Different versions of a track are described by different <feed> elements each identified with a unique vuid attribute. In a Gateway clip XML, a specific version of a clip is defined as all the <feed> elements sharing the same vuid attribute accross different <track> elements.
The <version> element describes and lists the available versions, while the currentVersion attribute defines which <version> element is the current one. The client application that reads the .clip is not required to currentVersion; it only serves as a flag put there by the creator.
<tracks> <track uid="track1"> <feeds> <feed vuid="v1" uid="t1f1"/> <feed vuid="v3" uid="t1f2"/> <!-- version 3 of the track, version 2 was never created --> </feeds> </track> <track uid="track2"> <feeds> <feed vuid="v1" uid="t2f1"/> <feed vuid="v2" uid="t2f2"/> <feed vuid="v3" uid="t2f3"/> </feeds> </track> </tracks>
<versions currentVersion="v2"> <version uid="v1"/> <version uid="v2"/> <version uid="v3"/> </versions>
|Attribute||Description||Data Type||Allowed Values||Attribute is...|
|type||The data type of the element.||character data||versions||Implied|
|version||Version of the xml element.||unsigned integer||3||Implied|
|currentVersion||Defines the current version of the clip, as set by the client application that created the file. The client application is expected to view this version as the most up-to-date. |
If not defined, the Gateway considers the last <version> element defined in the file as the current version.
|IDREF||any existing one uid from an enclosed <version> element.||Implied|