Using the Eyelink Eye Tracker in Vizard

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The Eyelink is an eye tracker made by SR Research. This article describes how to get the Eyelink working with Vizard.

1. Download and install the Eyelink Developer's kit:

https://www.sr-support.com/forums/showthread.php?t=6

To access the support site, you will first need to register at:

https://www.sr-support.com

2. Download the win32 version of Pylink:

https://www.sr-support.com/forums/showthread.php?t=14.

Included are several Pylink modules for different versions of Python. For Vizard30 use Pylink24.

3. Download the eyelink_viz.zip file and extract the contents. Place the files inside the Pylink24 folder.

4. Run the Popup Calibration utility. The popup calibration program can be found at Start -> Programs->SR Research->EyeLink->Utilities->Popup Calibration.

Before you start the Popup Calibration, set your desired video mode. Then to calibrate, follow the instructions below.

  • Start Popup Calibration.
  • On Popup Calibration select file->New Session 3.
  • Enter a name for the session, and click ok. (The name can be anything, the name will not be used for the recording in the Vizard script)
  • Select Eyelink->Camera Setup.
  • Once the camera setup is done, quit the popup calibration.

5. Run the eyelink_viz.py file. The script includes the following:

  • eyelink initialization
  • event handlers to startRecording, stopRecording, collectSample and closeConnection

The startRecording and stopRecording functions respond to key inputs of 'r' and 's' respectively. The collectSample function is a timer callback function called every 0.05 seconds. While recording, samples are collected from the tracker and a gaze cursor is drawn on the scene. The closeConnection function is an exit handler.

Note: Line 9 takes the size of the drawing window. So, if you are not in full screen mode, gaze values are for the windowed scene.