Digital Cinema in 2010 - a Mid-Year Report
by Michael Karagosian
©2010 MKPE Consulting LLC All rights reserved worldwide
Digital cinema sales were moving at full speed as 2010 began. The pace was set in 2009 in anticipation of the 3D release of Avatar in late December. A doubling of digital projector installations took place, resulting in more than 16,000 digital cinema systems installed worldwide, half of which were 3D capable. Nearly all of the growth was in 3D capable screens. The chart in Fig. 1, courtesy of Screen Digest, illustrates the growth in digital screens by region.
Even as Avatar's box office began to decline, 3D continued to drive the conversion of cinemas to digital projection. The box office success of Avatar, and a pipeline of 3D releases, including blockbusters Alice and How to Train Your Dragon, led to more growth in sales. By end of the first half of 2010, the U.S. reached the 10,000 digital screen milestone. Continuing with the trend, nearly 50% of these are 3D capable. (see Fig. 2.)
In March of 2010, U.S. deployment entity Digital Cinema Implementation Partners (DCIP) announced the completion of $660 million in funding for the purchase of digital projection systems. DCIP is a joint venture of major cinema chains AMC, Cinemark, and Regal Entertainment. The financing will enable the digital conversion of approximately 10,000 of the collective 16,000 screens operated by these circuits. Conversion of the 10,000 screens is expected to complete by 2012.
Other milestones include the release-to-market of the Series 2 generation of Texas Instruments DLP Cinema projectors. With the introduction of Series 2, licensees Barco, Christie Digital, and NEC were able to proclaim DCI-compliant products by mid-year, the first time ever that any manufacturer's product had passed the DCI Compliance Test Plan.
The DCI specification is the cornerstone of digital cinema. It represents the intent of the six major studios to use common methods for the distribution of content and for maintaining the security of that content. DCI Compliance is mandated in equipment financing deals, and manufacturers actively strive to meet the specification.
However, a cloud was cast over the DCI specification in January by the U.S. National Institute of Standards and Technology (NIST). NIST is the organization responsible for the FIPS 140-x series of security standards, developed for “the utilization and management of computer and related telecommunications systems in the Federal government.” As a core tenement of its security specification, DCI calls for compliance to FIPS 140-2. It has been known for several years that NIST planned to transition to a revised FIPS 140-3 specification. But the impact on the industry was not clear until the past year, when NIST incorporated changes to FIPS 140-2 through a revision of the standard's Annex A and through circulation of transition document NIST SP800-131.
With the new changes by NIST, the DCI specification was challenged in three areas:
(1) SHA-1 Hash is no longer allowed for digital signatures, called for by both the DCI specification and SMPTE standards.
(2) The method described in ANSI 9.31 cannot be used as a random number generator for generating content keys, as called for by DCI.
(3) The key pair used for a digital signature cannot be used for other purposes. DCI requires the re-use of the media block key pair for AES key encryption in the KDM, for establishing TLS sessions, in addition to signing security logs.
In response to comments, NIST relaxed its call for a year-end transition for items (1) and (2), introducing a deprecation period of three and five years, respectively, for use of these algorithms. Among the many entities that requested extensions was the U.S. Department of Defense. However, only DCI requested to extend the time allowed for multi-use of the media block key pair, which unfortunately did not sway NIST. Unless NIST changes its mind by year end, multi-use use of the media block key pair will no longer be allowed after December 31, 2010, in FIPS 140-2-compliant equipment. Media blocks will be required to be redesigned to carry more than one digital certificate.
The new NIST rule raises a number of issues. Clearly, the changes imposed by NIST are outside of DCI's control. If no action is taken, the DCI specification will be in conflict with itself after December 31, rendering insignificant a document that is core to digital cinema. Among its options, DCI can render obsolete current equipment and continue to require FIPS approval, relax its requirement for FIPS approval of equipment, or develop its own security specification that maintains the status quo in equipment design and is supported by a formal testing process.
Perhaps more pertinent is that an industry still in its infancy is unprepared to address obsolescence. Perhaps 20,000 screens have been converted out of a worldwide footprint of 150,000. Any move toward obsolescence today could trigger severe repercussions. But change is inevitable. NIST's actions were not capricious, but calculated to maintain an effective security standard in the face of advancing computational power. Even if DCI were to part ways with NIST, it would still be faced with the eventual upgrade of its security specification.
In the area of the more mundane day-to-day aspects of digital cinema, the industry continues to suffer operational problems with security key management. The DCI specification does not call for an effective means to manage security keys across a worldwide footprint of installations. SMPTE standardized the Facility List Message (FLM) for this purpose, but without a specification to require its use, there has been little or no implementation of it in the field. Studios and their vendors scramble to provide such management through whatever means available, including direct phone calls to each site. Still, some shows are lost due to the movement of equipment, poor management of security key information, or delay in getting the right keys to the right equipment. Ironically, the fast adoption of digital 3D projection, in which only a few screens per complex are often converted, has contributed to the magnitude of the problem.
In a world of sophisticated network-based communications, the primary means of delivery for Key Delivery Messages (KDMs) remains personal e-mail. Although this is an improvement over early snail-mailing of USB memory sticks, it is not an elegant solution. In an encouraging move, Mike Radford of Fox presented an open RESTful approach to FLM management to the Inter-Society Digital Cinema Forum (ISDCF). More work is needed, however, if open, automated communication of KDMs are to take place. The diagram in Fig. 3 illustrates the distribution workflow challenge in digital cinema.
After 11 years of developing standards, the industry is now beginning to incorporate them. Of primary value is the transition to “SMPTE DCP,” the standardized distribution package. To aid in this effort, the ISDCF is conducting demonstrations and “plugfests” to bring manufacturers and fulfillment entities together to test their wares. Its efforts have been hugely successful, uncovering problems that otherwise would only be discovered in production. At least three such plugfests are planned for 2010, and possibly more in 2011, if necessary, to bring confidence to users.
The ISDCF effort has also been of tremendous value in testing accessibility systems. Accessibility continues to be a major focus across the industry, and SMPTE has played a significant role. In 2008, SMPTE standardized the distribution of closed captions with S428-10 DCDM Closed Caption and Closed Subtitle and S429-12 Caption and Closed Subtitle. In 2009, SMPTE successfully balloted S430-10 Aux Content Synchronization Protocol and S430-11 Aux Resource Presentation List, together describing an open protocol that enables third-party closed caption systems to connect to compliant digital cinema servers. In addition, S429-2 DCP Operational Constraints, published in 2009, identifies how hearing impaired (HI) and visually impaired narrative (VI-N) audio channels may be carried in compliant audio distributions. The support for accessibility in distribution and equipment standards is a first for the motion picture industry, eliminating the proprietary distributions and protocols found in film systems and encouraging much needed competition in accessible products.
But, as sometimes happens, there were surprises. The publication of 430-11, a key document in the server-to-system communication of closed captions, ran into a snag in early 2010. An error in S433 XML Data Types was found that affects several existing standards, including the then about-to-be-published S430-11. S433 normatively defines the DCML namespace name with a terminating “/”. However, the original informative schema distributed with the S433 document did not use the terminating “/” in its DCML namespace name. Developers that based their designs only on the S433 informative schema file found themselves in a pickle. In June 2010, the 21DC Technology Committee decided to stay the course and maintain the normative prescription for the DCML namespace name. The direction requires changes to several standards to amend their use of DCML, including S430-11. Manufacturers whose products incorporate the S433 DCML schema must be sure to use the normative DCML namespace name prescribed in S433.
Altogether, 2010 promises to be a watershed year for digital cinema. With the rollout of technology moving at a fast pace, the incorporation of SMPTE standards in products moving forward, the coming-to-market of the advancements in accessibility, and the challenges to be met by DCI, this will be a year to be remembered.