A media timeline track is a JSON [JSON] document. This document MAY be compressed using the MSF_COMPRESSION property (Section 12.1). The document supports two formats: an explicit entry format and a template format. Publishers MAY combine both formats in a single document.
7.1.1. Explicit entry format
The explicit format contains an array of records. Each record consists of an array of three required items, whose ordinal position defines their type:
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The first item holds the media presentation timestamp, expressed as a JSON Number. This value MUST match the media presentation timestamp, expressed as the floor in integral milliseconds, of the first media sample in the referenced Object. Implementers who require increased time precision can parse the retrieved media object itself.
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The second item holds the MOQT Location of the entry, defined as a tuple of the MOQT Group ID and MOQT Object ID, and expressed as a JSON Array of Numbers, where the first number is the Group ID and the second number is the Object ID.
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The third item holds the wallclock time at which the media was encoded, defined as the number of milliseconds that have elapsed since January 1, 1970 (midnight UTC/GMT) and expressed as a JSON Number. For VOD assets, or if the wallclock time is not known, the value SHOULD be 0.
An example media timeline is shown below:
[ [0, [0,0], 1759924158381], [2002, [1,0], 1759924160383], [4004, [2,0], 1759924162385], [6006, [3,0], 1759924164387], [8008, [4,0], 1759924166389] ]