essenceTrackTimeStart provides a time stamp for the beginning point of playback for a time-based essence track. It is likely that the content on a tape may begin an arbitrary amount of time after the beginning of the instantiation.

Best practice: Use in combination with essenceTrackDuration to identify a sequence or segment of an essence track that has a fixed start time and end time. Best practice is to use a timestamp format such as HH:MM:SS[:|;]FF or HH:MM:SS.mmm or S.mmm.

essenceTrackTimeStart can only be contained by instantiationEssenceTrack.

Usage: optional, not repeatable.


  • source – optional. The source attribute provides the name of the authority used to declare the value of the element. For example, identifier source (required) should be the name of the organization, institution, system or namespace that the identifier came from, such as “PBS NOLA Code” or an institutional database identifier. For other elements, this might be the name of a controlled vocabulary, namespace or authority list, such as Library of Congress Subject Headings. We recommend a consistent and human readable use.
  • ref – optional. The ref attribute is used to supply a source’s URI for the value of the element. Attribute ref can be used to point to a term in a controlled vocabulary, or a URI associated with a source.
  • version optional. The version attribute identifies any version information about the authority or convention used to express data of this element.
  • annotation – optional. The annotation attribute includes narrative information intended to clarify the nature of data used in the element. This attribute can be used as a notes field to include any additional information about the element or associated attributes.


essenceTrackTimeStart contains no subelements.


Submit any issues or suggested changes for future schema iterations by creating a ticket in our Github repository.