAME_NB 1536
#define	aout_FormatPrint(o, t, f) aout_FormatPrint(VLC_OBJECT(o), t, f)
Typedefs
typedef int32_t	vlc_fixed_t
typedef int(*	aout_volume_cb )(audio_output_t *, float, bool)
Functions
int	aout_CheckChannelReorder (const uint32_t pi_chan_order_in, const uint32_t pi_chan_order_out, uint32_t i_channel_mask, int i_channels, int *pi_chan_table)
	This function computes the reordering needed to go from pi_chan_order_in to pi_chan_order_out.
void	aout_ChannelReorder (uint8_t , int, int, const int , int)
bool	aout_CheckChannelExtraction (int pi_selection, uint32_t pi_layout, int pi_channels, const uint32_t pi_order_dst[9], const uint32_t pi_order_src, int i_channels)
	This fonction will compute the extraction parameter into pi_selection to go from i_channels with their type given by pi_order_src[] into the order describe by pi_order_dst.
void	aout_ChannelExtract (void p_dst, int i_dst_channels, const void p_src, int i_src_channels, int i_sample_count, const int *pi_selection, int i_bits_per_sample)
	Do the actual channels extraction using the parameters created by aout_CheckChannelExtraction.
static unsigned	aout_FormatNbChannels (const audio_sample_format_t *fmt)
unsigned int	aout_BitsPerSample (vlc_fourcc_t i_format)
void	aout_FormatPrepare (audio_sample_format_t *p_format)
void	aout_FormatPrint (vlc_object_t , const char , const audio_sample_format_t *)
	Prints an audio sample format in a human-readable form.
const char *	aout_FormatPrintChannels (const audio_sample_format_t *)
void	aout_VolumeNoneInit (audio_output_t *)
	Configures the dummy volume setter.
void	aout_VolumeSoftInit (audio_output_t *)
	Configures the volume setter for software mixing and apply the default volume.
void	aout_VolumeHardInit (audio_output_t *, aout_volume_cb)
	Configures a custom volume setter.
void	aout_VolumeHardSet (audio_output_t *, float, bool)
	Supply or update the current custom ("hardware") volume.
void	aout_TimeReport (audio_output_t *, mtime_t)
	Notifies the audio input of the drift from the requested audio playback timestamp (block_t::i_pts) to the anticipated playback time as reported by the audio output hardware.
int	aout_ChannelsRestart (vlc_object_t , const char , vlc_value_t, vlc_value_t, void *)
vout_thread_t *	aout_filter_RequestVout (filter_t , vout_thread_t p_vout, video_format_t *p_fmt)
void	aout_PacketInit (audio_output_t , aout_packet_t , unsigned)
void	aout_PacketDestroy (audio_output_t *)
void	aout_PacketPlay (audio_output_t , block_t )
void	aout_PacketPause (audio_output_t *, bool, mtime_t)
void	aout_PacketFlush (audio_output_t *, bool)
block_t *	aout_PacketNext (audio_output_t *, mtime_t)
	Dequeues the next audio packet (a.k.a.
Variables
static const uint32_t	pi_vlc_chan_order_wg4 []
	It describes the audio channel order VLC expect.

Detailed Description

This file defines functions, structures and macros for audio output object.

Define Documentation

#define A52_FRAME_NB 1536

#define aout_BufferFree ( buffer ) block_Release( buffer )

Referenced by aout_DecDeleteBuffer(), aout_DecPlay(), aout_FifoDestroy(), aout_FifoReset(), aout_OutputSlice(), DecoderFlushBuffering(), DecoderPlayAudio(), and inputDrop().

#define AOUT_CHAN_CENTER 0x1

Referenced by aout_CheckChannelExtraction(), aout_FormatPrintChannels(), and aout_OutputNew().

#define AOUT_CHAN_DOLBYSTEREO 0x10000

Referenced by aout_FormatPrintChannels(), and aout_OutputNew().

#define AOUT_CHAN_DUALMONO 0x20000

Referenced by aout_FormatPrintChannels(), and aout_OutputNew().

#define AOUT_CHAN_LEFT 0x2

Referenced by aout_FormatPrintChannels(), aout_new_buffer(), and aout_OutputNew().

#define AOUT_CHAN_LFE 0x1000

Referenced by aout_FormatPrintChannels().

#define AOUT_CHAN_MAX 9

Referenced by aout_ChannelReorder(), and aout_CheckChannelReorder().

#define AOUT_CHAN_MIDDLELEFT 0x100

Referenced by aout_FormatPrintChannels().

#define AOUT_CHAN_MIDDLERIGHT 0x200

Referenced by aout_FormatPrintChannels().

#define AOUT_CHAN_PHYSMASK 0xFFFF

Referenced by aout_FormatNbChannels(), aout_FormatPrintChannels(), aout_new_buffer(), aout_OutputNew(), and EsOutUpdateInfo().

#define AOUT_CHAN_REARCENTER 0x10

Referenced by aout_FormatPrintChannels().

#define AOUT_CHAN_REARLEFT 0x20

Referenced by aout_FormatPrintChannels().

#define AOUT_CHAN_REARRIGHT 0x40

Referenced by aout_FormatPrintChannels().

#define AOUT_CHAN_REVERSESTEREO 0x40000

Referenced by aout_FormatPrintChannels().

#define AOUT_CHAN_RIGHT 0x4

Referenced by aout_CheckChannelExtraction(), aout_FormatPrintChannels(), aout_new_buffer(), and aout_OutputNew().

#define AOUT_FMT_LINEAR ( p_format ) (aout_BitsPerSample((p_format)->i_format) != 0)

Referenced by aout_InputNew(), aout_OutputNew(), aout_OutputSlice(), aout_PacketNext(), and SplitConversion().

#define AOUT_FMT_SPDIF ( p_format )

Value:

( ((p_format)->i_format == VLC_CODEC_SPDIFL)       \
       || ((p_format)->i_format == VLC_CODEC_SPDIFB)   \
       || ((p_format)->i_format == VLC_CODEC_A52)       \
       || ((p_format)->i_format == VLC_CODEC_DTS) )

#define AOUT_FMTS_IDENTICAL	(	p_first,
		p_second
	)

Value:

(                          \
    ((p_first)->i_format == (p_second)->i_format)                           \
      && AOUT_FMTS_SIMILAR(p_first, p_second) )

Referenced by aout_DecNew(), aout_FiltersCreatePipeline(), aout_InputNew(), and SplitConversion().

#define AOUT_FMTS_SIMILAR	(	p_first,
		p_second
	)

Value:

(                            \
    ((p_first)->i_rate == (p_second)->i_rate)                               \
      && ((p_first)->i_physical_channels == (p_second)->i_physical_channels)\
      && ((p_first)->i_original_channels == (p_second)->i_original_channels) )

#define aout_FormatPrint	(	o,
		t,
		f
	)		aout_FormatPrint(VLC_OBJECT(o), t, f)

Referenced by aout_InputNew(), and aout_OutputNew().

#define AOUT_MAX_ADVANCE_TIME (AOUT_MAX_PREPARE_TIME + CLOCK_FREQ)

Referenced by DecoderPlayAudio().

#define AOUT_MAX_FILTERS 10

Referenced by aout_InputNew().

#define AOUT_MAX_PREPARE_TIME (2 * CLOCK_FREQ)

Referenced by DecoderPlayAudio().

#define AOUT_MAX_PTS_ADVANCE (CLOCK_FREQ / 25)

Maximum advance of actual audio playback time to coded PTS, above which downsampling will be performed.

Referenced by aout_InputPlay(), aout_PacketNext(), and aout_TimeReport().

#define AOUT_MAX_PTS_DELAY (3 * CLOCK_FREQ / 50)

Maximum delay of actual audio playback time from coded PTS, above which upsampling will be performed.

Referenced by aout_InputPlay(), aout_PacketNext(), and aout_TimeReport().

#define AOUT_MAX_RESAMPLING 10

#define AOUT_MIN_PREPARE_TIME AOUT_MAX_PTS_ADVANCE

Referenced by aout_InputPlay().

#define AOUT_SPDIF_SIZE 6144

#define AOUT_VAR_2F2R 4

#define AOUT_VAR_3F2R 5

#define AOUT_VAR_5_1 6

#define AOUT_VAR_6_1 7

#define AOUT_VAR_7_1 8

#define AOUT_VAR_CHAN_DOLBYS 5

Referenced by aout_OutputNew().

#define AOUT_VAR_CHAN_LEFT 3

Referenced by aout_OutputNew().

#define AOUT_VAR_CHAN_RIGHT 4

Referenced by aout_OutputNew().

#define AOUT_VAR_CHAN_RSTEREO 2

Referenced by aout_OutputNew().

#define AOUT_VAR_CHAN_STEREO 1

Referenced by aout_OutputNew().

#define AOUT_VAR_MONO 1

#define AOUT_VAR_SPDIF 10

#define AOUT_VAR_STEREO 2

#define FIXED32_FRACBITS 28

#define FIXED32_MAX ((vlc_fixed_t) +0x7fffffffL)

#define FIXED32_MIN ((vlc_fixed_t) -0x80000000L)

#define FIXED32_ONE ((vlc_fixed_t) 0x10000000)

#define VLC_CODEC_SPDIFB VLC_FOURCC('s','p','d','b')

#define VLC_CODEC_SPDIFL VLC_FOURCC('s','p','d','i')

Typedef Documentation

typedef int(* aout_volume_cb)(audio_output_t *, float, bool)

typedef int32_t vlc_fixed_t

Function Documentation

unsigned int aout_BitsPerSample ( vlc_fourcc_t i_format )

void aout_ChannelExtract	(	void *	p_dst,
		int	i_dst_channels,
		const void *	p_src,
		int	i_src_channels,
		int	i_sample_count,
		const int *	pi_selection,
		int	i_bits_per_sample
	)

Do the actual channels extraction using the parameters created by aout_CheckChannelExtraction.

XXX this function does not work in place (p_dst and p_src must not overlap). XXX Only 8, 16, 24, 32, 64 bits per sample are supported.

References ExtractChannel().

void aout_ChannelReorder	(	uint8_t *	,
		int	,
		int	,
		const int *	,
		int
	)

References AOUT_CHAN_MAX.

int aout_ChannelsRestart	(	vlc_object_t *	,
		const char *	,
		vlc_value_t	,
		vlc_value_t	,
		void *
	)

References aout_RequestRestart(), and var_Destroy.

Referenced by aout_OutputNew().

bool aout_CheckChannelExtraction	(	int *	pi_selection,
		uint32_t *	pi_layout,
		int *	pi_channels,
		const uint32_t	pi_order_dst[9],
		const uint32_t *	pi_order_src,
		int	i_channels
	)

This fonction will compute the extraction parameter into pi_selection to go from i_channels with their type given by pi_order_src[] into the order describe by pi_order_dst.

It will also set :

*pi_channels as the number of channels that will be extracted which is lower (in case of non understood channels type) or equal to i_channels.
the layout of the channels (*pi_layout).

It will return true if channel extraction is really needed, in which case aout_ChannelExtract must be used

XXX It must be used when the source may have channel type not understood by VLC. In this case the channel type pi_order_src[] must be set to 0. XXX It must also be used if multiple channels have the same type.

References AOUT_CHAN_CENTER, AOUT_CHAN_RIGHT, and pi_vlc_chan_order_wg4.

int aout_CheckChannelReorder	(	const uint32_t *	pi_chan_order_in,
		const uint32_t *	pi_chan_order_out,
		uint32_t	i_channel_mask,
		int	i_channels,
		int *	pi_chan_table
	)

This function computes the reordering needed to go from pi_chan_order_in to pi_chan_order_out.

If pi_chan_order_in or pi_chan_order_out is NULL, it will assume that vlc internal (WG4) order is requested.

References AOUT_CHAN_MAX, and pi_vlc_chan_order_wg4.

vout_thread_t* aout_filter_RequestVout	(	filter_t *	,
		vout_thread_t *	p_vout,
		video_format_t *	p_fmt
	)

References aout_input_t::b_recycle_vout, filter_owner_sys_t::p_input, filter_t::p_owner, aout_request_vout_t::p_private, aout_request_vout_t::pf_request_vout, and aout_input_t::request_vout.

static unsigned aout_FormatNbChannels ( const audio_sample_format_t * fmt ) [inline, static]

References AOUT_CHAN_PHYSMASK, audio_format_t::i_physical_channels, and popcount().

Referenced by aout_DecNew(), and aout_FormatPrepare().

void aout_FormatPrepare ( audio_sample_format_t * p_format )

References aout_BitsPerSample(), aout_FormatNbChannels(), audio_format_t::i_bitspersample, audio_format_t::i_bytes_per_frame, audio_format_t::i_channels, audio_format_t::i_format, and audio_format_t::i_frame_length.

Referenced by aout_InputNew(), aout_new_buffer(), aout_OutputNew(), and SplitConversion().

void aout_FormatPrint	(	vlc_object_t *	,
		const char *	,
		const audio_sample_format_t *
	)

Prints an audio sample format in a human-readable form.

References aout_FormatPrintChannels(), audio_format_t::i_bytes_per_frame, audio_format_t::i_format, audio_format_t::i_frame_length, audio_format_t::i_rate, and msg_Dbg.

const char* aout_FormatPrintChannels ( const audio_sample_format_t * )

References AOUT_CHAN_CENTER, AOUT_CHAN_DOLBYSTEREO, AOUT_CHAN_DUALMONO, AOUT_CHAN_LEFT, AOUT_CHAN_LFE, AOUT_CHAN_MIDDLELEFT, AOUT_CHAN_MIDDLERIGHT, AOUT_CHAN_PHYSMASK, AOUT_CHAN_REARCENTER, AOUT_CHAN_REARLEFT, AOUT_CHAN_REARRIGHT, AOUT_CHAN_REVERSESTEREO, AOUT_CHAN_RIGHT, audio_format_t::i_original_channels, and audio_format_t::i_physical_channels.

Referenced by aout_FormatPrint(), aout_FormatsPrint(), and EsOutUpdateInfo().

void aout_PacketDestroy ( audio_output_t * )

References aout_FifoDestroy(), aout_packet(), aout_packet_t::fifo, aout_packet_t::lock, aout_packet_t::partial, and vlc_mutex_destroy().

void aout_PacketFlush	(	audio_output_t *	,
		bool
	)

References aout_FifoReset(), aout_packet(), aout_packet_t::fifo, aout_packet_t::lock, aout_packet_t::partial, vlc_mutex_lock(), and vlc_mutex_unlock().

void aout_PacketInit	(	audio_output_t *	,
		aout_packet_t *	,
		unsigned
	)

References aout_FifoInit, aout_packet(), aout_packet_t::fifo, audio_output::format, audio_format_t::i_rate, aout_packet_t::lock, aout_packet_t::partial, aout_packet_t::pause_date, aout_packet_t::samples, aout_packet_t::starving, aout_packet_t::time_report, and vlc_mutex_init().

block_t* aout_PacketNext	(	audio_output_t *	p_aout,
		mtime_t	start_date
	)

Dequeues the next audio packet (a.k.a.

audio fragment). The audio output plugin must first call aout_PacketPlay() to queue the decoded audio samples. Typically, audio_output_t.pf_play is set to, or calls aout_PacketPlay().

Note:: This function is considered legacy. Please do not use this function in new audio output plugins.

Parameters:

	p_aout	audio output instance
	start_date	expected PTS of the audio packet

References aout_FifoMoveDates(), aout_FifoPop(), AOUT_FMT_LINEAR, AOUT_MAX_PTS_ADVANCE, AOUT_MAX_PTS_DELAY, aout_packet(), block_Release(), aout_packet_t::fifo, audio_output::format, block_t::i_length, block_t::i_pts, aout_packet_t::lock, mdate(), msg_Dbg, msg_Warn, aout_fifo_t::p_first, aout_packet_t::partial, aout_packet_t::pause_date, aout_packet_t::starving, aout_packet_t::time_report, vlc_mutex_lock(), vlc_mutex_unlock(), and VLC_TS_INVALID.

void aout_PacketPause	(	audio_output_t *	,
		bool	,
		mtime_t
	)

References aout_FifoMoveDates(), aout_packet(), aout_packet_t::fifo, aout_packet_t::lock, aout_packet_t::partial, aout_packet_t::pause_date, vlc_mutex_lock(), vlc_mutex_unlock(), and VLC_TS_INVALID.

void aout_PacketPlay	(	audio_output_t *	,
		block_t *
	)

References aout_FifoPush(), aout_OutputSlice(), aout_packet(), aout_TimeReport(), aout_packet_t::fifo, aout_packet_t::lock, mdate(), aout_packet_t::partial, aout_packet_t::time_report, vlc_mutex_lock(), vlc_mutex_unlock(), and VLC_TS_INVALID.

void aout_TimeReport	(	audio_output_t *	aout,
		mtime_t	ideal
	)

Notifies the audio input of the drift from the requested audio playback timestamp (block_t::i_pts) to the anticipated playback time as reported by the audio output hardware.

Depending on the drift amplitude, the input core may ignore the drift trigger upsampling or downsampling, or even discard samples. Future VLC versions may instead adjust the input decoding speed.

The audio output plugin is responsible for estimating the ideal current playback time defined as follows: ideal time = buffer timestamp - (output latency + pending buffer duration)

Practically, this is the PTS (block_t.i_pts) of the current buffer minus the latency reported by the output programming interface. Computing the estimated drift directly would probably be more intuitive. However the use of an absolute time value does not introduce extra measurement errors due to the CPU scheduling jitter and clock resolution. Furthermore, the ideal while it is an abstract value, is easy for most audio output plugins to compute. The following definition is equivalent but depends on the clock time: ideal time = real time + drift

Note:: If aout_LatencyReport() is never called, the core will assume that there is no drift.

Parameters:

ideal

estimated ideal time as defined above.

References aout_assert_locked, AOUT_MAX_PTS_ADVANCE, AOUT_MAX_PTS_DELAY, aout_owner(), aout_owner_t::date, date_Get(), date_Move(), mdate(), msg_Warn, aout_owner_t::sync, and VLC_TS_INVALID.

Referenced by aout_PacketPlay().

void aout_VolumeHardInit	(	audio_output_t *	aout,
		aout_volume_cb	setter
	)

Configures a custom volume setter.

This is used by audio outputs that can control the hardware volume directly and/or emulate it internally.

Parameters:

setter

volume setter callback

References aout_assert_locked, audio_output::pf_volume_set, var_Create, VLC_VAR_BOOL, VLC_VAR_DOINHERIT, and VLC_VAR_INTEGER.

void aout_VolumeHardSet	(	audio_output_t *	aout,
		float	volume,
		bool	mute
	)

Supply or update the current custom ("hardware") volume.

Note:: This only makes sense after calling aout_VolumeHardInit().

Parameters:

	setter	volume setter callback
	volume	current custom volume
	mute	current mute flag

Warning:: The caller (i.e. the audio output plug-in) is responsible for interlocking and synchronizing call to this function and to the audio_output_t.pf_volume_set callback. This ensures that VLC gets correct volume information (possibly with a latency).

References AOUT_VOLUME_DEFAULT, var_SetBool, var_SetInteger, and var_TriggerCallback.

void aout_VolumeNoneInit ( audio_output_t * aout )

Configures the dummy volume setter.

Note:: Audio output plugins for which volume is irrelevant should call this function during activation.

References audio_output::pf_volume_set, and var_Destroy.

Referenced by aout_New(), and aout_OutputDelete().

void aout_VolumeSoftInit ( audio_output_t * aout )

Configures the volume setter for software mixing and apply the default volume.

Note:: Audio output plugins that cannot apply the volume should call this function during activation.

References aout_assert_locked, AOUT_VOLUME_DEFAULT, aout_VolumeSoftSet(), audio_output::pf_volume_set, var_InheritBool, and var_InheritInteger.

Variable Documentation

const uint32_t pi_vlc_chan_order_wg4[] [static]

Initial value:

{
     0x2 ,  0x4 ,
     0x100 ,  0x200 ,
     0x20 ,  0x40 ,  0x10 ,
     0x1 ,  0x1000 , 0
}

It describes the audio channel order VLC expect.

Referenced by aout_CheckChannelExtraction(), and aout_CheckChannelReorder().

vlc_aout.h File Reference

Data Structures

Defines

Typedefs

Functions

Variables

Detailed Description

Define Documentation

Typedef Documentation

Function Documentation

Variable Documentation