How to Fix Acrobat Highlighting Areas Instead of Individual Text
Question details
The user wants to highlight individual words or characters in a PDF, but the software highlights large block areas instead.
- Product
- Adobe Acrobat
- Device & OS
- not provided
- Scenario
- Annotating or editing a scanned PDF document using the highlighter tool.
- Observed behavior
- The highlighter tool selects a large, non-specific blob or area instead of snapping to specific characters or words.
Check if your PDF is a scanned document by trying to select a single word with your standard mouse cursor; if you cannot select the text, the document is treated as an image and requires OCR processing.
Use the Scan & OCR Tool to Recognize Text
Converting the scanned image into selectable text will allow the highlight tool to snap properly to individual letters and words.
When a PDF is created from a scanner, it is treated as a single flat image layer. Acrobat's highlighter defaults to an area-select mode because there are no underlying text characters to anchor to.
Performing OCR (Optical Character Recognition) solves this by identifying the letters in the image and generating an invisible layer of selectable text over them.
Launch Adobe Acrobat and open the scanned PDF document that is causing the highlighting issue.
Navigate to the 'Tools' menu at the top of the screen and select 'Scan & OCR' (labeled as 'Recognize Text' in older versions).
Click on 'Recognize Text' in the toolbar and choose 'In This File'. Select your document's primary language and click 'Recognize Text' to begin the conversion process.
Once the OCR processing is complete, select the Highlight tool again. You should now be able to accurately select and highlight individual words.
Easily Highlight and OCR PDFs with WPS Office
Avoid the frustration of clunky highlighting in scanned documents. WPS Office features a robust built-in PDF reader and editor equipped with powerful OCR technology, allowing you to seamlessly convert scanned documents into selectable, highlightable text in seconds.
- 1. Open your PDF: Launch WPS Office and open your scanned PDF file using the WPS PDF tool.
- 2. Run OCR: Navigate to the 'Tools' tab on the top ribbon and select the 'OCR' feature.
- 3. Convert Image to Text: Follow the prompts to extract or convert the image to text so the document becomes fully searchable.
- 4. Highlight Perfectly: Switch to the 'Comment' tab, select the Highlight tool, and perfectly select individual words without creating large blocks.
Frequently Asked Questions
Why did my highlighter suddenly start making square blobs instead of selecting text?
This happens when you open a scanned PDF or an image-based document that does not contain a text layer. Without recognizable text, the software uses a free-form area highlight. Running OCR will restore normal word-by-word highlighting.
Can I highlight a large area without converting the text?
Yes. Most PDF editors, including Acrobat and WPS PDF, allow you to use an 'Area Highlight' tool or standard drawing shapes (like rectangles with customized opacity) to intentionally mark sections of an image-based PDF without running OCR.
Is OCR text recognition included for free in PDF readers?
Basic text recognition availability varies by software. Adobe Acrobat requires a paid Pro subscription for full OCR capabilities, while WPS Office offers robust PDF tools and OCR options in its premium tiers, often with free trial capabilities.
