essenceTrackEncoding identifies how the actual information in an instantiation is compressed, interpreted, or formulated using a particular scheme. Identifying the encoding used is beneficial for a number of reasons, including as a way to achieve reversible compression; for the construction of document indices to facilitate searching and access; or for efficient distribution of the information across data networks with differing bandwidths or pipeline capacities. Human-readable encoding value should be placed here. Use @ref to identify the codec ID.

Best practice: Use @source to describe the type of encoding reference used, such as fourcc. In @ref, use a URI/URL from the source to identify the codec utilized by its container format.

essenceTrackEncoding 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. Different elements will use the source attribute slightly differently. 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.


essenceTrackEncoding contains no subelements.

Controlled Vocabularies

PBCore essenceTrackEncoding (recommended)
EBU Video Compression Code
Wikipedia List of codecs
IPTC NewsCodes video codec
IPTC NewsCodes audio codec


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