Data Synchronization in Mobile Computing Systems Lesson 12 Synchronized Multimedia Markup Language (SMIL)

Language required to specify the multimodal 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 Oxford University Press 2007. All rights reserved. 2

Language required to specify the multimodal multimedia communication To specify the synchronization messages in order to enable appropriate synchronization and for integration of multi-modal multimedia communication Oxford University Press 2007. All rights reserved. 3

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 Oxford University Press 2007. All rights reserved. 5

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) Oxford University Press 2007. All rights reserved. 6

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 Oxford University Press 2007. All rights reserved. 7

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 Oxford University Press 2007. All rights reserved. 8

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> Oxford University Press 2007. All rights reserved. 9

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 Oxford University Press 2007. All rights reserved. 12

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 Oxford University Press 2007. All rights reserved. 13

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 /> Oxford University Press 2007. All rights reserved. 14

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> Oxford University Press 2007. All rights reserved. 15

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 - - > Oxford University Press 2007. All rights reserved. 16

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> Oxford University Press 2007. All rights reserved. 17

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 Oxford University Press 2007. All rights reserved. 18

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 Oxford University Press 2007. All rights reserved. 20

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 Oxford University Press 2007. All rights reserved. 22