Documents
Accessibility issues with scanned documents
Scanned PDF documents are inaccessible to users of assistive technology. Why? Because, in most cases, a document scanned directly to PDF will be transferred as a large image file and is not searchable or readable. In addition, the document has no logical reading order or organisational structure which assistive technology can understand and interpret.
To the assistive technology user, the document appears completely blank.
Creating an accessible document
You must convert the image of the document into ‘real’ text ensuring the text is selectable and scalable.
With Adobe Acrobat this is done through Optical Character Recognition (OCR). To do this:
Select 'Document’ > ‘Recognise Text Using OCR’ > ‘Start’.
Once the document is converted you'll need to optimise the PDF document as normal adding bookmarks, tags and adding alternative text for images.
Please be aware that the quality of OCR can be a bit hit and miss and some strange characters and formatting be may produced on the resulting document.