DCI made two announcements this month. The first regarding the approval of a new in-projector media block from Digicine Oristar Technology Development of Beijing (not to be confused with Digicine of USA, which hosts the Interop DCP specification, and assumed the assets of server company Avica). The second is a new Architectural Description for the application of multiple media blocks, in response to the introduction of multiple media blocks by Dolby with Atmos.
The Digicine Oristar announcement is uniquely interesting as its media block was approved with the Sony SRX-R515 projector. This is the first time a manufacturer other than Sony submitted a media block for one of its projectors. It seems unusual to submit a new media block at the end of the massive digital cinema sales bubble. But the manufacturer is in China, where significant growth in new cinemas is taking place. It would appear that Sony is interested in a partnership with Digicine Oristar to develop sales of its projectors in China. Presumably Digicine is predicting sufficient sales of the Sony projector to warrant its investment in a new media block.
The release by DCI of its new Digital Cinema Multiple Media Block (MMB) Architectural Description was strongly hinted by DCI when instructing its testing centers with new rules for KDM management in the presence of multiple media blocks. The Architectural Description is needed to clarify the confusing situation created by studios when first suggesting that Dolby manage KDMs in a certain manner with Atmos outboard audio processing, and then reversing itself through amendments given to DCI Compliance testing centers with conflicting instructions. It probably raises a few issues, however, just as it resolves outstanding issues.
Certainly for Dolby, it must instigate a headache, as the company will have to update several hundred processors in the field to comply with the new guideline, which specifies that each media block now requires a unique KDM. One can ponder that if the delivery of one KDM to an auditorium has proven difficult to manage efficiently, how much less efficient will this new rule be? The guideline also specifies a high degree of synchronization, in addition, that puts in place a high bar for manufacturers. Statements such as “The synchronization signal…must be accurate within 10 microseconds” sound great, but how does one measure a synchronization signal? We’re normally more concerned about the performance that takes place in the auditorium. For this, the specification merely states “Synchronization of audio and on-screen text to image shall be frame-accurate.” Is this last spec really good enough?
Most interesting is the manner in which forensic marking is to be handled when multiple media blocks are used to process image with multiple projectors. The challenge with such arrangements is for each projector to display the same identifier, for easy identification of the auditorium from where content is stolen. In current designs, the forensic mark identifier is buried in the silicon of the media block. DCI will soon change this by introducing a new forensic mark keytype to identify an encrypted seed in the KDM for determination of the FM identifier in the media block.
Presumably, the new specification is clear enough to simply updates to the DCI Test Plan, allowing individual approval of media blocks designed to operate on only one type of essence, such as object-based audio.