AudioStreamInfo describes an elementary audio stream. More...

#include <av.h>

Inheritance diagram for AudioStreamInfo:

Public Member Functions
virtual int32_t	bitsPerSample () const =0
	Returns the number of bits per sample (sample resolution).

virtual int32_t	bytesPerFrame () const =0
	Returns the number of bytes occupied by an audio frame (smallest discrete unit).

virtual int32_t	channelLayout () const =0
	Returns the channel layout which defines the mapping between channels and speakers.

virtual int32_t	channels () const =0
	Returns the number of audio channels.

virtual AudioStreamInfo *	clone () const =0
	Creates a copy of this object.

virtual bool_t	copyTo (AudioStreamInfo *destination) const =0
	Copies the state of the current object to a destination object of the same type.

virtual int32_t	pcmFlags () const =0
	Returns the audio format flags which describe various properties of the audio stream.

virtual int32_t	sampleRate () const =0
	Returns the audio sample rate.

virtual bool_t	setBitsPerSample (int32_t bitsPerSample)=0
	Sets the number of bits per sample (sample resolution).

virtual bool_t	setBytesPerFrame (int32_t bytesPerFrame)=0
	Sets the number of bytes occupied by an audio frame (smallest discrete unit).

virtual bool_t	setChannelLayout (int32_t channelLayout)=0
	Sets the channel layout which defines the mapping between channels and speakers.

virtual bool_t	setChannels (int32_t numChannels)=0
	Sets the number of audio channels.

virtual bool_t	setPcmFlags (int32_t flags)=0
	Sets the audio format flags which describe various properties of the audio stream.

virtual bool_t	setSampleRate (int32_t sampleRate)=0
	Sets the audio sample rate.

Public Member Functions inherited from StreamInfo
virtual int32_t	bitrate () const =0
	Returns the stream bitrate.

virtual int32_t	bitrateMode () const =0
	Returns the stream bitrate mode.

virtual StreamInfo *	clone () const =0
	Creates a copy of this object.

virtual bool_t	copyTo (StreamInfo *destination) const =0
	Copies the state of the current object to a destination object of the same type.

virtual double	duration () const =0
	Returns the stream duration.

virtual int32_t	ID () const =0
	Returns the ID of the elementary stream.

virtual bool_t	immutable () const =0
	Returns whether the object is immutable.

virtual MediaType::Enum	mediaType () const =0
	Returns the stream media type.

virtual int32_t	programNumber () const =0
	Returns the number of the program to which the elementary stream belongs.

virtual bool_t	reset ()=0
	Resets the stream information to its default state.

virtual bool_t	setBitrate (int32_t bitrate)=0
	Sets the stream bitrate.

virtual bool_t	setBitrateMode (int32_t bitrateMode)=0
	Sets the stream bitrate mode.

virtual bool_t	setDuration (double duration)=0
	Sets the stream duration in seconds.

virtual bool_t	setID (int32_t id)=0
	Sets the ID of the elementary stream.

virtual bool_t	setProgramNumber (int32_t programNumber)=0
	Sets the program to which the elementary stream belongs.

virtual bool_t	setStreamSubType (StreamSubType::Enum type)=0
	Sets the stream subtype.

virtual bool_t	setStreamType (StreamType::Enum type)=0
	Sets the stream type.

virtual StreamSubType::Enum	streamSubType () const =0
	Returns the stream subtype.

virtual StreamType::Enum	streamType () const =0
	Returns the stream type.

Public Member Functions inherited from Reference
virtual int32_t	release () const =0
	Releases the instance.

virtual int32_t	retain () const =0
	Retains the instance.

virtual int32_t	retainCount () const =0
	Returns the current reference count.

Protected Member Functions
	~AudioStreamInfo ()
	This object can be destroyed only by its implementation.

Protected Member Functions inherited from StreamInfo
	~StreamInfo ()
	This object can be destroyed only by its implementation.

Detailed Description

AudioStreamInfo describes an elementary audio stream.

Constructor & Destructor Documentation

◆ ~AudioStreamInfo()

~AudioStreamInfo ( )

protected

This object can be destroyed only by its implementation.

The caller must use Reference::release.

See also: Object Management

Member Function Documentation

◆ bitsPerSample()

virtual int32_t bitsPerSample ( ) const

pure virtual

Returns the number of bits per sample (sample resolution).

Returns: bits per sample (usually 8, 16, 24 or 32).

Normally bits per sample is not defined for a compressed audio stream and is 0. However it is possible for a compressed audio stream to return a positive value as an indication of audio quality. It can also designate the bits per sample of the LPCM stream once the compressed stream is decoded.

◆ bytesPerFrame()

virtual int32_t bytesPerFrame ( ) const

pure virtual

Returns the number of bytes occupied by an audio frame (smallest discrete unit).

Returns: bytes per frame.

A frame is the smallest unit in an audio stream. It may contain one or more samples. Depending on the audio stream type the frame may contain fixed or variable number of samples.

For compressed streams the frame size is variable even if there are fixed number of samples in each frame. In this case bytes per frame is 0.

For an LCPM stream the frame size is constant. In this case bytes per frame is a positive value. Normally for interleaved LPCM streams the following is true:

bytesPerFrame() / channels() == (sample size in bytes)
The valid bits in a sample are given by bitsPerSample() and they are aligned towards the hi-order byte.

Returns: TRUE if bytes per sample is successfully set, otherwise FALSE.

◆ channelLayout()

virtual int32_t channelLayout ( ) const

pure virtual

Returns the channel layout which defines the mapping between channels and speakers.

Returns: A combination of flags defined in the AudioChannelFlags::Enum.

◆ channels()

virtual int32_t channels ( ) const

pure virtual

Returns the number of audio channels.

Returns: Number of channels.

◆ clone()

virtual AudioStreamInfo * clone ( ) const

pure virtual

Creates a copy of this object.

Returns: A new AudioStreamInfo. The caller is responsible for releasing the new object when it is not needed anymore.

See also: Object Management

Implements StreamInfo.

◆ copyTo()

virtual bool_t copyTo ( AudioStreamInfo * destination ) const

pure virtual

Copies the state of the current object to a destination object of the same type.

The reference count of the source and the destination is not modified.

Parameters

destination [out] A pointer to the destination object

Returns: TRUE if the object state is copied, FALSE otherwise.

◆ pcmFlags()

virtual int32_t pcmFlags ( ) const

pure virtual

Returns the audio format flags which describe various properties of the audio stream.

Returns: A combination of flags defined in PcmFlags::Enum.

◆ sampleRate()

virtual int32_t sampleRate ( ) const

pure virtual

Returns the audio sample rate.

Returns: sample rate (Hz)

◆ setBitsPerSample()

virtual bool_t setBitsPerSample ( int32_t bitsPerSample )

pure virtual

Sets the number of bits per sample (sample resolution).

Parameters

bitsPerSample (usually 8, 16, 24 or 32)

Returns: TRUE if the number of bits per sample is successfully set, otherwise FALSE.

◆ setBytesPerFrame()

virtual bool_t setBytesPerFrame ( int32_t bytesPerFrame )

pure virtual

Sets the number of bytes occupied by an audio frame (smallest discrete unit).

Parameters

bytesPerFrame [in] Specifies how many bytes are occupied by each audio frame. Normally it is valid (greater than 0) for LPCM streams and invalid (0) for compressed audio streams.

Returns: TRUE if the number of bytes per frame is successfully set, otherwise FALSE.

◆ setChannelLayout()

virtual bool_t setChannelLayout ( int32_t channelLayout )

pure virtual

Sets the channel layout which defines the mapping between channels and speakers.

Parameters

channelLayout A combination of flags defined in the AudioChannelFlags::Enum.

Returns: TRUE if the channel layout is successfully set, otherwise FALSE.

◆ setChannels()

virtual bool_t setChannels ( int32_t numChannels )

pure virtual

Sets the number of audio channels.

Parameters

numChannels number of channels.

Returns: TRUE if the number of channels is successfully set, otherwise FALSE.

◆ setPcmFlags()

virtual bool_t setPcmFlags ( int32_t flags )

pure virtual

Sets the audio format flags which describe various properties of the audio stream.

Parameters

flags A combination of flags defined in PcmFlags::Enum.

Returns: TRUE if the flags are successfully set, otherwise FALSE.

◆ setSampleRate()

virtual bool_t setSampleRate ( int32_t sampleRate )

pure virtual

Sets the audio sample rate.

Parameters

sampleRate sample rate (Hz)

Returns: TRUE if the sample rate is successfully set, otherwise FALSE.

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ~AudioStreamInfo()

Member Function Documentation

◆ bitsPerSample()

◆ bytesPerFrame()

◆ channelLayout()

◆ channels()

◆ clone()

◆ copyTo()

◆ pcmFlags()

◆ sampleRate()

◆ setBitsPerSample()

◆ setBytesPerFrame()

◆ setChannelLayout()

◆ setChannels()

◆ setPcmFlags()

◆ setSampleRate()