CIRCA:HTML5 & Multimedia

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HTML5

HTML5 is the new HTML specification currently being developed by the World Wide Web Consortium (W3C) and Web Hypertext Application Technology Working Group (WHATWG). Both W3C and WHATWG have working documents for the new specification (HTML5: A Vocabulary and Associated API’s for HTML and XHTML and HTML: Living Standard respectively) with the same definition of HTML5: The World Wide Web's markup language has always been HTML. HTML was primarily designed as a language for semantically describing scientific documents, although its general design and adaptations over the years have enabled it to be used to describe a number of other types of documents. The main area that has not been adequately addressed by HTML is a vague subject referred to as Web Applications. This specification attempts to rectify this, while at the same time updating the HTML specifications to address issues raised in the past few years. The WHATWG also has a visual representation of where HTML5 fits with the other specifications.

One major difference between HTML5 and the earlier specification is the addition of JavaScript API’s (Application Programing Interfaces). JavaScript is a client side scripting language having it as part of the HTML web page means that it is up to the browser to do something with it. (Devlin 2012)


Contents


History

Web & HTML

Tim Berners-Lee developed HTML and the world wide web in 1989 and in 1994 Berners-Lee founded the W3C, “a neutral organization designed to set standards for the web’s growth.” (Lambert 2005) Where one of the goals of W3C is to prevent one company from forcing a technology onto users, as Microsoft was trying to dominate the web from 1997 to 2007. (David 2010)

In 1998, W3C decided to stop developing HTML as they thought the future lay with XML and XHTML. As such, the web’s markup language remained at HTML 4.01 and the W3C went forward producing specifications for XHTML 1.0 and later 2.0. Meanwhile a new group was formed WHATWG, consisting of members from Opera, Mozilla and Apple. WHATWG started working on a specification called Web Applications 1.0 that would later be used for modelling HTML5. In 2006, W3C decided that further development of HTML was necessary and the latest version of XHTML would expire in 2009. Currently both W3C and WHATWG are working together on the new HTML specification known as HTML5. (Devlin 2012 and Lawson 2012)

Web & Multimedia

When the internet was created there was no multimedia and thus no standards for it. As time went on, internet users started putting images up online and these images started to become animated (GIFs). Video and audio files were large and connections slow, yielding an undesirable wait time for users. As internet connection speeds increased users were able to transfer files in shorter times (Lawson 2012) and we entered the age of the plugin.

Plugins, media players and codecs are terms that can be used interchangeably and they are used to play multimedia files. Plugins are specific to the file’s format and a user would need to download the right plugin in order to play multimedia on any given website ie. a webm file can only be read by a webm plugin.(Devlin 2012)

Some problems associated with plugins are; conflicting plugins and files would cause the browser to crash, constant downloading of plugins puts the computer at risk of also downloading malware and Apple’s 2010 announcement that there would be no support for Flash on iPads and iPhones posed a problem for mobile device users. (Devlin 2012)

HTML5 & Multimedia

HTML5 has audio and video elements written into it’s specification. This aspect of HTML5 is called native media where the multimedia is essentially built into the page. (Devlin 2012 and Lawson 2012) The benefits of native media are; speed, users browsers will be able to load web page faster

  • no need to download plugins
  • controls are provided by the browser
  • possible customization can be applied using JavaScript API’s
  • possible styling can be applied using CSS (Devlin 2012)

Audio Element

The audio element plays a sound or audio stream. (W3C 2012) An early requirement of HTML5 was that all browsers had to have built-in support for Ogg Vorbis audio files. The idea being that if you were using the HTML5 audio element then you would at least be able to play Ogg Vorbis files. However, Nokia and Apple disagreed with the requirement and it was dropped. (Devlin 2012 and Lawson 2012) Now different browsers decided to support different file formats as shown in Devlin’s figure Audio Formats and Browser Support.

Video Element

The video element is a media element whose media data is ostensibly video data, possible with associated audio data. (W3C 2012) Early requirements for HTML5’s video element was that all browsers needed to have built-in support for Theora Ogg video files. Again Nokia and Apple objected to this requirement and it was dropped from the specification. (Devlin 2012 and Lawson 2012) Like audio files, video files are supported by different browsers as shown in Devlin’s figure Video Formats and Browser Support.

Source: attribute & element

Both audio and video elements need something to tell the browser where the multimedia file is and this is where the source attribute comes in. The source attribute (src) gives the address of the that media file.

example of a simple audio element with source and autoplay attributes:
<audio src=”FileName.ogg” autoplay> </audio>
modeled after examples given by Devlin 2012

The source element allows the author to enter several different file type of the same video, the browser will only play the file type that it supports and ignore the others. This element creates slightly more work for the page authors but usage on the client side will be smoother. (Devlin 2012 and Lawson 2010)

example of a video using source element:
<video autoplay>
<source src="FileName.mp4" type="video/mp4">
<source src="FileName.webm" type="video/webm">
</video>
modeled after examples given by Devlin 2012

References

David, Mathew. 2010. HTML5: Designing Rich Internet Applications [Internet]. Burlington, MA : Focal Press [cited 2012 October 24] Available from:[1]

Devlin, Ian. 2012. HTML5 Multimedia:Development and Design [Internet]. Berkeley, CA : Peachpit Press [cited 2012 October 21] Available from: [2]

Lambert, Laura. 2005. The Internet: A Historical Encyclopedia [Internet]. Santa Barbara, Calif. : ABC-CLIO [cited 2012 October 19] 15V1-21V1. Available from: [3]

Lawson, Bruce. 2012. Introducing HTML5 [Internet]. Berkeley, CA : New Riders [cited 2012 October 21] Available from: [4]

[WHATWG]Web Hypertext Application Technology Working Group [Internet]. 2012. [Place of publication unknown]: HTML Living Standard [updated 2012 October 22; cited 2012 October 23] Available from: [5]

[W3C] World Wide Web Consortium [Internet]. 2012. [Place of publication unknown]: HTML5 A Vocabulary and Associated API’s for HTML and XHTML [Updated 2012 October 11; cited 2012 October 21] Available from: [6]

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