How to Fix Scanned PDF Text Not Highlightable on iPad
Question details
The user is unable to directly highlight text in a cleaned or scanned PDF using Adobe Acrobat Reader on an iPad, though text can be selected via the Comment tool.
- Product
- Adobe Acrobat Reader
- Device & OS
- iPad
- Scenario
- Attempting to highlight text in a scanned PDF document on a tablet for review or study purposes.
- Observed behavior
- The text cannot be directly highlighted because the PDF is treated as a flat image and lacks a selectable text layer.
Ensure you have access to a desktop or a PDF tool equipped with Optical Character Recognition (OCR) capabilities, as you will need to process the scanned document to recognize the text before highlighting it on your iPad.
Run OCR to Create a Selectable Text Layer
Use a PDF editor with OCR capabilities to convert the image-based scanned PDF into a document with searchable and highlightable text.
A cleanscanned PDF often consists entirely of image content without an underlying text layer that supports direct selection. By running OCR (Optical Character Recognition), the software identifies the text within the image and overlays an invisible, selectable text layer.
Transfer your scanned PDF to a computer and open it in a desktop PDF editor that supports OCR, such as Adobe Acrobat Pro or WPS Office.
Navigate to the 'Tools' menu and select 'Recognize Text' or 'OCR'.
Select the option to recognize text in the file. Make sure to choose an output setting like 'Searchable Image' or 'Exact'. This preserves the original look of the scanned document while adding an invisible text layer on top.
Start the OCR process. Once it is completed, save the newly generated PDF file to your device.
Send the updated PDF back to your iPad. Open the file again in Acrobat Reader; you should now be able to directly select and highlight the text.
Use WPS Office to OCR and Highlight Scanned PDFs
WPS Office features a powerful PDF toolkit, including a built-in OCR engine that quickly converts scanned images into fully selectable and highlightable text, making document review on any device a breeze.
- 1. Open your PDF: Launch WPS Office on your computer and open the scanned PDF.
- 2. Access the OCR tool: Navigate to the 'Tools' tab on the top ribbon and select the 'OCR' function.
- 3. Recognize text: Choose the option to extract text or convert it into a searchable document format, preserving the original layout.
- 4. Save the file: Save the newly generated searchable PDF to your local drive or cloud storage.
- 5. Highlight on iPad: Open the processed document on your iPad using the WPS Office mobile app to effortlessly highlight and annotate the text.
Frequently Asked Questions
Why does a PDF act like an image instead of text?
When a document is scanned, it is essentially captured as a photograph. Unless Optical Character Recognition (OCR) is applied, the PDF reader only sees a flat image with no underlying text data to select, copy, or highlight.
Can I run OCR directly on my iPad?
Yes, some advanced PDF applications for iPadOS offer mobile OCR features. However, for the most accurate results and advanced settings (like 'Searchable Image'), processing the file on a desktop application before sending it to your iPad is often recommended.
What does 'Searchable Image' mean in OCR settings?
'Searchable Image' is an OCR mode that keeps the original visual appearance of the scanned document while placing an invisible layer of recognized text perfectly over it. This allows you to search, select, and highlight without changing the document's original look.
Will running OCR change the formatting of my PDF?
If you use the 'Searchable Image' or 'Exact' mode during the OCR process, the visual formatting remains untouched. Only an invisible text layer is added. If you choose 'Editable Text', the software will replace the image with actual fonts, which might alter the formatting.
