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FalsiScan: Make it look like a PDF has been hand signed and scanned

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Re: FalsiScan: Make it look like a PDF has been hand signed and scanned

#52
post #27

Don't know about different Jurisdictions, but from where I am - this has NO legal binding whatsoever. We have those gov issued digital, invisible signatures for that, embedded in our personal ID card. Whatever is properly signed with digital signature, the printed out page bears no legal force. Anyway, businesses still like to do it this way ("Signing" pdf by applying some pixels). I wonder if it is just an inconveni…

Same over here! Only difference is that with our IDs/certs you usually have a visible cert block on the PDFs. You can get it to be invisible somehow, but that's a bit of a hassle. But yes, anything that's not a proper digital signature might as well just be a random png pasted into a pdf. No legal binding power whatsoever.

For the software they provide us to sign documents, there is a checkbox when I sign PDF files - whether I want some overlay that indicated that it is digitally signed or not. Thats probably the user friendly part of digital signatures :)

Re: FalsiScan: Make it look like a PDF has been hand signed and scanned

#54

Heh. Probably unnecessary to make it look like it was put in the scanner misaligned. Just scan the signature itself and past that image onto the image of the document.

Meh. That really doesn’t always look very legit. Especially if you can “select” all the text, and when you select the signature you see a nice box around it. It’s then too obvious it was added as an image. I don’t disagree that the whole “signing and scanning” is dumb, though.

You can rasterize the pdf, wouldn’t that solve it?

Re: FalsiScan: Make it look like a PDF has been hand signed and scanned

#55
post #48
post #27

Don't know about different Jurisdictions, but from where I am - this has NO legal binding whatsoever. We have those gov issued digital, invisible signatures for that, embedded in our personal ID card. Whatever is properly signed with digital signature, the printed out page bears no legal force. Anyway, businesses still like to do it this way ("Signing" pdf by applying some pixels). I wonder if it is just an inconveni…

I'm in the US and as far as I know, a digital signature is completely valid. [edit: ~it's the same way here.~ Misinterpreted parent comment.] Yet Ford repeatedly insisted I print out the documents, sign them, and scan them. I tried a digital signature anyway - and they called me out on it.

"I tried a digital signature anyway"

Do you mean:

A) a cryptographic signature?

B) an image of your handwritten signature?

C) something else?

I think you and GP might be talking about different things.

Re: FalsiScan: Make it look like a PDF has been hand signed and scanned

#56
post #14

Preview on Mac OS can do this. You hold your signature up to the camera and then it creates an image you can add to any pdf.

Preview has to be one of the most under-appreciated apps on MacOS. It implements so much handy everyday functionality that requires third-party software on Windows. Or did, last time I used Windows (admittedly some time ago).

on windows i find myself bouncing around a lot between pdf viewers, choosing between lightweight but feature sparse options (sumatra) and heavier, more featured programs (acrobat, foxit)

i've never thought about replacing preview.

Re: FalsiScan: Make it look like a PDF has been hand signed and scanned

#57

What's the use case of this? Signing documents with visual signatures instead of cryptographic ones is already extremely archaic, but having to make them look like being signed by hand is absurdly so.

You’re implying that a bureaucratic process being absurd and extremely archaic means it doesn’t exist?

Re: FalsiScan: Make it look like a PDF has been hand signed and scanned

#58
post #27

Don't know about different Jurisdictions, but from where I am - this has NO legal binding whatsoever. We have those gov issued digital, invisible signatures for that, embedded in our personal ID card. Whatever is properly signed with digital signature, the printed out page bears no legal force. Anyway, businesses still like to do it this way ("Signing" pdf by applying some pixels). I wonder if it is just an inconveni…

Same here. Real signatures on paper as well as cryptographic signatures are legally binding. Pasting a picture onto a PDF isn't but nobody wants to deal with the bureaucracy so they do it anyway. Getting a cryptographic token you can use to legally sign things is such a bureaucratic nightmare too, nobody wants to do it, including myself and I really like this stuff.

Re: FalsiScan: Make it look like a PDF has been hand signed and scanned

#60
I recently learned that a cryptographic signing operation on a PDF is more or less bogus due to the complexity of the format. Every once in a while some researchers take a look and find a bunch of new ways to forge such things. I guess the root problem is that you end up signing a whole whack of stuff that you don't see or understand. That isn't ever going to work. I think that in practice you can only sign plain text if you want it to be secure.

So this really isn't any worse than the alternatives, at least for PDFs...

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