In Part I one of this series, I looked at writing semantic HTML and ARIA attributes to take image accessibility well beyond the limitations of the alt attribute. Presenting images with text-based descriptions and enhancements that serve all users is an essential foundation for image accessibility. That foundation must be in place before pursuing any of the techniques in this post, which looks at the limitations of the src attribute for accessibly delivering images in an era of responsive web design. To make images themselves accessible requires delivering a crisp, high-fidelity image that best suits the device and preferences of…
Author: Karl Stolley
Karl Stolley
Karl Stolley is Associate Professor of Digital Writing & Rhetoric at Illinois Institute of Technology in Chicago, IL. He's on Twitter @karlstolley and GitHub and maintains a web presence at https://karlstolley.com/
The alt attribute is the HTML feature most often associated with accessibility. It’s been around since the HTML 2.0 specification (RFC 1866, finalized in 1995), which noted that “user agents may process the value of the ALT attribute as an alternative to processing the image resource indicated by the SRC attribute.” In plain English, alt attributes were meant as fallback content for web browsers unable to display images, which not all early web browsers could. The World Wide Web Consortium formalized alt as an accessibility feature four years later, in May 1999’s Web Content Accessibility Guidelines 1.0 specification. The attribute…