visualisation_stream

#include <vis.h>

Inheritance diagram for visualisation_stream:

Public Member Functions
	FB2K_MAKE_SERVICE_INTERFACE (visualisation_stream, service_base)
virtual bool	get_absolute_time (double &p_value)=0
virtual bool	get_chunk_absolute (audio_chunk &p_chunk, double p_offset, double p_requested_length)=0
virtual bool	get_spectrum_absolute (audio_chunk &p_chunk, double p_offset, unsigned p_fft_size)=0
virtual void	make_fake_chunk_absolute (audio_chunk &p_chunk, double p_offset, double p_requested_length)=0
virtual void	make_fake_spectrum_absolute (audio_chunk &p_chunk, double p_offset, unsigned p_fft_size)=0
Public Member Functions inherited from service_base
template<typename outPtr_t >
bool	cast (outPtr_t &outPtr)
virtual int	service_add_ref ()=0 throw ()
virtual bool	service_query (service_ptr_t< service_base > &p_out, const GUID &p_guid)
template<class T >
bool	service_query_t (service_ptr_t< T > &p_out)
virtual int	service_release ()=0 throw ()

Additional Inherited Members
Public Types inherited from service_base
typedef service_base	t_interface
Protected Member Functions inherited from service_base
	service_base ()
	~service_base ()

Detailed Description

This class provides abstraction for retrieving visualisation data. Instances of visualisation_stream being created/released serve as an indication for visualisation backend to process currently played audio data or shut down when there are no visualisation clients active.
Use visualisation_manager::create_stream to instantiate.

Definition at line 3 of file vis.h.

Member Function Documentation

visualisation_stream::FB2K_MAKE_SERVICE_INTERFACE	(	visualisation_stream	,
		service_base
	)

virtual bool visualisation_stream::get_absolute_time ( double &  p_value )

pure virtual

Retrieves absolute playback time since last playback start or seek. You typically pass value retrieved by this function - optionally with offset added - to other visualisation_stream methods.

virtual bool visualisation_stream::get_chunk_absolute ( audio_chunk &  p_chunk, double  p_offset, double  p_requested_length  )

pure virtual

Retrieves an audio chunk starting at specified offset (see get_absolute_time()), of specified length.

Returns

False when requested timestamp is out of available range, true on success.

virtual bool visualisation_stream::get_spectrum_absolute ( audio_chunk &  p_chunk, double  p_offset, unsigned  p_fft_size  )

pure virtual

Retrieves spectrum for audio data at specified offset (see get_absolute_time()), with specified FFT size.

Parameters

p_chunk	Receives spectrum data. audio_chunk type is used for consistency (since required functionality is identical to provided by audio_chunk), the data is not PCM. Returned sample count is equal to half of FFT size; channels and sample rate are as in audio stream the spectrum was generated from.
p_offset	Timestamp of spectrum to retrieve. See get_absolute_time().
p_fft_size	FFT size to use for spectrum generation. Must be a power of 2.

Returns

False when requested timestamp is out of available range, true on success.

virtual void visualisation_stream::make_fake_chunk_absolute ( audio_chunk &  p_chunk, double  p_offset, double  p_requested_length  )

pure virtual

Generates fake audio chunk to display when get_chunk_absolute() fails - e.g. shortly after visualisation_stream creation data for currently played audio might not be available yet. Throws std::exception derivatives on failure.

virtual void visualisation_stream::make_fake_spectrum_absolute ( audio_chunk &  p_chunk, double  p_offset, unsigned  p_fft_size  )

pure virtual

Generates fake spectrum to display when get_spectrum_absolute() fails - e.g. shortly after visualisation_stream creation data for currently played audio might not be available yet. Throws std::exception derivatives on failure.

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

• foobar2000/SDK/vis.h