SMIL 2.0 — Interactive Multimedia on the Web

Lloyd Rutledge

Multimedia and Human-Computer Interaction Group
CWI, Amsterdam, The Netherlands
W3C SYMM working group

Lynda Hardman, Jacco van Ossenbruggen: CWI
Dick Bulterman, Jack Jansen, Sjoerd Mullender: Oratrix
W3C SYMM working group

Synchronized Multimedia Integration Language (SMIL)

Main Points

Pronounced smile

Multimedia for the Web — for multimedia what HTML is for hypertext

Integration format for presentable mono-medium formats

Structure

SMIL 1.0 — W3C Recommendation in 1998

SMIL 2.0 "meta-language" W3C Recommendation in 2001

SMIL 2.0 family formats SMIL Profile and SMIL Basic released with SMIL 2.0

SMIL 2.0 family format XHTML+SMIL lingers unstandardized

Timed Text just made a recommendation last month!

Main Themes

Powerful timing and synchronization

Adaptive to users and systems

Models a flexible but consistent presentation and user interface

SMIL Isn't Flash

Open and Integrable Syntax

Adaptive, especially for the disabled

SMIL 2.0 Profiles

What is a Profile?

A language for which a browser can be built

A combination of modules from the SMIL 2.0 "meta-language"

Possibly non-SMIL constructs with SMIL constructs

SMIL 2.0 Language Profile (SMIL Profile)

What is typically thought of as SMIL 2.0

Most of SMIL 2.0 features in one profile

SMIL 2.0 Basic Language Profile (SMIL Basic)

Intented for mobile devices, assumes restricted processing ability

Much behind-the-scenes use with 3GPP and MMS

XHTML+SMIL

Applies timing to text-based display

XHMTL-based layout

SMIL 1.0

Backwards-compatable — can be played on SMIL Profile browsers

Timed Text

Timing of text display, especially for captions

SMIL Implementors

Image 1

CWI

Ambulant player — Updated for SMIL 2.1 (from end 2005)

University of Finland

X-Smiles — SMIL and other XML in one format

Real

RealOne for SMIL 2.0

Adobe

Adobe's SVG Viewer supports SMIL animation in SVG

Oratrix

GRiNS player and editor

Support for all profiles

Microsoft

Internet Explorer 5.5 and up plays XHMTL+SMIL

Apple

QuickTime 4.1 and up supports SMIL 1.0

Many Research and Student Projects

What We Need to Specify

Media

Adaptivity

Layout

Interaction

Timing

Basic Media Integration

Media Integration

The Waag is a medieval buiding in Amsterdam The Waag is a medieval buiding in Amsterdam. It was originally a gate into the city through the city wall. Later it became a weighhouse for goods being brought
<text> <image> <video> <audio> <animation> <textstream>

Media Typing

The mimetype Construct

Communicating mimetypes through HTTP

Filename suffixes

The type= Attribute

Brush Media — Draw a rectangle on the screen

The <brush> Element

The color= Attribute

Mostly replicable with <region>

The <region> Element

Each media object instance contains a region reference:

allows author to know where object will be played

<video src="anchor.mpg" region="V-main"/>

The region is defined by:

A regionName= or id= attribute for each region is required

Region positioning attributes

Length values are percentage values or pixels

The unit "px" may be omitted

The z-index gives the stacking order (highest integer stacks on top)

The soundLevel= attribute

Sub-regions — Precise Image Positioning within Regions

Region Positioning Attributes

Image 14

Which time?

Types of time:

media item time axis

video divided in frames, audio sampled at 44kHz

Image 18

document time

image starts at certain time and ends at a later time

Image 19

run-time presentation

video data bits get caught up in network, so end time is delayed

Image 20

Types of Time

Types of time on example time bar

Content Control Issues

Adaptation for User

Disabilities

Language

Previous knowledge

Adaptation for Environment

Delays: bandwidth, available CPU time

Available processing: media peripherals, browser additional features

Adaptation for Document Purpose

Selection of appropriate content

Media items have different meanings in different focus

Progression of presentation to meet purpose

Specifying Content Control

Selectivity on All Elements

Each element must pass a "playability" test

Those not selected are ignored and not played

<switch> Element

At most one of the children of a switch element is played

The first acceptable element is chosen, so ordering should be best first

Works on anything the browser wants

System Test Attributes

Standard collection of conditions to test for for selectivity

Test attributes can be combined

Custom Test Attributes

Anyone can define adaptive test attributes for use in SMIL

Won't be recognized by all browsers

Potential examples — knowledge level, audience profile, length of time

System Test Attributes

Adaptation to User

The systemLanguage= Attribute

The systemCaptions= Attribute

The systemOverdubOrSubtitle= Attribute

The systemAudioDesc= Attribute

Adaptation to Hardware

The systemBitrate= Attribute

The systemCPU= Attribute

The systemScreenSize= Attribute

The systemScreenDepth= Attribute

Adaptation to Software

The systemOperatingSystem = Attribute

The systemComponent= Attribute

The systemRequired= Attribute

Basic Linking Construct Overview

The <a> Element and href= Attribute

The <a> Element

The href= Attribute

Linking within SMIL Presentations

The href="#" Attribute Assignment

Play Spaces for the Link Destination

The show= Attribute

The external= Attribute — open with external program

The target= Attribute — region or other display space to show in

Play States

The sourcePlaystate= Attribute

The destinationPlaystate= Attribute

Sound

The sourceLevel= Attribute

The destinationLevel= Attribute

The <transition> Element — Defining Transitions for Use

The <transition> Element

In document head

Defines one transition for use in presentation

Types of Transitions

The type= Attribute — Which of the fixed set of transition types to use

The subtype= Attribute

Some transition types have subtypes

Such as type ="barWipe" with subtypes ="leftToRight" and ="topToBottom"

Controlling the Transition

The direction= Attribute — ="forward" (default) or ="reverse"

The fadeColor= Attribute — color value for what is faded from/to

The startProgress= and endProgress= Attributes

How far through default transition to start/end

Transition Modifiers

The horzRepeat= and vertRepeat= Attributes

Repeating the transition in each direction

The borderColor= and borderWidth= Attributes

Changing the appearance of wipe borders

Animation

Animation Elements

The <animate> Element — change an attribute value over time

The <animateMotion> Element — move an object across the screen

The <animateColor> Element — change an object's color

The <set> Element — assign an attribute a value for a period of time

Specifying the Animation Target

The href= or targetElement= Attribute — ID element with attribute to animate

The attributeName= Attribute

The attributeType= Attribute — ="XML", ="CSS", or ="auto"matically determine which

Listing the Animation Values

The from= and to= Attributes — starting and ending values of attribute in animation

The by= Attribute — incremental value change

The values= Attribute — list of values the attribute goes through

miniFiets 2.0 — The Layout

<!DOCTYPE smil PUBLIC "-//W3C//DTD SMIL 2.0//EN"
			"http://www.w3.org/TR/REC-smil/SMIL20.dtd">
  <smil xmlns="http://www.w3.org/2001/SMIL20/Language">
   <head>
    <layout>
     <topLayout title="Fiets Amsterdam Tour"
		backgroundColor="black" width="1010" height="665">
      <region regionname="splashScreen"  top="5" left="5" bottom="5" right="5"/>
      <region regionname="buildingImage" top="5" right="5" width="875" height="655"/>
      <region regionname="closedCaptioning" bottom="5" left="5" right="5" height="60"/>
      <region title="Thumbnail Bar" top="5" left="5" bottom="5" width="120">
       <region regionname="museumThumb"     fit="meet" height="90" top="65"/>
       <region regionname="weighhouseThumb" fit="meet" height="90" top="280"/>
       <region regionname="CWI-INSThumb"    fit="meet" height="90" top="495"/>
      </region>
     </topLayout>
    </layout>
    <transition id="fade1s" type="fade" dur="1s" />
   </head>
    
Color Key
Media Content
Layout
Timing
Linking
Adaptivity

miniFiets 2.0 — The Greeting Section

   <body>
    <seq>
     <par title="Greeting Section" end="greet.end+1s">
      <img src="FietsLogo.jpg" region="splashScreen" end="greet.end"
	 transin="fade1s" transout="fade1s" alt="Logo for Fiets: a bicycle zone sign"/>
      <par id="greet" begin="1s">
       <switch>
	<par systemlanguage="en">
	 <audio src="welcome.wav"  region="buildingImage"
		alt="Welcome to Fiets, your self-guided tour of Amsterdam (spoken)" />
	 <text  src="welcome.html" region="closedCaptioning" systemcaptions="on"
		alt="Welcome to Fiets, your self-guided tour of Amsterdam (captions)"/>
	</par>
	<par systemlanguage="nl">
	 <audio src="welkom.wav"  region="buildingImage"
		alt="Welkom bij Fiets, uw eigen stadswandeling door Amsterdam (gesproken)"/>
	 <text  src="welkom.html" region="closedCaptioning" systemcaptions="on"
	      alt="Welkom bij Fiets, uw eigen stadswandeling door Amsterdam (ondertiteling)"/>
	</par>
       </switch>
      </par>
     </par>
Color Key
Media Content
Layout
Timing
Linking
Adaptivity

miniFiets 2.0 — The Thumbnail Section

   <par title="Thumbnail Section" dur="indefinite">
      <par>
       <a href="#museum"     alt="Show the Rijksmuseum">
	<img src="museum.jpg"     region="museumThumb"     alt="Rijksmuseum thumbnail"/>
       </a>
       <a href="#weighhouse" alt="Show the Weighhouse">
	<img src="weighhouse.jpg" region="weighhouseThumb" alt="Weighhouse (Waag) thumbnail"/>
       </a>
       <a href="#CWI-INS"    alt="Show the CWI-INS building">
	<img src="CWI-INS.jpg"    region="CWI-INSThumb"    alt="CWI-INS building thumbnail"/>
       </a>
      </par>
      <excl dur="indefinite">
       <img src="museum.jpg"       id="museum"
	    region="buildingImage" alt="Rijksmuseum"      />
       <img src="weighhouse.jpg"   id="weighhouse"
	    region="buildingImage" alt="Weighhouse (Waag)"/>
       <img src="CWI-INS.jpg"      id="CWI-INS"
	    region="buildingImage" alt="CWI-INS building" />
      </excl>
     </par>
    </seq>
   </body>
  </smil>
    
Color Key
Media Content
Layout
Timing
Linking
Adaptivity