webgazer-calibrate¶
This plugin can be used to calibrate the WebGazer extension. For a narrative description of eye tracking with jsPsych, see the eye tracking overview.
Parameters¶
In addition to the parameters available in all plugins, this plugin accepts the following parameters. Parameters with a default value of undefined must be specified. Other parameters can be left unspecified if the default value is acceptable.
| Parameter | Type | Default Value | Description |
|---|---|---|---|
| calibration_points | array | [[10,10], [10,50], [10,90], [50,10], [50,50], [50,90], [90,10], [90,50], [90,90]] |
Array of points in [x,y] coordinates. Specified as a percentage of the screen width and height, from the left and top edge. The default grid is 9 points. |
| calibration_mode | string | 'click' |
Can specify click to have subjects click on calibration points or view to have subjects passively watch calibration points. |
| repetitions_per_point | numeric | 1 | The number of times to repeat the sequence of calibration points. |
| point_size | numeric | 20 | Diameter of the calibration points in pixels. |
| randomize_calibration_order | bool | false |
Whether to randomize the order of the calibration points. |
| time_to_saccade | numeric | 1000 | If calibration_mode is set to view, then this is the delay before calibrating after showing a point. Gives the participant time to fixate on the new target before assuming that the participant is looking at the target. |
| time_per_point | numeric | 1000 | If calibration_mode is set to view, then this is the length of time to show a point while calibrating. Note that if click calibration is used then the point will remain on the screen until clicked. |
Data Generated¶
In addition to the default data collected by all plugins, this plugin collects the following data for each trial.
| Name | Type | Value |
|---|---|---|
No data currently added by this plugin. Use the webgazer-validate plugin to measure the precision and accuracy of calibration.
Simulation Mode¶
This plugin does not yet support simulation mode.
Example¶
Because the eye tracking plugins need to be used in conjunction with each other, please see the example on the eye tracking overview page for an integrated example.