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SMI Tracker Element

Modified on 2015/01/01 21:59 by Administrator Categorized as Elements, Eye Trackers
Element Icon New Element
Category: AddIn: Base Elements
Creator: OkazoLab Team Scope: Parent Event
Owns Snippets: no Usage: Runtime Screen,Snippets

Actions aligned with epochs of the parent event

After OnsetThe element starts analyzing the selected signal
Control Loop stepLatest signal samples is analyzed within the selected analysis window and the signal plot gets updated.
Before OffsetThe element stops analyzing the selected signal


Generic Properties

NameDescriptionAttributesValue TypeProxy Changed Actions
EyeLink settings
Network addressThe network address of a EyeLink computer in IP format: xxx.xxx.xxx.xxx String
Tracking targetIndicates which eye(s) provides radar data for the parent event. If set to binocular, the right eye is used. EL_EYE
Dummy TestingIf true, presence of the Eyelink device is emulated for testing purposes. No real data is received. Boolean
Filter for samplesIf false, the raw positional data will be modified with the calibration parameters only, if true, the current filters will be applied as well. The value affects only samples and the logged data but not the positions used for tracking. Boolean
Samples NumberNumber of Eyelink samples taken in the recent request (made in OnRunning). Int32
Sample timeArray of recent time stamps. Double[]
Left eyeArray of the recent tracked positions for the left eye. clPoint[]
Right eyeArray of the recent tracked positions for the right eye. clPoint[]
Left pupilArray of the recent pupil sizes for the left eye. Single[]
Right pupilArray of the recent pupil sizes for the right eye. Single[]
EDF Logging
Select EDF folder DesignTimeAction
EDF Folder String
Is LoggingTurn on/off logging with EDF file on the EyeLink host computer. Boolean
Include EventsTurn on/off EyeLink events logging in EDF file. Boolean
EDF MessageThe text message that is sent with a time stamp to an EDF file on Send Message action. String
Send MessageSetting to true in a code snippet (when EDF Logging is enabled) initiates sending the current EDF Message to an EDF file. Boolean
Drift Correction
Recalibrate NowIf set to true in a code snippet, the drift correction is performed - the calibration offsets are adjusted to match the current eye position and custom recalibration point. This action can be used for the runtime drift correction. Boolean
Recalibration PointCustom recalibration point for the runtime drift correction. Empty value by default denotes the screen center in any resolution. clPoint
Amount of the lost dataThe total amount of eyetracking data that have been lost due to a perfomance lag, in bytes. If the value greater than 0 after runtime, consider an increase of the memory buffer size UInt64
MaxRefreshTimeLargest time interval between two read-outs that has been registred for the last runtime, in ms UInt64
LastRefreshTimeThe current time interval between two read-outs, in ms UInt64
Buffer sizeSize of a circular memory buffer, in bytes, that is used to store eyetracker data arriving between in two read-outs Int32

+=== Properties inherited from clTrackerElement ===
NameDescriptionConstraintsTypeUpon Runtime Change
GLM Calibration
Run GLM CalibrationRuns the GLM calibration procedure, which calculates two pairs of linear coefficients for mapping of the tracker input into the screen coordinates. The calculated coefficients are automatically applied at runtime. Boolean
Gain XDefines the gain coefficient for the X axis in the GLM calibration model: X='GainX'*x+OffsetX Double
Gain YDefines the gain coefficient for the Y axis in the GLM calibration model: Y=GainY*y+OffsetY Double
Offset XDefines the offset coefficient for the X axis in the GLM calibration model: X=GainX*x+OffsetX Double
Offset YDefines the offset coefficient for the Y axis in the GLM calibration model: Y=GainY*y+OffsetY Double
Drift Correction
Recalibrate NowRuntime command that helps to correct drifts in tracking data.Correction is done by recalibration of the latest tracker position into a custom screen point defined by the 'Recalibration Point' property.nAs result, the offsets of the GLM calibration get adjusted (but not gains) to compensate a drift in further data. Boolean
Recalibration PointDefines the screen point to which the tracker position will be recalibrated on calling 'Recalibrate Now' action. The default auto value always denotes the screen center. clPoint
Log FolderOpens the dialog for selecting a local folder that will hold all tracking logs String
Open Log DesignerOpens a designer window where the log format can be defined. Boolean
Is LoggingDefines whether logging is turn on/off. The value can be changed at any moment at runtime allowing selective logging during the relevant periods only. Boolean
User FieldDefines the custom user data that is added to every line in the log file. The property can be used for recording varying status information (e.g. trial number) together with the tracker data. The string value may contains multiple fields separated by delimiter. StringOnce a string value is assigned, it is added to every new upcoming line in the log until a new assignment is made.

+=== Properties inherited from clElement === Inherited properties of clElement
NameDescriptionConstraintsValue TypeUpon Change
Is EnabledIf set to false the element is completely omitted when the experiment is run.Boolean
TitleTitle of the element.String

The element allows/is capable of doing something in experiments


Short description


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Practical Use

Technique 1

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Technique 2

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 // Check the trial outcome. Result and RT just other user variables
// insert code snippet here..

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