 |  | What is Digital Cinema?
Digital cinema refers to the use of digital technology to distribute and project motion pictures. A movie can be distributed via hard drives, optical disks or satellite and projected using a digital projector instead of a conventional film projector. Digital cinema is distinct from high-definition television and in particular, is not dependent on using television or HDTV standards, aspect ratios, or frame rates. Digital projectors capable of 2K resolution began
deploying in 2005, and since 2006, the pace has accelerated. (2K refers to images with 2048 horizontal pixel resolution.)
Technology
To match or improve the theater experience of movie audiences, a digital cinema system must provide high-quality image and sound. Additionally, theater managers require server controls for managing and displaying content in multiple theaters, and studios want their content encrypted with secure delivery, playback, and reporting of play times to the distribution company.
Digital Cinema Initiatives (DCI), a joint venture of the six major studios, published a system specification for digital cinema. Briefly, the specification calls for picture encoding using the ISO/IEC 15444-1 "JPEG2000" (.jp2) standard and use of the CIE XYZ color space at 12 bits per component encoded with a 2.6 gamma applied at projection, and audio using the "Broadcast Wave" (.wav) format at 24 bits and 48 kHz or 96 kHz sampling, controlled by an XML-format Composition Playlist, into an MXF-compliant file at a maximum data rate of 250 Mbit/s. Details about encryption, key management, and logging are all discussed in the specification as are the minimum specifications for the projectors employed including the color gamut, the contrast ratio and the brightness of the image. While much of the specification codifies work that had already been ongoing in the Society of Motion Picture and Television Engineers (SMPTE), the specification is important in establishing a content owner framework for the distribution and security of first-release motion picture content.
Digital cinema conforming to the DCI Standard is referred to within the film industry as D-Cinema while all other forms of digital cinema are referred to as E-Cinema. Thus, while D-Cinema is a defined standard, though one that is still partly being framed by SMPTE as of 2007, E-Cinema may be anything, ranging from a DVD player connected to a consumer projector to something that approaches the quality of D-Cinema without conforming to some of the standards. Even D-Cinema itself has evolved over time before the DCI standards were framed. However, the current DCI standards were made with the intention of standing the test of time, much like 35 mm film which has evolved but still retained compatibility over a substantial part of a century.
In addition to DCI's work, the National Association of Theatre Owners (NATO) released its Digital Cinema System Requirements. The document addresses the requirements of digital cinema systems from the operational needs of the exhibitor, focusing on areas not addressed by DCI, including access for the visually impaired and hearing impaired, workflow inside the cinema, and equipment interoperability. In particular, NATO's document details requirements for the Theatre Management System (TMS), the governing software for digital cinema systems within a theatre complex, and provides direction for the development of security key management systems. As with DCI's document, NATO's document is also important to the SMPTE standards effort.
Digital capture
As of 2009 the most common acquisition medium for digitally projected features is 35 mm film scanned and processed at 2K (2048×1080) or 4K (4096×2160) resolution via digital intermediate. Most digital features to date have been shot at 1920x1080 HD resolution using cameras such as the Sony CineAlta, Panavision Genesis or Thomson Viper. New cameras such as the Arriflex D-21 can capture 2K resolution images, and the Red Digital Cinema Camera Company's Red One can record 4K redcode *RAW. The marketshare of 2K projection in digital cinemas is over 98%. Currently in development are other cameras capable of recording 4K RAW, such as Dalsa Corporation's Origin, and cameras capable of recording 5K *RAW, such as the RED EPIC, and cameras capable of recording 3K *RAW (for budget filmmakers) such as the RED SCARLET.
(Raw redcode is a proprietary wavelet compression scheme offered on the redone camera. It can be defined further on user sites such at reduser, but is not by definition RAW, and does potentially contain compression artifacts.)
Digital post-production
In the post-production process, camera-original film negatives (the film that physically ran through the camera) are scanned into a digital format on a scanner or high-resolution telecine. Data from digital motion picture cameras may be converted to a convenient image file format for work in a facility. All of the files are 'conformed' to match an edit list created by the film editor, and are then color corrected under the direction of the film's staff. The end result of
post-production is a digital intermediate used to record the motion picture to film and/or for the digital cinema release.
Digital mastering
When all of the sound, picture, and data elements of a production have been completed, they may be assembled into a Digital Cinema Distribution Master (DCDM) which contains all of the digital material needed for projection. The images and sound are then compressed, encrypted, and packaged to form the Digital Cinema Package (DCP).
Digital projection
There are currently two types of projectors for digital cinema. Early DLP projectors, which were deployed primarily in the U.S., used limited 1280×1024 resolution or the equivalent of 1.3 MP (megapixels). They are still widely used for pre-show advertising but not usually for feature presentations. The DCI specification for digital projectors calls for two levels of playback to be supported: 2K (2048×1080) or 2.2 MP at 24 or 48 frames per second, and 4K (4096×2160) or 8.85 MP at 24 frames per second.
Three manufacturers have licensed the DLP Cinema technology developed by Texas Instruments (TI): Christie Digital Systems, Barco, and NEC. Christie, long established in traditional film projector technology, is the maker of the CP2000 line of projectors—the most widely deployed platform globally (approximately 5,500 units in total). Barco launched the DP-series of 2K DCI-compliant Digital cinema projectors; next to this Barco designs and develops visualization products for a variety of selected professional markets. NEC manufactures the Starus NC2500S, NC1500C and NC800C 2K projectors for large, medium and small screen respectively and the Starus Digital Cinema Server system, as well as other equipment to connect PCs, analog/digital tape decks and satellite
receivers, DVD, and off-air broadcast, etc. for pre-show and special presentations. While NEC is a relative newcomer to Digital Cinema, Christie is the main player in the U.S. and Barco takes the lead in Europe and Asia. In addition Digital Projection Incorporated (DPI) designed and sold a few DLP Cinema units when TI's 2K technology first debuted but then abandoned the D-Cinema market while continuing to offer DLP-based projectors for non-cinema purposes. Although based on the same 2K TI "light engine" as those of the major players they are so rare
as to be virtually unknown in the industry. As of January, 2009, there are more than 6,000 DLP-based Digital Cinema systems installed worldwide, of which 80% are located in North America.
The other technology is made by Sony and is labeled "SXRD" technology. The projectors, the SRXR210 and SRXR220, offer 4096x2160 (4K) resolution and produce four times the number of pixels of 2K projection, yet Sony's systems are priced competitively with the lower resolution 2048x1080 (2K) or 2.2 MP (megapixels) DLP projectors.
Other manufacturers have been developing digital projector technology, but these have not yet been deployed into cinemas and are not commercially available in versions that conform to the DCI specification.
Economics
Savings in distribution
Digital distribution of movies has the potential to save money for film distributors. A single film print can cost around US$1200 (or $30,000 for a 1-time print of an 80-minute feature), so making 4,000 prints for a wide-release movie might cost $5 million. In contrast, at the maximum 250 megabit-per-second data rate (as defined by DCI for digital
cinema), a typical feature-length movie could fit comfortably on an off the shelf 300 GB hard drive—which sell for as little as $40 (retail price, volume prices are even lower) and can even be returned to the distributor for reuse after a movie's run. With several hundred movies distributed every year, industry savings could potentially reach $1 billion or more.
Alternative content
An added incentive for exhibitors is the ability to show alternative content such as live special events, sports, pre-show advertising and other digital or video content. Some low-budget films that would normally not have a theatrical release because of distribution costs might be shown in smaller engagements than the typical large release studio pictures. The cost of duplicating a digital "print" is very low, so adding more theaters to a release has a small additional cost to the distributor. Movies that start with a small release could scale to a much larger release quickly if they were sufficiently successful, opening up the possibility that smaller movies could achieve box office success previously out of their reach. Alternate content is also finding a market in third world countries in which the higher costs and quality of DCI equipment are not yet affordable.
Greater protection for content
A last incentive for copyright holders for digital distribution is the possibility of greater protection against piracy. With traditional film prints, distributors typically stagger the film's release in various markets, shipping the film prints around the globe. In the subsequent markets, pirated copies of a film (i.e. a cam) may be available before the movie is released in that market. A simultaneous worldwide release would mitigate this problem to some degree.
Simultaneous worldwide releases on film have been used on The Da Vinci Code, Lord of the Rings: Return of the King, Star Wars: Revenge of the Sith, Charlie's Angels: Full Throttle and Mission: Impossible III amongst others. With digital distribution, a simultaneous worldwide release would not cost significantly more than a staggered release.
Costs
On the downside, the initial costs for converting theaters to digital are high: up to $150,000 per screen or more. Theaters have been reluctant to switch without a cost-sharing arrangement with film distributors. Recent negotiations have involved the development of a Virtual Print License fee which the studios will pay for their products which allows financiers and system developers to pay for deployment of digital systems to the theaters,
thus providing investors a certain payback.
While a theater can purchase a film projector for US$50,000 and expect an average life of 30–40 years, a digital cinema playback system including server/media block/and projector can cost 3–4 times as much, and is at higher risk for component failures and technological obsolescence. Experience with computer-based media systems show that average economic lifetimes are only on the order of 5 years with some units lasting until about 10 years before they are replaced.
Archiving digital material is also turning out to be both tricky and costly. In a 2007 study, the Academy of Motion Picture Arts and Sciences found the cost of storing 4K digital masters to be "enormously higher - 1100% higher - than the cost of storing film masters." Furthermore, digital archiving faces challenges due to the insufficient temporal qualities of today's digital storage: no current media, be it optical discs, magnetic hard drives or digital tape, can reliably store a film for a hundred years, something that properly stored and handled film can do.
History
Digital media playback of hi-resolution 2K files has at least a twenty year history with early RAIDs feeding custom frame buffer systems with large memories. Content was usually restricted to several minutes of material.
Transfer of content between remote locations was slow and had limited capacity. It wasn't until the late 1990s that feature length projects could be sent over the 'wire' (Internet or dedicated fiber links).
There were many prototype systems developed that claim a first in some form of digital presentation. However, few of these had a significant impact on the advance of the industry. Key highlights in the development of digital cinema would likely include: demonstrations by TI of their DMD technology, real-time playback of compressed hi-resolution files by various vendors, and early HD presentations from D5 tape to digital projectors.
Standards development
The Society of Motion Picture and Television Engineers began work on standards for digital cinema in 2001. It was clear by that point in time that HDTV did not provide a sufficient technological basis for the foundation of digital cinema playback. (In Europe and Japan however, there is still a significant presence of HDTV for theatrical presentations. Agreements within the ISO standards body have led to these systems being referred to as Electronic Cinema Systems (E-Cinema).)
Digital Cinema Initiatives (DCI) was formed in March 2002 as a joint project of many motion picture studios (Disney, Fox, MGM, Paramount, Sony Pictures Entertainment, Universal and Warner Bros. Studios) to develop a system specification for digital cinema. In cooperation with the American Society of Cinematographers, DCI created standard evaluation material (the ASC/DCI StEM material) and developed tests of 2K and 4K playback and compression technologies. DCI published their specification in 2005.
Stereo 3-D images
In late 2005, interest in digital 3-D stereoscopic projection has led to a new willingness on the part of theaters to co-operate in installing a limited number of 2K stereo installations to show Disney's Chicken Little in 3-D film. Six more digital 3-D movies were released in 2006 and 2007 (including Beowulf, Monster House and Meet the Robinsons). The technology combines two digital projectors fitted with polarizing filters with the use of polarized glasses and silver screens. A single projector can also be used in conjunction with a simple adapter in the front (a single-cell LCD screen that acts as a quarter-wave retarder, also known as a zscreen) that rotates the polarity of projector's light output several times per second to alternate quickly the left-and-right-eye views. Another system from Dolby Laboratories called Dolby 3D makes use of a special color filter and glasses and has the advantage that doesn't require a silver screen. Also, some theaters use a system that requires no modification on the screen or the projector but uses active liquid crystal shutter glasses that quickly block the views of each eye alternatively.
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