Read the MPD hierarchy before resolving media resources

The useful distinctions

• An MPD uses the DASH MPD namespace.
• Periods contain adaptation sets.
• Representations describe media alternatives within adaptation sets.

Identify the parent context of each value

An attribute read from an adaptation set has a different scope from one attached to a single representation. Begin an inspection by writing the nesting path before extracting values. In the invented document, the audio media type is declared on the adaptation set while the bitrate and codec are attached to its one representation. Keeping that parent context prevents a report from assigning a property to every track when it was only attached to one.

Keep schema checks separate from media checks

A namespaced XML document can be well formed, schema conforming, and still refer to unavailable or unsuitable media. Those are separate validation stages. This example supplies a minimal synthetic audio presentation so the grouping is easy to see; the single BaseURL names a hypothetical on-demand resource rather than embedding media. An actual profile review would also examine container indexing and the selected addressing model. Do not infer successful playback from the presence of familiar element names. For automated inspection, use namespace-aware element selection rather than matching a literal prefix, because different prefix spellings can represent the same namespace identity. An inventory for this document has one row per representation with its parent Period and AdaptationSet identifiers or positions. That preserves grouping information if the inventory is later exported into a flat spreadsheet.

Worked example · synthetic

The document is a synthetic MPD structure. It declares one Period, one AdaptationSet, and one Representation; the referenced resource and its profile-specific indexing remain unverified.

Synthetic text example; no network operation has been performed.

<MPD xmlns="urn:mpeg:dash:schema:mpd:2011" type="static"
     profiles="urn:mpeg:dash:profile:isoff-on-demand:2011"
     mediaPresentationDuration="PT8S" minBufferTime="PT1S">
  <Period duration="PT8S">
    <AdaptationSet mimeType="audio/mp4">
      <Representation id="audio-main" bandwidth="96000" codecs="mp4a.40.2">
        <BaseURL>audio.mp4</BaseURL>
      </Representation>
    </AdaptationSet>
  </Period>
</MPD>

Check the interpretation

• Use namespace-aware XML parsing.
• Retain the parent scope of each property.
• Do not equate XML schema validity with a complete media-profile test.