Fixing Image-only PDFS: Text/Character Recognition in Acrobat DC
Do I have an image-only PDF?
Often you will inherit a PDF file that was scanned as an
image of text. This means that a sighted person can read it,
but a screen reader cannot. You can tell if you are in this
situation in a couple of ways. If you try to copy some of the
text in your document and paste it into a new document,
you will find you are unable to highlight just the text you
want. Also, if you try to run the accessibility checker, you
will get the Image-only PDF error. You will not be able to
continue fixing accessibility until this error has been fixed.
Fixing the Error
Once you 've established that you have an image-only
PDF, you need to do a few things before working on your
other accessibility issues.
1. Close the Accessibility toolset for now.
2. Open the Enhance Scan toolset (Older versions of Acrobat may not have this tool, but they might have
Text Recognition or OCR Text Recognition toolset. These tools aren't as robust, but they may work with
very clear scans, so they are worth a try).
Finding similar tools in an older version of Acrobat
What the toolset button looks like in Acrobat
Professional DC
3. A new toolset should appear across the top. Click on Enhance.
4. A pull-down menu should appear with options. Select Scanned Document.
5. A subset of tools should then appear below. Make sure to check the box for Recognize Text and then click
the Enhance button.
6. The computer will process for a few seconds to a minute. It will straighten your image and enhance
contrast to improve readability. Then Optical Character Recognition will automatically run and try to
identify text in your image. When it is finished, you should be able to highlight your text. If all of the text
can be highlighted, close the Enhance Scan/Text Recognition toolset and open your accessibility toolset.
7. Continue with the accessibility guide for PDFs.
Note: If your original image was of poor quality, you may not be able to highlight all of your text. If any
text does not highlight, the computer was unable to process it. This means a screen reader will be unable to
read it. At this point, please save the file as a new version and send it and the original to
webaccessibil[email protected]. We will evaluate if anything more can be done for the file.
