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A Multimedia Broker to Support Accessible and Mobile Learning Through Learning Objects Adaptation. Authors: PAOLA SALOMONI, SILVIA MIRRI, STEFANO FERRETTI, and MARCO ROCCETTI. Presenter: Jason Kiss. Introduction.
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A Multimedia Broker to Support Accessibleand Mobile Learning Through LearningObjects Adaptation Authors: PAOLA SALOMONI, SILVIA MIRRI, STEFANO FERRETTI, and MARCO ROCCETTI Presenter: Jason Kiss
Introduction • eLearning will become a key factor in the education of students with disabilities • Most eLearning applications are through standard PC workstations • This creates technological barriers • Deaf and Blind Students • Mobile Students (aka mobile phone access) • Learned Objects(LOs)
LOT • Learning Object Transcoder • A distributed PHP-based service-oriented system designed to deliver flexible and customized educational services for a multitude of learners, each with his/her own diverse preferences and needs
LOT – 2 Main Building Blocks • The Profiling Mechanism • Designed based on the use of the ACCLIP and the ACCMD protocols • LOT is able to produce SCORM-compliant LOs transcoded to match any given student profile The Multimedia Transcoder • Uses a web server based technology • 12000 lines of php code
Related Work • Architectural Solutions for Content Adaptation • Structuring Multimedia Contents • Scheduling the Content Adaptation Process • Profiling Users
Structuring Multimedia Contents • Infopyramid • System where different multimedia contents, including video, images, audio and text, may be converted based on an intermedia transcoding approach type • SMIL • Provides a set of programmable elements and attributes to manage both temporal and spatial media synchronizations • This markup language is currently not fully supported by all software/hardware platforms
Scheduling the Content Adaptation Process • Typically Media is organized into a Pipeline • Ridged Approach • Broker System • Intermediate System • Identifies User’s needs • Matches user to correct transcending needed • Used in LOT
Profiling Users • IMS Global Learning Consortium • Describes learners preferences and needs • Does not describe device characteristics • LO’s need both learner needs and device characteristics • Therefore research is needed in this area
Original Learning Object(LO) • A Video Content Showing the Lecturer • An Audio Content encompassing the Lecturer’s talk • Sequence of static images representing slides • A Captions Sequence (text of Lecturer’s speech) • Textual Description of each slide
Go over Scenarios for SMIL • 4 Scenarios
TRANSCODING LEARNING OBJECTS • Recording • Transcoding • Post-Production
PROFILING USERS • ACCLIP • User Preferences • Accessibility Constraints • 3 Sections • Display • Control • Content
LOT’s Functions • Brokering activity • Profiling activity • Transcoding activity • Packaging activity
How LOT Works Using Web Services Media Broker(MB) Profile Manager (PM) Package Manager(PaM) Transcoding Unit (TU) Web Services (WS Set)
Tools for Media Conversion • ImageMagick • Ffmpeg
Two More Web Services • Developed by the Authors • Convert SMIL to several XHTML documents • Manages content in form of text • Manages content in form of both text and images • Web services were developed using the PHP scripting language and exploiting the NuSOAP library
Web Services • Flexibility • Modularity • Platform Independence Caching is used heavily in LOT’s Web Services to allow for faster transcoding
Conclusion • LOT is good structure for managing media distribution over the internet • Great for personal preference or for people with disabilities • Caching is an important aspect of content distribution
QUESTIONS • ???