How does image manipulation affect steganography?


Leave the archive and display this page in the standard design: Image manipulation: Hidden message in an image


Hello!

I have a small bitmap (48KB) here (http://www.d-mueller.de/quiz.bmp), which contains a hidden message (assume some form of text). Anyone have an idea how to track that down?

It definitely has something to do with image manipulation, so nothing can be torn with the naked eye. I've already tried the histogram, so far without any result.

greeting

Stego? http://www.thomaeum.de/projekte/stego/index.htm

You can also use a hex editor, maybe the message is hidden in a legible way. : D

The many square structures in the picture are striking, Stego only shows gibberish for me.

Can you program

With simple steganography algorithms, the information is "hidden" in the LSBs. So just paste the least significant 1 to 2 bits of each byte back together to form new bytes and see if something makes sense.

edit:
Jo Stego works like this: D - so try more than 1 bit there
It can of course be that the Algo used is incompatible with Stego because it does MSB-First, or because a completely different algorithm is used.

The background is that it should be possible to solve it with the GIMP. So don't think that HEX editors will continue there.

then try that


to recover the hidden image:
Open the container image.
add a new layer.
paste the original container image in the new layer and anchor it.
In the layers dialog select Difference in the mode menu. the image will turn black.
click Image> flatten image
click Colors> brightness / contrast.
set both sliders to maximum and click okay.
your image will be visible again!

then try that


Thanks first of all. Your source (https://www.instructables.com/id/How-to-hide-one-image-in-another-An-introduction-/step7/Get-it-back/) also says

Obviously the recipient of the hidden image will require a copy of the original.

I only have one picture. Since I can hardly make a difference.

I should have read more carefully; (

there are no more hints than "here is the picture"

is that with pallet? Then I would look for regular samples of individual pallet values, otherwise it's poking in the haystack ... unfortunately

I've played around with Gimp a bit, I can't think of anything.

In the image, the LSBs of the pixels were obviously manipulated. How to extract that with GIMP I don't know.

Somehow it looks like the picture was "xor" t in there.

Apparently the LSBs of the pixels were manipulated in the image. However, I don't know how to extract that with GIMP. Channel separation, bit depth reduced to 7 bits, which is again with the output image with brightness + 1 (i.e. one bit added), difference.

Kind regards

In the image, the LSBs of the pixels were obviously manipulated. How to extract that with GIMP I don't know.

Somehow it looks like the picture was "xor" t in there.

O RLY? What kind of program did you use there?

Channel separation, bit depth reduced to 7 bits, which again with the output image with brightness + 1 (i.e. one bit added), difference.

Kind regards

I'll try it in a few hours after work. Top!

The program is self-written and does nothing but display single or multiple bit planes of an image. Was created years ago for my specialist work on steganography to display things like that. The part is extremely simple, but seems to be enough for something like that.

The program is self-written and does nothing but display single or multiple bit planes of an image. Was created years ago for my specialist work on steganography to display things like that. The part is extremely simple, but seems to be enough for something like that.

Could it be that the author of this picture did something very similar and the thread starter his beta tester? ;)

I don't get baked.

I disassemble it into the HSV model, then make it by picture -> mode -> indexed 128 colors (2 ^ 7). Then I knock on a new level, increase the brightness by 1 and form the difference between the original and the (reunited?) 3 levels? Where is it with me?

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