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Complex images

Complex images include things such as infographics, illustrations, charts and graphs. These kinds of images often need a text alternative that's too long to provide as image alt text.

Images that visually communicate relationships and concepts, and include text important for understanding that information, must use:

  • A short description in alt text.
  • A long description in adjacent text.

The short alt text description should follow the guidelines discussed in our advice on images, providing a brief, basic explanation of the image’s information. It must also name where the detailed description can be found, making sure to avoid sensory-specific language like 'left-hand paragraph' or 'blue box'.

The long description should be presented in text immediately adjacent to the image, such as the next paragraph. This should explain the image’s content in greater detail, potentially linking to a separate page with a full description if necessary.

For complex images used in learning and teaching materials, there may be pedagogical reasons why a full alt-text description cannot be provided. Examples of this may include when students are required to develop the skill of visually interpreting meaning from an image or graph. In such cases, the alt-text description should state “Please contact your module leader if you cannot visually access the information in this picture”. Reasonable adjustments to learning and teaching approaches for some disabled students may be required.

What and why: Alt text that describes an image isn't visible on a page but will be read by assistive technology, such as screen readers. However, extremely long alt text can pose some challenges for people.

If a short alt text description cannot communicate all the information in the image, a full description in nearby text allows people with visual impairments to receive the same level of detail as fully sighted users.

These descriptions should be such that no information would be lost if the image were removed from the page and substituted with the short and long descriptions.

Handwritten notes

Where possible, handwritten notes should be converted into electronic text (not scanned as an image), which will make them accessible to people using screen readers and potentially enhance readability for everyone.

This can be achieved in different ways, for example automatically using Optical Character Recognition (OCR) software, manually typed, or by audio-narrating the content and auto-captioning the resulting recording.

Microsoft Office Lens is available for Android and Apple iOS devices and can scan handwritten text and convert it to OCR.

The speech-to-text capabilities of Microsoft Office products may also be helpful, and most on-screen mobile device keyboards include an option to transcribe speech to text.

Please note, audio narration may be less effective for highly technical content including mathematical expressions.

If there is a pedagogic need for students to view handwritten content it can be provided alongside an accessible version covering the same learning content.

Colour contrast

You must ensure any text in a complex image meets contrast standards. Our guide on colour contrast explains what you need to know.