s can be partially encrypted, specified by subsample information
        referenced by SampleAuxiliaryInformationSizesBox ('saiz') and
        SampleAuxiliaryInformationOffsetsBox ('saio') boxes.
      </p>
      <p>For complete information, see [[CENC]].</p>
    </section>

    <section id="init-data">
      <h2>Initialization Data Extraction</h2>
      <p>
        Streams may contain one or more Protection System Specific Header
        ('pssh') boxes [[CENC]], each for a unique SystemID, at each location