MULTIMEDIA

"Multimedia is the use of several different media to convey information (text, audio, graphics, animation, video, and interactivity)".(http://en.wikipedia.org/wiki/Multimedia)

Guidelines for using multimedia for the web

Multimedia is any combination of text, graphic, art, audio, animation, and video that can delivered via the web. While great multimedia interactivity can engage the audience, designers must be careful about using multimedia wisely. Elements for accessibility for consideration are

• Bandwidth - audio & video content requires large bandwidth if the files are huge. Knowledge and expertise is needed for preparing and compressing multimedia content
• While animation can add visual interest, excessing use can be annoying or distracting. Avoid repeated loops. (Williams & Tollett, p.98)
• Use of plug-ins - offer resources where the audience can download for the plug in required to view multimedia content
• Avoid annoying audio. Where there is audio content, offer the option of audio on/off button for the page

Examples of Multimedia Sites

• http://arseniphoto.com/ This is a multimedia site that utlizes Flash. White space is well utilized along woth colors and graphics. However, there should be an option of turning off audio programmed into the interface.
• http://muppets.go.com/ Muppets site - interactive launched today (11/19/2004)
• http://www.1800contacts.com/vision101/frames.html Great animated & interactive site for learning about vision

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GRAPHICS

Guidelines for using graphics or images for the web

The typical size screen monitor's resolution is 72dpi. When working on images set graphic measurements to PIXELS NOT inches

Always create web images at 72 dpi, using RGB color space, and preview images at 256 colors. (Most olderer computer systems has only 8-bit color cards)

When displaying images on monitors, browsers use a set of 216 colors called the browser safe colors. If the images on your page contain more than 216 colors in the browser safe palette, the browser will try to combine existing colors to reproduce the missing ones (a process called dithering). Thus producing an image that is not that sharp and clean.

The two types of image file formats that are most commonly used are JPEGs (Joint Photographic Experts Group) and GIFs (Graphic Interchange Format)
The GIF format can contain only 256 colors or less. Use GIFs for graphic formats in animation (Animated GIFS), transparency and interlacing.They are designed to graphics like logos and single colored images.
JPGS can contain millions of colors, therefore better for handling photographs or multicolored graphics.

Use the correct format of graphic types

Click here to review presentation of format types

Example of Bad use of Graphics

• Results of Saving in the wrong format
• File Size too large
• Bad background example - distracts reader from reading content on page, colors too bright
• Avoiding Halos & Artifacts (Williams & Tollet p.214-215)

Resources for Graphics/Images

• Photos - FreeFoto.com private non-commercial use on the Internet
• Public Domain - http://www.princetonol.com/groups/iad/links/clipart.html
  Extensive links for educators
• Wikipedia.Org http://en.wikipedia.org/wiki/Public_domain_image_resources

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Audio

Types of Sound files supported on the web

• MP3 (MPEG-Layer3: Motion Pictures Expert Group) - Best compression
• AIFF (Audio Interchange File Format) Standard Mac Format
• WAV (Waveform Audio file Format) - Developed by Windows & IBM
• MIDI (Musical Instrument Digital Interface)

Resources for Audio

• Flashkit.com -
  http://flashkit.com/soundfx/ Sound effects
  http://flashkit.com/loops/ Sound Loops

Video Reources

• Information about preparing video for the web

Animation

• Link to Animation Factory (Some are free to download)

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