Images of Text
Images of text are inaccessible to a variety of people with disabilities. Images of text include scanned PDFs, photos of text, or screenshots of text. Readers cannot adjust the size, color, alignment, or spacing of text contained in an image, which can significantly impact the readability of the document for people with certain cognitive or visual disabilities. Additionally, some screen readers and text-to-speech software cannot detect text contained in an image, which means any text contained in an image is inaccessible to people using those tools.
In order to make an image of text accessible, you will need to convert it into digital text. Digital text can be selected, copied, or modified, which benefits readers who need to adjust the visual appearance of the text for accessibility purposes. It can also be enlarged without resulting in any loss in clarity, which is important for people with low vision. Digital text can also be read by assistive technology.
This isn’t to say that digital text alone makes a document fully accessible. In most cases, there is more work needed to make an electronic document fully accessible, but converting images of text to digital text is a great start.
Converting Images of Text
To convert an image of text to digital text, you can use optical character recognition (OCR) software. OCR software uses a computer algorithm to convert images of text into digital text. CU Boulder offers SensusAccess as a free OCR service to campus. Google Drive and Microsoft OneNote also provide free built-in OCR tools.
SensusAccess is a web-based document conversion program that provides a variety of accessibility conversion services, including changing images of text into digital text. It is available to all CU Boulder employees and students. To convert a file to digital text using SensusAccess, follow our SensusAccess file conversion tutorial.
Because OCR conversion is conducted by software, the converted text may not be 100% accurate. It is important after using OCR to check over your content and fix any errors resulting from the conversion. If you need to edit the text in a PDF, CU Boulder faculty and staff can download Adobe Acrobat Pro at no cost.
July Challenges
Find a scanned image PDF that you can convert with SensusAccess, and convert it to a tagged PDF. Don’t have a PDF to use? Try our practice scanned image PDF. What do you notice has changed in the new version of the document?