Class liblsl

Inheritance

liblsl

Namespace: LSL4Unity

Assembly: cs.temp.dll.dll

Syntax

public class liblsl

Fields

DEDUCED_TIMESTAMP

Constant to indicate that a sample has the next successive time stamp.

This is an optional optimization to transmit less data per sample. The stamp is then deduced from the preceding one according to the stream's sampling rate (in the case of an irregular rate, the same time stamp as before will is assumed).

Declaration

public const double DEDUCED_TIMESTAMP = -1

Field Value

Type	Description
Double	Indicate that a sample has the next successive time stamp.

FOREVER

A very large time duration (> 1 year) for timeout values.

Declaration

public const double FOREVER = 32000000

Field Value

Type	Description
Double	A very large time duration (> 1 year).

Remarks

Note that significantly larger numbers can cause the timeout to be invalid on some operating systems (e.g., 32-bit UNIX).

IRREGULAR_RATE

Constant to indicate that a stream has variable sampling rate.

Declaration

public const double IRREGULAR_RATE = 0

Field Value

Type	Description
Double	Indicate that a stream has variable sampling rate.

Methods

CheckError(Int32)

Check an error condition and throw an exception if appropriate.

Declaration

public static void CheckError(int code)

Parameters

Type	Name	Description
Int32	code	The error code.

Exceptions

Type	Condition
TimeoutException	The operation failed due to a timeout.
liblsl.LostException	The stream has been lost.
ArgumentException	An argument was incorrectly specified (e.g., wrong format or wrong length).
liblsl.InternalException	An internal internal error has occurred.
Exception	An unknown error has occurred.

LibraryVersion()

Version of the liblsl library.

The major version is LibraryVersion() / 100; The minor version is LibraryVersion() % 100;

Declaration

public static int LibraryVersion()

Returns

Type	Description
Int32	The library version.

LocalClock()

Obtain a local system time stamp in seconds.

The resolution is better than a millisecond. This reading can be used to assign time stamps to samples as they are being acquired. If the "age" of a sample is known at a particular time (e.g., from USB transmission delays), it can be used as an offset to LocalClock() to obtain a better estimate of when a sample was actually captured. See StreamOutlet::PushSample() for a use case.

Declaration

public static double LocalClock()

Returns

Type	Description
Double	The local system time stamp in seconds.

ProtocolVersion()

Version of the lsl protocol.

The major version is ProtocolVersion() / 100; The minor version is ProtocolVersion() % 100; Clients with different minor versions are protocol-compatible with each other while clients with different major versions will refuse to work together.

Declaration

public static int ProtocolVersion()

Returns

Type	Description
Int32	The protocole version.

ResolveStream(String, Int32, Double)

Resolve all streams that match a given predicate.

Advanced query that allows to impose more conditions on the retrieved streams; the given string is an XPath 1.0 predicate for the info node (omitting the surrounding []'s).

Declaration

public static liblsl.StreamInfo[] ResolveStream(string pred, int minimum = 1, double timeout = 32000000)

Parameters

Type	Name	Description
String	pred	The predicate string, e.g. "`name='BioSemi'`" or "`type='EEG' and starts-with(name,'BioSemi') and count(info/desc/channel)=32`".
Int32	minimum	Optionally return at least this number of streams.
Double	timeout	Optionally a timeout of the operation, in seconds (default: no timeout). If the timeout expires, less than the desired number of streams (possibly none) will be returned.

Returns

Type	Description
liblsl.StreamInfo[]	An array of matching stream info objects (excluding their meta-data), any of which can subsequently be used to open an inlet.

Remarks

ResolveStream(String, String, Int32, Double)

Resolve all streams with a specific value for a given property.

If the goal is to resolve a specific stream, this method is preferred over resolving all streams and then selecting the desired one.

Declaration

public static liblsl.StreamInfo[] ResolveStream(string prop, string value, int minimum = 1, double timeout = 32000000)

Parameters

Type	Name	Description
String	prop	The liblsl.StreamInfo property that should have a specific value (e.g., "name", "type", "SourceId", or "desc/manufaturer").
String	value	The string value that the property should have (e.g., "EEG" as the type property).
Int32	minimum	Optionally return at least this number of streams.
Double	timeout	Optionally a timeout of the operation, in seconds (default: no timeout). If the timeout expires, less than the desired number of streams (possibly none) will be returned.

Returns

Type	Description
liblsl.StreamInfo[]	An array of matching stream info objects (excluding their meta-data), any of which can subsequently be used to open an inlet.

ResolveStreams(Double)

Resolve all streams on the network.

This function returns all currently available streams from any outlet on the network. The network is usually the subnet specified at the local router, but may also include a multicast group of machines (given that the network supports it), or list of hostnames. These details may optionally be customized by the experimenter in a configuration file (see Network Connectivity in the LSL wiki). This is the default mechanism used by the browsing programs and the recording program.

Declaration

public static liblsl.StreamInfo[] ResolveStreams(double waitTime = 1)

Parameters

Type	Name	Description
Double	waitTime	The waiting time for the operation, in seconds, to search for streams.

Returns

Type	Description
liblsl.StreamInfo[]	An array of stream info objects (excluding their desc field), any of which can subsequently be used to open an inlet. The full info can be retrieve from the inlet.

Remarks

If [waitTime] is too short (less than 0.5s) only a subset (or none) of the outlets that are present on the network may be returned.