W3C Issues First Public Draft of Synchronized Multimedia Integration Language (SMIL)

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Key Industry Players and Research Organisations Team-Up to Merge the Web with Television



SOPHIA-ANTIPOLIS, FRANCE -- 6 November, 1997 -- The World Wide Web Consortium (W3C) today announced the first public working draft of Synchronized Multimedia Integration Language (SMIL; pronounced "smile"). SMIL enables authors to bring television-like content to the Web, avoiding the limitations of traditional television and significantly lowering the bandwidth requirements for transmitting this type of content over the Internet. With SMIL, producing audio-visual content is easy; it does not require learning a programming language and can be done using a simple text editor.

SMIL was developed by the W3C Synchronized Multimedia (SYMM) Working Group, a unique mix of experts from the four divergent industries (CD-ROM, Interactive Television, Web, and audio/video streaming) interested in bringing synchronized multimedia to the Web. The W3C SYMM Working Group includes both key industry players such as Digital Equipment Corporation, Lucent/Bell Labs, Microsoft, Netscape, Philips, RealNetworks and The Productivity Works, and leading research organisations such as Columbia University, CWI and INRIA.

"The release of SMIL demonstrates that despite their different backgrounds, these people are willing to agree on a common format," said Philipp Hoschka, Chair of the W3C SYMM Working Group and Editor of the SMIL specification. "Such an agreement is the necessary signal for content providers to start creating synchronized multimedia content for the Web, and, thus, a prerequisite for market growth in this area".

Powerful Features

SMIL offers the following key features:

  • Easy-to-learn synchronization primitives: 90% of the power of SMIL can be tapped by mastering only two tags, "parallel" and "sequential".
  • Temporal hyperlinking: Offers all the capabilities of hyperlinks in HTML, and adds capabilities required in time-based presentations.
  • Reusability of Media Objects: All components of the multimedia presentation are referenced via URLs rather than physically embedded into SMIL file. For example, videos stored in a digital video library can be reused in many presentations.
  • Load balancing: Different media objects in a presentation can be stored on different servers -- another benefit of using URLs rather than physically including media objects within the SMIL document.
  • Language selection: Authors can indicate that an audio track is available in several languages, thus increasing the potential audience of the content.
  • Bandwidth selection: Authors can express that a media object such as an audio track is available in different versions, each having been encoded for a different transmission bandwidth. This guarantees that presentations can be played even when only low-bandwidth access is available.

Television and the Web

In a typical television news broadcast, large parts of the screen contain text, still images and graphical elements, with full-motion video occupying only a small part of the screen real estate. These media types can all be included on a Web page today. However, the Web lacks a simple way to express synchronization over time, for example, "play audio file A in parallel with video file B" or "show image C after audio file A has finished playing". SMIL enables this type of information to be expressed quite easily, allowing television-like content to be created on the Web.

When rewritten in SMIL, many of today's television news broadcasts would require far less bandwidth, eliminating the need to convert low-bandwidth media types such as text and images into high-bandwidth video. "SMIL avoids having to swamp the Internet with high-bandwidth video if you want to create television-like content," explained Hoschka.

Of course, the Web offers far more than just television. For example, a search engine can be used to find a particular SMIL presentation. As the Web is inherently interactive, users can follow links embedded into a SMIL presentation to obtain background information on a newscast, or to an order form for a product described in a commercial. "Users can switch from 'couch-potato' mode into interactive mode with a simple mouse click" said Hoschka.

Ease of Authoring

Today, few authors write synchronized multimedia presentations for the Web because existing approaches have serious drawbacks. Current approaches require the use of an expensive authoring tool or to learn programming.

SMIL removes these drawbacks. SMIL documents can be authored using a simple text editor, following the success model of HTML. Moreover, authors can describe a presentation using three simple XML elements instead of having to learn a complex scripting language. "SMIL will have the same effect for synchronized multimedia as HTML had for hypertext," predicts Hoschka. "It will bring synchronized multimedia authoring to the masses."

The SMIL specification has been produced as part of the W3C Synchronized Multimedia Activity. After a period of public and Member review, W3C expects SMIL to be endorsed as a new W3C Recommendation.

Please see attached testimonials document for additional information on SMIL. Further information on SMIL is available at http://www.w3.org/AudioVideo/


About the World Wide Web Consortium [W3C]

The W3C was created to develop common protocols that enhance the interoperability and promote the evolution of the World Wide Web. It is an industry consortium jointly run by the MIT Laboratory for Computer Science (LCS) in the USA, the National Institute for Research in Computer Science and Control (INRIA) in France and Keio University in Japan. Services provided by the Consortium include: a repository of information about the World Wide Web for developers and users; reference code implementations to embody and promote standards; and various prototype and sample applications to demonstrate use of new technology. To date, over 220 organizations are Members of the Consortium.

For more information about the World Wide Web Consortium, see http://www.w3.org/

About the MIT Laboratory for Computer Science

Now in its third decade, MIT LCS is dedicated to the invention, development and understanding of information technologies expected to drive substantial technical and socio-economic change. The LCS has helped information technology grow from a mere curiosity to 10 percent of the industrial world's economies by its pioneering efforts in interactive computing, computer networking, distributed systems and public key cryptography. LCS members and alumni have started some thirty companies and have pioneered the Nubus, the X-Window System, the RSA algorithm, the Ethernet and spreadsheets.

For more information about the MIT Laboratory for Computer Science, see http://www.lcs.mit.edu/


INRIA, the French National Institute for Research in Computer Science and Control, is a public-sector scientific institute charged with conducting both fundamental and applied research, and with transferring research results to industry. INRIA is made up of five Research Units located at Rocquencourt (near Paris), Rennes, Sophia Antipolis, Nancy and Grenoble. Areas of current research include information processing, advanced high speed networking, structured documents, and scientific computation.

For more information about INRIA, see http://www.inria.fr/

About Keio University

Keio University is one of Japan's foremost computer science research centers and universities. It is one of the oldest private universities in Japan, and has five major campuses around Tokyo. Keio University has been promoting joint research projects in cooperation with industry, government and international organizations, and is now becoming one of the research leaders for the network and digital media technology.

For more information on Keio University, see http://www.keio.ac.jp/


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"SMIL is the first non-proprietary synchronized multimedia integration format available for the Web -- or anywhere else, for that matter. It is an important first step in moving declarative multimedia specification technology from research environments to the user community. As such, it will allow the development of complex multimedia presentations without requiring user-level programming of multimedia interactions.

-- Dr. Dick Bulterman, Head, Multimedia and HCI at CWI in Amsterdam, The Netherlands and technical director of the CHAMELEON Adaptive Multimedia Authoring project (ESPRIT 20594)


"Synchronized Multimedia Integration Language (SMIL) introduces for the first time Web-based hypermedia presentations that are truly dynamic in nature. Its time-based document structure and relation-based temporal model make SMIL perfect for multimedia authoring, even for users of simple text editors"

-- Jin Yu, Research Staff Member at Digital Equipment Corporation's Palo Alto-based Systems Research Center


"SMIL is a major step toward a seamless integration of the Web and Interactive television technologies. The doors are now open to a new and truly multimedia universe of information. SMIL is simple but very powerful thanks to its underlying temporal model."

-- Dr. Nabil Layaida, Research Fellow at INRIA Rhone-Alpes in Grenoble


"Multimedia creation and presentation on the Web will eventually be as commonplace as e-mail is today. SMIL provides a universal language for authoring multimedia which allows users to take greater advantage of network infrastructures and multimedia computers without having to learn vast amounts of programming information. The era of truly dynamic multimedia is about to arrive."

-- Sid Ahuja, Director of the Multimedia Communications Research Laboratory at Bell Labs, the Research and Development Arm of Lucent Technologies


"SMIL is a great file format for linking multimedia creation tools to RTSP-based streaming media systems. RealNetworks supports the W3C's SMIL proposal, which is rallying the Internet multimedia community around quality open standards."

-- Philip Rosedale, Vice President, Media Systems Group, RealNetworks

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