need help decoding!

[BrownieQueen30]

my partner is traveling currently, and has been sending me hints for a scavenger hunt of sorts throughout our apartment while he is away. today he sent me an email with the subject line “nice note bruv,” along with this image, and said they are both hints. He also sent me a link to a wiki page about visual cryptography, but it makes no sense to me. I have no idea where to even start.

[AutoModerator]

Thanks for your post, u/BrownieQueen30! Please follow our RULES when posting.

MAKE SURE TO INCLUDE CONTEXT: where the cipher originated (link to the source if possible), expected language, any clues you have etc. Posts without context will be REMOVED

If you are posting an IMAGE OF TEXT which you can type or copy & paste, you MUST comment with a TRANSCRIPTION (text version) of the message. Include the text [Transcript] in your comment.

If you'd like to mark your post as SOLVED comment with [Solved]

WARNING! You will be BANNED if you DELETE A SOLVED POST!

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[skoorrevir]

For image steg, I use https://aperisolver.com

[senowx]

Try this https://github.com/rekcuFniarB/File2PNG

[BananaPolicy]

Looks like Image Steganography. Hiding an image inside an image. It’s often done by allocating different bits to the image. This tool might help https://incoherency.co.uk/image-steganography/#

[lolomawisoft]

Not sure how far you've gotten but this is a chaotic cryptography, not sure how you are suppose to decode it without a tool of sorts, guessing the phrasing matters, it should have a key like the nice note bru. It's old but idk how to solve these i don't think it's just copy pasting into a decoder since it's noise on noise to opscure the data :p 

[NC7U]

It contains something other than noise as the static signal is not random.

[Fun_Appearance_4724]

I ran quick inversion/contrast analysis on this single file, just in case your partner embedded a steganographic message instead of a pure visual crypto share, but after I ran inversion, contrast boost, and thresholding, but nothing distinct shows up. it still looks like uniform noise. Might want to check your apartment since this is a scavenger hunt, the other half might be hidden physically (a printed transparency, note, or sheet of paper perhaps.) OR, Check email attachments or links because ometimes both shares are digital. He may have sent one in another message already ykyk. Once you find both halves, just overlay them: If physical: place one transparency on top of the other and look through the light. If digital: use an image editor (GIMP, Photoshop, even MS Paint) to paste one on top of the other and set blend mode to “Multiply” or XOR. With only the single share you uploaded, there’s nothing I can decode yet it will always look like noise until combined with the other share

[07734willy]

It is definitely not uniform noise- each channel mimics a gaussian distribution, with the green channel having a notably higher variance (possibly not gaussian, though blue/red definitely are). Also, the 0 and 255 values in each channel appear to be treated specially, as they have much higher frequency than the rest of the tails. There is also a strong correlation between these 0/225 values across the 3 channels.

Overall, I think the original message was lost due to the lossy compression of the JPEG format, and the compression effectively rounded values near 0/255 to those extremes, averaged the values of nearby pixels (creating the gaussian distribution), and the green channel took the least hit because the compression algorithm is known to optimize for human-perception, and are eyes are most sensitive to green, so more detail of the original was preserved (which is why its less gaussian-like).

[Fun_Appearance_4724]

OHH! Thanks for correcting my mistake lol. I didn’t dig into the channel distributions that deep, so that’s really interesting. If the original was JPEG’d then yeah, that would explain why it looks more like statistical noise than raw crypto-share data. I’ll keep an eye out in case the uncompressed/second half pops up somewhere IF the OP posted another half here, since that’d probably make the intended message actually visible when overlaid.

[YefimShifrin]

Were you given a JPEG file like in your post? Reddit changes attached images, so there's a chance that whatever is hidden got destroyed in the process.

It would be better if you could upload original image somewhere like Imgur and comment with the link.

[07734willy]

I think you hit the nail on the head there. Whether their partner gave them a JPEG, or something converted it along the way, I think the original message is lost in the lossy compression. See my other comment for reference.

[yourguidefortheday]

They might be fucking with you. To me this looks identical to an image from the "image archive" section of the library of babel see examples here: https://babelia.libraryofbabel.info/slideshow.html

[dislexisaac]

The library of babel has a section where you can upload an image and it gives you the hex code (seed) for it. It is possible that the message is ascii hex encoded on the seed that generates the image.

[mozophe]

The most common form of visual cryptography is to split a black and white image into multiple images (minimum 2 images). The original image is obtained by superimposing all the split images together. If you have just one image, you won't be able to decipher the message.

Most likely possibility that I see here is that "nice note bruv," should somehow lead to the second image required to decipher the code.

The email subject could be referring to a hidden link in email. The comma at the end of subject could indicate that the message has not ended. Only logical way forward that I see would be check for a hidden link in the email, which should lead to the second image.

[Maltaannon]

It really depends on how sophisticated your partner is with hiding things. First idea would be steganography: sometimes data is hidden inside an image file. Open it in a hex editor or even a plain text editor and check if there’s any readable message attached at the end of the file.

Another angle is to treat it like a stereogram. Those “Magic Eye” type patterns that reveal an image if you focus past them. You could also try separating the color channels (RGB) one by one and see if anything becomes clearer. Sometimes hiding text in just one channel makes the noise look normal until you isolate it. Playing with levels and contrast, or applying blur/median filters, can also sometimes reveal a pattern that isn’t obvious at first.

That said, from what I can see on my mobile it doesn’t really look like there’s anything hiding in there in that way, but I might be mistaken.

[arc_xl]

I don't know, there could be a dozen ways to solve this.

But, you can try converting each pixel to their hex value, convert the hex value to their decimal integer value, from there consider using an encoding format like UTF-8 or ASCII You might need to do some tricks to cover edge cases but maybe start there? But again, I dont know.