Digital Cinema Terminology
For the curious, we've put together a handy list of common and not-so-common digital cinema terminology.
In this article:
Basics
Composition: The name given to the complete digital representation of a title.
Composition Playlist (CPL): The high level playlist that defines the play order of the essence Track Files that make up the Composition.
Digital Cinema Package (DCP): The name given to the collection of motion picture files sent to a cinema. A DCP may not represent a complete motion picture.
Essence: By example, (and without limitation), an essence type could be picture, sound, subtitle and/or caption
Interop DCP: The original implementation of Composition and DCP deployed during the rollout of digital cinema, based on an early draft of this work in SMPTE.
KLV: Key-Length-Value is the data encoding method used in MXF Track Files.
MXF: Material Exchange Format, the file structure used for digital cinema Track Files, containing essence and metadata.
Packing List: The manifest of files carried in a DCP.
Reels: The name given to the collection of Track Files that make up a temporal portion of a title.
SMPTE DCP: The implementation of Composition and DCP standardized by SMPTE.
Track File: A file containing a single essence type. A component of a Composition.
UUID (Universally Unique Identifier), the method for generating identifiers associated with all digital cinema files.
OV Package or OV Composition: Original Version, a name applied to a complete Composition where certain Track Files of the Composition may be shared with other Compositions.
VF Package or VF Composition: Version Files, a name applied to a partial Composition intended to utilize Track Files of an OV Composition. A VF Package can also be thought of as an Asset Package.
Security
Certificate: A data file carrying the public key of an asymmetric or RSA certificate and descriptive metadata.
Encryption: The mathematical modification of data such that it is unrecognizable. Conversion back to its original form requires a “key.”
Forensic Mark: A hidden mark, such as a watermark, in picture or sound. The mark, when decoded, provides identifying information about the location where the picture and sound were experienced.
Key: In encryption, the data value used to either encrypt valuable data, or decrypt valuable data.
KDM: Key Delivery Message. The data message type used to carry encrypted keys to a target player, authorizing the player to decrypt and play the associated encrypted content.
Media Block: A player whose security characteristics and behaviors are fully defined by DCI.
TDL: Trusted Device List. In common use of the term, a TDL is a database of trusted devices in the field, normally maintained by a fulfillment entity. However, it can also refer to the list, incorporated in the KDM, of devices authorized for use with the target media block.
Sound
Soundfield: The sound as experienced by the audience.
Soundfield Group: A collection of sound channels that define a Soundfield.
Sound Format: A distribution format for sound. Typical sound formats are 5.1 Sound, or 7.1 Sound.
Surround Sound: The term applied to sound in the auditorium produced by the speaker system that’s not associated with the screen.
Industry Organizations
DCI: Digital Cinema Initiatives. The consortium of the six major Hollywood studios responsible for the DCI Digital Cinema System Specification and the DCI Compliance Test Plan.
IETF: Internet Engineering Task Force
SMPTE: Society of Motion Picture and Television Engineers