Reduce OCR Font Size in Acrobat Editable Text and Images
Question details
The user wants to reduce PDF file size bloated by a massive number of custom fonts generated when using the Editable Text and Images OCR mode in Adobe Acrobat on long scanned books.
- Product
- Adobe Acrobat
- Device & OS
- not provided
- Scenario
- Running OCR on large scanned documents or books while trying to maintain a manageable file size and preserve image quality.
- Observed behavior
- Acrobat creates numerous custom fonts for similar characters during OCR, greatly increasing the PDF file size, and sometimes blurs images containing text.
Before applying these workarounds, ensure you have backed up the original scanned PDF, as optimization and re-processing can permanently alter image quality and text layers.
Switch to Searchable Image OCR Mode and Optimize
Since Acrobat lacks a custom similarity threshold for fonts, using the Searchable Image mode paired with standard optimization tools is the best way to reduce file size without distorting graphics.
The 'Editable Text and Images' mode attempts to perfectly recreate the visual style of your scan by generating unique vector fonts, causing file bloat. Changing the OCR output style prevents this issue.
Open your document in Acrobat, select the 'Scan & OCR' tool, click 'Recognize Text', and open the Settings (gear icon). Change the Output from 'Editable Text and Images' to 'Searchable Image'.
Click 'Recognize Text' to process the document. This method overlays a hidden text layer rather than creating thousands of custom fonts, keeping the file size lower.
Go to 'File' > 'Save as Other' > 'Optimized PDF'. Here you can audit space usage and downsample unnecessary image resolutions to further compress the document.
Export and Re-OCR the Document
This community-tested workaround involves exporting the OCR'd document to high-resolution images and running the process again to force Acrobat to consolidate its fonts.
Manually Separate Text and Images Using an Editor
If 'Editable Text and Images' blurs important graphics that contain text, you can use an image editor to separate them before running OCR.
Easily Extract Text and Compress PDFs with WPS Office
If Acrobat's OCR font bloat is slowing down your workflow, WPS PDF offers a highly accurate OCR engine that extracts editable text without bloating your file size, paired with an effective built-in compressor.
- 1. Open Your PDF: Launch WPS Office and open your scanned document or book in the WPS PDF editor.
- 2. Extract Text via OCR: Navigate to the 'Tools' tab and select 'OCR'. Choose your extraction preference to convert the image to text accurately without font bloat.
- 3. Compress the PDF: Click 'Compress' under the Tools tab, select your desired compression level, and instantly shrink your final file size.
Frequently Asked Questions
Why does Acrobat's Editable Text and Images mode create so many fonts?
Acrobat attempts to perfectly match the visual look of the scanned text by generating custom fonts for slight variations in ink and paper texture. In long documents, this results in hundreds of unique font subsets, severely bloating the PDF file size.
Can I set a font similarity threshold in Adobe Acrobat?
No, Acrobat currently does not provide a native setting or similarity threshold to merge OCR-generated fonts. You must rely on workarounds like changing the OCR output mode to 'Searchable Image' or using third-party PDF optimization tools.
Does switching to Searchable Image mode reduce PDF file size?
Yes. The 'Searchable Image' mode places a hidden, searchable text layer over the original scanned image instead of converting the visual text into custom vector fonts. This drastically reduces the number of embedded fonts, typically resulting in a smaller file size.
How can I compress a PDF after running OCR?
In Acrobat, you can use the 'Optimize PDF' tool located under the 'Save as Other' menu. This allows you to downsample overly large images, unembed unnecessary fonts, and discard hidden objects to reduce the final document size.
