Web Team: Contribute Resource Guide
Image and Multimedia Guidelines
Digital media can enhance the delivery of Web-based content. Current software programs allow the creation of projects in a wide variety of formats, including: audio-only, audio-narrated presentations, photo slideshows, and Web-based video. The three main issues concern accessibility, bandwidth and copyrights.
Accessibility
Section 508 requires that Web-based media files meet accessibility standards. Audio-only files must be accompanied by text transcripts. Video files must have synchronized captions, along with a text-only transcript of the audio portion. Captioning can be done manually or by hiring an outside company at a reasonable rate. More information can be found at:
Bandwidth
Available bandwidth and bandwidth consumption are important considerations for Web-based digital media projects. Many factors affect available bandwidth, including: internet congestion during peak usage times and client connection speed (dial-up, cable modem, DSL, T1). Bandwidth consumption should also be carefully considered; over-use of media files should be avoided. Also, low-bandwidth alternatives should be considered when possible (i.e. using audio-only for talking head interviews and reserving video for demonstration purposes; using streaming media solutions instead of downloadable audio/video; reading from prepared scripts for audio-narrated presentations to ensure they are concise.)
To determine how large a file is, double click on My Computer, browse to the folder on your PC where the file is saved, and look at the Size column. The lower the number, the smaller the size and the quicker it will download.
For example, using a dial-up modem, a 43MB (about 44,000KB) PowerPoint file would take an average of 1 hour and 48 minutes to download. On a high speed internet connection (T1 line) it would download in 4 minutes 5 seconds.
A visitor may be willing to wait several seconds to view an image or a multimedia file, but not much longer than that. If you have large files that take a long time to download, your visitor will move on to another site, and you’ve lost an opportunity to educate or inform them.
Copyright
It is important to remember that copyright laws apply to all audio, video and photographs used in your digital media productions. Written permission must be obtained from original author(s) of all content before it can be included in a media project. For example: popular music files are copyright protected, even if a downloadable version was located on the Web; music CD’s are copyright protected, even if the CD was purchased. The same is true for photographs available on the Web and television programs recorded onto VHS or DVD.
For more information, please refer to the Regents Guide to Copyright and Fair Use located at: http://www.ctl.uga.edu/teach_asst/copyright.htm
Delivery Methods
Consider your audience when adding images or multimedia projects to your Web site and think in terms of what visitors might want to accomplish or want to see. For instance:
- A few well-chosen and properly formatted images from an event may be more effective than several random images not formatted at all. Formatting images can be accomplished through image editing software like PhotoShop, PaintShop Pro or PhotoFiltre.
Adobe tutorial: Converting Images to Successful Web Graphics.
http://www.adobe.com/devnet/contribute/articles/convert_images.html - A large, image-intense PowerPoint presentation file can be compressed without any appreciable loss of quality and it will download quicker.
Microsoft tutorial: Reduce the Size of Your PowerPoint Files
http://office.microsoft.com/en-us/powerpoint/HA011168821033.aspx - Full text reports or bulletins can be saved as printable PDF files instead of inserting all the content into a new Web page.
Microsoft Word tutorial: Convert Documents Between Word and PDF
http://office.microsoft.com/en-us/word/HA011683331033.aspx
Image Formats
Use images that convey information or enhance your site’s design. Don’t use images just because you can. Ask yourself why an image is there. If it's not adding anything to a page, consider removing it.
Photographic images, whether from a digital camera or a scanner, should be saved in JPG format. Since images on a Web site are meant to be viewed, the quality does not have to be as high as for printing. A resolution setting of 72 pixels/inch or a compression ratio of 40-50 is acceptable. Check your user manual for your digital camera or scanner for more information on setting resolution.
Clip art or line art, buttons, bullets and icons are generally saved as GIF files. Reducing the number of colors in a GIF image may help reduce the file size.
All images should have descriptive ALT tags assigned to them.