Author Topic: Don't pixelate text (or blur or swirl) text to hide it  (Read 640 times)

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Offline Jason

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Don't pixelate text (or blur or swirl) text to hide it
« on: August 15, 2022, 02:16:01 pm »
Pixelation isn't a good way of hiding underlying text. The video and article on this website show how the author created a tool to un-pixelate text. He also suggests that blurring or swirling aren't any better (although doesn't go into why). The video is just over 4 minutes long. Watch it at 1.25 speed and it's still watchable and quicker. :)

https://bishopfox.com/blog/unredacter-tool-never-pixelation

Using black bars is the only surefire way of obfuscating it, assuming you actually lay a bar over it and don't just change the background and foreground colours in a word processor document which is useless.

It's an interesting foray into why pixelation is such a bad idea as well as how the tool works.

I need to try this sometime when I see someone pixelate someone's name on a screencap of a Facebook post. I'll let you know if I do.
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Offline ssfc72

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Re: Don't pixelate text (or blur or swirl) text to hide it
« Reply #1 on: August 16, 2022, 05:47:03 am »
Good info to know, about using pixelation on a text document. Thanks Jason.

In my photo of my car, I used a Cut tool, to remove the licence plate info. This results in a black bar being used to replace that area of the photo, so I would think that information would not be recoverable.
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Offline Jason

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Re: Don't pixelate text (or blur or swirl) text to hide it
« Reply #2 on: August 18, 2022, 07:51:23 pm »
Yeah, black bars should be fine.
* Pop!OS 22.04 on a PC desktop with a 3.4 GHz i5 (quad-core) processor, 12 GB RAM, 512 GB Kingston SSD and dual 24" displays
* Lenovo 300e Chromebook (2nd generation)
* Motorola Edge (2022) - Android 11, 8 GB RAM, 256 GB storage, 2400 x 1080 display, Cameras: 32 MP front, 50 + 2 + 13 MP ba