VAST tracking events / Linear
VAST firstQuartile tracking event
Short answer: Fires when linear playback reaches 25 percent of Duration.
When it fires
The playhead has reached one quarter of the declared Duration. A gap from start to firstQuartile usually means the media file stalled. A tag with an impression and no quartiles cannot tell a played ad from a fetched one.
Where it is valid
| 2.0 | 3.0 | 4.0 | 4.1+ |
|---|---|---|---|
| Yes | Yes | Yes | Yes |
Legal containers: Linear. An event in the wrong container is not a player error. It is a URL nobody calls.
Using it in a tag
<TrackingEvents>
<Tracking event="firstQuartile">
<![CDATA[https://track.example.com/firstQuartile]]>
</Tracking>
</TrackingEvents>VAST XML fragment only. This excerpt belongs inside a complete VAST document, so standalone validation will fail until it is wrapped in a full <VAST>response.
Related vastlint rules
- VAST-2.0-linear-tracking-quartiles: <Linear> has no standard quartile tracking events — measurement system receives no signal
- VAST-4.1-tracking-event-value: Tracking event attribute not in the valid set for this VAST version
Related events
- start: Fires when linear playback actually begins, first frame rendered.
- midpoint: Fires when linear playback reaches 50 percent of Duration.
- thirdQuartile: Fires when linear playback reaches 75 percent of Duration.
- complete: Fires when linear playback reaches the end of Duration.
Check the XML, then confirm the beacons fire
Validate the event names and containers on the document. Test a live URL when the XML is clean and reporting is still empty.