This page covers the Chapter length reporting dimension. See Chapter length for how to collect this variable.
The Chapter length dimension reports the duration of each chapter, in seconds.
How this dimension is populated
Chapter length is set by the player on every chapter start event.
a.media.chapter.length to an eVar.evar1-evar250, post_evar1-post_evar250 (the eVar that your processing rule maps a.media.chapter.length to)c_contextdata.a.media.chapter.lengthClassification approach
Adobe creates the Chapter length classification structure automatically when Media Chapters is enabled for the report suite. You are responsible for populating and maintaining the classification using Classification sets.
This approach provides a guaranteed 1:1 relationship between each chapter ID and its length. Classification updates apply retroactively across all historical data for that ID.
Processing rule approach
Create a Processing rule that maps a.media.chapter.length to an eVar. This approach captures the chapter length as a per-hit value without requiring classification maintenance.
The trade-off is that you lose the guaranteed 1:1 relationship between the chapter length and the parent Chapter dimension. If your implementation sends inconsistent values for the same chapter ID across events, multiple lengths can appear under the same chapter. Updating a value only applies to data moving forward.
Dimension items
Each item is the integer length value, in seconds, reported on chapter start.