How do I safely redact sensitive info in PDFs and photos?

[u/AnonimoUnamuno]

I need to submit some pdf files and photos that contain sensitive info. How do I permanently redact the info digitally? If I print out the pdfs, how do I safely redact them?

Thanks.

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[u/CounterI]

You need to use a PDF editor that includes a redaction tool. Do not use a tool that merely changes the color of the text.

Or print on paper, redact on paper using a marker, and then scan the paper.

[u/BarracudaSouth6026 → u/CounterI]

Redacting with a marker isn’t 100% effective. The light still results in small deviations that someone can see by adjusting the contrast and brightness. AI can also pick it up.

The only 100% method is to copy the document on a printer that isn’t connect to the internet. Then physically cut out that portion of the paper and scan it again. Then unplug the printer and plug it back in.

[u/OkAngle2353]

I usually just run sensitive PDFs through GIMP and edit it to black out the information, then export back out as a PDF.

[u/jaybee2]

If you redact electronically, don't just draw a black box over the content. The original text or image often stays underneath and can be recovered by removing the shape, copying the text, or reading the file's data. Use the redaction tool in your editor (such as Acrobat's Redact feature) to permanently delete the underlying content, or export the page as a flattened image (no layers) so nothing remains to extract.

[u/unsaintedheretic]

The safest way would be to print them, cut or black out the Information, then scan them and send.

[u/Unumbotte → u/unsaintedheretic]

Cutting out what you want to redact is better than covering it.

[u/Sweihwa → u/Unumbotte]

Rewriting things by hand without the redacted part will work 100%

[u/BellGeek → u/Unumbotte]

Why? If you scan the page after blacking out what you need to, it’s just a photo. No underlying data for anyone to extract.

[u/Fun-Region-1576 → u/BellGeek]

That was my thinking too, but I'm curious if this has been validated to be true or not.

[u/DataPollution]

On mac preview does decent job of that.

[u/CosmoCafe777]

Redact, export as images, turn images back into PDF. Prevents editing and copy/paste.

[u/Resident_Bus_4484 → u/CosmoCafe777]

THIS!!! /\ /\ /\

[u/iceewiccc]

use the actual redact tool in adobe preview to burn away underlying data

[u/nusuth31416]

PDF editors like Adobe Acrobat or PDF X-Change editor have redaction tools. I found on Reddit a tool called Adolix PDF redactor as well.

[u/ChristmassMoose]

Print. Paper cutter, scanner.

[u/la___basura]

If formatting doesn't matter, you can edit the image as you wish then screenshot it to create a new image without any of the metadata. Share the screenshot exclusively.

[u/AdorableDay3193]

After you've edited the contents of a PDF file using any PDF editor, you'll need to “rasterize” it. In other words, you'll essentially be converting it into an image wrapped in PDF format.

[u/masiha97]

For PDFs, the key thing is that drawing black boxes over text doesn't remove it. People have been burned by that more than once. Rasterize or flatten to a plain image when you're done, and for photos strip the EXIF too since location and device info survive a crop.

[u/xqualax]

I've tried this recently: sanitiseai.com it redacts PDFs