Redacting a Scanned or Photographed PDF: When the PDF Is Made of Images
Key points
- Image-based PDFs can be redacted the same way
- Choose the quality
- After redacting, check the text has not blurred
A scanned PDF, or a PDF of a document photographed with a phone, has each whole page as one image. You can redact these PDFs in Black Out (Redact) Parts of a PDF with the same steps.
About image-based PDFs
- The text is part of the image to begin with, so it cannot be selected or searched.
- When you redact, the image is painted over in black in that area.
Steps
- Choose the PDF in Black Out (Redact) Parts of a PDF.
- Drag with your finger or mouse over the parts to hide.
- Choose the "Quality of redacted pages".
- Standard (150 dpi): a light file, good for ordinary documents.
- Fine (200 dpi): good for documents with small text. The file gets larger.
- Tap "Black out and create PDF" and save.
About quality
Redacted pages are recreated as images again, so the quality can be slightly lower than the original. If small text becomes hard to read, choose "Fine (200 dpi)".
If the file gets large
Use Compress PDF to make it smaller.
If tilt or margins bother you
First tidy the margins with Crop PDF Margins, then redact; the position is easier to choose.
Use "Black Out (Redact) Parts of a PDF" (free)Tools that go well with this
- Convert a PDF to Grayscale (Black & White): Turn a color PDF into grayscale or pure black and white, ready for monochrome printing, copying or fax. Choose the resolution.
- Extract or Delete PDF Pages: Keep only the pages you need, or remove the pages you don't.
- Compress PDF: Shrink a PDF to fit under a size you choose, for upload limits.
More guides for this tool
- How to Black Out Part of a PDF (Free, Works on a Phone)
- Why Putting a Black Box on Top Is Not Enough: The Right Way to Redact a PDF
- Information to Hide Before You Submit: When to Consider Redacting a PDF
- How to Check a Redaction Worked: Select, Search and Open in Another App
- Redacting the Same Place on Every Page: Headers, Footers and Name Fields
- Checklist Before Sharing a PDF: Redaction, File Name, Pages and Size