DCI Specs - Digital Cinema Initiatives

1.1. Introduction1. OVERVIEWA number of significant technology developments have occurred in the past few years that haveenabled the digital playback and display of feature films at a level of quality commensurate withthat of 35mm film release prints. These technology developments include the introduction of:high-resolution film scanners, digital image compression, high-speed data networking andstorage, and advanced digital projection. The combination of these digital technologies hasallowed many impressive demonstrations of what is now called “Digital Cinema” Thesedemonstrations, however, have not incorporated all of the components necessary for a broadbasedcommercially viable Digital Cinema system. These demonstrations have created a greatdeal of discussion and confusion around defining the quality levels, system specifications, andthe engineering standards necessary for implementing a comprehensive Digital Cinema system.Digital Cinema Initiatives, LLC (DCI) is the entity created by seven motion picture studios:Disney, Fox, Metro-Goldwyn-Mayer 1 , Paramount Pictures, Sony Pictures Entertainment,Universal Studios, and Warner Bros. Studios. The primary purpose of DCI is to establishuniform specifications for Digital Cinema. These DCI member companies believe that theintroduction of Digital Cinema has the potential for providing real benefits to theater audiences,theater owners, filmmakers and distributors. DCI was created with recognition that thesebenefits could not be fully realized without industry-wide specifications. All parties involved inthe practice of Digital Cinema must be confident that their products and services areinteroperable and compatible with the products and services of all industry participants. The DCImember companies further believe that Digital Cinema exhibition will significantly improve themovie-going experience for the public.1.2. ScopeThe document defines technical specifications and requirements for the mastering of,distribution of, and theatrical playback of Digital Cinema content. The details are in the followingsections:• Digital Cinema Distribution Master (DCDM): This section provides specifications forthe image, audio, subtitle (Timed Text and subpictures) Digital Cinema DistributionMasters. The DCDM-Image defines a common set of image structures for DigitalCinema by specifying an image containers and colorimetry for a Digital CinemaDistribution Master (DCDM). The DCDM-Audio specifies the following characteristics: bitdepth, sample rate, minimum channel count, channel mapping and reference levels. TheDCDM-subtitles specifies the format of a Digital Cinema subtitle track file. A subtitle trackfile contains a set of instructions for placing rendered text or graphical overlays atprecise locations on distinct groups of motion picture frames. A subtitle track file is anintegral component of a Digital Cinema composition and may be present in bothmastering and distribution file sets.• Compression (Image): Specifies the DCI compliant JPEG 2000 codestream and JPEG2000 decoder.• Packaging: This section defines the requirements for packaging the DCDM (image,audio and subtitle) files using (where possible) existing Material eXchange Format(MXF) specifications and eXtensible Mark up Language (XML). The output of thisprocess is the Digital Cinema Package (DCP). This section also defines the1 Metro-Goldwyn-Mayer withdrew as a Member of DCI in May 2005, prior to the completion of this SpecificationDCI Digital Cinema System Specification v.1.2 Page 15