Applies to: Protocol and format interpretation for developers inspecting authorized media delivery.
The useful distinctions
- DASH distinguishes static and dynamic MPDs.
- A live-to-VOD transition can reuse existing media segments.
- The resulting archive has a defined presentation interval.
Define the archive interval first
Before reviewing a live-to-static conversion, write down the intended start and end of the archived presentation. The synthetic result declares a twelve-second presentation. That is the interval the publication must consistently describe, including its Periods, media references, and timing. A changed type field alone does not establish that the chosen resources cover that interval or that they are retained for on-demand access.
Review references and timing as a set
If existing live segments are reused, their original media timestamps may still need a coherent mapping into the static presentation. The authoring review should therefore examine offsets, start boundaries, final boundaries, and any gaps together. Availability rules from the live publication should not be casually interpreted as permanent archive guarantees. This short example supplies one Period and a fictional media reference; actual indexing and sample coverage need a separate check. The companion DASH-IF document is explicitly a community-review publication in the version read, so its status belongs in the source note. The article presents a bounded review method rather than asserting that a particular service's conversion or any player behavior has been tested. For the archive fixture, zero and twelve are explicit presentation boundaries in the review worksheet. They should remain visible when comparing which formerly live resources actually cover the proposed archived interval.
Worked example · synthetic
The synthetic MPD declares one twelve-second static Period beginning at zero. Its XML structure can be checked without fetching archive.mp4; conformance of the media and its indexing remains a separate task.
Complete synthetic MPD XML structure; referenced media and profile-specific indexing are not supplied or validated.
<MPD xmlns="urn:mpeg:dash:schema:mpd:2011"
type="static" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011"
mediaPresentationDuration="PT12S" minBufferTime="PT1S">
<Period start="PT0S" duration="PT12S">
<AdaptationSet mimeType="video/mp4">
<Representation id="archive-v1" bandwidth="1000000" codecs="avc1.4d401f">
<BaseURL>archive.mp4</BaseURL>
</Representation>
</AdaptationSet>
</Period>
</MPD>Check the interpretation
- Define the intended archive interval.
- Review final segment coverage and retention.
- Validate referenced media and indexing independently.