Fix Acrobat Highlighter Selecting Large Oval Areas After OCR
Question details
The user needs to fix the highlight tool in Adobe Acrobat, which is selecting large image blocks instead of actual text lines after performing OCR on a document.
- Product
- Adobe Acrobat
- Device & OS
- not provided
- Scenario
- Highlighting text in a scanned PDF document after running Optical Character Recognition (OCR).
- Observed behavior
- The highlighter tool selects a large oval or image-shaped region rather than individual words, letters, or lines.
Ensure you are working with a clear, high-resolution scanned document, as poor scan quality, shadows, or skewed pages can severely degrade OCR accuracy and cause text selection issues.
Run Text Recognition Again with Correct Settings
Re-running the OCR process with specific language and scan quality settings can fix an inaccurate hidden text layer, allowing the highlighter to snap to actual text.
When Acrobat's highlighter selects large graphical shapes instead of words, it typically indicates that the document is still being treated as an image, or the initial OCR text layer is misaligned.
Open your PDF in Acrobat. Go to the 'Tools' menu and select 'Scan & OCR'.
Click on 'Recognize Text' in the toolbar and choose 'In This File' from the dropdown menu.
Click on 'Settings' (the gear icon). Ensure the Document Language matches your text, and set the Output to 'Searchable Image'. Set the Downsample To option to at least 300 dpi.
Click 'Recognize Text' to process the document again. Once finished, select the Highlight tool and attempt to highlight individual words.
Optimize and Enhance the Scanned Document
Enhancing the document clears up background noise and straightens the page, which helps the OCR engine distinguish text from the background.
Edit and Highlight Scanned PDFs Accurately with WPS PDF
Avoid frustrating highlight selections and inaccurate text recognition by using WPS Office's built-in PDF OCR feature. It accurately extracts and layers text from images, allowing you to highlight, edit, and annotate seamlessly without complex settings.
- 1. Open Your PDF: Launch WPS Office and open your scanned PDF document in the WPS PDF reader.
- 2. Run the OCR Tool: Navigate to the 'Tools' tab on the top ribbon and click on 'OCR'. Follow the prompt to convert the scanned image into a searchable PDF.
- 3. Select the Highlight Tool: Go to the 'Comment' tab and click on the 'Highlight' icon.
- 4. Highlight Text Accurately: Drag your cursor over the recognized text. WPS PDF will smoothly snap the highlight to individual words and lines.
Frequently Asked Questions
Why does my PDF highlight as a giant box instead of text?
This happens when the PDF reader interprets the page as a single flat image. If the OCR (Optical Character Recognition) process fails, hasn't been run, or the text layer is misaligned, the software doesn't recognize individual characters, causing the highlighter tool to select the whole graphic area.
Can I remove hidden text layers in Acrobat and start over?
Yes, if an initial OCR scan produced corrupted or misaligned text, you can use the 'Sanitize Document' or 'Remove Hidden Information' tool in Acrobat to strip out the hidden text layer. Once removed, you can run the 'Recognize Text' tool again on a clean slate.
Does scan resolution affect OCR highlight accuracy?
Absolutely. Scans captured at low resolutions (below 300 DPI) often contain blurry edges and digital noise. This leads to poor OCR results, causing text to be misinterpreted as images or irregular shapes by selection and highlight tools.
