8 Adding Media Objects Bringing content to SMIL presentations

8.1 SMIL and Media Content A SMIL presentation does not itself contain media Provides synchronisation of presentation to the user Media content refers to all the content that is seen or heard during a SMIL presentation: Images, video, animations, text, audio Each can be of many formats, depending on the capabilities of the SMIL client Images might be in GIF, JPEG, PNG or SVG formats Covered in the standard under: SMIL 2.0 Media Object Modules Similar to the Media Object Elements part of the SMIL 1.0 specification Module is implemented in both SMIL 1.0, 2.0 and XHTML+TIME clients Defines how content can be brought into a SMIL presentation Media are incorporated by making reference to them using elements

A SMIL presentation does not itself contain media

Provides synchronisation of presentation to the user

Media content refers to all the content that is seen or heard during a SMIL presentation:

Images, video, animations, text, audio

Each can be of many formats, depending on the capabilities of the SMIL client

Images might be in GIF, JPEG, PNG or SVG formats

Covered in the standard under: SMIL 2.0 Media Object Modules

Similar to the Media Object Elements part of the SMIL 1.0 specification

Module is implemented in both SMIL 1.0, 2.0 and XHTML+TIME clients

Defines how content can be brought into a SMIL presentation

Media are incorporated by making reference to them using elements

8.2 Referencing Media Elements Each piece of content requires a clip source element Elements are for the most part unary Become binary under some circumstances Give clip source elements a unique id Not mandatory but needed for timing and synchronisation src attribute defines the clip location using URI Location of clips can use a variety of protocols rtsp:// mms:// http:// file:// audio/hifi/… Media elements with different URIs can be mixed in a presentation Organise media content in folders Develop using local file based URIs Examples RealONE Internet Explorer v6 <video id=“ vid_id ” src=“rtsp:// server/path_to_video_file ” …/> <audio id=“ aud_id ” src=“http:// server/path_to_file ” … /> <img id=“ img_id ” src=“file://d: path_to_image_file ” … />

Each piece of content requires a clip source element

Elements are for the most part unary

Become binary under some circumstances

Give clip source elements a unique id

Not mandatory but needed for timing and synchronisation

src attribute defines the clip location using URI

Location of clips can use a variety of protocols

rtsp:// mms:// http:// file:// audio/hifi/…

Media elements with different URIs can be mixed in a presentation

Organise media content in folders

Develop using local file based URIs

Examples

RealONE

Internet Explorer v6

8.3 SMIL Content Element Tags QuickTIME IE v6: Defines a generic media clip <t:media/> Use <ref/> Defines a video element. <t:video/> <video/> Real: Defines streaming text (.rt) files Use XHTML and CSS <textstream/> Defines a lightweight media object Use XHTML and CSS <brush/> Real: Defines simple static text (.txt) files Use XHTML and CSS <text/> Generic clip type. Can be used in place of other elements <t:ref/> <ref/> Defines and image element such as a .GIF, .JPEG or .PNG file <t:img/> <img/> Defines an audio element. IE: Can also use <t:media/> <t:audio/> <audio/> Real: Animation clips such as Flash files. IE: Delineate animated GIFs <t:animation/> <animation/> Description IEv6 RealONE

8.4 Adding Text to Presentations Method differs according to the SMIL client Text handling is not part of the standard Timed Text Initiative is addressing representation of textual content RealONE player Use proprietary RealText ( .rt ) files Similar format to HTML Rudimentary and “fiddly” to use IE6 Uses HTML and Cascading Style Sheets QuickTime Use Text tracks Reference documentation Examples Using RealText

Method differs according to the SMIL client

Text handling is not part of the standard

Timed Text Initiative is addressing representation of textual content

RealONE player

Use proprietary RealText ( .rt ) files

Similar format to HTML

Rudimentary and “fiddly” to use

IE6

Uses HTML and Cascading Style Sheets

QuickTime

Use Text tracks

Reference documentation

Examples

Using RealText

8.5 Using Content Element Attributes Elements use attributes introduced in Timing and Synchronisation section Using metafiles with media src attribute Used for streamed audio and media Format depends upon streaming server implementation Examples: RealONE QuickTime Defining BASE URLs for clip src attribute Examples: RealONE Caching media content Dependent upon client caching RealONE has a media cache Default size and location Content needs to be cachable Internet Explorer v6 uses the browsers cache Streamed media is not cached in the client Files on the local file system are not cached

Elements use attributes introduced in Timing and Synchronisation section

Using metafiles with media src attribute

Used for streamed audio and media

Format depends upon streaming server implementation

Examples: RealONE QuickTime

Defining BASE URLs for clip src attribute

Examples: RealONE

Caching media content

Dependent upon client caching

RealONE has a media cache

Default size and location

Content needs to be cachable

Internet Explorer v6 uses the browsers cache

Streamed media is not cached in the client

Files on the local file system are not cached

8.6 Using the <brush/> element Explained in the SMIL Brush Media Module “ The brush element is a lightweight media object element which allows an author to paint a solid color or other pattern in place of a media object “ Implemented in RealONE player Regions can be filled with colour Apply the whole range of attributes available to other media objects Timing, transitions and animation Example RealONE [ 1 ] [ 2 ] <par> <brush id=“blu1” region=“ name_of_region ” color=“ colour_defnition ” begin=“” …/> </par>

Explained in the SMIL Brush Media Module

“ The brush element is a lightweight media object element which allows an author to paint a solid color or other pattern in place of a media object “

Implemented in RealONE player

Regions can be filled with colour

Apply the whole range of attributes available to other media objects

Timing, transitions and animation

Example

RealONE [ 1 ] [ 2 ]

8.7 Review SMIL defines a set of elements for including content in presentations Each item of content has to have an element Organise content types using a file system hierarchy /images /video /audio etc. Use the appropriate element for the media type For example: <img/> and <t:image/> Helps reading of the SMIL/XHTML+TIME file This rule can be broken! Using the <ref/> element [ RealONE ] Using the <t:ref/> element [ IE v6 ] Elements can refer to metafiles for streaming content Clients will cache some types of content Timing and synchronisation of content from previous section

SMIL defines a set of elements for including content in presentations

Each item of content has to have an element

Organise content types using a file system hierarchy

/images /video /audio etc.

Use the appropriate element for the media type

For example: <img/> and <t:image/>

Helps reading of the SMIL/XHTML+TIME file

This rule can be broken!

Using the <ref/> element [ RealONE ]

Using the <t:ref/> element [ IE v6 ]

Elements can refer to metafiles for streaming content

Clients will cache some types of content

Timing and synchronisation of content from previous section