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Discover the importance of text equivalents for images to improve website accessibility, with insights on text rendering, types of images, and detailed findings from an Australian university website audit. Learn why the lack of knowledge and QA processes hinder accessibility progress.
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Ausweb 07 Australian university website accessibility revisited Dey AlexanderScott Rippon
Summary of paper • Accessibility audit done in 2003 • 98% sites not accessible • Looked at 4 pages from 41 university websites • 100% sites not accessible • 135 of 164 pages were not WCAG 1.0 level-A conformant • Failures against 7 of 17 priority one checkpoints • Most failures against checkpoint 1.1 – text equivalents • Most problems with text equivalents for images
Who uses text equivalents for images? • Blind users • Use screen reader or text browser with speech output • Hear the text alternative for an image read out • People who use a text browser • Prefer it for a range of reasons • People who use a graphical browser with images turned off • Usually related to bandwidth issues
“Text equivalent” – both words are important • "Text" important because • It can be read/displayed by all user agents • graphical browsers • text browsers • voice browsers and screenreaders • braille readers • handhelds
“Text equivalent” – both words are important • "Equivalent" is important because • Any old text alternative will not do • Must fulfill the same purpose or function of the original content • Must provide an equivalent experience for the end user
Two main types of images • Contain content • Text rendered as an image • Text on photos, etc • Logos and taglines • Decorative or layout • Set a mood • Help tables/pixel-based layouts work
Text equivalents for decorative images • Consider the function, then think of how to make the experience equivalent • For someone interacting within a non-graphical environment, decoration and layout are irrelevant, so • Leave ALT attribute blank, but • Don’t leave it out of the IMG element <img src=“students-smiling.jpg” alt=“”>
Text equivalents for content images • Consider the function, then think of how to make the experience equivalent • Text displayed as an image • Function: the message in the text • Navigation buttons • Function: tells you what’s on the linked page • University logo • Function: tells you which site you’re on
Detailed findings online www.deyalexander.com.au/publications/ausweb07
For discussion later? • Why does this problem persist? • Lack of knowledge? • Don’t know about text alternatives • Don’t know who they’re for, how they’re used • Don’t care? • Not enough time to do web stuff anyway • “We don’t have any blind users” • Don’t check? • No QA process for basic accessibility