E GOV Universal Access Ahmed Gomaa CIMIC Rutgers University

Universal Access Any InformationOver Any Network To Any One To Any Device You want to say multimedia information varying expertise, capabilities, preferences of users You want to say multimedia information varying expertise, capabilities, preferences of users

E GOV Universal Access Example The Entrepreneur can view on the E GOV portal a set of information resources specific to his type of business on any type of internet appliance with customizable preferences based on his appliance and his own preferences and capabilities.

Problems: Multimedia Synchronization and flexible presentations. What constraints shall be added to insure presentation integrity? ( Temporal and Spatial constraints ) Personalize the Multimedia presentations based on user preferences, expertise and capabilities. The middle man (middle man sounds somewhat odd?) issue arise for converting to different formats. Adaptation of Multimedia Presentations on different hardware and software. ( OS / MM Boards / Devices ) Different Networks dealing with different protocols, How to normalize the Network delay? (What is meant by normalize??)

We need a slide here to describe the three layers the first layer the synch, constraints and the object model second the PN representation implementation using a user/web-friendly, adaptable language a figure with these 3 layers

Why Use Petri-Nets? The Above mentioned problems can be implemented by hard coded solution. ( SMIL 2.0) BUT How can we identify if there is a temporal or spatial conflict in case of Forward or Rewind? (even without ff or rewind, there could be conflicts.) How can we visualize the runtime of our presentation to prevent any deadlocks, resource constraints, or network constraints? SO We need a model to analyze and abstract the problems mentioned. Petri- Net has been used in the academic field as well as the industrial field to model different systems.

A medical Digital Library Object The video must start immediately after the image has been displayed. The text must be displayed simultaneously with the image and the video.

The digital library object is downloaded to the client machine.

Implementation

Object Plan as MOPN

DL Object Plan for the above medical object

The modified plan (with only audio and text capabilities)

Parallel and Sequential

An Adjusted plan

Server Oblet Adjusted Object Plan Multimedia Boards Audio/Video N/W delay Synchronization: Fine and coarse-grain Temporal Navigation + Spatial Constraints Client Different Devices User Capabilities Spatial& Temporal Dynamic presentation Still The MOPN may be extended (We want to extend many aspects, not just MOPN, list all the extension we talked about.)

Why SMIL XML Based. 2.Allows you to use clips in different locations. (Separate URL for each clip) 3.Time and control a presentation. (Different approaches for timing) 4.Lay out a presentation. When your presentation includes multiple clips, such as a Real Video clip playing simultaneously with text captions or banner graphics, you use SMIL to define the layout. 5.Content Control module provides alternate presentations ( multiple languages, or different bandwidths. )

Timing Styled TimingStyled Timing CSS or XSL stylesheets used to apply timing to a language- can be used for SMIL Timesheets Separate timing from both content and presentation style - can be used for SMIL Styled TimingStyled Timing CSS or XSL stylesheets used to apply timing to a language- can be used for SMIL Timesheets Separate timing from both content and presentation style - can be used for SMIL Inline syntaxInline syntax -Attributes added to language elements-Attributes added to language elements -Approach used in SMIL Inline syntaxInline syntax -Attributes added to language elements-Attributes added to language elements -Approach used in SMIL 18

SMIL Document Timing principals Interne t Timing is a relation between the 2 other entities rather than a property to them Contents Provides structure to the content and the links Formatting style and (spatial) layout of presenting the content Timing describes the temporal relations between the elements in the content and formatting section

Relation Versus Property The objective is let the list element appear each one after another. - In assign property, the order is derived from the order of the list. - In assign relation, the order has been reserved from the order of the list. This shows immediately the independence created by the principle

Timesheets may be used –Document structure and timing structure do not align –Synchronization spans multiple documents –Inline syntax impractical or illegal Copyright restrictions Digital Talking Books

Petri Net To SMIL2.0 Equals ( SYNC): | | image | | text | | Audio 30s After ( Before): | | 6 sec | | 4sec | | 11 seconds

Temporal relations and corresponding OCPN

Data Retrieving Engine

RTSM

Fast Forward operation

Pre- Fetch table Retrieval time = (Playback period *play rate) / Estimated BW + RDdelay

Model Global time

Model Fast Forward

Absolute time line The main deficiency in the absolute time line is the indeterminism of continuous objects. It might take more or less than 10 seconds for the audio file to play. – How to insure synchronization?

Indeterminism and absolute time line

Accessibility How to render a different type of media to the client? For example, a blind person do not need to download text files, instead he needs to convert it to audio format. Three cases: Converters on the Server. Converters on the Client. Converters with middleman server Cost function? Cost function?

Conclusion (This should go where we talk about extensions) Converting SMIL 2.0 to Petri-net for interoperability purposes. Timesheets use in SMIL2.0. User input into the Petri net model. Forward / Rewind / Pause in a PN model. Presenting Indeterminism and how to minimize desynchronization for uncontrollable objects in a PN model. Presenting both Spatial and temporal constraints in one Petri net model ( In progress) Accessibility