SMPTE 21DC held its quarterly Ad Hoc Group and Study Group day of meetings, where the majority of the work of the technology committee actually takes place. The quarterly meeting of parent 21DC Technology Committee for Digital Cinema will take place later in Geneva mid-September. TC meetings have become more of a plenary session than a working session, reporting on work activities and conducting formal ballots when needed.
Four working sessions were held, the first of which was that of the Stereo Subtitling Ad Hoc Group. This group has been meeting for approximately two years, with what originally appeared as a straight-forward task. 3-D subtitling tests were independently conducted, studying the several ways in which 3-D text can be expressed, and examining appropriate text decoration methods. Simultaneously, public ISDCF Plugfest testing of 2-D subtitling took place. The Plugfest work revealed that the core 2-D subtitling standard was in need of improvement, independent of those changes planned for 3-D. In addition, consideration needed to be given to downstream methods for labeling 3-D text in consumer applications. Fortunately, all of this work has now completed, and the group will soon recommend for ballot the necessary changes to existing documents for the implementation of 3-D subtitling.
The Higher Frames Rates Study Group is publishing a summary of its Interim Report in the forthcoming issue of the SMPTE Journal. The next step for this group is compression bit rate testing, which requires funding and a lot of behind-the-scenes work to accomplish.
The Audio Ad Hoc Group has completed its work of producing new standards for individual audio channel labeling. Even so, chairperson Brian Vessa took the opportunity to hold a meeting and gather the troops for a thought provoking session on higher channel counts. Brian floated a strawman document for discussion the evening prior, capturing a concept for creating a speaker layout that would encompass multiple high-channel-count sound formats. Studios might install the entire array, while exhibitors might only install those speakers that apply to the particular sound system deployed in the auditorium. It’s an interesting concept that may lead to a new study effort.
The fourth meeting was a presentation by David Reisner and Michael Wilsker of their work-in-progress for an Engineering Guideline documenting the functionality of the digital cinema package. Eleven years after the first concept document for digital cinema packaging was drafted, it’s good to see formal educational material on the subject entered the SMPTE body of work.
The next meeting of the 21DC Technology Committee will be held on September 15 in Geneva. On the table will be two projects proposed by Dolby Laboratories: one for the synchronization of processors external to the media block, and another for defining an auxiliary track file capable of carrying just about any type of essence. The projects are proposed by Dave Schnuelle, who as the former chair of 21DC, instituted a rule that no new standards work should be undertaken until two companies were behind it, and working interoperable prototypes had been developed. Dave may have forgotten his own rule. More to the point, there are numerous factors to be considered when synchronizing external processors. How does the media block know that the external processor is present and working? How does the external processor receive the appropriate track file? If the track file is encrypted, how does it get decrypted? Is watermarking needed in the external processor? It is a subject worthy of study, but would seem to be premature for standards. It should prove to be an interesting meeting.