onEvent attribute

The onEvent attribute specifies expressions to be evaluated when the video frame corresponding to eventTime has been presented.

Member of

<video>

Syntax

/ onEvent = { script }

Parameters

Name	Type	Description
script	script	One or more expressions, delimited by semi-colons. See help with expression syntax for more information.

Remarks

This parameter executes a sest of expressions just before a stimulus is readied for presentation. The expressions can read and conditionally update the various properties in the script. This is useful for noting when a specific video frame is presented.

Examples

The following notes the elapsed time within the current trial that the frame occurring at 512 ms into the video called "desparatehousewives.mpg" is presented on the screen:

<video tvshows>
/ items = ("desparatehousewives.mpg")
/ eventTime = 512
/ onEvent = {
 values.marker = script.currentTrial.elapsedTime;
}
/ position = (25, 25)
</video>