Class for writing GDF files to disc. More...

#include <Writer.h>

Inheritance diagram for gdf::Writer:

Collaboration diagram for gdf::Writer:

Public Member Functions
	Writer ()
	Constructor.
virtual	~Writer ()
	Destructor.
void	open (const int flags=writer_ev_file)
	Opens file for writing and writes Header.
void	open (const std::string filename, const int flags=writer_ev_file)
	Opens file for writing and writes Header.
void	close ()
	Close file.
bool	isOpen ()
	Check if file is open.
void	setFilename (std::string filename)
	set filename for later opening
void	setMaxFullRecords (size_t num)
	Set number of full records that are kept in memory before the buffer is flushed.
bool	createSignal (size_t index, bool throwexc=false)
	Create a signal.
void	swapSignals (size_t a, size_t b)
	Swap to signals.
void	relocateSignal (size_t src, size_t dst)
	Change signal index.
size_t	getFirstFreeSignalIndex ()
	get lowest signal index that can be created
void	blitFromSerialBufferPhys (const double *buf, const std::vector< size_t > &samples_per_channel)
	Blit data from a serial buffer.
void	addSamplePhys (const size_t channel_idx, const float64 value)
	Add sample in physical units to a channel.
template<typename T >
void	addSampleRaw (const size_t channel_idx, const T value)
	Add a raw sample to channel.
void	blitSamplesPhys (const size_t channel_idx, const float64 *values, size_t num)
	Blit a number of samples in physical units to channel.
void	blitSamplesPhys (const size_t channel_idx, const std::vector< float64 > &values)
	Blit a number of samples in physical units to channel.
template<typename T >
void	blitSamplesRaw (const size_t channel_idx, const T *values, size_t num)
	Blit a number of raw samples to channel.
template<typename T >
void	blitSamplesRaw (const size_t channel_idx, const std::vector< T > &values)
	Blit a number of raw samples to channel.
void	addRecord (Record *r)
	Add a complete Record.
Record *	acquireRecord ()
	Get pointer to a fresh Record.
void	writeRecordDirect (Record *r)
	writes record to disc
void	flush ()
	writes all full records from buffer to disc
void	setEventMode (uint8 mode)
	Set Event Mode.
void	setEventSamplingRate (float32 fs=-1)
	Set Sampling Rate associated with event positions.
void	addEvent (const Mode1Event &ev)
	Add a Mode 1 Event.
void	addEvent (uint32 position, uint16 type)
	Add a Mode 1 Event.
void	addEvent (const Mode3Event &ev)
	Add a Mode 3 Event.
void	addEvent (uint32 position, uint16 type, uint16 channel, uint32 duration)
	Add a Mode 3 Event.
void	addEvent (uint32 position, uint16 type, uint16 channel, float32 value)
	Add a Mode 3 Event.
const GDFHeaderAccess &	getHeaderAccess_readonly () const
	get Constant reference to header access
GDFHeaderAccess &	getHeaderAccess ()
	get reference to main header
const MainHeader &	getMainHeader_readonly () const
	get Constant reference to main header
MainHeader &	getMainHeader ()
	get reference to main header
const SignalHeader &	getSignalHeader_readonly (size_t idx) const
	get constant reference to a signal's header
size_t	getNumSignals () const
SignalHeader &	getSignalHeader (size_t idx)
	get reference to a signal's header

Detailed Description

Class for writing GDF files to disc.

Events are buffered and appended to the file when calling close( ). By default events are buffered in a separate file named filename.events. Thus, information may be recovered after computer crashes during long online recordings. The user may chose to buffer events in memory instead (see open()).

Definition at line 44 of file Writer.h.

Member Function Documentation

void gdf::Writer::addSamplePhys	(	const size_t	channel_idx,
		const float64	value
	)

Add sample in physical units to a channel.

The sample value is converted from the channels [physmin,physmax] to the range of [digmin,digmax] and then cast to the correct data type.

Parameters:

[in]	channel_idx	index of the channel written to
[in]	value	sample value in physical units

Definition at line 249 of file Writer.cpp.

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template<typename T >

void gdf::Writer::addSampleRaw	(	const size_t	channel_idx,
		const T	value
	)		`[inline]`

Add a raw sample to channel.

The sample value is cast to the correct data type, but no range checking is performed

Parameters:

[in]	channel_idx	index of the channel written to
[in]	value	raw sample value in physical units

Definition at line 140 of file Writer.h.

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void gdf::Writer::blitFromSerialBufferPhys	(	const double *	buf,
		const std::vector< size_t > &	samples_per_channel
	)

Blit data from a serial buffer.

Instead of streaming samples as they come, the complete data is provided in an array of type double. In the buffer channels have to be arranged sequentially. I.e. all samples from channel 1 are followed by all samles from channel 2, and so on. This function attempts to keep memory overhead low by filling record by record whenever possible.

Parameters:

[in]	buf	Buffer
[in]	samples_per_channel	A vector containing the number of samples in each channel.

Definition at line 218 of file Writer.cpp.

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void gdf::Writer::blitSamplesPhys	(	const size_t	channel_idx,
		const float64 *	values,
		size_t	num
	)

Blit a number of samples in physical units to channel.

The sample values are converted from the channels [physmin,physmax] to the range of [digmin,digmax] and then cast to the correct data type.

Parameters:

[in]	channel_idx	index of the channel written to
[in]	values	array of sample values in physical units
[in]	num	number of samples to blit

Definition at line 259 of file Writer.cpp.

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void gdf::Writer::blitSamplesPhys	(	const size_t	channel_idx,
		const std::vector< float64 > &	values
	)

Blit a number of samples in physical units to channel.

The sample values are converted from the channels [physmin,physmax] to the range of [digmin,digmax] and then cast to the correct data type.

Parameters:

[in]	channel_idx	index of the channel written to
[in]	values	vector of sample values in physical units

Definition at line 269 of file Writer.cpp.

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template<typename T >

void gdf::Writer::blitSamplesRaw	(	const size_t	channel_idx,
		const T *	values,
		size_t	num
	)		`[inline]`

Blit a number of raw samples to channel.

The sample values are cast to the correct data type, but no range checking is performed

Parameters:

[in]	channel_idx	index of the channel written to
[in]	values	array of raw sample value
[in]	num	number of samples to blit

Definition at line 171 of file Writer.h.

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template<typename T >

void gdf::Writer::blitSamplesRaw	(	const size_t	channel_idx,
		const std::vector< T > &	values
	)		`[inline]`

Blit a number of raw samples to channel.

The sample values are cast to the correct data type, but no range checking is performed

Parameters:

[in]	channel_idx	index of the channel written to
[in]	values	vector of raw sample value

Definition at line 182 of file Writer.h.

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void gdf::Writer::close ( )

Close file.

File is closed if open. Prior to closing, events are written to the file.

Definition at line 122 of file Writer.cpp.

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bool gdf::Writer::createSignal	(	size_t	index,
		bool	throwexc = `false`
	)

Create a signal.

Signals have to be created before they can be configured and stored.

Parameters:

[in]	index	index of the signal
[in]	throwexc	if true, exception::signal_exists may be thrown

Returns:: true on success

Definition at line 186 of file Writer.cpp.

void gdf::Writer::open ( const int flags = writer_ev_file )

Opens file for writing and writes Header.

Prior to opening the file, GDFHeaderAccess::sanitize() is called. Exceptions thrown by GDFHeaderAccess::sanitize() are checked if there are errors and/or warnings. In the presence of errors the exception is forwarded immediately, and in case of warnings the file is opened but the exception is still forwarded. If the file exists, it is not opened unless the file_overwrite flag is set.

Parameters:

[in] flags Flags...

Exceptions:

exception::header_issues
exception::file_exists

Definition at line 47 of file Writer.cpp.

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void gdf::Writer::open	(	const std::string	filename,
		const int	flags = `writer_ev_file`
	)

Opens file for writing and writes Header.

Convenience function. Calls setFilename prior to opening the file

Parameters:

[in]	filename	Full path name to the file.
[in]	flags	Flags...

Exceptions:

exception::header_issues
exception::file_exists

Definition at line 113 of file Writer.cpp.

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void gdf::Writer::relocateSignal	(	size_t	src,
		size_t	dst
	)

Change signal index.

The new index must not exist

Parameters:

[in]	src	old index of first signal
[in]	dst	new index of second signal

Definition at line 202 of file Writer.cpp.

void gdf::Writer::setEventMode ( uint8 mode )

Set Event Mode.

mode can be 1 or 3 1: (default) Events are stored as position,type pairs 3: Events are stored with position and type, associated to a channel and have a duration or value.

Parameters:

[in] mode event mode

Definition at line 334 of file Writer.cpp.

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void gdf::Writer::setEventSamplingRate ( float32 fs = -1 )

Set Sampling Rate associated with event positions.

Events are not actually sampled, but their position is stored in samples rather than seconds. In order to convert event positions between time and sample, this sampling rate is used. If Sampling rate is not set (or set to <= 0 ), fs is set to the highest signal sampling rate.

Parameters:

[in] fs sampling rate

Definition at line 344 of file Writer.cpp.

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void gdf::Writer::setFilename ( std::string filename )

set filename for later opening

Parameters:

[in] filename Full path name to the file

Definition at line 170 of file Writer.cpp.

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void gdf::Writer::setMaxFullRecords ( size_t num )

Set number of full records that are kept in memory before the buffer is flushed.

Parameters:

[in] num number of records

Definition at line 178 of file Writer.cpp.

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void gdf::Writer::swapSignals	(	size_t	a,
		size_t	b
	)

Swap to signals.

Both signals must exist.

Parameters:

[in]	a	index of first signal
[in]	b	index of second signal

Definition at line 194 of file Writer.cpp.

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

Public Member Functions

Detailed Description

Member Function Documentation