Digital Cinema Package - AbsoluteAstronomy.com

A Digital Cinema Package (DCP) is a collection of digital files used to store and convey Digital cinema

Digital cinema

Digital cinema refers to the use of digital technology to distribute and project motion pictures. A movie can be distributed via hard drives, optical disks or satellite and projected using a digital projector instead of a conventional film projector...

(DC) audio, image, and data streams.

The term has been defined by Digital Cinema Initiatives

Digital Cinema Initiatives

Digital Cinema Initiatives, LLC or DCI is a joint venture of major motion picture studios, formed to establish a standard architecture for digital cinema systems.The organization was formed in March 2002 by the following studios:* Metro-Goldwyn-Mayer...

, LLC in their recommendations for packaging of DC contents. General practice adopts a file structure that is organized into a number of usually multi-gigabyte

Gigabyte

The gigabyte is a multiple of the unit byte for digital information storage. The prefix giga means 109 in the International System of Units , therefore 1 gigabyte is...

size Material eXchange Format (MXF) files, which are separately used to store audio and video streams, and auxiliary index files in XML

XML

Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....

format.

The MXF files contain streams that are compressed, encoded, and encrypted, in order to reduce the huge amount of required storage and to protect from unauthorized use. The image part is JPEG 2000

JPEG 2000

JPEG 2000 is an image compression standard and coding system. It was created by the Joint Photographic Experts Group committee in 2000 with the intention of superseding their original discrete cosine transform-based JPEG standard with a newly designed, wavelet-based method...

compressed, whereas the audio part is linear PCM. The adopted (optional) encryption standard is AES

Advanced Encryption Standard

Advanced Encryption Standard is a specification for the encryption of electronic data. It has been adopted by the U.S. government and is now used worldwide. It supersedes DES...

128 bit in CBC mode.

The newer SMPTE standards are used to conform the recommendations among different tool vendors and producers. Interop, the legacy DCP standard, is still required to be supported by DCP players.

Technical specifications

The DCP root folder (in the storage medium) contains a number of files, some used to store the image and audio contents, and some other used to organize and manage the whole playlist.

Picture MXF files

Picture contents may be stored in one or more reels corresponding to one or more MXF

MXF

Material eXchange Format is a container format for professional digital video and audio media defined by a set of SMPTE standards.- A brief summary of MXF :...

files. Each reel contains pictures as MPEG-2

MPEG-2

MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission...

or JPEG 2000

JPEG 2000

essence, depending on the adopted codec. MPEG-2 is no longer compliant with the DCI specification. JPEG 2000 is the only accepted compression format.

Supported frame rates are:
- SMPTE (JPEG 2000)
  - 24, 25, 30, 48, 50, and 60 fps @ 2K
  - 24, 25, and 30 fps @ 4K
  - 24 and 48 fps @ 2K stereoscopic
- MXF Interop (JPEG 2000) - Deprecated
  - 24 and 48 fps @ 2K (MXF Interop can be encoded at 25 frame/s but support is not guaranteed)
  - 24 fps @ 4K
  - 24 fps @ 2K stereoscopic
- MXF Interop (MPEG-2) - Deprecated
  - 23.976 and 24 fps @ 1920x1080
Maximum frame sizes are 2048x1080 for 2K DC, and 4096x2160 for 4K DC. Common formats are:
- SMPTE (JPEG 2000)
  - Flat (1998x1080 or 3996x2160), ~1.85:1 aspect ratio
    Aspect ratio
    The aspect ratio of a shape is the ratio of its longer dimension to its shorter dimension. It may be applied to two characteristic dimensions of a three-dimensional shape, such as the ratio of the longest and shortest axis, or for symmetrical objects that are described by just two measurements,...
  - Scope (2048x858 or 4096x1716), ~2.39:1 aspect ratio
  - HDTV (1920x1080 or 3840x2160), 16:9 aspect ratio (although not specifically defined in the DCI specification, this resolution is DCI compliant per section 3.2.1.2).
  - Full (2048x1080 or 4096x2160)
- MXF Interop (MPEG-2) - Deprecated
  - Full Frame (1920x1080)
12 bits per pixel precision (36 bits total)
XYZ colorspace
CIE 1931 color space
In the study of color perception, one of the first mathematically defined color spaces is the CIE 1931 XYZ color space, created by the International Commission on Illumination in 1931....
Maximum bit rate
Bit rate
In telecommunications and computing, bit rate is the number of bits that are conveyed or processed per unit of time....

is 250 Mbit/s (1.3 MBytes per frame at 24 frame/s)

Sound MXF files

Sound contents are stored in reels, too, corresponding to picture reels in number and duration. In case of multilingual features, separate reels are required to convey different languages. Each file contains linear PCM essence.

Sampling rate is 48,000 or 96,000 samples per second
Sample precision of 24 bits
Linear mapping (no companding
Companding
In telecommunication, signal processing, and thermodynamics, companding is a method of mitigating the detrimental effects of a channel with limited dynamic range...

)
Up to 12 independent channels.
WAV container

Composition playlist file

Defines the playback order during presentation. The order is saved in XML

XML

format in this file; each picture and sound reel is identified by its UUID. In the following example, a reel is composed by picture and sound:



 

  urn:uuid:632437bc-73f9-49ca-b687-fdb3f98f430c

  

   

    urn:uuid:46afe8a3-50be-4986-b9c8-34f4ba69572f

    24 1

    340

    0

    340

    24 1

    2048 858

   

   

    urn:uuid:1fce0915-f8c7-48a7-b023-36e204a66ed1

    24 1

    340

    0

    340

Packing list file

All files in the composition are hashed and their hash is stored here, in XML format. This file is generally used during ingestion in a digital cinema server to verify if data have been corrupted or tampered with in some way. For example, an MXF picture reel is identified by the following element:



 

  urn:uuid:46afe8a3-50be-4986-b9c8-34f4ba69572f

  iqZ3X7TdAjAqniOxT2/hj66VCUU=

  210598692

  application/x-smpte-mxf;asdcpKind=Picture

The hash value is the Base64

Base64

Base64 is a group of similar encoding schemes that represent binary data in an ASCII string format by translating it into a radix-64 representation...

encoding of the SHA-1 checksum

Checksum

A checksum or hash sum is a fixed-size datum computed from an arbitrary block of digital data for the purpose of detecting accidental errors that may have been introduced during its transmission or storage. The integrity of the data can be checked at any later time by recomputing the checksum and...

. It can be calculated with the command

openssl sha1 -binary "FILE_NAME" | openssl base64

Volume index file

A single DCP may be stored in more than one medium (e.g., multiple hard disks). This file is used to identify the volume order in the series.

3D DCP

The DCP format is also used to store stereoscopic (3D) contents. In this case, 48 frames per second are used, with frames alternating for left eye and right eye pictures. Since the maximum bit rate is always 250 Mbit/s, this results in a net 125 Mbit/s for single frame, but the visual quality decrease is generally unnoticeable.

DCP creation

Most film producers and distributors rely on digital cinema encoding facilities to produce and quality control check a digital cinema package before release. Facilities follow strict guidelines set out in the DCI recommendations to ensure compatibility with all digital cinema equipment. For bigger studio release films, the facility will usually create a DCDM (Digital Cinema Distribution Master).

A DCDM is the post-production step prior to a DCP. The frames are in XYZ TIFF format and both sound and picture are not yet wrapped into MXF files. A DCP can be encoded directly from a DCDM. A DCDM is useful for archiving purposes and also facilities can share them for international re-versioning purposes. They can easily be turned into alternative version DCPs for foreign territories. For smaller release films, the facility will usually skip the creation of a DCDM and instead encode directly from the DSM (Digital Source Master) the original film supplied to the encoding facility. A DSM can be supplied in a multitude of formats and colour spaces. For this reason, the encoding facility needs to have extensive knowledge in colour space handling including, on occasion, the use of 3D LUTs

3D LUT

In the film industry, 3D LUTs are used to calculate preview colors for a monitor or digital projector of how an image will be reproduced on the final film print. A 3D LUT is a 3D lattice of output color values. Each axis is one of the 3 input color components and the input color thus defines a...

to carefully match the look of the finished DCP to a celluloid film print. This can be a highly involved process in which the DCP and the film print are "butterflied" (shown side by side) in a highly calibrated cinema.

Less demanding DCPs are encoded from tape formats such as HDCAM SR. Quality control checks are always performed in calibrated cinemas and carefully checked for errors. QC checks are often attended by colourists, directors, sound mixers and other personnel to check for correct picture and sound reproduction in the finished DCP.

DCP encryption

The AES encryption is applied to all MXF files. The encryption keys are generated and transmitted via a KDM (Key Delivery Message) to the projection site. KDMs are XML files that can be opened only by the destination device. A KDM is associated to each playlist and defines the start and stop times of validity for the projection of that particular feature.

DCP delivery methods

The most common method uses a specialist hard disk (most commonly the CRU DX115) designed specifically for digital cinema servers to ingest from. These hard drives were originally designed for military use but have since been adopted by digital cinema for their hard wearing and reliable characteristics. The hard drives are usually formatted in the Linux

Linux

Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

EXT2

Ext2

The ext2 or second extended filesystem is a file system for the Linux kernel. It was initially designed by Rémy Card as a replacement for the extended file system ....

or EXT3

Ext3

The ext3 or third extended filesystem is a journaled file system that is commonly used by the Linux kernel. It is the default file system for many popular Linux distributions, including Debian...

format. Usually the iNode is set to 128 bits to avoid compatibility issues with some servers. Also, NTFS and FAT32 are occasionally used but they are generally not considered flexible enough since some Linux based digital cinema servers (such as those made by Dolby and Sony) are unable to read these formats. Hard drive units are normally hired from a digital cinema encoding company, sometimes in quantities of thousands. Drives are commonly shipped in protective hard cases. The drives are delivered via express courier

Express mail

In most postal systems express mail refers to an accelerated delivery service for which the customer pays a surcharge and receives faster delivery. Express mail is a service for domestic mail and is governed by a country's own postal administration...

to the exhibition site. Other, less common methods adopt a full digital delivery, using either dedicated satellite links or high speed Internet connections.

DCP creation tools

DCP creation tools
Name	Frame size	Frame rate Frame rate Frame rate is the frequency at which an imaging device produces unique consecutive images called frames. The term applies equally well to computer graphics, video cameras, film cameras, and motion capture systems... (frame/s)	Sampling rate Sampling rate The sampling rate, sample rate, or sampling frequency defines the number of samples per unit of time taken from a continuous signal to make a discrete signal. For time-domain signals, the unit for sampling rate is hertz , sometimes noted as Sa/s... (kHz)	Input formats	Notes	OS Operating system An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...	License
2DCP_GUI	2K, 4K	24, 48	48, 96	Multiple	Picture scaling	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Freeware Freeware Freeware is computer software that is available for use at no cost or for an optional fee, but usually with one or more restricted usage rights. Freeware is in contrast to commercial software, which is typically sold for profit, but might be distributed for a business or commercial purpose in the...
CineCert AS-DCP File Access Library	2K, 4K	24, 25, 30, 48, 50, 60	48, 96	J2K, WAV, XML	Needs separate codec	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal... , Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems... , Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...	BSD-like
Doremi CineAsset	2K, 4K	24, 48	48	Multiple video formats, TIFF, DPX, and others		Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal... , Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...	Commercial license
Cinemaslides	2K, 4K	24, 48	48, 96	All known image and audio formats	Encryption, KDM generation. Needs separate codec	Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...	GPLv3
DVS Clipster	2K, 4K	24, 48	48	Multiple formats		Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Commercial license
DCP Builder	2K, 4K	24, 48	48, 96	Multiple video formats, BMP, TIFF, JPEG, DPX, PNG, SGI, TGA	No encryption, needs registration	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal... , Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems... , Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...	Freeware Freeware Freeware is computer software that is available for use at no cost or for an optional fee, but usually with one or more restricted usage rights. Freeware is in contrast to commercial software, which is typically sold for profit, but might be distributed for a business or commercial purpose in the...
DCPC - Digital Cinema Package Creator	2K, 4K	24, 25, 30, 48, 50, 60	48	Multiple formats	Needs separate codec	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
Prism DCP Encoder	2K, 4K	24, 48	48	DPX, CIN, TIFF, PNG, BMP, TGA, JPG	Picture scaling presets	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Commercial license
Inition DCP Pro	2K	24	48	Multiple formats	Network encoding of JPEG 2000 files	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Commercial license
DCP Tool	2K, 4K	24, 48	48	TIFF, DPX, WAV, AIFF	Two separate tools	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Commercial license
Dietrich	2K, 4K	24, 25, 30, 48, 50, 60	48, 96	DCDM, DCP, MXF, XML	Encryption, key management, KDM generation, package validation, subtitles	Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
Fraunhofer IIS easyDCP Creator	2K, 4K	24, 25, 30, 48, 50, 60	48	DPX, TIFF, J2K, JPEG, GIF, PNG, BMP		Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal... , Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...	Commercial license
Fraunhofer IIS easyDCP Creator+	2K, 4K	24, 25, 30, 48, 50, 60	48	DPX, TIFF, J2K, JPEG, GIF, PNG, BMP	Supports KDM and encryption with included easyDCP KDM Generator	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal... , Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...	Commercial license
MagnaMana FinalDCP	2K, 4K	24	48	AVI, QuickTime		Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal... , Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...	Commercial license
Extron J2KENC	2K	24	48	BMP, DPX, PNG, TGA, TIFF		Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Commercial license
opencinematools	2K, 4K	24, 48	48	TIFF		Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal... , Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems... , Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...	BSD
OpenCubeDCP	2K, 4K	24, 48	48	DPX, CIN, TIFF, TGA, BMP, SGI, RAW, RGB, YUV, WAV	Rack mounted unit	Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...	Commercial license
OpenDCP	2K, 4K	24, 25, 30, 48, 50, 60	48 , 96	TIFF, DPX, CIN	XML file generation with digital signatures	Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal... , Mac OSX, Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...	GPL
intoPIX PRISTINE J2K Accelerator	2K, 4K	24, 25, 30, 48, 50, 60		Multiple formats	Up to 100 fps in 2K, up to 24 fps in 4K, PCIe board	Windows, Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...	Commercial license
QubeMaster Pro	2K, 4K	24, 25, 30, 48, 50, 60	48, 96	Multiple formats DPX, CIN, TIFF, TGA, BMP, AVI, QT, ASF, AUD, WAV, TXT		Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Commercial license
Dolby SCC2000	2K, 4K	24, 25, 30, 48, 50, 60	48, 96	All common D-Cinema master file formats	Standalone unit, render farm	Linux	Commercial license
CineCert Wailua DCP Mastering System	2K, 4K	24, 25, 30, 48, 50, 60	48, 96	TIF, DPX, J2K, MXF, WAV, XML	DCP testing (individual assets and entire packages), Support for creating partial ("supplemental") DCPs, Encryption, KDM creation, Extensive Python API; Kii add-on module required for JP2K compression, colorspace conversion, and pixel array resizing	Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems... , Linux Linux Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...	Commercial License
QuVIS Wraptor	2K	24	48	Multiple formats	Plugin for Compressor Compressor (software) Compressor is a video and audio media compression and encoding application for use with Final Cut Studio and Logic Studio on Mac OS X. It can be used with Qmaster for clustering.-History:... in Final Cut Studio Final Cut Studio Final Cut Studio is a professional video and audio production suite for Mac OS X from Apple Inc., and a direct competitor to Avid Media Composer in the high-end movie production industry... . Does not work with compressor 3.05 or higher.	Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...	Commercial license
QubeMaster Xpress	2K	24	48	Multiple formats		Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Commercial license
QubeMaster Xport	2K, 4K	24, 25, 30, 48, 50, 60	48	Multiple formats	Plugin for Compressor Compressor (software) Compressor is a video and audio media compression and encoding application for use with Final Cut Studio and Logic Studio on Mac OS X. It can be used with Qmaster for clustering.-History:... in Final Cut Studio Final Cut Studio Final Cut Studio is a professional video and audio production suite for Mac OS X from Apple Inc., and a direct competitor to Avid Media Composer in the high-end movie production industry... .	Mac OS X Mac OS X Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...	Commercial license

External links

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