About Multimedia in HTML...
= Index DOT Html by Brian Wilson [bloo@blooberry.com] =

Justification of Multimedia in HTML

One of the biggest factors in the growth of the web has been the integration of multimedia capabilities within HTML documents. From the early versions of HTML, it has been possible to include image references in a document that would allow in-line placement. Recently, HTML has been extended to allow the embedding of sound, video, and VRML files as well. All of these capabilities now allow a very rich web surfing experience.

Ensuring Your Content is Conveyed as Intended

To be sure, not all browsers for HTML can support multimedia. This fact must also always be considered in HTML design. As the quantity and type of multimedia capability has grown in HTML, it has become ever more difficult to prevent the persistent slide of content on the web to being primarily multimedia based. Not to say this is a bad thing, but not EVERYONE can experience this capability. The reader may have a physical disability that may prevent the full effect to be experienced or the user may use a text-based browser. Authors must always remember that not ALL browsers or readers have the capability to experience the full intended multimedia experience that they try to deliver.

To this end, there are several methods available to help make multimedia content degrade well for browsers that can not support it. The IMG tag allows the inclusion of a text string that is only available when an image can not be loaded (whatever the reason.) The OBJECT tag also extends this a step further by allowing text representations of an Image Map to be displayed when the Image Map can not be used. These options should ALWAYS be used to ensure that your content is delivered in SOME fashion to the reader.

Delivering Multimedia In HTML

In-line Images, Movies, and VRML Worlds

[ Img ]

This is the grandpa multimedia tag. It was the first tag introduced to allow multimedia capability within documents. It also has the most extensions of any tag (about 20) which allow everything from the embedding of videos and VRML to a range of border, alignment and size properties.

Client Side Image Maps

[ Area, Map ]

This is a rather new method introduced by Spyglass that allows the browser to handle the transit decisions related to using image maps (hyperlinks defined by geometric regions of an image.) This process was previously handled by an external file that contained the geometric hyperlink definitions. The old method required an extra download request, and access to a server. The new method includes the information in the HTML page and is much faster.

Background Sounds

[ BGSound, Sound ]

These tags are analogous to the BACKGROUND attribute to the BODY tag. They allow the embedding of a sound that plays while a page is viewed. They are both extensions by different browser vendors that were created at approximately the same time. It is unlikely that either of these tags will make it into an HTML standard now that the OBJECT tag can absorb this functionality.

Multimedia Objects

[ Object ]

This is the new tag meant to absorb all of the functionality of the many disparate tags serving to include and process other multimedia content within an HTML document. This tag is meant to absorb and obsolete the Applet, Area, BGSound, Embed, Img, Map, and Sound tags.

Official References

ftp://ds.internic.net/rfc/rfc1866.txt

RFC 1866: The HTML 2.0 specification (plain text)

http://www.w3.org/pub/WWW/MarkUp/html-spec

The web version of the HTML 2.0 (RFC 1866) specification

http://www.w3.org/pub/WWW/MarkUp/Wilbur/

The HTML 3.2 (Wilbur) proposal
[Includes the APPLET tag and Client Side Image Maps]

http://www.w3.org/pub/WWW/MarkUp/Cougar/HTML.dtd

The experimental HTML (Cougar) draft
[Includes specifications for the OBJECT tag]

http://www.w3.org/pub/WWW/TR/WD-object.html

OBJECT: W3's Object draft specification.

ftp://ds.internic.net/rfc/rfc1980.txt

CSIM: RFC 1980 draft regarding Client-Side Image Maps

http://home.netscape.com/assist/net_sites/html_extensions.html

Netscape Extensions to HTML 2.0
[IMG: Details the many IMG tag extensions created for v1.1]

http://home.netscape.com/assist/net_sites/html_extensions_3.html

Netscape Extensions to HTML 3.0
[CSIM: Details Client Side Image Map tags]

http://www.microsoft.com/workshop/author/newhtml/htmlr020.htm

Internet Explorer 3.0 Tag reference
[BGSound: Includes description of BGSound, OBJECT, CSIM and IMG tag extensions.]

Tutorials

http://www.spyglass.com/techspec/tutorial/img_maps.html

CSIM: Spyglass' tutorial on Client Side Image Maps

http://www.iwaynet.net/~rtyler/htmltutorial/imagemaps.html

CSIM: Part of Ronda Tyler's 'Authoritative Guide to HTML'

Other Related Links

http://www.yahoo.com/Computers_and_Internet/Internet/World_Wide_Web/Page_Design_and_Layout/Icons

Yahoo's Image Icon link collection

http://www.yahoo.com/Computers_and_Internet/Multimedia/Pictures/Clip_Art

Yahoo's Image Clip-art link collection

http://www.yahoo.com/Computers_and_Internet/Internet/World_Wide_Web/Page_Design_and_Layout/Backgrounds

Yahoo's Background Image link collection

http://www.yahoo.com/Computers_and_Internet/Graphics/Computer_Animation/Animated_GIFs

Yahoo's Animated GIF link collection

http://www.yahoo.com/Computers_and_Internet/Internet/World_Wide_Web/Page_Design_and_Layout/Color_Information

Yahoo's list of resources on color in HTML documents