How to Edit and OCR Only Part of a Scanned PDF Page
Question details
The user wants to recognize (OCR) and edit only a selected portion of a scanned PDF page while leaving the rest of the document unchanged.
- Product
- Adobe Acrobat
- Device & OS
- not provided
- Scenario
- Editing a scanned PDF document where only a specific region or paragraph requires text recognition and modification.
- Observed behavior
- Acrobat's standard OCR workflow processes the entire page or document by default, lacking a direct tool to execute precise partial-page text recognition.
Before starting, ensure that your scanned document has sufficient resolution (at least 300 DPI) for accurate OCR processing, and work on a duplicate copy to avoid unintended modifications to the original file.
Use the Page Cropping and Replacement Method in Acrobat
Since Acrobat processes entire pages by default, you can isolate the target area by duplicating the page, cropping it to the required region, running OCR, and placing the corrected text back.
This workaround effectively bypasses Acrobat's full-page OCR limitation by artificially creating a page that only contains your target area.
Open your PDF in Acrobat, go to the 'Organize Pages' tool in the right-hand pane, hold the Ctrl (or Option) key, and drag the page containing your target section to duplicate it.
Select the duplicated page, open the 'Edit PDF' tool, select the 'Crop Pages' option, and draw a rectangle strictly around the portion you want to recognize. Double-click inside the rectangle and click 'OK' to crop.
Navigate to the 'Scan & OCR' tool, select 'Recognize Text', and run the process specifically on the newly cropped page to make that section editable.
Edit the recognized text as required. Once finished, you can copy the corrected text box and paste it over the corresponding area on the original page, optionally covering the old scanned portion with a white background shape.
Easily Extract and Edit Text from Scanned PDFs with WPS Office
WPS Office provides a highly intuitive Screen OCR feature that lets you instantly select, recognize, and extract text from specific regions of a scanned PDF without modifying the original layout.
- 1. Open the scanned PDF: Launch WPS Office and open your scanned PDF document from the home screen.
- 2. Activate the Screen OCR tool: Navigate to the 'Tools' tab on the top ribbon and click on 'Screen OCR' (or 'Extract Text').
- 3. Select the target region: Click and drag your cursor to draw a box around the specific part of the page you wish to recognize.
- 4. Copy or save the recognized text: Wait a moment for WPS Office to process the image. A window will appear with the editable text, which you can then copy to your clipboard or save directly as a new document.
Frequently Asked Questions
Can I perform OCR on just one paragraph without affecting the images on the page?
Yes, by utilizing regional extraction tools like WPS Screen OCR, you can select only the paragraph you want to convert to editable text, leaving surrounding images and layout completely untouched.
Why is the OCR output inaccurate in my cropped PDF section?
Inaccurate OCR results are typically caused by low scan resolution, poor contrast, faded ink, or handwritten text. Ensure the original scan is saved at a minimum of 300 DPI.
Does extracting text using Screen OCR alter the original PDF file?
No. When using a screen extraction tool, the software simply reads the text from the selected area. The original PDF remains unmodified unless you manually delete or overwrite the area.
Is it possible to revert the OCR process in Adobe Acrobat?
If you have not saved and closed the file, you can revert the action using Ctrl+Z (Windows) or Cmd+Z (Mac). Otherwise, use 'Revert' from the File menu to restore the last saved version of your PDF.
