Transcript MPEG-4 XMT-A

MPEG-4
XMT-A Format
29/11/2007
Jean-Baptiste Puibaraud & Julien Pedron
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Plan
 History of MPEG
 XMT
 XMT-A
 XMT-Ω
 From XMT to MP4
 Authoring tool
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History of MPEG
• Moving Picture Expert Group
• Standard to compress audio and digital data
(1988)
• Mostly used for Web Application, Broadcast
Television and CD-Distribution
• MPEG-1 (1991)
• MPEG-2 (1994)
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MPEG-4
• Introduced in 1998 (still developing standard)
• Based on MPEG-1 and MPEG-2
• Object-oriented composite files & support for
3D rendering
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XMT (1/2)
• eXtensible MPEG-4 Textual Format
• XML based framework for scene description
• Allows authors to exchange information
(XML is readable)
• XMT = 2 levels of textual format
XMT-Ω
XMT-A
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XMT (2/2)
Example of
MPEG-4 content
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XMT-Ω
• High Level Description
• Defines audio visual objects
• Describes temporal behavior and relationship
between the different elements
• XMT-Ω is extended from SMIL
• SMIL
 Defines markup for timing, layout, visual transition
 Used to create interactive content
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XMT-Ω ExamplE
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XMT-A
• Low Level Description
• Describe precisely each AV element using
MPEG-4 specific features
• XMT-A file = set of elements to represent
MPEG-4 system streams
• Uses Object Descriptor (OD) to provide
scene description components
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XMT-A Example
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From XMT to MP4 (1/2)
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From XMT-A to MP4 (2/2)
XMT-Ω description
XMT-A description
Data Structure
BiFS and OD
MP4
Converter
MP4 File
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Authoring Tool (1/2)
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Authoring Tool (2/2)
• GPAC (Open Source)
• IBM toolkit for MPEG-4
 Set of Java classes and APIs
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References
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Wikipedia research on MPEG-4 : http://en.wikipedia.org/wiki/MPEG-4
Overview of the MPEG-4 Standard :
http://www.chiariglione.org/mpeg/standards/mpeg-4/mpeg-4.htm
GPAC, Open Source Multimedia Framework : Jean Le Feuvre, Cyril
Concolato, Jean-Claude Moissinac
Interactive Contents Authoring System based on XMT and BIFS : Kyuheon
Kim, Injae Lee, Myungseok Ki
An XMT API for Generation of the MPEG-4 Scene Description : YeSun
Joung, Kyuheon Kim
Extensible MPEG-4 Textual Format (XMT) : Michelle Kim, Steve Wood, LaiTee Cheok
MPEG-4 Systems and Applications : Hari Kalva, Lai-Tee Cheok, Alexandros
Eleftheriadis
Design and Implementation of MPEG-4 Authoring Tool : Kwang-Yong Kim,
Hyun-Cheol Kim,Won-Sik Cheong, Kyuheon Kim
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Questions ??
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