@[email protected]
0 Followers
0 Following
12 Posts
Show threadSyn_AttckJun 20, 2024
I’m really liking this, thank you for the suggestion.
Show threadSyn_AttckJun 20, 2024

Whatever the format, let’s hope it doesn’t end up having the extension .map

(minor attracted persons aka PDF file joke)

Show threadSyn_AttckJun 20, 2024
Wow, this is awesome, thanks!
Show threadSyn_AttckJun 20, 2024
Unless you know specifically what they’re adding or changing this wouldn’t work. If they have a hidden ‘barcode’ and you add another hidden ‘barcode’ or modify the image in a way to remove some or all of theirs, they’d still be able to read theirs.
Show threadSyn_AttckJun 20, 2024
You should spread that idea around more, it’s pretty ingenious. I’d add first converting to B&W if possible.
Syn_AttckJun 20, 2024

This is a great point. Image watermarking steganography is nearly impossible to defeat unless you can obtain multiple copies of the ‘same’ file from multiple users to look for differences. It could be a change of a single 10-15 pixels from one rgb code off.

rgb(255, 251, 0)

to

rgb(255, 252, 0)

Which would be imperceptable to the human eye. Depending on the number of users it may need to change more or less pixels.

There is a ton of work in this field and its very interesting, for anyone considering majoring in computer science / information security.

Show threadSyn_AttckJun 20, 2024

Good question. I believe “Print to PDF” isn’t actually “printing” it page by page as if it was a physical printer, but rather just saving the loaded PDF to a PDF file locally.

I’m not an expert in this field, but you can ask on StackExchange, or ask the author of MAT and exiftools, or do it yourself by making a PDF with a jpg file with your metadata, and then extract the image and let us know here - it would be useful information that I can’t find via search engines. I’m using a smartphone so I can’t do it, but if you do, note from the linked SE page is you won’t be able to extract the original file extension, so if you use your own .jpg with your own exif data, rename to .jpg when finished (I believe exif is handled differently based on file type).

There are multiple tools to add exif data to an image but the exiftool website has some good easy examples for our purpose.

exiftool -artist=“Phil Harvey” -copyright=“2011 Phil Harvey” YourFile.jpg

(do this as the first step before adding to the PDF)

How to extract images from a PDF in their original format

I'm using pdfimages -j bar.pdf /tmp/image to extract images from a PDF. My objective is to get them in their raw state as they were added. So If it was a .tif I'd like to get a .tif, if it's a jp...

Stack Overflow
Show threadSyn_AttckJun 20, 2024
@[email protected] has whored his karma already, he isn’t answering these additional questions which call into question his false assumptions.
Show threadSyn_AttckJun 20, 2024
It’s not, technically, but if I have sensitive documents on my phone and a law officer is trying to get me to unlock my phone, I will be entering and/or putting the duress code into my phone. GrapheneOS has ‘lockdown’ button by ‘restart’ and ‘shutdown’ all of which will require a passphrase to unlock, even if you normally have fingerprint enabled for X hours each time of use.
Show threadSyn_AttckJun 20, 2024
It’s new as of about 1-2 months ago.