Alternative Text for Images [WCAG.PDF.01]
Test Basis (WCAG 2.0)
This test is based on the WCAG 2.0 Technique PDF1: Applying text alternatives to images with the Alt entry in PDF documents
Technique URL (WCAG 2.0)
Why this maybe a Barrier
Whenever an image is presented without an alternative text, it causes challenges for blind or vision impaired people who are unable to see the image. Any information conveyed in an image is lost to these users whenever a textual alternative is missing.
WCAG 1.0 Reference
1.1 "Provide a text equivalent for every non-text element (e.g., via "alt", "longdesc", or in element content). This includes: images, graphical representations of text (including symbols), image map regions, animations (e.g., animated GIFs), applets and programmatic objects, ascii art, frames, scripts, images used as list bullets, spacers, graphical buttons, sounds (played with or without user interaction), stand-alone audio files, audio tracks of video, and video. [Priority 1]"
WCAG 2.0 Reference
1.1.1 Non-text Content "“All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for the situations listed below. (Level A)"
- Controls, Input
- Time-Based Media
- Test
- Sensory
- CAPTCHA
- Decoration, Formatting, Invisible”