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Digital Cinema Initiative Distribution Package (DCP), Version 1.0

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Format Description Properties Explanation of format description terms

Identification and description Explanation of format description terms

Full name Digital Cinema Initiative Package (DCP). Described in the Digital Cinema System Specification v1.0, July 20, 2005
Description

The DCP is a set of encrypted files representing digital moving image content packaged for shipment to theaters. The DCP is based on the DCDM_1_0, and its files or tracks contain images, audio, subpictures and/or timed text, and auxiliary data. Only the image track is compressed in the DCP; see Notes below. The DCP consists of the package itself (with all of the track files) and a separate XML Packing List that identifies and includes file-integrity checks ("hash") for each file, as well as a public key and digital signature that is part of the overall security system.

The overall Digital Cinema Initiative (DCI) system specification defines a life cycle in which content exists in a succession of states:

  • DSM. Content originates as a Digital Source Master; format selected by producer, not specified
  • DCDM_1_0. Content is shaped into a Digital Cinema Distribution Master, covered by the specification
  • DCP. Content is compressed and encrypted for transport to the theater as a Digital Cinema Package, covered by the specification
  • DCDM (again). Content is unpackaged, decrypted, and decompressed at the theater for exhibition.

The overall system specification devotes considerable space to the required capabilities for playback and projection systems in theaters, and regarding security and content protection.

Production phase Final-state for use in a distribution chain; may also serve as a middle-state format for archiving.
Relationship to other formats
    May contain MXF_OP1a_JP2_LSY, MXF File, OP1a, Lossy JPEG 2000 in Generic Container
    May contain DCDM_1_0, Digital Cinema Initiative Distribution Master, Version 1.0
    Has earlier version Draft versions of overall specification: Digital Cinema System Specification v4.2 (August 2004), v4.3 (December 2004), v5.0 (March 2005), v5.1 (April 2005), and v5.2 (June 2005), not documented at this time

Local use Explanation of format description terms

LC experience or existing holdings None
LC preference None

Sustainability factors Explanation of format description terms

Disclosure Fully disclosed. Developed by the Digital Cinema Initiatives. [See Notes below for information on the relationship of the DCI to the SMPTE DC28 standards-development process.]
    Documentation The DCP is one element defined in the Digital Cinema System Specification v5.2, June 2005. The specification is accessible to members at the Digital Cinema Initiatives Web site.
Adoption The digital distribution of movies has been adopted rapidly in the United States following the SMPTE standardization of DCP. See for example, "The ABCs of DCPs: Unwrapping the Digital Cinema Package" an article from the theater operator's point of view and states "the studios will cease 35mm distribution by 2015; the buzz is that 90% of U.S. theatres will be digital by 2013; and back in January there were more digital than 35mm theatre screens."
    Licensing and patents None identified. The specification includes a disclaimer: "Compliance with this document may require use of one or more features covered by proprietary rights . . . no position is taken by DCI with respect to the validity of any patent of other proprietary right." (p. vii)
Transparency The Packing List will be transparent. The package itself will be compressed and encrypted and not transparent; like a ZIP file, the DCP exists to support the movement of data. The encryption method for non-interleaved MXF frame-wrapped tracks is defined in SMPTE 429-6:2006. The algorithm and mode for the KLV encrypted triplets is defined in the Cipher Algorithm metadata item within the Cryptographic Context Set. The default is Advanced Encryption Standard (AES) cipher as defined by NIST SP 800-38a.
Self-documentation     The Packing List identifies each file, includes file-integrity checks ("hash") for each file, as well as a public key and digital signature that is part of the overall security system. Optional "MIC" (media content integrity) hash values can be created at the KLV triplet level using a structure which parallels that for encryption defined in SMPTE 429-6:2006. The MIC value within the KLV triplet is calculated only on the V portion of triplet - not the K and L.  The hash algorithm type is defined in the "MIC Algorithm" metadata item within the Cryptographic Context Set. The default algorithm is SHA-1. The actual hash value is stored on the "MIC" metadata item within the Encrypted Triplet Variable Length Pack.    
External dependencies See DCDM_1_0
Technical protection considerations Employs a public-private key, signature based system.

Quality and functionality factors Explanation of format description terms

Moving Image
Normal rendering Not relevant; see DCDM_1_0
Clarity (high image resolution) Not relevant; see DCDM_1_0
Functionality beyond normal rendering Not relevant; see DCDM_1_0
Sound
Normal rendering Not relevant; see DCDM_1_0
Fidelity (high audio resolution) Not relevant; see DCDM_1_0
Multiple channels Not relevant; see DCDM_1_0
Functionality beyond normal rendering Not investigated at this time.

File type signifiers Explanation of format description terms

Tag Value Note
Filename extension Not applicable.   
Internet Media Type Not applicable.   
Magic numbers Not applicable.   

Notes Explanation of format description terms

General In the DCDM_1_0, the image track consists of uncompressed data mapped to the MXF Generic Container in accord with SMPTE standard 384M, using the frame wrapping method. In the DCP, the image track consists of lossy JPEG 2000 data mapped to the MXF Generic Container in accord with SMPTE standard 422M, and using JPEG 2000 codestreams conforming to J2K_C_Profile_3 (for 2K) and J2K_C_Profile_4 (for 4K).
History

From the Digital Cinema Initiatives Web site: "Digital Cinema Initiatives, LLC (DCI) was created in March 2002, as a joint venture of Disney, Fox, MGM, Paramount, Sony Pictures Entertainment, Universal and Warner Bros. Studios. DCI's primary purpose is to establish and document voluntary specifications for an open architecture for digital cinema that ensures a uniform and high level of technical performance, reliability and quality control. DCI will also facilitate the development of business plans and strategies to help spur deployment of digital cinema systems in movie theaters."

The formal standardization of DCI specifications is being overseen by the SMPTE technology committee DC28, made up of four working groups preparing more than 20 separate items. The relationship of this to the Digital Cinema Initiative (and a European counterpart) was articulated in 2006 by the European Federation of Cinematographers: "The establishment of a new standard for the future digital cinema projection copy has been delegated to the SMPTE [DC28 technology committee]. Both DCI (Digital Cinema Initiatives) and EDCF-T (European Digital Cinema Forum - Technical Module) are input bodies towards SMPTE DC28. . . .  Now that the DCI published their specifications it is to expect that the standardization work at SMPTE will accelerate and it is possible that SMPTE may finalize the standard in less than a year from now."


Format specifications Explanation of format description terms


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Last Updated: 03/13/2014