SMIL ("smile"), the Synchronized Multimedia Integration Language, is a W3C recommended XML markup language for describing multimedia presentations. It defines markup for timing, layout, animations, visual transitions, and media embedding, among other things. SMIL allows the presentation of media items such as text, images, video, and audio, as well as links to other SMIL presentations, and files from multiple web servers. SMIL markup is written in XML, and has similarities to HTML.

Version history

As of 2008 the current W3C Recommendation for SMIL is SMIL 2.1.

SMIL 3.0

SMIL 3.0 was submitted as a W3C Working draft on December 21, 2006. The most recent revision was released on October 6, 2008.

SMIL 2.1

SMIL 2.1 became a W3C Recommendation in December 2005. SMIL 2.1 includes a small number of extensions based on practical experience gathered using SMIL in the Multimedia Messaging System on mobile phones.

SMIL 2.0

SMIL 2.0 became a W3C Recommendation in August 2001. SMIL 2.0 introduced a modular language structure that facilitated integration of SMIL semantics into other XML-based languages. Basic animation and timing modules were integrated into Scalable Vector Graphics (SVG) and the SMIL modules formed a basis for Timed-Text. The modular structure made it possible to define the standard SMIL language profile and the XHTML+SMIL language profile with common syntax and standard semantics.

SMIL 1.0

SMIL 1.0 became a W3C Recommendation in June 1998.

SMIL documents

A SMIL document is similar in structure to an HTML document in that they are typically divided between an optional section and a required section. The section contains layout and metadata information. The section contains the timing information, and is generally composed of combinations of two main tags - parallel ("") and sequential (""). SMIL refers to media objects by URLs, allowing them to be shared between presentations and stored on different servers for load balancing. The language can also associate different media objects with different bandwidth requirements.

File extension

SMIL files take either a .smi or .smil file extension. However, SAMI files also use .smi, which creates some ambiguity at first glance. As a result, SMIL files commonly use the .smil file extension to avoid confusion.

Status of SMIL

SMIL is being implemented on handheld and mobile devices and has also spawned the subset known as Multimedia Messaging Service (MMS) which is a video and picture equivalent of SMS. MMS is also jokingly called "Mini-Me SMIL" by multimedia technicians in the mobile content industry.

SMIL is also one of the underlying technologies used by HD DVD for advanced interactivity.

SMIL player software

• AMBULANT
• Helix Player
• QuickTime Player
• RealPlayer
• Totem
• KMPlayer
• Windows Media Player (Playlist Files)
• Zune (Playlist Files)

Sources

• van der Heijden, Dennis "SMIL Standards and Microsoft Internet Explorer 6, 7, and 8". Axistive, Retrieved on 2007-12-22.

See also

• Synchronized Accessible Media Interchange (SAMI)
• HTML+TIME, XHTML+SMIL
• MMS - MMS is a subset of SMIL for mobile telephone multimedia messaging
• SVG - Scalable Vector Graphics (MIME type: image/svg+xml )- an open standard XML vocabulary for vector graphics which can integrate with SMIL
• Timed-Text - a W3C standard for synchronized captioning.
• National Research Institute for Mathematics and Computer Science (Centrum voor Wiskunde en Informatica, CWI) - Research Institute in the Netherlands with a focus on SMIL
• NCL - Nested Context Language
• Semantic Web
• SmilScript
• FakeSmile - JavaScript library to emulate SMIL functionality in browsers

External links

• W3C's SMIL Web Site
• SMIL 2.1 (W3C Recommendation)
• Apple QuickTime SMIL
• SMIL tutorial
• W3Schools SMIL Tutorial