In daily work, many clients use mobile phones to take photos of paper documents to create PDF files and then send them to us. However, scanned PDFs often have a grayish background and blurry text, which greatly affects readability, printing, and recognition. What can be done about this problem? Here’s a tip to completely remove the gray background from scanned PDFs, turn the base color white, make the text clearer, and enhance print quality.
Use Case for Changing Gray Background of PDF Scans to Pure White
1. Many scanned paper documents have gray, yellow, or shadowed backgrounds, which make the text content unclear, especially when projected onto a large screen, appearing even more blurry. Therefore, we need to turn the background of PDF scans to pure white and darken the text color to make the content clear and readable.
2. When we receive PDF scans from clients and need to print and archive them, the gray background greatly affects the printing quality, resulting in a dirty-looking paper document with unclear text. Converting the PDF scans to a white background with black text can improve the printing effect, making the printed documents cleaner and more professional.
3. If we want to perform OCR text recognition on PDF scans, gray or shadowed backgrounds will seriously interfere with OCR, leading to failures or many errors, which then requires us to spend a lot of time adjusting and correcting. After removing the gray background from the scans, the clarity and contrast of the text can be improved, making OCR recognition easier.
Preview of the Effect After Removing Gray Background from PDF Scans to Make Them Clear
Before processing:
After processing:
Steps to Batch Remove Gray Background from Scanned PDFs and Whiten the Base
1. Open HeSoft Doc Batch Tool , select PDF Tools → Sharpen Text on PDF Image.
2. Click Add Files or import files from a folder to add all the PDF files that need processing.
3. You can freely drag the slider to adjust text clarity. Here we set the text clarity to 45%. You can also adjust brightness, contrast, and sharpness to make the text on the PDF images clearer. Feel free to set these according to your actual needs.
4. After processing is complete, click the save location directly to view the processed PDF files. All scans have had their gray backgrounds removed, and the background has become pure white, making them easier to read and print.
