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Comment by JumpCrisscross | Hacker News Reader

> Just the smallest variation in places that have been inked twice will reveal the clear text

Sure. But anyone can visually examine this. That means everyone with situational context can directly examine the quality of the redaction.

Contrast that with a digital redation. You have to trust the tool works. Or you have to separate the folks with context from the folks with techical competence. (There is the third option of training everyone in the DoJ how to examine the inner workings of a PDF. That seems wasteful.)

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> But anyone can visually examine this.

Can they? In principle it could be the difference between RGB 0.0,0.0,0.0 and RGB 0.004,0.0,0.0, that could be very difficult to visually see, but an algorithm could unmask the data with some correlation.

If you do it digitally and then map the material to black-and-white bitmap, then that you can actually virtually examine.

> Contrast that with a digital redation. You have to trust the tool works.

While true, I think the key problem is that the tools used were not made for digital redaction. If they were I would be quite a bit more confident that they would also work properly.

Seems like there could be a product for this domain.. And after some googling, it appears there is.

> While true, I think the key problem is that the tools used were not made for digital redaction. If they were I would be quite a bit more confident that they would also work properly.

Adobe Acrobat's redaction tools regularly feature in this sort of fuck-up, and they are (at least marketed as being) designed for such use

It's probably fine, but certainly better than what's being discussed ITT.

The larger point is that the "usual" redaction involves a tape pen or paint-style ink (dries opaque), IIRC, then photocopy, because the blocked out area is opaque. Scanner is probably no different than photocopy for these purposes.

Just scan it with black/ white setting.

> anyone can visually examine this.

They can't, if the variations are subtle enough. For example, many people are oblivious to the fact that one can extract audio from objects captured on mute video, due to tiny vibrations.

Analog is the worse option here. Simple screenshot of 100% black bar would be what a smart lazy person would do.

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