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Apologies in advance if I misplaced this question and if it is a silly question to ask since I'm a newbie.

I want to certificate my graphics works(such as mesh models, animation, etc.,) to keep authenticity of my work.

Is there a possible way to do it? Can I digitally sign my graphics work like code signing? Can I have my own CA to do this?

If there any possibilities please let me know it

  • 2
    I think you may be looking for the term "digital watermark". – Paul Jan 16 '16 at 21:54
  • @Paul that is certainly possible but thats not what the question is asking. Verifying no tamper in transit is certainly a valid issue. From his comments looks more like he wants DRM. But that wont work. – joojaa Jan 17 '16 at 7:46
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Yes you can cryptographically sign your work or any digital file as a matter of fact. The signing only computes a hash of the file or set of files and provides a mechanism for the user to verify that the hash is same. If the hash changes then the file has been tampered with and no longer satisfies signature. The system essentially ignores file type (a file is a collection of ones and zeroes after all).

The real challenge is that is the recipient ready to check signatures. Most likely they are not. Signing a arbitrary file is somewhat pointless if your end user has no intention/capability to verify authenticity. This is a social problem and technology can not overcome this.

If you make your own CA (Certificate Authority) then the question becomes how do I exactly know you have signed it. What is to stop me from changing your file making my own CA and signing the file? This is fine if i know you and can get a certificate to authenticate you beforehand, but if not then its pointless. This is why such things as keysharing parties exist. Problem with keysharing is that the other people you want to verify the signing for must also attend some keysharing party (not going to happen in most cases), or rely on a organization much like a official CA. (you can get a free key that is widely recognized though even in the current system)

Some formats, most notably PDF have a in-built cyptographic signing facility. So you could archive your data inside the PDF file as a attachment and have a certificate of authenticity on a page describing how to use this. But again would be highly unusual. Besides most users aren't aware of such things so even if you did this i could strip it sign with another signature and most users would be blissfully happy in ignorance.

TL;DR

Simply put, you can not overcome the social problem. Technically its easily done.

  • I have another person in graphics design who is remote to me. That's why I need of a certificate between him and myself which is declared by me that states his work is authentic digitally. Does any 3D graphics tools(3ds Max) provide this internally. I do not believe that WaterMark will keep authenticity since every one knows how to remove watermarks. – Maurious Paul Jan 17 '16 at 4:55
  • @MauriousPaul No... but it could be made. Havent used max in a few years though. Anyway i fail to see why remote workers need signing why are you so concerned with a man in the middle attack. Wouldnt it just be easier for you to arrange a ssh key and iser account on a server. Why ecxactly is the authenticity important. Its not like the signing protects the work itself it jus signs it as not having been modified after the original author made the file. Ots not prptecting the work in any way. Copyprotection is impossible to do. – joojaa Jan 17 '16 at 7:38
  • Watermarking on the otherhand can not be easily removed, but watermarking only works well with bitmap/raster graphics. Note digital watermarking is there even if your eye can not see it. Anhway the only way to avoid art being tsolen is not to share it in firstplace. – joojaa Jan 17 '16 at 7:43
  • @MauriousPaul Watermaking is very very easy to remove in Photoshop/Image files unless you add the demo kind of watermark ON the image and as part of your pixels... which is probably not what you want. The watermark "signature" though is easy to remove. – go-junta Jan 19 '16 at 6:09
  • @go-junta Oh no digital rights watermarking is embedded in the fourier transform of the image itself, and its not visible to human eye. A semi translucent human readable watermark is not the same thing. Its VERY VERY hard to remove. – joojaa Jan 19 '16 at 6:39
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You can install GPG and run gpg -s your_document. You don't need to use a CA but your key can be uploaded to a key server and it will be certain that the key belongs to you if you have it signed in what is called a web of trust.

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