DCI Specs - Digital Cinema Initiatives

Block may use a push or pull method to process essence data from storage, as shown inFigure 12.Figure 12: Media Block in Projector Configuration 8Note: Due to the dynamic nature of security technology, DCI reserves the right, at somefuture time, to update requirements and may require changes to Digital Cinema systemsas situations warrant.7.5.4.2. Media Block Functional Requirements7.5.4.2.1. SynchronizationThe Media Block is the device that converts, in real time, the packaged content datafrom storage into data for playback to downstream devices. The Media Block isrequired to playback the image, audio and other timed dependant content in amanner that presents a synchronized performance to the audience.7.5.4.2.2. Security FunctionsThe main function of the Media Block is to provide a secure environment withinwhich to perform content essence decryption. In support of this, the Media Blockshall contain the Security Manager, image, audio and subtitle processing and theassociated forensic markers. Link Encryption shall be applied to image essence if theMedia Block is not contained within the projection system.All Media Blocks are required to provide logging functions per the requirements ofSection 9.4.6.3.1 Logging Requirements..7.5.4.2.3. Image Link Encryption and Decryptor BlockIf the Image Media Block is not physically located in the same secure container asthe projector, then the Image Media Block is required to provide link encryption to theprojection system to protect image essence per Section 9.4.4 Link Encryption. At theprojector, a Link Decryptor Block is required to decrypt the image essence. The LinkDecryptor Block is required to provide SPB type 1 physical protection for linkdecryption, the associated security keys and logging functions.DCI Digital Cinema System Specification v.1.2 Page 71