
Gamma Steganography - denormalfloat
https://carlmastrangelo.com/blog/gamma-steganography
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crankylinuxuser
I remember this trick was used years ago on 4Chan /b/

It was known how a thumbnail looked when it was generated by 4chan, so knowing
that could be used to generate the appropriate compressed image with a 'bait'
thumbnail.

It was common to show sexy females in the thumbnail image, and then when
opened, you'd be greeted by goatse (guy naked, with his hands pulling apart
his buttocks).

Nobody knew what it was called, but someone created an informal script,
attached it to a zip file, and appended the zip to the end of an image. Then
said image was uploaded to 4chan /b/.. And the jokes commenced.

I still have a few of them, but they're at home and I'm at work. And lets say
they're nsfw/nsfl.

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MrEldritch
Y'know, right up until today, I'd never actually known how the hell those
actually worked.

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rgovostes
The trick does not work on Safari, but you can click and drag the first image
and the drag preview will reveal what other browsers show.

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aaaaaaaaaab
(Or 3D-touch on mobile Safari)

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00N8
this is a really cool trick. I don't think steganography is the right term
though, when the 'hidden' image is viewable in most browsers

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torstenvl
Stenography is a recording something in real-time, e.g., taking minutes,
court-reporting, taking dictation, etc.

Steganography is entirely different, referring to the hiding of information
inside other information.

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sctb
We've reverted the title from “Image Stenography using Gamma”.

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wyldfire
Please correct the title. s/Stenography/Steganography/

