=Paper=
{{Paper
|id=Vol-201/paper-34
|storemode=property
|title=An Integrated Framework for Automating Content Enrich Packaging and Distribution with DRM support
|pdfUrl=https://ceur-ws.org/Vol-201/44.pdf
|volume=Vol-201
|dblpUrl=https://dblp.org/rec/conf/swap/BelliniBNR06
}}
==An Integrated Framework for Automating Content Enrich Packaging and Distribution with DRM support==
https://ceur-ws.org/Vol-201/44.pdf
An Integrated Framework for Automating Content Enrichment,
Packaging and Distribution with DRM support
Pierfrancesco Bellini, Ivan Bruno, Paolo Nesi, Davide Rogai
DISIT-DSI, Distributed Systems and Internet Technology Lab
Dipartimento di Sistemi e Informatica, Università degli Studi di Firenze
Via S. Marta, 3, 50139 Firenze, Italy
http://www.AXMEDIS.org, nesi@dsi.unifi.it, http://www.dsi.unifi.it/~nesi
Office: +39-055-4796523, Fax: +39-055-4796363
Abstract valuable content products in a business to business
Content enrichment is one of the most expensive (B2B) environment.
activities related to the integration and augmentation Therefore, in the view of creating high value
of information of content elements. This activity is content, most of the above mentioned activities may be
typically performed for cultural and educational iterative and may be very expensive to be performed
content and recently also for edutainment and for the presence of the humans in the loop and for the
infotainment. AXMEDIS Framework aims at providing computational complexity of processing huge about of
technical solutions and tools for reducing costs by digital data such video, audio files, documents,
automating content production, protection and multimedia, images, etc. One of the major costs and
distribution, thus supporting activities of content problems, that lead to involve the human intervention,
enrichment. The AXMEDIS solution is based on GRID are related to the management of the IPR
technology and provides an efficient management of (Intellectually Property Right) management and
content processing and finalization as well as for clearance. For example the activity of requesting and
dynamic service discovery and composition, obtaining the authorization to use some content
distributed resource management and adaptive media elements to enrich other content: a singer biography
delivery. AXMEDIS is a large IST FP6 Integrated for an audio track, an image to enrich an audio file, a
Project of Research and Development, in which a set textual description of an image, etc.
of enabling technologies are developed to cope with For this reason, content providers, aggregators and
the above mentioned problems. distributors need flexible solutions for reducing
production costs. These goals can be reached by acting
1. Introduction on a set of factors that impact on: content modeling,
The market of digital content for entertainment and content processing, content protection, digital rights
infotainment is urging new models for integrating management, interoperability of content, component
different content aspects and in particular simple based architecture, etc.
resources with semantic and knowledge. These In order to manage the complexity of content
activities are in many cases called of content enrichment and processing for massive content
enrichment or augmentation, and in details include production, suitable architectures have to be set up to
metadata processing, annotation, extraction of allow the fast and dynamic allocation of processes and
descriptors, definition of relationships, etc., and then their supervision. On this purpose a GRID technology
of content formatting and layouting to allow exploiting can be used [1], [2], [10]. Although, there is no widely
and rendering the aggregated information in some agreed definition what GRID means, the consequences
suitable manner and not only for the indexing into a for scientific and research work, and also for the
database and search, but also for the usage from the private users are relevant. GRID computing is a form
final user that can be interested to see and navigate on of distributed computing that involves coordinating
semantic annotations. Complete the above process, the and sharing computing, application, data, storage, or
activities of content packaging, protection and network resources across dynamic and geographically
distribution of the final content based product to the dispersed organizations. GRID is already being
final users and/or to other actors for further enrichment successfully used in many scientific applications where
or for exploiting the enriched content for creating more huge amounts of data have to be processed in
reasonable time and/or stored. According to the work and content sharing via P2P and other traditional
described in this paper, the GRID Computing is channels. Almost all the AXMEDIS tools (for content
declined to the production and management of authoring, distribution and processing) can be (i)
multimedia content. It is probable that a large number manually used by end-users and/or (ii) remotely
of multimedia services (music, video, radio, television, controlled by means of external tools via dedicated
etc.) are changing towards real-time on-demand Web Services (WSs) to automate their activities. This
services: VOD, IPTV, DVB-H, I-TV, etc. Crucial permits to create a large variety of architectures,
technical issues of providing access to such services including also those based on some supervising control
are user-friendliness, universal access to services, as based on (i) Workflow Management Systems such as
well as an efficient service GRID middleware that Open Flow and in the future also with BizTalk or (ii)
enables the dynamic service discovery and some higher level AXMEDIS GRID, also called
composition, distributed resource management and AXMEDIS Content Processing, AXCP.
adaptive media production and delivery according to An AXMEDIS Content Factory can be built on the
the user needs and context. basis of AXMEDIS tools in a scalable and flexible
This paper describes how the AXMEDIS manner. Tuning for example, AXCP GRID size,
Framework and solution can address the above database size and type, number of authoring tools,
mentioned problems in an integrated manner. number and type of tools/algorithms and libraries for
AXMEDIS framework provides a set of innovations, content processing, licenses, integration support based
technical solutions and tools to allow the automation of on Workflow or not, etc.
cross media content production, packaging, protection In the rest of this section, the most relevant areas of
and distribution, including enrichment and integration AXMEDIS are described while the AXCP aspects and
[3], [7], [8], [9]. AXMEDIS is based on and extended capabilities are better described in the following
a set of standards: MPEG-21 [5], [6], XML, WSDL, sections.
XSLT, SMIL, OMA, etc. AXMEDIS Distribution tools for automating the
AXMEDIS is a large Integrated Project of Research content publication and acquisition/sharing in the
and Development partially founded by the European business area allowing the interconnection of
Commission in IST FP6 and includes more than 35 AXMEDIS Content Production Factories by means of
partners (core and affiliated) among them (in any the AXEPTools which is a secure and legal P2P tool.
specific order): University of Florence, HP, Among connected AXMEDIS Content Production
EUTELSAT, TISCALI, University Politecnic of Factories, it is also possible to make distributed queries
Catalogna, University of Leeds, Telecom Italia, BBC, to search for content, and to automatically publish and
Telecom Lituania, Giunti Ilabs, SIAE, SDAE, ELION, acquire/update content from/to the business partners,
ETRI, EPFL, FHGIGD, ACIT, AFI, STRATEGICA, etc. The tools in this area also allow scheduling content
EXITECH, XIM, University of Reading, Accademia distribution and publication towards external web
Nazionale di Santa Cecilia, etc. More technical services for example those of front end distribution
information including about how to make registration servers. The distribution tools include the AXMEDIA
and affiliation to AXMEDIS can be recovered on P2P for distributing and sharing content among final
www.axmedis.org In addition, AXMEDIS is going to users by means of secure P2P network by using
be used in VARIAZIONI eContentPlus project on BitTorrent technology.
content enrichment. The VARIAZIONI project AXMEDIS Players for content playing and execution
includes many other cultural institutions such as on several different platforms, to built specific and
ALBENIZ, Sibelius Academy, etc., and technical customized content players for PC, PDA, and mobiles,
partners GERMINUS, University Pompeo Fabra, and as Active X or plugins for other tools for enforcing
University of Florence, etc. (see [4]). the DRM.
AXMEDIS DRM Servers which are protection and
2. AXMEDIS General Overview supervising tools for registering users, certificating
In Figure 1, the technical architecture of AXMEDIS is users, authenticating devices and tools, monitoring all
reported. The whole architecture is based on a set of the activities on the AXMEDIS content on AXMEDIS
facilities organized in the so called the AXMEDIS players and tools, processing licenses, managing black
model supports and plugins. It includes a set of core lists, and collecting and reporting the information
technologies and support modules at the basis of the about content usage and rights exploitation, etc.
whole set of the AXMEDIS tools for authoring, Workflow Management tools include a set of micro
administration, content distribution, content playing, tools and interfaces which are pervasively connected to
all the AXMEDIS tools and plug-ins to allow
Fig.1 – AXMEDIS Technical Architecture.
interfacing the whole content factory to Workflow enrichment on protected and non protected content
tools such as Open Flow and BizTalk. elements.
AXMEDIS Database includes the In Fig.2, the flow starts with the
AXMEDIS/MPEG-21 database model, supporting the collection/ingestion of non protected content and
storage and access to AXMEDIS content via a set of metadata. In AXMEDIS, as well as in other
metadata for each object called AXInfo that can be architectures, the content ingestion can be performed
customized. The database also includes produced automatically collecting/crawling content and metadata
licenses for the objects, history of performed actions from legacy CMSs (Content Management Systems).
on content, potentially available rights for each digital Once the content is ingested, the content elements and
resource, models of contracts, etc. information are indexed and the AXMEDIS Factory
AXMEDIS Accounting tools allow content can be used for:
producers, distributors or collecting societies to collect • producing content in some integrated format
administrative information and reports about their and/or package (integrating/relating metadata,
content in order to gathering information about the list annotations, and digital resources, each other) and
of rights that have been exploited on their AXMEDIS indexing, storing/organizing them in some
objects by the final users and by the business users. database,
• early content enrichment by adding manually
3. Content Enrichment problems and/or automatically: (i) semantic descriptors, (ii)
On the basis of the reported technical architecture extracting content descriptors for video, audio,
(see Fig.1), the AXMEDIS framework can be used to document, multimedia, images, etc. (performing
set up several different configurations of AXMEDIS adaptation and content processing when needed),
Factories for content enrichment and production. (iii) annotations and associating them to content
In Fig. 2, a simplified flow of a possible content and its internal structure and information
enrichment process is depicted to put in evidence the (segmentation, labeling, etc.),
problems and the differences of performing the content
Fig.2 – Enrichment and distribution of protected and non protected content
• storage of the enriched content in some database, information. While the respect of IPR information on
• addition of some other clued content for preparing content distribution is enforced by means of content
the enriched content for usage, for example protection technologies and formalized in some DRM
synchronization with SMIL, SVG or integration licenses. This allows to specify for each specific
with HTML, etc. content element who is authorized to do what and with
• preparing content for distribution according to which constraints (time, location, etc.). This approach
different preferred formats (adapting the content allows creating a package that can be shared among
format and changing its layout according to different peoples and experts for manual and/or
distribution channel profile, device profile, semiautomatic content enrichment in the respect of the
network profile and also user profile), for one or IPR.
more different: Thus, the protected content can be manipulated and
o devices/tools such as: PC, PDA, Mobiles, further enriched only by authenticated and certified
STBs, etc., tools and according to the produced license that
o distribution channels such as: satellite, formalize the actions/rights that can be performed on
internet, mobile, P2P, etc., each specific content element by each specific actor of
• Content Protection: protecting content according the content enrichment process. Thus the ingestion of
to some Protection Information model that may protected content has to follow a differed path (see
depend on the channel and device and user Fig.2).
(MPEG-21 IPMP, Window Media, etc.), AXMEDIS solves the above problem providing an
• DRM Licensing: applying DRM (Digital Rights integrated framework and a number of tools for
Management) rules according to IPR information content processing and enrichment that are intrinsically
and business models obtained from some supported by DRM tools. The AXMEDIS framework
administrative CMS (Content Management is mainly based on MPEG-21 [5], [6], and OMA as
System), defining and issuing licenses (may be in cross-media models, for packaging and DRM, and
different formats) for its usage on AXMEDIS provides tools for content sharing and distribution at
tools (i.e., processing, authoring, distribution and B2B level, and it is capable to work with a
players tools), multichannel architecture for B2C distribution for the
• Content Distribution: performing the effective production of content on demand [8], [9]. The
distribution: broadcasting, P2P content sharing, AXMEDIS cross media content model attempts to
etc. wrap any digital resource in a container to make them
ready for delivering by using a large range of business
In the above described process, it has to be noted and transaction models and supporting them with some
that the ingested content can be early enriched with DRM.
annotations, semantic information, multimedia and
metadata information, including also IPR and licensing
4. Content Processing Language Features Content Formatting
The AXMEDIS Content Processing Area and the • gluing content elements together by means of
related language have been designed to provide a set of SMIL based templates and applying style sheets
features and capabilities for automating content (XSLT) to define the usage interface (format,
production and processing. layout) of the content collection and the interested
The processing algorithms are specified in terms of content usage paradigms (leaving open some
script code (Spider Monkey) allowing the parameters). For example, karaoke, collection
manipulation of complex AXMEDIS data types and browsing, selection menus, sliding presentation,
simple digital resources and content in general, and for stable background with a window with live video,
the direct access to the AXMEDIS database and animated text moving on an image, running text,
processing queries with the help of the AXMEDIS etc.;
Query Support. The available data types, operators and • optimization of styling parameters left open or
accessible algorithms allow manipulation of any digital defining them manually to arrange for example:
resources in a large number of formats for: images, best fitting of images in the screen, optimizing the
audio files, video, documents, multimedia (including amount of text in the page, best time fitting, etc.;
MPEG-4, HTML, SMIL, LOM, etc.), plus MPEG-21 Content Protection such as:
aspects, MPEG-21 DI, DID, REL, IPMP, etc. • Protection of digital resources and full objects
with their complex structure;
As regard the processing capabilities, an AXCP Rule • creation of Protection Information parameters
formalises in its language features to perform the (IPMP of MPEG-21, OMA);
following activities on content. • Applying Protection Information model to
AXMEDIS object such as, segmenting digital
Content Retrieval and Storage, Ingestion and resources, applying encryption, scrambling;
Gathering from • Posting specific protection information for each
• Content Management Systems, from file system, given object to the DRM servers;
or protocols: ODBC, MySQL, ORACLE, MS- Content Licensing
SQL, etc., files systems, http and ftp accesses; • Generating license from license model and
• Many different CMSs via Focuseek Crawler; additional information, storing licenses, posting
• AXMEDIS MPEG-21 database; them on license server automatically;
• other AXMEDIS content Factories by means of • Transcoding/translating licenses from MPEG-21
the P2P tools, namely AXEPTool; REL to ODRL OMA formats;
Content and Metadata Processing such as • verification of licenses against available rights to
• metadata manipulation, mapping and adaptation; simulate the usage from the user site;
• content adaptation, extraction of descriptors, Content Publication and Distribution towards
transcoding, synchronisation, estimation of • any distribution channel, producing programme
fingerprint, watermarking, indexing, document and its schedule;
summarization, keywords extraction; • P2P network of other AXMEDIS Factories of
• audio-video synchronisation, segmentation, content integrators, producers, and distributors.
labelling of content and definition of relationships;
Content Composition and Enrichment for Have to be highlighted that the AXCP Language
• processing resources and coupling/annotating provides a way to use C++ plug-ins and to call generic
them with metadata and semantic information; WebServices. These features can be profitably used in
• packaging content elements in AXMEDIS, content enrichment, for example calling external
MPEG-21 and OMA formats; WebServices (e.g. search engines, metadata archives,
• creation of content components or objects as a etc.) that can be used to add new metadata or to add
combinations of raw assets such as Text, Images, new content. Moreover specific plug-ins can analyze
Audio, Video, Animation, metadata, descriptors, the content using specific algorithms (image analysis,
licenses, multimedia objects such as MPEG-4, audio analysis) to infer properties that can be used to
HTML, SMIL, macromedia tool files, games, etc.; enrich the content itself.
• creation of content as linear, nested or hierarchical
combination of content components;
5. AXMEDIS Content Processing Tools The AXCP Rule Scheduler manages AXCP rules and
In order to exploit the above features, the AXMEDIS the available AXCP GRID Nodes. Each of them has a
Content Processing Area is governed by a set of tools corresponding counterpart model on the Scheduler side
as depicted in Fig.3 and described as follows. to represents its capabilities and status. Knowing the
availability and capabilities of each GRID Node is
AXMEDIS Rule Editor (see Fig.4): it is capable to mandatory to verify the suitability of the computer that
produce, debug, test and validate the executable AXCP will execute the rule. To this end, the association of
Rules. An AXCP Rule is: Rule to a GRID Node is based on the analysis of their
• written using the AXCP language for content profiles/capabilities.
production which is an extension of Java script; Each AXCP GRID Node provides its
• tested, debugged and validated on the AXMEDIS profile/capabilities descriptor during its first
Rule Editor; connection and discovery/connection in the GRID
• activated for content processing on any AXCP network, containing:
GRID Node or on a single computer; • Execution status: running, idle, etc
• used/parameterized for producing content on • Identity and information of the executor: computer
demand or to be integrated in your content factory;
• activated from your Workflow Manager engine
via web service;
Fig. 3 -- AXCP Architecture
Fig. 4 – AXCP Rule Editor
The AXCP GRID consists of a set of general purpose name, IP address, location, etc.
or specialized computers (called AXCP GRID Nodes • Capabilities: CPU, RAM, Clock, Disk Space, OS,
or Engines) to execute AXCP Rules governed by the available workload, network cost for the
AXCP Rule Scheduler. communication with the database, etc.
The processing capabilities and functionalities reported • Tools Provided: AXMEDIS Plug-Ins installed and
in the previous section and exploited from AXCP External tools Plug-In installed.
Tools and Rules are expandable by realizing or
installing a set of additional plug-ins, by using the 5.2 AXCP GRID Node
AXMEDIS Plug-in descriptor and solution. The AXCP GRID Node is an Executor of Rules
running on each GRID Node. It receives the Rule code
5.1 AXCP Rule Scheduler to be executed from the Scheduler and provides to it
The AXCP Scheduler performs scheduling of AXCP the notifications, exceptions and errors messages at
rules in GRID nodes according to the content runtime. It is a computational unit in the distributed
production and processing needs in terms of time and environment where rules are executed. It hosts the
resources. It performs the rule firing/activation, rule Spider Monkey Javascript engine for JavaScript code
executor discovering and management and rules execution and the GRID interface for the network
dispatching. It is capable to receive commands for communication. The architecture of the AXCP GRID
remote control and provide reporting (notifications, Node is mainly constituted by the following main
exceptions, logs, etc…) via a web service. components:
• Rule Executor Manager to control the Script program services, or they can serve as interfaces to
Executor; program's services. For example, an AXMEDIS JS
• Rule Executor to execute rules that include an Class that provides direct service might be one that
instance of Spider Monkey Javascript Engine handles all of an application's network access, or might
(called JS Engine). serve as an intermediary broker of database services.
The Rule Executor Manager is the interface between 6. AXCP Rules and Tools
the Scheduler and the Rule Executor. The GRID Peer An AXCP is comprised of three main sections (see
Interface allows the communication in the distribute Figs. 5). The Header contains general metadata such
environment and provides the support for: as: rule name, AXRID (Rule ID), rule version, rule
1. receiving commands, messages, requests and files type, software name, version of software, date of
from the Scheduler; production, time of production, author, affiliation,
2. sending messages, notifications, exceptions and URL, comment, last modification date and time.
files to the Scheduler; Schedule section contains temporal constraints
3. being discovered by the Scheduler during the describing the rule status (“active” or “inactive”) and
discovering phase. conditions for firing it such as: start date, start time,
The Rule Executor Manager analyses the Node to periodicity (monthly, daily, weekly, etc.), expiration
recover the information to build its profile that sends it date and expiration time. Such information is used by
to the Scheduler, when it is discovered. It stays in an the AXCP Rule Scheduler in the GRID environment
idle status until the Scheduler engages it asking to put for planning the activity and associating active rules
in execution a rule. In this case, the rule is received as with available computational resources. Definition is
an XML file, and then it is fired by the Launcher. The the section that contains the rule signature in terms of
Rule Executor Manager provides to the Rule Executor list of arguments (parameters and selections), list of
the communication support. In this way, errors, status dependences (required AXMEDIS plug-ins) and the
and the end of execution are notified to the Scheduler. script code to run. Dependences define constrains on
Finally, it provides remote control commands to kill, AXMEDIS plug-ins that has to be installed in a GRID
pause, resume, of rules and to get the status of the node.
executor. A XML formalization can be obtained from Fig. 5. An
AXCP rule can be used for different purpose in the
The Rule Executor has been designed to host the JS Content Processing Area.
Engine and run a Rule also in the debugging and check
modalities. The former modality allows debugging and
monitoring the execution of a Rule by means of traps
in the code corresponding to breakpoints (interrupting
the execution), watching variables and managing the
stack of function calls. The latter modality allows
verifying the syntax of the rule before to run
definitively in the AXCP Rule Engine, and estimating
by partial execution some parameters related to the
complexity of the rule such as: requested time
computation, amount of disk space, data transferring
time, etc.
This last modality is obtained by executing the script
without the real execution of the procedures that are
the real cost of processing, with the aim of extracting Fig. 5 – XML schema of the AXCP Rule
the main parameters that are going to influence the
execution time of the algorithm depending on the For instance, in an AXMEDIS Content Factory three
context (Executor) in which it is going to the executed. main different rules categories are used:
• Publication Rule: executed to automating the
The Spider Monkey JavaScript engine’s built-in process of publishing AXMEDIS objects from the
objects were extended by wrapping AXMEDIS data database to the distribution channel or P2P
types (AXMEDIS JS Classes), functions (JS network;
Functions) and AXCP plug-in tools deriving from the • Downloading Rule: executed to download a
AXMEDIS Framework data types. They provide direct Selection of objects from the P2P network and
move them into the temporary database for further and verification of AXCP Rules on GRID Nodes. The
inspection and Load according to a Loading Rule. model defined for describing the components allows
• Loading Rule: executed to load into the extending the capabilities of the AXCP Language and
AXMEDIS Database with a selection of objects the automatic installation of new components via the
retrieved from the P2P network; AXCP Scheduler if needed. The full documentation
can be recovered on AXMEDIS portal. AXMEDIS is
an open platform in the sense that the tools, the
Formally, the signature of the AXCP Rule is:
specifications and the formats are accessible and
R = f(S1,S2,..,Sn,P1,…,Pm) royalty free. The access to the source code of all the
tools can be easily obtained joining the AXMEDIS
Where: community.
Si is a sequence of queries, to be sent to the
AXMEDIS Database to retrieve digital object 8. Acknowledgments
(content) IDs or a set of object IDs to AXMEDIS The authors would like to thanks to all AXMEDIS
objects or a mix of them; project partners including the Expert User Group and
Pi is a parameter (basic type as integer, common all affiliated members, for their contributions, funding
string, XML string, Boolean, etc.); and collaborations. A specific acknowledgment to
f is the identifier of rule (e.g., the ID of rule); European Commission IST FP6 DG INFSO for partial
R is the consumptive result of the rule application. funding of AXMEDIS project. A warm thanks to all
AXMEDIS people that have worked in the project and
Other results are the resulting objects processed and/or sorry if they have not been involved in the paper and
produced during the execution of the Rule and they have not been mentioned.
can be directly posted into the file system or database.
9. References
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