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      <FormatTypes>Audio</FormatTypes>
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      <FormatDescription>This is an outline record only, and requires further details, research or authentication to provide information that will enable users to further understand the format and to assess digital preservation risks associated with it if appropriate. If you are able to help by supplying any additional information concerning this entry, please return to the main PRONOM page and select ‘Add an Entry’.</FormatDescription>
      <BinaryFileFormat>Text</BinaryFileFormat>
      <ByteOrders>
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      <ReleaseDate>
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      <WithdrawnDate>
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      <ProvenanceSourceID>165</ProvenanceSourceID>
      <ProvenanceName>Georgia Tech Research Institute / Georgia Tech Research Institute</ProvenanceName>
      <ProvenanceSourceDate>21 Apr 2011</ProvenanceSourceDate>
      <ProvenanceDescription>Submitted by Georgia Tech Research Institute</ProvenanceDescription>
      <LastUpdatedDate>21 Apr 2011</LastUpdatedDate>
      <FormatNote>
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      <FormatRisk>
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        <IdentifierType>MIME</IdentifierType>
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        <IdentifierType>PUID</IdentifierType>
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        <SignatureNote>You have to check for two or more frames in a row to be sure you are dealing with an mpeg file.  Frame header: MPEG-1, layer I, protected (FFF6h); Bitrate index Sampling Frequency, padding bit (1 byte), Minimum value 10h, maximum value Ebh; Minimum length of frame-3 to maximum length of frame -3; next frame header (FFF6h) repeat</SignatureNote>
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        <SignatureNote>You have to check for two or more frames in a row to be sure you are dealing with an mpeg file.   Frame header: MPEG-1, layer I, unprotected (FFF7h); Bitrate index Sampling Frequency, padding bit (1 byte), Minimum value 10h, maximum value EBh; Minimum length of frame-3 to maximum length of frame -3; next frame header (FFF7h) repeat</SignatureNote>
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        <SignatureNote>You have to check for two or more frames in a row to be sure you are dealing with an mpeg file.  Frame header: MPEG-2, layer I, protected (FFFEh); Bitrate index Sampling Frequency, padding bit (1 byte), Minimum value 10h, maximum value Ebh; Minimum length of frame-3 to maximum length of frame -3; next frame header (FFFEh) repeat</SignatureNote>
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      <InternalSignature>
        <SignatureID>494</SignatureID>
        <SignatureName>MPEG 2 Audio Layer I (unprotected)</SignatureName>
        <SignatureNote>You have to check for two or more frames in a row to be sure you are dealing with an mpeg file.  Frame header: MPEG-2, layer I, unprotected (FFFFh); Bitrate index Sampling Frequency, padding bit (1 byte), Minimum value 10h, maximum value EBh; Minimum length of frame-3 to maximum length of frame -3; next frame header (FFFFh) repeat</SignatureNote>
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      <RelatedFormat>
        <RelationshipType>Is subtype of</RelationshipType>
        <RelatedFormatID>923</RelatedFormatID>
        <RelatedFormatName>MPEG Audio Stream Layer II</RelatedFormatName>
        <RelatedFormatVersion>
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      </RelatedFormat>
    </FileFormat>
    <SearchCriteria>Criteria</SearchCriteria>
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