Digital Cinema Package

A Digital Cinema Package (DCP) is a collection of digital files used to store and convey digital cinema (DC) audio, image, and data streams.

The term has been defined by Digital Cinema Initiatives, LLC in their recommendations for packaging of DC contents. General practice adopts a file structure that is organized into a number of usually multi-gigabyte size Material eXchange Format (MXF) files, which are separately used to store audio and video streams, and auxiliary index files in XML format.

The MXF track files contain image and audio essence that are compressed and encoded in order to reduce the huge amount of required storage. Encryption is an optional solution and is used to protect from unauthorized use. The image track file contains compressed JPEG 2000 essence and the audio is a wrapped 24-bit linear PCM multichannel WAV file. The adopted (optional) encryption standard is AES 128-bit in CBC mode.

The newer SMPTE standards are used to conform the recommendations among different tool vendors and producers. Interop, the legacy DCP standard, is still required to be supported by DCP players.

The DCP root folder (in the storage medium) contains a number of files, some used to store the image and audio contents, and some other used to organize and manage the whole playlist.

Picture contents may be stored in one or more reels corresponding to one or more MXF files. Each reel contains pictures as MPEG-2 or JPEG 2000 essence, depending on the adopted codec. MPEG-2 is no longer compliant with the DCI specification. JPEG 2000 is the only accepted compression format.

...
Wikipedia