Synchronized Multimedia Markup Data … Multimedia Markup Language (SMIL) © Oxford University Press 2007. All rights reserved. 2 Language required to specify the multi- modal multimedia

© Oxford University Press 2007. All rights reserved. 1

Data Synchronization in Mobile Computing Systems

Lesson 12Synchronized Multimedia Markup

Language (SMIL)


Language required to specify the multi-modal multimedia communication

• Mobile devices not only have to synchronize data but also multimedia (music, video clips, images, and slide shows)

• The transmitted text shown onto the display of the video clip

• The text also rendered with the voice• The displayed text, images, and audio

needs to be synchronized


Language required to specify the multi-modal multimedia communication

• To specify the synchronization messages in order to enable appropriate synchronization and for integration of multi-modal multimedia communication


Multi-modal

• Usage of different modes—text, image, video, or audio

• Multi-modal communication integrates and synchronizes multimedia.


SMIL

• Used for text, speech, or multimedia integration for multi-modal communication

• Like SyncML, the SMIL based on XML• SMIL version 2.1 enables coding of

messages for interactive audio–visual presentations

• The coding of SMIL messages needs a simple text editor


SMIL

• SMIL specifies the standard ways and tags which integrate text, images, and streaming audio and video

• SMIL─ a W3C council (World Wide Web Consortium)


Coding for a text-to-speech synthesis (TTS) engine

• TTS deployed in automobiles and many other applications

• If the driver of an automobile attempts to read a text message, his attention may get diverted

• TTS engine converts text messages to voice messages

• SMIL can be used for coding the TTS engine


SMIL features

• Just as SyncML refers to objects by URIs, SMIL refers to multimedia objects by URLs ( (universal resource locators)

• SMIL provides the commands for Multimedia objects sharing between presentations and may be required to be stored on different servers for load balancing the actions


SMIL features

• SMIL provides commands for Different media objects required to be transmitted at different bandwidths

• SMIL document has two components(i) a header between start and end tags, <header> and </header> and (ii) a body between start and end tags, <body> and </body>


SMIL Features

• Due to multimedia synchronization, the <body> section also provides the timing information


Sample Code 9.4

<smil><SyncHdr>

…</SyncHdr><SyncBody>…

</SyncBody></smil>


SMIL Tags within the <SyncBody>

1. <layout> within the header element to specify layout of SMIL document

2. <seq> for sequential operations within the body element. The specified operations should be performed in sequence


SMIL Tags within the <SyncBody>

3. <par> for parallel operations within the body element. The specified operations should be carried out in parallel.

4. <switch> for a different set within the body element for presenting multimedia contents


Sample Code

1. <SyncBody><seq> <!- - Source of WBXML text file is my.wml, maximum period 10 s, duration is 1 s,

repetition is 5 times- - ><text src = “my.wml” max= “10s” dur = “1s” repeatCount =”5”/>


Sample Code

<!- - Source of video file is my.mpg, identifier is my_vid and end duration = 10s. - - > <video src = “my.mpg” id = “my_vid” end = 10s/>

</seq></SyncBody>


Sample Code

2. <SyncBody><!- - Assume that all operations image and

audio begin in parallel and begin at 2s” -- >

<par begin = “2s”> <!- - Source of image file is myimage.jpg,

end is 2s and freeze on display for 2s - ->


Sample Code

<img src = “myimage.jpg” begin = “2s” end myimage.end – 2s” fill = “freeze”/>

<!- - Source of audio file is myaudio.wav, id is “my_id”, begin at t = 0s for 10s duration. - - >

<audio id = “my_id” src = “myaudio.wav” begin = “0s” dur = “10s” /></par>

</SyncBody>


Multimedia messaging service (MMS)

• MMS is the video and picture equivalent of SMS, is a subset of SMIL

• It can be implemented on handheld computers and mobile devices


SMIL messages

• Can be structured as in a document object model (DOM) tree

• DOM tree specifies a tree-like structure of the tags


SMIL messages

• Tree-like structuring of objects as in URI specifications

• In a DOM tree, a manager is the root and SMIL messages are the branches and leaves

• SMIL messages scheduled using SMIL scheduler software


SMIL Parsing

• Just as an XML document or SyncML message, SMIL message needs to be parsed

• A DOM interface specifies the parsing and layout


Summary

• Funambol provides Java-based synchronization using SyncML messages

• SMIL enables coding of messages for interactive audio–visual presentations

• SMIL specifies the standard ways and tags which integrate text, images, and streaming audio and video


End of Lesson 12Synchronized Multimedia Markup

Language (SMIL)

Documents

Synchronized Multimedia Markup Data … Multimedia Markup Language (SMIL) © Oxford University Press 2007. All rights reserved. 2 Language required to specify the multi- modal multimedia