Contents |
Technology
To match or improve the theater experience of movie audiences, a digital cinema system must provide high quality image, sound, subtitles, and captions. 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.
In this article, 2K and 4K refer to images with 2048 and 4096 horizontal pixel resolution, respectively.
The Digital Cinema Initiatives (DCI), working in conjunction with members of the SMPTE standards commitee, has published a system specification for digital cinema that was agreed upon by the major studios. A draft of this specificaton can be found at (dcimovies.com pdf file). 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 1/2.6 gamma, 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 Mbits/sec. Details about encryption, key management, and logging are all discussed in the specification.
Digital capture
- See also: digital cinematography
Digital post-production
Film is scanned from camera-original film negatives into a digital format, typically Cineon (pdf) -format or SMPTE DPX files, 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 (DI). This D.I. may be used to record the motion picture to film, or as the basis for the digital cinema release. As of 2005, the Digital Intermediate route of scanning the entire film, (not just effects sequences) and then recording back to a film internegative is becoming the dominant method for finishing a film. It may shortly become the standard route for even low to medium budget features, and features that originate on Super 16mm film.
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 a show. The images and sound are then compressed, encrypted, and packaged to form the Digital Cinema Package (DCP).
Digital Cinema Distribution
The DCP is transmitted to theater servers via different methods that may includ: hard drives, LTO tapes, DVDs, or satellite.
Physical Media Distribution
Digital content is currently distributed on hard drive for feature content and DVD for trailer content. Other potential physical media include LTO3 tape or high-capacity DVD's.
Network Delivery
Digital files can be delivered to theater servers via shared or dedicated network connections.
Satellite Delivery
Content can be sent in a multi-cast transmission to theatres via satellite. The received files have to be verified and missing or corrupted portions would have to be rebroadcast.
Distribution Challenges
Each method of distribution faces it's own unique challenges and there is currently much debate regarding preferred methods. The issue can become hotly debated by advocates for the various methods and media. Currently, there is no industry or de-facto standard for distribution. This issue will likely be decided by market forces and business models. There is some testing of the various methods going on that may provide empirical data and objective analysis in the future.
Digital Cinema Distributors
Technicolor, Deluxe and Access Integrated Technologies are the leading companies in distribution and have signed digital distribution agreements with the majority of Hollywood studios. Other companies currently distributing digital cinema include Kodak and Dolby.
Of the digital distributors, Technicolor and Deluxe currently distribute film, as well.
Digital projection
There are currrently two types of projectors for digital cinema. The original one in the US was DLP technology. Early DLP projectors used limited 1280 x 1024 resolution which are still widely used for pre-show advertising but not usually for feature presentations. The current specification for digital projectors calls for three levels of playback to be supported: 2K (2048x1080) at 24 frames per second, 4K (4096x2160) at 24 frames per second, and 2K at 48 frames per second. Three manufacturers have licensed the TI-developed DLP technology. Christie Digital Systems, makers of the CP2000, a 2K DCI compliant Digital Cinema Projector, and Barco are the market leader in terms of units sold and deployed internationally. Where Christie is the main player in the USA, Barco takes the lead in Europe and Asia, resulting in an equal share world-wide.
The other soon to be deployed technology is from Sony and is labeled "SXRD" technology. Their projector provides 4096x2160 resolution.
Other manufacturers have been developing digital projector technology, but these have not yet been deployed into motion picture theaters.
Current Developments
In mid 2006, about 400 theaters have been equipped with 2K digital projectors with the number increasing every month.
Chicken Little from Disney, with its experimental release of the film in digital 3D, increased the number of projectors using the 2K format. Several digital 3D films will surface in 2006 and several prominent filmmakers have committed to making their next productions in stereo 3D.
By early 2006, Access Integrated Technologies (AccessIT) had announced agreements with nearly all of the major Hollywood studios and several exhibitors that enable the company to roll-out its end-to-end digital cinema systems.
Economics
Digital cinema has some big economic advantages over film. Digital video is very cheap compared to film. For instance Rick McCallum, a producer on Star Wars Episode II: Attack of the Clones, said that it cost US$16,000 for 220 hours of digital tape where a comparable amount of film would have cost US$1.8 million. Obviously this matters most to low-budget films which are often shot for a few million dollars or less.
Digital cinema can also reduce costs while shooting and editing. It is possible to see the video and make any necessary adustments immediately instead of having to wait until after the film is processed. Digital footage can also be edited directly, whereas with film it is usually converted to digital for editing and then re-converted to film for projection.
Digital distribution of movies also has the potential to save money for film distributors. A single film print can cost around US$1200, so making 4000 prints for a wide-release movie might cost $5 million. With several hundred movies distributed every year, industry savings could potentially reach $1 Billion or more.
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 engagments 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.
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 financers and system developers to pay for deployment of digital systems to the theaters, thus providing investors a certain payback.
History
The Society of Motion Picture and Television Engineers began work on standards for digital cinema in 2001.
Digital Cinema Initiatives (DCI) was formed in March 2002 as a joint project of the 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.
Several feature films were shown in 1999 using DLP prototype projectors and early wavelet based servers. For example, Walt Disney Pictures "Bicentennial Man" was presented using a QuBit server manufactured by QuVis of Topeka Kansas. DVD ROM was used to store the compressed data file. The DVD ROMs were loaded into the QuBit server hard drives for playout. The file size for "Bicentennial Man" was 42GB with an average data rate of 43 Mbits/sec.
In 2000, Walt Disney, Texas Instruments and Technicolor with the cooperation of several US and international exhibitors, began to deploy prototype Digital Cinema systems in commercial theatres. The systems were assembled and installed by Technicolor using the TI mark V prototype projector, a special Christie Inc lamp housing, and the QuBit server with custom designed automation interfaces.
Technicolor manufactured the DVDs for uploading on these test systems and was responsible for sending technicians out to the locations for every new feature film that was played. The technicians would typically spend ten or so hours to load the files from the DVD to the QuBit, set up the server to play the files, and then set up the projector. A full rehearsal screening of the feature was mandatory as was the requirement to have back up DVDs and backup QuBits available should something fail.
The systems were eventually replaced or upgraded after TI made improvements to the projectors and Technicolor developed a purpose built digital cinema server in a venture with QUALCOMM, the engineering giant from San Diego best known for advanced mobile phone technology. The new systems were called AMS for "Auditorium Management Systems" and were the first digital cinema servers designed to be user friendly and operate reliably in a computer hostile environment such as a projection booth. Most importantly they provided a complete solution for content security.
The AMS used removable hard disk drives as the transport mechanism for the files. This eliminated the time required to upload the DVD ROMs to the local hard drives and provided the ability to switch programs quickly. For security, the AMS used a media block type system that placed a sealed electronics package within the projector housing. The server output only 3DES encrypted data and the media block did the decryption at the point just before playout.
The first secure encrypted digital cinema feature was Star Wars Episode II: Attack of the Clones.
The system functioned well but was eventually replaced because of the need to create a standard data package for D-cinema distribution.
Stereo 3D images
In late 2005, interest in digital 3D 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 3D. Seven more digital 3D movies are slated for 2006 or 2007 release. The technology combines digital projectors with the use of polarized glasses and screens. DLP technology is well -suited for stereo 3D as it can handle the higher frame rates required for flicker free presentations.
Digital cinema companies
Access Integrated Technologies, Inc. (AccessIT)
Avica Europe
Barco: digital projectors
Christie: digital projectors
Dalsa
Digitale Videosysteme
Dolby Laboratories
Doremi Laboratories, Inc.
EFilm
FilmLight
Kodak
Lucasfilm
NEC Solutions America: DLP Cinema projectors and DCI compliant servers
QuVIS: Quality Visual Information Systems-providing DCI compliant servers
Real Image Media Technologies
Rising Sun Research
Sony
Technicolor
Texas Instruments
XDCinema: digital media management
See also
External links
- How Digital Cinema Works
- Digital Cinema: A Slow Revolution
- Megapixel calculator for 2K/4K Digital Cinema
- Digital Cinema Laboratory at USC — an industry-supported test bed for establishing benchmarks and standards in digital cinema
- CNN story on Star Wars Episode II
- Comparison of 16 mm to digital
- HD at Sundance
- DCinemaToday.com - Industry news and database