Optical Character Recognition (OCR) is technology that recognizes text within scanned documents and images. A scanned PDF may contain only an image of the text rather than actual searchable text. OCR converts image-based text into text that can be selected, searched, and read by assistive technologies.
Important: Running OCR is only one step toward making a PDF accessible. After using OCR, the PDF should also be checked for other accessibility requirements, including document structure and tags, reading order, headings, alternative text for meaningful images, document language, tables, links, and form fields when applicable.
How to use OCR in Adobe Acrobat
- Open the scanned PDF in Adobe Acrobat.
- Select All tools > Scan & OCR.
- Under Recognize Text, select In this file.
- Select the appropriate pages and document language.
- Select Recognize Text.
- Review the recognized text for accuracy and correct any errors.
- Save the updated PDF.
OCR creates a searchable text layer in the PDF. Be sure to review the results, since OCR may not recognize every word correctly.
Learn more: Recognize Text in Scanned PDFs — Adobe Acrobat