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Jenny [Tobii]

Ok, then I understand why you need an alternative way of calibrating. This is possible to achieve using the Tobii Gaze SDK. The Gaze SDK is a low level SDK that requires the application to handle the eye tracker setup and calibration on its own.

You will find samples included in the Gaze SDK that shows you how to do a calibration procedure programmatically. Basically, the procedure is like this:
1) call a function to start the calibration procedure
2) for each calibration point the user is looking at:
2.1) call a function to tell the eye tracker to collect calibration data for the current calibration point
2.2) wait until the eye tracker makes a callback that it has finished collecting data for the point
3) call a function to compute and set the calibration on the eye tracker.

After step 3) the will be a calibration stored on the eye tracker that will stay there until the eye tracker is unplugged from the computer (or loses power supply). It will also be possible to retrieve the newly computed calibration blob from the eye tracker, and store it locally, and to use a separate function to set a given calibration on the eye tracker.

What you need to know is that if there is an EyeX Engine running on the computer, that too will use the Gaze SDK to try and make sure the eye tracker is always set up and ready for use. This means that some type of changes in the computer system will trigger the EyeX Engine to do a revalidation of the eye tracker set up, and during that process reset the calibration to the one stored on the local machine for the currently selected EyeX user profile. In other words, the EyeX Engine will overwrite any calibration set in the eye tracker in certain situations: when a user logs in to the computer (this also applies when switching temporarily between different user logins), when display settings are changed (changing resolution, attaching a new monitor, etc), or when EyeX settings are changed. If you cannot control for the circumstances listed when the EyeX Engine could reset the calibration, your application needs to be run as a stand-alone application using the Gaze SDK, with the EyeX Engine switched off.

You can get access to the Tobii Gaze SDK by following the link on developer.tobii.com/downloads.