digital cinema mastering 101
DESCRIPTION
Presented at the first-ever Sundance Institute #ArtistServices San Francisco Workshop. Graef Allen is Manager of Content Services at Dolby Laboratories in Los Angeles, California. Graef has been with Dolby for over nine years, working primarily in digital cinema mastering and distribution. Although some of her work is on studio titles, most projects are independent films or educational films for science museums. Graef spent fifteen years on the staff of the Telluride Film Festival, working in production, theatre operations, and projection.TRANSCRIPT
Digital Cinema Mastering 101
I. Introduction
II. What is a DCP?
III. The Digital Cinema Mastering Workflow
IV. DCP Duplication and Distribution
Graef Allen
Dolby Laboratories, Burbank
Introduction
The future of film…
End of 2012:
Cinema screens in US: ~40,000 Digital screens in US: ~33,500 = 84%
Cinema screens WW: ~130,000 Digital screens WW: ~90,000 = 69%
Source: Screen Digest
Nearly all cinema screens worldwide expected to be converted by 2015.
Advantages
Broad Acceptance
Cinemas (mainstream, art house)
Film Festivals (Sundance, Cannes, Berlin, Telluride, SXSW…)
AMPAS (Submission for Academy Award consideration)
Financial
Media Integrity
Advantages
Broad Acceptance
Financial
Cost for a feature film print: $1500 - $2500 (Source: Wikipedia)
Cost for a copy of a feature DCP: $150 - $650
Media Integrity
Virtual Print Fees
Ted Hope raised this issue in the Q&A, and it is definitely an important financial
consideration.
In addition to the costs for mastering and media, your distributor may be charged
virtual print fees, or “VPFs,” by theatres that book your film on DCP. VPFs are
collected by theatres to cover the cost of the upgrade to digital projection equipment.
Depending on the specific terms of your booking, the VPF could be as much as $1000
for a week-long engagement, or as little as $25 for a single off-peak screening (e.g.
Tuesday night).
A theatre that paid for its own digital equipment up front may not charge VPFs.
Virtual print fees will eventually fade away as equipment loans are paid off. New VPF
agreements have mostly ceased.
The VPF business model was introduced to spread the cost of equipment upgrades
between both exhibitors and distributors. VPF agreements probably helped to
accelerate the transition to digital cinema.
Advantages
Broad Acceptance
Financial
Media Integrity
Perfect copies (hash check verification)
Robust media, less fragile than 35mm film or Blu-ray
Sound and picture as pristine on 100th screening as on 1st
35mm Film Print Damage
Photos courtesy of Brad Miller, film-tech.com
Digital Cinema Mastering 101
I. Introduction
II. What is a DCP?
III. The Digital Cinema Mastering Workflow
IV. Digital Cinema Duplication and Distribution
Graef Allen
Dolby Laboratories, Burbank
II. What is a DCP?
DCP is a standardized delivery format. It is not a single file,
but a collection of digital files.
DCPs are intended to match or surpass the quality of 35mm
film prints.
Standards set by DCI
Digital Cinema Initiatives, a studio consortium
Today’s DCPs: Interop
Tomorrow’s DCPs: SMPTE (Society of Motion Picture and Television Engineers)
DCP: Video Files
Uncompressed video files would be too large to duplicate and
distribute easily. File sizes reduced by compressing.
Digital cinema projectors able to reproduce a broader array of
colors than computer or television monitors.
Aspect Ratios = 1.85:1 or 2.39:1 (not 1.78:1)
Codec = JPEG 2000
Maximum Bitrate = 250 Mbps (about 10 x Blu-ray data rate)
Color Space = DCI P3, mapped to XYZ
File Container = MXF (.mxf)
DCP: Audio Files
Multi-channel audio on film required compression due to
physical space restrictions.
Digital audio files are so small relative to digital video files
that compression is not used.
Uncompressed
Sample rate = 48kHz
Bit depth = 24 bit
File Container = MXF (.mxf)
Information on Film vs. Information in a DCP
Audio (Analog)
Audio (Digital)
Picture/Subtitles
DCP: CPL
Sample CPL
Video
Audio
Subtitles
Digital Cinema Mastering 101
I. Introduction
II. What is a DCP?
III. The Digital Cinema Mastering Workflow
IV. DCP Duplication and Distribution
Graef Allen
Dolby Laboratories, Burbank
Video Source Files
DCDM
Digital Cinema Distribution Master
DSM
Digital Source Master
Other sources
Tape (HDCAM / HDCAM SR / D5)
ProRes or uncompressed QuickTime
Video Workflow
DSM Digital Source Master
DPX or TIFF RGB Color
DCDM Digital Cinema Distribution
Master
16bit TIFF XYZ Color
JPEG 2000
Tape or QuickTime
extract frames
resize to 2k or 4k, convert color to XYZ
JPEG 2000 compression
Audio Source Files
Uncompressed linear PCM (digital audio)
48kHz sample rate @ 24fps
Audio commonly delivered as 48kHz @ 23.98fps, which
requires a sample rate conversion to stay in sync at 24fps.
24bit
Audio Workflow
Stereo?
Wrong sample rate?
Wrong bit depth?
Wrong file type?
5.1 or 7.1 Mono .wav Files
24bit, 48kHz @ 24fps
5.1 or 7.1 Interleaved .wav File
Tape or QuickTime
capture or extract audio
bit depth conversion
sample rate conversion
upmix
interleave file type conversion
Subtitle and Caption Source Files
CineCanvas XML
Timed Text + Associated Font File (e.g. arial.ttf)
OR
Timed Subtitle Spots + Associated .png Images
(sometimes used for Japanese, Chinese, Hebrew)
Subtitle and Caption Source Files
Sample Timed Text
Subtitles
(Partial File - Japanese)
Encryption, MXF Wrapping
JPEG 2000
Encryption
(Optional),
MXF wrapping
audio.mxf
(enc.audio.mxf)
5.1 or 7.1 Interleaved .wav File
CineCanvas Subtitles (XML),
font.ttf
Folder: CineCanvas
Subtitles (XML), font.ttf
video.mxf (enc.video.mxf)
Encryption
Optional, but most distributors require features to be
encrypted
Encryption standard is AES, Advanced Encryption
Standard: Extremely secure
Additional layer of link encryption between server and
projector applied at playback
If content is encrypted, cinemas must be supplied with
playback keys to decrypt the content.
Key Delivery Messages (KDMs)
Small XML files, generally delivered zipped by email.
Three-way lock:
Content • KDM specific to exactly one CPL.
Server • KDM specific to exactly one server.
Timeframe
• KDM only valid between specified start and end times.
Common Post Production Issues
Non-cinema frame rate
HD aspect ratio
Misidentified color space or dynamic range
Highly compressed video source
Color graded on uncalibrated monitor (cinema projector is best)
Missing sync details (no 2-pop, no countdown leader)
Sound mixed in uncalibrated room (way too loud or way too quiet)
Mislabeled audio channels
Invalid subtitle XML
Mistimed subtitle XML
Missing font file
The Final Product!
Once the DCP is packaged, it needs to be watched start to finish to check for problems. After a full QC, duplication can begin.
Feature DCP Distribution Kit
Digital Cinema Mastering 101
I. Introduction
II. What is a DCP?
III. The Digital Cinema Mastering Workflow
IV. DCP Duplication and Distribution
Graef Allen
Dolby Laboratories, Burbank
Duplication
Duplication done in batches
Multiple identical copies created at once
The smaller the master DCP, the faster each
duplication run will be
Verification by hash check
Distribution
Feature distribution on CRU Dataport HDD
FedEx, UPS, DHL
KDMs (Key Delivery Messages) sent via email
Technical support should be made available, especially
if content encrypted.
DCP’s modular structure (separate file for each
component) allows single-inventory distribution to
multiple territories.
Distribution SNAFUs
Problems can include…
Lost shipments (uncommon)
Damaged hard drives (uncommon)
Misplaced hard drives (more
common)
Server upgrades, new KDMs
needed (very common)
Projector/server subtitle rendering
problems (uncommon)