<?xml version="1.0" encoding="utf-8"?>
<PRONOM-Report xmlns="http://pronom.nationalarchives.gov.uk">
  <report_format_detail>
    <FileFormat>
      <FormatID>1255</FormatID>
      <FormatName>ISO 9660 Disk Image File</FormatName>
      <FormatVersion>
      </FormatVersion>
      <FormatAliases>
      </FormatAliases>
      <FormatFamilies>
      </FormatFamilies>
      <FormatTypes>Aggregate</FormatTypes>
      <FormatDisclosure>
      </FormatDisclosure>
      <FormatDescription>ISO 9660 Disk Image File is a virtual image of optical disk, storing content and structure of an optical disc which can be transferred on the other media. This format specifically uses ISO 9660, a so-called original standard for file system for optical disc media, written by International Organization for Standardization (ISO) and considered an international technical standard available for many operating systems. A disk image is a uncompressed copy of the contents of a disk or a folder, it can facilitate certain types of backup and recovery strategies. Please see ID: fdd000348 from Library of Congress and other the links attached to this entry for further information.</FormatDescription>
      <BinaryFileFormat>
      </BinaryFileFormat>
      <ByteOrders>
      </ByteOrders>
      <ReleaseDate>
      </ReleaseDate>
      <WithdrawnDate>
      </WithdrawnDate>
      <ProvenanceSourceID>1</ProvenanceSourceID>
      <ProvenanceName>Digital Preservation Department / The National Archives</ProvenanceName>
      <ProvenanceSourceDate>25 Oct 2012</ProvenanceSourceDate>
      <ProvenanceDescription>08/2023 (v.113)- Max-offset modified for the BOF signature to allow for more exact signature identification. Internally researched.</ProvenanceDescription>
      <LastUpdatedDate>15 Aug 2023</LastUpdatedDate>
      <FormatNote>http://fileformats.archiveteam.org/wiki/ISO_image

https://www.loc.gov/preservation/digital/formats/fdd/fdd000348.shtml

https://en.wikipedia.org/wiki/Optical_disc_image

https://docs.microsoft.com/en-us/windows/win32/imapi/disc-formats</FormatNote>
      <FormatRisk>
      </FormatRisk>
      <TechnicalEnvironment>
      </TechnicalEnvironment>
      <FileFormatIdentifier>
        <Identifier>fmt/468</Identifier>
        <IdentifierType>PUID</IdentifierType>
      </FileFormatIdentifier>
      <ExternalSignature>
        <ExternalSignatureID>1275</ExternalSignatureID>
        <Signature>iso</Signature>
        <SignatureType>File extension</SignatureType>
      </ExternalSignature>
      <ExternalSignature>
        <ExternalSignatureID>3131</ExternalSignatureID>
        <Signature>toast</Signature>
        <SignatureType>File extension</SignatureType>
      </ExternalSignature>
      <ExternalSignature>
        <ExternalSignatureID>3132</ExternalSignatureID>
        <Signature>cdr</Signature>
        <SignatureType>File extension</SignatureType>
      </ExternalSignature>
      <ExternalSignature>
        <ExternalSignatureID>3133</ExternalSignatureID>
        <Signature>dmg</Signature>
        <SignatureType>File extension</SignatureType>
      </ExternalSignature>
      <ExternalSignature>
        <ExternalSignatureID>3134</ExternalSignatureID>
        <Signature>bin</Signature>
        <SignatureType>File extension</SignatureType>
      </ExternalSignature>
      <InternalSignature>
        <SignatureID>730</SignatureID>
        <SignatureName>k k Image File</SignatureName>
        <SignatureNote>BOF: CD001{1-16384}ÿCD001 with offset of (32700- 37700).
Beginning at byte 32768, an ISO file will hold two-to-many volume descriptors, each of 2048 bytes and starting with '*CD001', where * represents the volume desciptor type as defined within the specification.</SignatureNote>
        <ByteSequence>
          <ByteSequenceID>919</ByteSequenceID>
          <PositionType>Absolute from BOF</PositionType>
          <Offset>32700</Offset>
          <MaxOffset>37700</MaxOffset>
          <IndirectOffsetLocation>
          </IndirectOffsetLocation>
          <IndirectOffsetLength>
          </IndirectOffsetLength>
          <Endianness>
          </Endianness>
          <ByteSequenceValue>4344303031{1-16384}FF4344303031</ByteSequenceValue>
        </ByteSequence>
      </InternalSignature>
      <RelatedFormat>
        <RelationshipType>Has lower priority than</RelationshipType>
        <RelatedFormatID>1603</RelatedFormatID>
        <RelatedFormatName>Encase Image File/Expert Witness Compression File</RelatedFormatName>
        <RelatedFormatVersion>
        </RelatedFormatVersion>
      </RelatedFormat>
      <RelatedFormat>
        <RelationshipType>Has lower priority than</RelationshipType>
        <RelatedFormatID>2585</RelatedFormatID>
        <RelatedFormatName>UDF-ISO 9660 Bridge Disc</RelatedFormatName>
        <RelatedFormatVersion>
        </RelatedFormatVersion>
      </RelatedFormat>
      <RelatedFormat>
        <RelationshipType>Has lower priority than</RelationshipType>
        <RelatedFormatID>2586</RelatedFormatID>
        <RelatedFormatName>Apple Partition Map Disk Image</RelatedFormatName>
        <RelatedFormatVersion>
        </RelatedFormatVersion>
      </RelatedFormat>
      <RelatedFormat>
        <RelationshipType>Has lower priority than</RelationshipType>
        <RelatedFormatID>2587</RelatedFormatID>
        <RelatedFormatName>Apple Partition Map ISO 9660 Hybrid</RelatedFormatName>
        <RelatedFormatVersion>
        </RelatedFormatVersion>
      </RelatedFormat>
      <RelatedFormat>
        <RelationshipType>Has priority over</RelationshipType>
        <RelatedFormatID>2589</RelatedFormatID>
        <RelatedFormatName>Nero Burning ROM Image File</RelatedFormatName>
        <RelatedFormatVersion>Generic</RelatedFormatVersion>
      </RelatedFormat>
      <RelatedFormat>
        <RelationshipType>Is subtype of</RelationshipType>
        <RelatedFormatID>2584</RelatedFormatID>
        <RelatedFormatName>UDF Disc Image</RelatedFormatName>
        <RelatedFormatVersion>
        </RelatedFormatVersion>
      </RelatedFormat>
    </FileFormat>
    <SearchCriteria>Criteria</SearchCriteria>
  </report_format_detail>
</PRONOM-Report>
