DCI Specs - Digital Cinema Initiatives

9.4.3.3. Show PlaybackShow playback processes include auditorium preparations for the playback of a specificShow Playlist, and the actual run-time security functions that include content decryptionat the Media Decryptor(s), link encryption/decryption, forensic marking, and recording oflog data.• Equipment suite preparations – The SM shall prepare the suite forplayback prior to each composition showing. This shall include validation ofthe authenticity and "trust status" of the suite SPBs, and delivery of allnecessary keys per Section 9.4.3.5 Functions of the Security Manager (SM).SMs shall obtain trust status by confirming that the SPBs are listed in the TDLdelivered as part of each KDM required for the entire Show Playlist. Differentcompositions may have different requirements and the system shall checkthe SPBs against the TDL for each composition independently.Informative note: In the case of a fully integrated auditorium suite architecture(i.e., Auditorium 1 of Figure 15: Digital Cinema Auditorium SecurityImplementations), there are no remote SPBs and the KDM's TDL may beempty.• Streaming media decryption – Playback of a show consists of aconcatenation of compositions that require serial or (separately) paralleldecryption. One or more Media Decryptors (e.g., for image, audio or subtitle)may be involved.• Link Encryption (LE) and Link Decryption (LD) – If Link Encryption isused, the SM shall support keying of LE and LD Security Entities.• Forensic Marking – Each MB shall apply Forensic Marking to image andaudio data during playback.• Log data recording – The SEs shall capture and transfer log records ofplayback events to the Image Media Block (IMB) SMs as specified in Section9.4.6.3 Logging Subsystem.The flow chart in Figure 18: Show Playback Overview, is an example of how a systemmay execute a Show Playlist. This flow chart is informative. There are other designs thatmay have different steps or different sequences that will accomplish the same result andmeet the requirements of this specification.DCI Digital Cinema System Specification v.1.2 Page 107