Transcript Document

The DCI Specification for
Post Production
IBC
September 11, 2005
DCI Specification

Picture
–
–
–
–

12bit X’Y’Z’ color
2048x1080 24p/48p or
4096x2160 24p
JPEG2000 compression
Sound
–
16 channels max; 24bits deep;
48/96Ks/sec
NO COMPRESSION

Flow and Reels
–
–
–

Elements delivered as package or separately
Broken into “reels”
Playlists reconstruct playout in theater
Packaging (MXF)
–
Delivery of encrypted elements using MXF
First an overview, then review each
section
–

Subtitles
–
–

Security / Encryption
–
Elements encrypted and keys delivered for
playout
Text rendering in system or
PNG Alpha channel
17 July 2015
2
Simple Functional Flow
for Digital Cinema
Digital
Cinema
Distribution
Master
(DCDM)
Similar to Dupe
Neg
17 July 2015
Digital
Cinema
Package
Digital
Cinema
Server
Digital
Cinema
Projector
(DCP)
Similar to
Release Print in
Film Cans
Similar to
Platter Reel
3
Digital Cinema Workflow
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4
Digital Cinema Content
Preparation Flow and Terminology

Encoding
– The process of compressing the image content to condense the
large size of the file so it is manageable for distribution and
storage
– The reverse process of this is called decoding

Encryption
– The process of scrambling the content files such that a key is
required to unlock the scrambled files
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17 July 2015
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Creating the Digital Cinema
Package

Composition
– A feature, a trailer, a logo, a short or an advertisement.
Any single complete piece of content.

Packaging
– Assembling together all of the encoded and encrypted files
and wrapping them up into a complete package for
shipment.
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Packaging Format




Based upon “Reels”
Reels can be electronically
spliced together to create a
“Composition” (Feature,
Trailer, Logo etc.)
Reels include parallel Track
Files of different Picture,
Sound, Subtitles etc.
Track Files are tied together
by Composition Playlists
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Example Composition Playlist
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9
Key Management

Key Management
– The process of creating and distributing the Keys required
to unscramble the content at the authorized auditorium

Key Delivery Message
– The mechanism that is used to transport the keys used to
unlock the content in the auditorium at play out.
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Theatre Playback System

Server
– The device that plays back the content in the theatre.
Similar to a specialized computer like a Media PC or Tivo
for the home.

Show Playlist
– The method used to connect the Compositions together in
the Theatre to create a complete show.
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Exhibition Show Play List
SHOW PLAY LIST
EXIBITION STORAGE
Advertisement
Start
Composition #1
Trailer #1
Start
Composition #2
Trailer #2
Start
Composition #3
Start
Composition #4
Start
Trailer #3
Composition #5
Logo
Start
Composition #6
Start
Composition #7
Feature
Rating Card
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Basic Security

Watermarking / Fingerprinting
– The process of marking the content with unique marks in the picture
and the sound to trace the origin of stolen content

Link Encryption
– A connection from the server to the projector needs to be scrambled so
that someone can not steal the content by tapping into this link.

Logging
– The recording of events that take place while a show is played out in
the auditorium. Provides audit information back to the studio.
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DCI Specification
Details
DCI Major Issues






Image resolution and Color
Audio bit depth and sample rates
Compression type and bit rate
Subtitle types and limitations
Packaging and metadata
Security and Key Management
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DCI Specification

Picture
–
–
–
–

12bit X’Y’Z’ color
2048x1080 24p/48p or
4096x2160 24p
JPEG2000 compression
Sound
– 16 channels max; 24bits
deep; 48/96Ks/sec
– NO COMPRESSION


Subtitles
– Text rendering in system
or
– PNG Alpha channel
17 July 2015
WorkFlow and Reels
– Elements delivered as
package or separately
– Broken into “reels”
– Playlists reconstruct
playout in theater

Packaging (MXF)
– Delivery of encrypted
elements using MXF

Security / Encryption
– Elements encrypted and
keys delivered for playout
16
Picture DCDM

Resolution
– 2048x1080 OR 4096x2160 Containers
 Only active pixels are transported
– 24/48 frames per sec for 2k
– Reel per Reel configuration
– Academy “2 Pop” Leader
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Level
1
1
Ph
4096
3996
Pv
1714
2160
AR
2.39
1.85
Pixel
Aspect
Ratio
1:1
1:1
2
2
2048
1998
858
1080
2.39
1.85
1:1
1:1
17
DCI Requirements
Image - Dynamics
Matt Cowan
Entertainment Technology
Consultants
www.etconsult.com
X’Y’Z’ Color Encoding
for Digital Cinema Distribution
Glenn Kennel
IBC D-Cinema Update
September 11, 2005
Color Encoding




CIE XYZ Color Primaries
Gamma 1/2.6 Transfer Function
12 bits per channel
Metadata for downstream gamut
mapping- describes color gamut that is
used in the master
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Visible
and XYZ
Y
Visible colors
Display
Primaries
Displayable
colors
XYZ encoding
Space (triangle)
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Z
21
X
Color Encoding
Primaries

XYZ color primaries
(1931 CIE standard)
– Device independent, colorimetric representation
– Encompasses full color gamut
– Luminance isolated to one component (Y)
Encoding
Primaries
x
y
u’
v’
X
1.0000
0.0000
4.0000
0.0000
Y
0.0000
1.0000
0.0000
0.6000
Z
0.0000
0.000
0.0000
0.0000
Note: x, y, u’ ,v’ refers to the chromaticity coordinates defined by the CIE.
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Color Encoding
Linear Matrix

R’G’B’ color space of Reference Projector is converted to
device-independent X’Y’Z’ color space of DCDM with a linear
space matrix
R’G’B’
2.6
2.6
RGB
[ ]
XYZ
1/2.6
X’Y’Z’
 X  0.4452 0.2771 0.1723  RDLP 
Y   0.2095 0.7216 0.0689  GDLP 
  
 

 Z  0.0000 0.0471 0.9074  BDLP 
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Encoding
Transfer Function
L
CV  4095*  
P
1
2.6
Where:
CV is the resulting Code Value for a color component.
L is the luminance output in cd/m2
P is 52.39 (extra headroom reserved for future white point changes to
accommodate range from D55 to D65).
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Implications for
Color Correctors



Color Correctors typically process signals as R’G’B’
code values
– Gamma-corrected R’G’B’ video for television
– Logarithmic R’G’B’ printing density for film
Color Correctors can also work with X’Y’Z’ data, but
controls would need to be recalibrated.
The X’Y’Z’ color space transformation can be
implemented in the output of the color corrector.
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Cinema Projector
Transfer Function
Projector Transfer Function
48
40
Luminance (cd/m2)
 CV 
L  P *

 4095
2.6
32
24
16
8
0
0
512
1024
1536
2048
2560
3072
3584
4096
Code Value
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Cinema Projector
Linear Matrix

X’Y’Z’ color space of DCDM is converted to
Projector (device specific) RGB color space with a
linear matrix
Light
2.6
2.6
[ ]
X’Y’Z’
XYZ
RGB
Modulators
 RDLP   2.7254  1.0180  0.4402  X 
GDLP    0.7952 1.6897  0.0226  Y 

 
  
 BDLP   0.0412  0.0876 1.1009   Z 
In this example, the decoding matrix is the inverse of the encoding matrix.
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Implications for
Projectors

Digital Cinema Projector must have signal
processing to convert device-independent X’Y’Z’
code values to its native RGB.





Linearize signal (apply gamma 2.6)
Apply a device-dependent linear matrix
Correct for non-linear modulator response (if necessary)
Calibrate for screen and port glass effects.
As wider gamut projectors are introduced, gamut
mapping capability will be necessary for (today’s)
smaller gamut projectors.
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Color Processing for
Digital Intermediate
for both film and digital cinema distribution
DI- Method 1
Use a 3D LUT in color corrector or external box to mimic film print stock,
starting with Printing Density source images
1 - Color-corrected master is ready for film output (Printing Density)
2 - Render (“bake in”) the film LUT when outputting the DCDM;
Encode color to X’Y’Z’
Mastering
Projector
Dual 292
R’G’B’ 12 bits
3D Print Film LUTs
(for film matching)
Scan Film or
Import Digital Images
17 July 2015
Color Corrections
Conforming
DSM
RGB Printing Density
2
1
Color Encoding
To X’Y’Z’
DCDM
Output to film
(Laser Film Recorder)
Film IN
30
DI- Method 2
Perform color corrections from source RGB Printing Density to colorcorrected R’G’B’ DCDM.
1 - Color-corrected images are ready for color encoding to X’Y’Z’.
2 - Use an (inverse film) 3D LUT to convert from R’G’B’ DCDM to
RGB Printing Density in a 2nd pass (for film output).
Mastering
Projector
Dual 292
1
Color Encoding
To X’Y’Z’
2
3D LUT to convert to
RGB Printing Density
DCDM
Color-corrected
R’G’B’ DCDM
Scan Film or
Import Digital Images
17 July 2015
Color Corrections
Conforming
DSM
RGB Printing Density
Output to film
(Laser Film Recorder)
Film IN
31
Creating Video Masters

Video displays have a smaller color gamut (CCIR 709)
– Simple colorimetric conversion could result in clipping of out of
gamut colors
– Viewing conditions are also very different; pictures look different
on a small display in a dim (10%) surround

In theory, a 3D LUT can be built to convert to CCIR 709 color
gamut, preserving the look of the picture
– Adjusting the transfer function for color appearance
– Applying a hue-preserving “soft-clip” for out of gamut colors

A trim pass is still necessary to tune color aesthetics and
frame (pan/scan) the picture for the 4:3 full-frame video
version
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The Reference Projector




X’Y’Z’ encoding (as used here) is output-referred
Faithful color reproduction depends on careful
calibration of the mastering projector and cinema
projectors
The environment is also critical (screen quality, port
glass and ambient light must be controlled)
The Mastering Projector must have the best
available black level (sequential contrast)
– Otherwise, the cinema projector may unveil unintended
details or color errors in the blacks.
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X’Y’Z’ Conclusions
and Next Steps

Robust, device-independent output-referred color
encoding definition
– Independent of display primaries and white point


Supports future improvements in color gamut and
contrast ratio
DCI StEM test provided a proof of concept
– Color transforms were independently verified by several
companies
– Next step is to test color matching across different
projection technologies

Color correctors should implement R’G’B’ to X’Y’Z’
color conversion for DCDM output
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JPEG 2000







No temporal compression
One tile
Extracted 2k from 4k
Max bit rate 250Mb/sec - all formats
ICT required
9/7 inverse wavelet transfer function
Typical 2k 24 FPS movie: about 150GB,
4k 24 FPS Movie 300GB
17 July 2015
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DCI Specification

Picture
–
–
–
–

12bit X’Y’Z’ color
2048x1080 24p/48p or
4096x2160 24p
JPEG2000 compression
Sound
– 16 channels max; 24bits
deep; 48/96Ks/sec
– NO COMPRESSION


Subtitles
– Text rendering in system
or
– PNG Alpha channel
17 July 2015
WorkFlow and Reels
– Elements delivered as
package or separately
– Broken into “reels”
– Playlists reconstruct
playout in theater

Packaging (MXF)
– Delivery of encrypted
elements using MXF

Security / Encryption
– Elements encrypted and
keys delivered for playout
37
Sound DCDM







16 channels Uncompressed sound 48k/96k,
24bits/channel
Reference Level -20 dBFS
Broadcast WAV file format
Virtual tracks
Able to support multiple languages,
commentary, audio headphone tracks
Reel per Reel configuration
“2 Pop” each reel for sync
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Channel Mapping
AES
Pair#/Ch#
Channel
#
Label / Name
Description
1/1
1
L/Left
Far left screen loudspeaker
1/2
2
R/Right
Far right screen loudspeaker
2/1
3
C/Center
Center screen loudspeaker
2/2
4
LFE/Screen
Screen Low Frequency Effects subwoofer loudspeakers
3/1
5
Ls/Left Surround
Left wall surround loudspeakers
3/2
6
Rs/Right Surround
Right wall surround loudspeakers
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Speaker Placement
Diagram
L Vertical Front
R
Screen
Left
(1)
Left Center
(7)
(4
)
Center
(3)
LF
E
Right Center
(8)
(4
)
Right
(2)
LF
E
Top Center
Surround
Left
Surr
oun
d (5)
17 July 2015
Center Surround
LFE-Rear
Right Surround
(6)
SCREE
N
40
DCI Specification

Picture
–
–
–
–

Sound
Subtitles
– Text rendering in system
or
– PNG Alpha channel
17 July 2015
WorkFlow and Reels
– Elements delivered as
package or separately
– Broken into “reels”
– Playlists reconstruct
playout in theater
12bit X’Y’Z’ color
2048x1080 24p/48p or
4096x2160 24p
JPEG2000 compression
– 16 channels max; 24bits
deep; 48/96Ks/sec
– NO COMPRESSION



Packaging (MXF)
– Delivery of encrypted
elements using MXF

Security / Encryption
– Elements encrypted and
keys delivered for playout
41
Subtitle DCDM


Defining subtitles not a simple task
On Screen
– Part of “movie” - Localization,
translation
– For hard-of-hearing
– For foreign translation

Off Screen
– Hard-of-hearing, alt language
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Supported Subtitles

Timed Text - rendering in the projector or
server/media block or alternative display
– Selectable fonts and installed fonts

Subpicture - PNG 32bit color alpha overlay
– Bit rate limit 20Mb/sec
– Bounded rectangles at image resolution



2K or 4K
Suggested “2 Pop” on spotting cassettes
Suggested “2 pop” subtitle for QC check
17 July 2015
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DCI Specification

Picture
–
–
–
–

12bit X’Y’Z’ color
2048x1080 24p/48p or
4096x2160 24p
JPEG2000 compression
Sound
– 16 channels max; 24bits
deep; 48/96Ks/sec
– NO COMPRESSION


Subtitles
– Text rendering in system
or
– PNG 8bit Alpha channel
17 July 2015
WorkFlow and Reels
– Elements delivered as
package or separately
– Broken into “reels”
– Playlists reconstruct
playout in theater

Packaging (MXF)
– Delivery of encrypted
elements using MXF

Security / Encryption
– Elements encrypted and
keys delivered for playout
44
Example Composition Playlist
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Packaging Issues

Multiple A/B Reel Configuration
– Similar to DI post production
– Frame count list for downstream Packaging

Cue generation
–
–
–
–

FFOA First frame of action
FFOI First frame of Intermission (Optional)
LFOI Last frame of Intermission (Optional)
LFOA Last frame of Action
DCP QC
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Exhibition Show Play List
SHOW PLAY LIST
EXIBITION STORAGE
Advertisement
Start
Composition #1
Trailer #1
Start
Composition #2
Trailer #2
Start
Composition #3
Start
Composition #4
Start
Trailer #3
Composition #5
Logo
Start
Composition #6
Start
Composition #7
Feature
Rating Card
17 July 2015
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Distribution Package
17 July 2015
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17 July 2015
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DCI Specification

Picture
–
–
–
–

12bit X’Y’Z’ color
2048x1080 24p/48p or
4096x2160 24p
JPEG2000 compression
Sound
– 16 channels max; 24bits
deep; 48/96Ks/sec
– NO COMPRESSION


Subtitles
– Text rendering in system
or
– PNG Alpha channel
17 July 2015
Workflow and Reels
– Elements delivered as
package or separately
– Broken into “reels”
– Playlists reconstruct
playout in theater

Packaging (MXF)
– Delivery of encrypted
elements using MXF

Security / Encryption
– Elements encrypted and
keys delivered for playout
50
Security

Problem: Pirated Movies
– Camcorder & Digital Theft

Solution: Security
– Camcorder

Forensics/Fingerprinting marking
– Digital Theft

17 July 2015
Encryption & Key Management
51
Digital Cinema Workflow
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Digital Cinema Security Messages
Standardized Messages:
1
2
Extra-Theater Messages
Intra-Theater Messages
Key Delivery
Messages
1
Post House
SM
Studio SM
SMS
1
2
Distributor
SM
Key Repository Examples
Encrypted Keys
DCDM
ME
DCP
STORAGE
Compress Encrypt
Package
Auditorium
Outside
Theater
17 July 2015
Auditorium
SM
Inside
Theater
53
Media Block with Link
Encryption
SMS
SPB2
SPB1
STORAGE
1
MD
SM
Plain
Text
B
FM
Media Block
Plain
Text
SPB1
LE
LD
Plain
Text
Project
FM *
Projection System
* optional
17 July 2015
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Integrated Projector
Media Block
SMS
SPB2
SM
SPB1
STORAGE
MD
A
Plain
Text
Plain
Text
Project
FM
Integrated Projection System
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Theater Security System
Alternative Security
Implementation
Examples
AUDITORIUM 1
Security Network
SMS
DCP
2
STORAGE
1
SPB2
SM
A
Plain
Text
SPB1
1
1
MD
TMS
Plain
Text
Project
FM
Integrated Projection System
Security Entities:
SM = Security Manager
MD = Media Decryptor
FM = Forensic Marker
LE = Link Encryptor
LD = Link Decryptor
TMS = Theater Management System
SMS = Screen Management System
Theater
Network
Security Network
SMS
2
2
1
SPB2
Standardized Messages:
1
2
Extra-Theater Messages
Intra-Theater Messages
SPB1
MD
Notes:
· Double-lined componets are
hard-security SPB1 containers.
· Dotted components are
SPB2 containers.
· Circled numbers are the
"security interfaces."
July
2015
· Components 17
filled
with
diagonal
lines are Security Entities.
AUDITORIUM 2
SM
Plain
Text
B
FM
Plain
Text
SPB1
LE
Image Media Block
LD
Plain
Text
Project
FM *
Projection System
* optional
THEATER
56
17 July 2015
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Post Issues

Data model not HD model
– File based system

Over sampling for final DCDM
– 4096 or 2048 for finished product not OCN

New color management
– DCDM Color Encoding is X’Y’Z’
– Understand RGB to X’Y’Z’ matrix


Increased bit depth for pipeline
New Encryption and Key Management
Issues
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Various DCI Issues
IBC
11 September 2005
Walt Ordway
Chief Technology Officer
(323) 769-2890
[email protected]
17 July 2015
60
The DCI Specification

Version 1.0 of the DCI specification went on the DCI web
site at noon 27 July 2005, after the press conference

By midnight 31 July, there were over 10,000 downloads

Web site is www.dcimovies.com

You no longer need a password

Bound English copies will be available soon from Focal
Press

French and Italian versions are also in work
17 July 2015
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More Industry Goals


Development of systems compliant with the DCI spec
Manufacturers should also focus on:
– High reliability
– Ease of use
– Low maintenance

Acceptable system cost, or the business models don’t work

A beta test?
17 July 2015
62
System Compliance testing


Many companies have expressed an interest in doing system
compliance testing
The studios would like to see one set of compliance test
procedures, that anyone can use for system compliance
testing

DCI is currently working with a company to develop these
compliance test procedures

More information will follow as this moves forward
17 July 2015
63
Does DCI Go Away?

All assets are being sold

Legal and historical documentation is being identified and
put into storage

The office in Hollywood close on 30 September 2005

The DCI employees are done
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Does DCI really go away?
17 July 2015
65
The New DCI LLC

DCI LLC will enter a new phase on 1 October 2005

DCI LLC will continue as a legal entity

BUT, no employees, no offices, no weekly meetings

Administrative and technical oversight will be split between 2
studios each year (Disney and Fox will take the first year)

The 6 member studios will convene meetings whenever
required

They will continue to support and publish changes to the DCI
spec if and when required

The DCI position on security issues will continue to be
represented in SMPTE
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66
Standard Evaluation Material (StEM)
17 July 2015
67
The new StEM is here!
“StEM the Sequel”
17 July 2015
68
DCI Test DCP’s

DCI has created 5 DCP’s for initial system testing

There are 3 StEM DCP’s: 2K/24 fps, 2K/48 fps and 4K/24 fps

There are 2 Treasure Planet DCP’s: 2K/24 fps and 4K/48 fps

All 5 DCP’s use the X’Y’Z’ color space and 12 bit color

All are JPEG2000 compressed, AES encrypted and MXF
packaged

The 3 StEM DCP’s have:
– Howard Lukk and Alan Davieu talking heads on the image
– Multi-channel audio
– Subtitles
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DCI Test DCP’s


So far, 7 Digital Cinema system integrators have asked for
various versions of the DCI DCPs
Doremi and Kodak have demonstrated to DCI that they can
properly play out at least 4 of the 5 DCP’s
Note: The DCI DCP’s are not intended to test the Digital
Rights Management part of a Digital Cinema security system
as defined in the DCI specification
17 July 2015
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DCI Test DCP’s

Companies who are ready to demonstrate the play out
of DCI DCP’s can contact DCI for a copy of a test file
Walt Ordway
[email protected]
(323) 769-2890

After 30 September, contact:
Howard Lukk
[email protected]
(818) 460-5313
17 July 2015
71
Thank you
17 July 2015
72