Home › Forums › Legacy SDKs › Visualising calibration results with Gaze SDK › Reply To: Visualising calibration results with Gaze SDK
The Tobii Gaze SDK does not include a tool or code sample for visualization of the calibration result, but it can provide you with the data you need to create one yourself.
The developer’s guide includes an image of how a calibration plot visualization can look, and the image is based on the kind of calibration plot visualization that is familiar for many users of certain Tobii software products.
To create a similar visualization you need to get the newly computed and set calibration from the eye tracker and then extract the necessary data for each calibration point.
In the Gaze SDK for .Net you can retrieve a calibration from the eye tracker as a Calibration object using either the GetCalibration or the GetCalibrationAsync method. On the Calibration object you can call GetCalibrationPointDataItems to get an IEnumerable of CalibrationaPointData structs that gives you the information you need for each calibration point to create a visualization and the kind of re-calibration functionality that you listed above.
Here is a list of the available data in the CalibrationPointData struct:
- TruePosition – The point on the screen where the calibration stimulus was displayed.
- LeftMapPosition – The left eye’s gaze point on the screen after calibration.
- RightMapPosition – The right eye’s gaze point on the screen after calibration.
- LeftStatus – Information about the validity and usage of the left eye data.
- RightStatus – Information about the validity and usage of the right eye data.
You can create a calibration plot visualization like the one in the developer’s guide by calculating and drawing the offset vectors between the true position and the mapped position of each eye.
You can use the status information to indicate in the GUI to the participant/operator which calibration point needs re-calibration.
Please, take a look also at the WpfCalibrationSample for an example how to create a GUI for a calibration procedure.