International Standard Audiovisual Number (ISAN) is a unique identifier for audiovisual works and related versions, similar to ISBN for books. It was developed within an ISO (International Organization for Standardization) TC46/SC9 working group. ISAN is managed and run by ISAN-IA. Overview The ISAN standard (ISO standard 15706:2002 & ISO 15706-2) is recommended or required as the audiovisual identifier of choice for producers, studios, broadcasters, Internet media providers and video games publishers who need to encode, track, and distribute video in a variety of formats. It provides a unique, internationally recognized and permanent reference number for each audiovisual work and related versions registered in the ISAN system. The ISO 15706-2 is the ISO standard, an extension to the existing 2002 published standard ISO 15706:2002. The ISO 15706-2 is the Information and documentation ISAN Part 2: Version identifier. ISO 15706-2:2007 specifies the basic systems and procedures to support the issuance and administration of V-ISANs. ISAN identifies works throughout their entire life cycle from conception, to production, to distribution and consumption. ISANs can be incorporated in both digital and physical media, such as theatrical release prints, DVDs, publications, advertising, marketing materials and packaging, as well as licensing contracts to uniquely identify works. The ISAN identifier is incorporated in many draft and final standards such as AACS, DCI, MPEG, DVB, and ATSC. The identifier can be provided under descriptor 13 (0x0D) for Copyright identification system and reference within an ITU-T Rec. H.222 or ISO/IEC 13818 program. Number format The ISAN is a 12 byte block comprising three segments: a 6 byte root, a 2 byte episode or part, and a 4 byte version. uimsbf: unsigned integer, most significant bit first A root is assigned to a core work by the ISAN-IA. If a root has subsequent film parts (i.e., sequels) or television episodes then the root_part is incremented and started at a point defined by the producing studio. (i.e., relates to the production number) If a root_part has been modified in some way—for example, dubbing, 24/30/25 frame conversions and subtitling the work into other languages—can have different versions. Common uses are when the native North American 30/1001 frame version is set to one, the 25 frame conversion for PAL compatible markets is set to two. When the 12 byte ISAN is represented in hexadecimal form it has 24 digits, for example: 000000018947000000000000. However, a printed ISAN designed for human reading always begins with the