© De Montfort University, Synchronised Presentations using Windows Media Howell Istance School of Computing De Montfort University

© De Montfort University, History 1 st version of media player shipped with Windows 3.0 Win95 – Media Player – playback of small AVI and MPEG movies Windows Media Player version 6.1 shipped with Windows 98 (can now play MP3 audio) Windows Media Player 7 – shipped with ME, supplemented with media organisation capabilties Windows Media 9 series – September 2002, latest release of MPXP (media player for XP) – which runs on 2000 and ME,as well as XP

© De Montfort University, Windows Media 9 series Windows Media Services 9 - will ship (only) as part of Windows.NET Server Windows Media Series 9 Codecs - new audio and video codecs Windows Media Player 9 - new Windows Media Player that runs on various Windows OSes, Windows Media Encoder 9 Windows Media 9 Digital Rights Management (DRM) - enables secure digital media solutions on top of the Windows Media 9 Series platform. Windows Media 9 Software Development Kit (SDK) – SPI to embed Windows Media 9 Series components in applications.

© De Montfort University, Source: microsoft media 9 series whitepaper

© De Montfort University, Audio and Video Enhancements claimed by Microsoft Digital 5.1 Surround Sound Codec for streaming or download-and-play, at bit rates as low as 128 Kbps. Lossless Audio Compression capable of compressing CD audio without loss into one-half to one-third of its original size high-definition video quality, supporting video frame sizes of 1280 x 720 pixels (720p) with software decoding

© De Montfort University, Enhancements claimed for playback Instant-On/Always-On Streaming: Content streams to the player’s cache as fast as the network will allow Intelligent Streaming Features – Multiple Bit Rate and Multiple Language Support – Variable Speed Playback – “Users can save time and improve comprehension by easily speeding up or slowing down playback of audio and video content without changing the pitch and tone of the original audio” (

© De Montfort University, Approaches to synchronised presentations Nothing in Microsoft Whitepaper about changes to this Embedding synchronisation commands into the encoded (ASF) media file –Uses Windows On Demand Producer, proprietary MS technique HTML+Time –Only supported by IE –Proposed standard, not endorsed by W3C (afaik) but supported by Microsoft

© De Montfort University, File types ASF files (Advanced Streaming Format) are media files (.AVI) encoded in streaming format by Windows Media Encoder –may also include slide shows and synchronizing events. –Can reside on several server types WindowsMedia Services Server. File names will start with mms://. HTTP Server. File names will start with Local or network drive. File names will start with file://. ASX files are text files which manage streaming of ASF files –Contain no data, only instructions, comparable to SMIL files –always sit on an HTTP server

© De Montfort University, HTML+TIME Additional attributes are introduced for every document element that can appear in the body of an HTML document Attributes include begin, end and dur Here is the content of the start paragraph This appears 10 seconds after the start paragraph Start of time reference specified by BeginWith=id Seq implemented as additional HTML element rather than an attribute

© De Montfort University, Encoding events into media stream Windows Media wraps all media elements into one ASF file, similar to Shockwave Flash movies (according to Microsoft) any object can be placed into an ASF data stream, including audio, video, scripts, ActiveX controls and HTML documents Less flexibility for updating content, but more stable client-side playback Requires proprietary tool – WODP, free lightweight version of Sonic Foundry’s video producer

© De Montfort University, Windows on-demand producer

© De Montfort University, Commands Essentially scripts adding to the time line of the encoded media To add urls containing html files to a soundtrack, specify command type as url, and the time to insert Example of a slide show where html documents represent slides to be shown at specified times after the start of an audio track

© De Montfort University, Entering Commands….

© De Montfort University, Other command types.. text – displays text in the captioning window of the Windows Media Player beneath audio/video region WMClosedCaption – similar to Text, accessibility feature for hearing impaired WMTextBodytext – displays text to the right of the audio video area WMTextHeadline – displays text in bold, above audio/video area

© De Montfort University, Markers…. Can be inserted into the audio or video timeline Enables user to jump to specific points in the timeline, markers appear in the playlist, similar to CD playlist

© De Montfort University, Publishing the presentation… WODP creates a ‘redirection’ file with extension.wax, similar to a RealSystems.ram file – directs the player to the url of the.asf file on the Windows Media server Uses a collection of templates to generate html pages –url flip (slide show) –Simple embedded player – embed a WMP in a web page –Simple stand alone player – creates a page with a link which launches the player –Table of Contents – creates links to markers defined in the asf file