1 Security in digital cinema Touradj Ebrahimi Business of Cinema 2 Traditional: The business of cinema is the exhibition of film based theatrical content to audiences for their enjoyment 1
Cinema Overview 3 Film based media 100 year old technology Well understood media Well understood work flow Equipment is relatively inexpensive Numerous vendors High interoperability Highly Standardized What is wrong with film? 4 Cost Each and every print has a cost associated with it Every screen needs a print Quality Film prints can vary in quality levels Lifespan Film prints fade and become scratched over a short period of time 2
Why go digital cinema? 5 Distribution costs are lower A print is a file on a hard drive Film making is steadily moving towards an all electronic process Many films are mastered digitally Digital Intermediates are common Ability to show alternative content with the same projection system Live content is now available Digital Cinema Attributes 6 Great picture and sound No jitter and weave Image doesn t fade No dirt or scratches One copy can be shown on many screens Allows scheduling flexibility Delivery costs are shared within a multiplex Has the word Digital in the name! 3
The case for Digital Cinema 7 Financial Print costs vary from $650 to $1200 Electronic distribution will be much less Release inventory can be reduced to a single package containing multiple languages, subtitles, and censorship edits Quality Image quality can rival Prints Images will maintain quality indefinitely Digital Cinema Glossary 8 Digital Cinema (D-Cinema) Electronic distribution and exhibition of high quality theatrical releases Digital form of the traditional business Electronic Cinema (E-Cinema) Electronic distribution and exhibition of non -theatrical entertainment Alternative content Sporting events, Concerts, Stage 4
End-to-end System 9 Production Content is created Distribution Finished content is delivered to the exhibitor Exhibition Content is presented to the audience Traditional Process Flow 10 Film is key Storage and delivery media Delivery is by physical means Most problems are related to film itself 5
Digital Process Flow 11 Content is stored on hard drives At the distributor and at the theater Distribution can be physical media or via telecommunication network Physical example - Disc or tape Network example - Satellite or fiber Electronic or Film? 12 Digital technology is already here The lines are blurred at every step 6
Film Flow - Imagery 13 Film Flow - Sound 14 7
Putting it together 15 Original Negative Duplication 16 Answer Print Check Print Original Negative Inter Positive Inter Negative Release Print 8
Duplication Quality 17 Original Negative Inter Positive Inter Negative Release Print D-Cinema 18 Elements will be separate throughout the mastering and distribution chain Audio, imagery, and data will be combined at the theater Final show will be dependant on language and culture In short, final editing will be done at the theater based on edit lists delivered with the release package Imagery will contain both 2k and 4k data Comparable to shipping 35 mm and 65 mm together Quality will be akin to an Answer Print rather than a Release Print 9
Compression requirements 19 lossless and lossy compression in one codec scalability in resolution and quality Accuracy depth up to 32 Bit/component Image width and height up to (2 32-1) Quality based, VBR, CBR coding, high efficient D-cinema frame size 20 Digital production formats: 35 mm Scan 4096x3112 Cameras (DALSA, Olympus) 4064x2048, 3840x2064 (1Chip) Digital projection formats: DCI (1.85:1) 3790x2048 / 2842x1536 (2:1) 4096x2048 (2.39:1) 4096x1714 / 3672x1536 10
Digital Cinema requirements on bit depth and Color 21 - Production - Postproduction - Distribution - Projection Headroom 2-6 Bit Production 10-16 Bit/Component RGB 444 Projection 8-10 Bit/Component YUV 422 S/N headroom > 10 db Digital Cinema System integration 22 Advantages: - Editing (Frame access) - Network (Scalability) - Lossless compression 11
Financial Implications 23 Film Hardware costs are relatively inexpensive Media costs are expensive Studios absorb most of the release costs D-Cinema Hardware costs are expensive Media costs are inexpensive Studios will absorb most of the capital costs Release Dates 24 Content Value The value of a movie decreases with time Release dates are staggered worldwide due to mastering and distribution costs D-Cinema will decrease duplication and distribution costs making simultaneous release realizable The aim of the studios is to have worldwide day and date release of movies Provides more effective marketing Diminishes the value of pirated content 12
Who determines the standards? 25 The very companies that will be funding the conversion from film to D-Cinema In the US, it will be the studios (Hollywood) Outside the US is still unclear The studios do not have the resources or the experience for standardization They will rely on external standards bodies SMPTE will be the key organization Who are the bodies? 26 Advisory Groups: DCI EDCF Standards Bodies: SMPTE JPEG MPEG ITU-R 13
Digital Cinema Initiative (DCI) 27 Formed by the seven Hollywood studios Disney Warner Brothers Columbia Universal MGM Paramount Fox DCI s Role 28 Determine the technical and financial models for D-Cinema Create a common technical specification to meet the needs of the studios Recommendations should be determined by the institutions with the most risk Study potential business models for the deployment of Digital Cinema The cost of deployment is estimated to be approximately $2.5B for the US market 14
SMPTE 29 Society of Motion Picture and Television Engineers Main Technology Committee for D-Cinema is DC28 DC28.10 Mastering DC28.20 Distribution DC28.30 Exhibition Standards from other technology committees will also be adopted for D-Cinema i.e. W25 MXF wrapping DC28 Scope 30 Focus is on digital mastering, delivery and playback of first-run motion pictures this does not include production and post -production it begins with digitally mastering the version that contains all final creative decisions for picture and sound 15
DC28 Scope 31 DC28 is not presently concerned with alternative entertainment delivered to theatres e.g. live events using television-type technology DC28 recognizes that other standards bodies may be more interested in such alternative entertainment Alternative Content 32 E-Cinema is being studied by other groups The likely origination points are: Sports Trucks Concert Halls Pre-recorded/Pre-packaged media Will likely use a separate distribution channel different from D-Cinema Independent Films may also be distributed using this method Lower budget movies 16
Alternative Content 33 Again, technological decisions will be driven by the content originator Most likely to be broadcasters Or entities using broadcast equipment The most viable solutions will be technologies already used or slated to be used in television MPEG-2 using high bitrates MPEG-4 AVC which is likely to supplant MPEG-2 What about outside the US? 34 Most external bodies are proposing multi -tiered standards The top tier will be conformant to DCI s recommendations Lower tiers generally conform to existing broadcast standards Hollywood Content is the predominant revenue mechanism for domestic and foreign theaters Approximately $20B in worldwide revenue 17
Where does JPEG compression fit? 35 Source content will be delivered in the form of the DCDM Digital Cinema Distribution Master Currently stored in 2k or 4k at 16 bits per component DCI has adopted JPEG 2000 as compression standard Output codestream will be wrapped into an SMPTE defined MXF file Individual frames will be wrapped Three potential scenarios Packaging JPEG2000 36 Not all theaters will have 4k projectors Distributors would like to send a single 4k package to all theaters This will simplify content inventory 2k theaters will need to process 4k data into 2k data Packaging method can simplify downconversion JPEG 2000 is scalable 18
Security in digital cinema 37 Security issues in digital cinema are among the most critical requirements Mostly content pirating counter measures Security requirements in digital cinema (DCI) Securing physical container and/or distribution links Encryption of the content file at every step Watermarking of the content at some steps Forensic tracking Key management Data integrity verification Types of attack 38 Sniffing the communication links Stealing the physical support Camcoder attack 19
Camcorder attack 39 A pirate (sometimes with the consent of cinema personnel) can record the movie from projection screen It is forbidden to bring a camcorder to a movie theater Watermarking requirements in digital cinema 40 Watermarking for illegitimate copy detection and as a critical component of overall secure production /distribution of digital cinema Watermarking to prevent or disrupt camcorder piracy Watermarking for forensic tracking (fingerprinting) 20
Watermarking requirements in digital cinema (cont d) 41 Digital Cinema watermarking technology goals include: Invisibility, or at least imperceptibility, to the viewing audience Recoverability (robustness to geometric distortion and robustness to various malicious attacks such as stirmark) Flexibility (embedding at more than three different stages, one-pass embedding) Cost-effectiveness (embedding in real-time within a secure media block having weak processing power and small memory capacity) Renewability and extensibility (algorithms can be replaced or upgraded, with backward compatibility) Collusion resistance (number of copies that can be colluded with an arbitrary best-known collusion algorithm to result in a new copy that still reveals at least one of the colluders) Reliable detection (10-3 ) & Low false positive detection 10-12 Detection time delay (within 5 minutes) Original content can be used in watermarking extraction 21