I’m really liking this, thank you for the suggestion.

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

(minor attracted persons aka PDF file joke)

Wow, this is awesome, thanks!

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.

You should spread that idea around more, it’s pretty ingenious. I’d add first converting to B&W if possible.

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 5-15 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.

Another ‘neat’ technology everyone should know about is machine identification codes, or, the tiny secret tracking dots that color printers print on every page to identify the specific make, model, and serial number (I think?) of the printer the page was printed from. I don’t believe B&W printers have tracking dots, which were originally used to track creators of counterfeit currency. EFF has a page of color printers which do not include tracking dots on printed pages. This includes color LaserJets along with InkJets, although I would not be surprised if there was a similar tracking feature in place now or in the future “for safety and privacy reasons,” but none that I am aware of.

Good question. I believe the browser “Print to PDF” function simply saves the loaded PDF to a PDF file locally, so it wouldn’t work (if I’m correct.)

I’m not an expert in this field, but you can ask on StackExchange or the author of MAT or exiftool. You can also do it yourself (I’ll explain how) by making a PDF with a jpg file with your metadata, opening it and printing to pdf, and then extract the image Do let us know your findings! I’m on a smartphone so can’t do it.

If you do try it yourself, a note from the linked SE page is that you won’t be able to extract the original file extension (it’s unknown, so you either have to know what it is, or look at the file headers, or try all extensions), 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 easy examples for our purpose.

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

(command line here, but there are exiftool GUIs)

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

Adds Phil Harvey and the copyright information to the file. If you’re on a smartphone and have the time and really have to know, then hypothetically there should be web-based tools for every step needed. I’m just not familiar with any and it’s possible the web-based tool would remove the metadata when creating or extracting the PDF.

@grue@lemmy.world has whored his karma already, he isn’t answering these additional questions which call into question his false assumptions.

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.

So it’s semi-related in that GrapheneOS protects against this type of attack.

It’s new as of about 1-2 months ago.

Passcode. Not fingerprint.

Unfortunately that wouldn’t work as this is information inside the PDF itself so it has nothing to do with the file hash (although that is one way to track.)

Now that this is known, It’s not enough to remove metadata from the PDF itself. Each image inside a PDF, for example, can contain metadata. I say this because they’re apparently starting a game of whack-a-mole because this won’t stop here.

There are multiple ways of removing ALL metadata from a PDF, here are most of them.

It will be slow-ish and probably make the file larger, but if you’re sharing a PDF that only you are supposed to have access to, it’s worth it. MAT or exiftool should work.

Edit: as spoken about in another comment thread here, there is also pdf/image steganography as a technique they can use.

Yes, we could have an internet without businesses. See here.

This sounds like the kind of thing a Zoomer who has no memory of life before the Internet – or the Internet of the '90s before the advertisers got a hold of it, for that matter – would write.

To clear that up, I’m coming up on 40. We got our first family computer with a 56k modem in 1995. I’m not saying ads are a good thing, I’m telling you that 99% of websites are ad-powered.

Back then companies had websites as a novelty, or way to find information about their company. All the newspapers that had websites were simply putting their major articles on the internet as a bonus, and as a business strategy to push subscriptions for their physical paper. Most everyone still purchased a subscription to their physical newspapers and magazines. Now, basically nobody has a newspaper or magazine subscription unless it’s online, but most people still don’t… The tech savvy use archive.ph and similar, and the old and non tech-savvy use their 3-article limit and might buy a month subscription to read an article they really have to read, or maybe even a year like the old days, but most don’t pay for a subscription at all, and that’s where the ads come in.

However, since social media has become the dominant news-spreading mechanism, many or most don’t even read articles. They read headlines and talk shit or ask questions in the comments section, of things which were answered in the article. In the 90s those people would be reading the articles as something to do, and to stay somewhat informed. Today, their smartphone would ding or buzz before they finished the first article.

P.S. I’m Degoogled and use Graphene without GSF on my main profile so I use Aurora, Neo Store, and F-Droid. Currently using Boost installed with Aurora. What’s a good recommendation for a good, fast, FOSS Lemmy client that doesn’t show ads that I can get with F-Droid?

Those are not businesses. They are free projects which a dedicated person (or group of people) donate their time and energy to produce.

Wikipedia has their semi-annual donation drives and many (not most, but enough worth mentioning) FOSS devs are salaried by companies like Google and Microsoft and are allowed to work on patches to out-of-scope projects on company time provided they’re still fulfilling their main roles. There are also Liberapay, Open Collective, Ko-fi and such but for the majority of FOSS devs not funded by large corps, just developing a large and widely-used program because they want to, donations rarely ever cover as much as they would make at a 9-5. There are also nonprofits that distribute donations to FOSS devs. For most it is a money pit, but to them the passion is worth more. They do it for the love, not the money.

These are not businesses.

“I have PERSONALLY spoken to GOD, and HE said I FORGIVE YOU, MY CHILD!”

“Amen!”"Amen!“Amen!”“Amen!”

There are articles about studies, and there are articles of investigative reporting. This is the latter.

“…Things like that, you know, the usual big guy lies” said Ford Prefect “You know, I’m not even so sure they were wrong” said Zaphod Beeblebrox in a relaxed tone. “I mean suuure, maybe on some idiotic races here and there like humans or…” “What? What about humans?” Piped Arthur Dent.

What are your suggestions besides ads and subscriptions, professor?

That’s a nice thought.

Then you suddenly realize no one knows up from down or down from up. Society would shift on such a massive scale people would probably just stick their smartphones in a drawer and only use them to message people they already know personally and check them a few times a day like an answering machine.

Then suddenly you realize you haven’t heard about Ukraine, Russia, Israel or Palestine in months. It’s November 28th and you heard someone mention a ‘new president’ but you didn’t even vote. Shit, you forgot to vote. There were no social media or news websites reminding you about the election and you didn’t have it on your new wall calendar yet! Ah that’s what all those “Vote Now!!!” yard signs were about, fuck…

It’s a nice thought, but the internet is powered by ads. (Almost?) Every subscription-supported website is also ad-supported. The internet would basically go under. AFAIK all the Lemmy apps have ads too. It’d be a nice change to get back to get a force shove back to the early-mid 90’s. Maybe we’d do things differently. People would certainly be outside talking to each other a lot more.