RE: Mickey Mouse

From: Anshuman Razdan (razdan@gloo3d.com)
Date: Tue Feb 20 2001 - 05:40:13 EET


Steve et al.
        There is no robust method to watermarking STL files. Unlike 2D Images where
lower bits can be used to embed a signal without destroying the image, in 3D
a) one loses accuracy and b) the problem is that almost all of the
watermarking techniques can be defeated by retriangulation.

        3D as you know has geometry and topology where as 2D images have implied
topology (i.e. i-1,j the pixel will be next to i,j pixel) and just geometry
(intensity, color, etc.). So a 3D object (for lack of a better term) can be
retriangulated without changing the geometry of the object i.e. changing the
topology. For example lets say u have a rectangle (in 3D altho a rectangle
is planar and 2Dish but bear with me for a moment). Now it has one diagonal
connoted such that there are two triangles. Now one can just switch the
diagonal, maintain the same geometry and alter the topology.

        Watermarking algorithms rely on topology and few of them are robust when it
comes to scaling, rotation (etc. transformations) not breaking them. There
have been some papers (and great interest) in this area but the final word
has not been written yet.

AR
Dr Anshuman Razdan,
Director PRISM
MC 5906, GWC 574
Arizona State University
Tempe AZ 85287
http://prism.asu.edu/~razdan
480 965 0483 (Tina)

>> -----Original Message-----
>> From: owner-rp-ml@ltk.hut.fi
>> [mailto:owner-rp-ml@ltk.hut.fi]On Behalf Of
>> Steven Adler
>> Sent: Monday, February 19, 2001 2:52 PM
>> To: rp-ml@bart.lpt.fi; Paul Finelt - Optimum Online
>> Subject: Re: Mickey Mouse
>>
>>
>> Thank you Paul...... I was thinking the same thing. Is there
>> a method to
>> "watermark" or "copyright" an STL file......?
>>
>> Why not incorporate a disclosure statement on opening
>> "watermarked" STL
>> files advising copyrights.....?
>>
>> Steven Adler CEO
>> Automated 3D Modeling
>> adler@a3dm.com
>> www.a3dm.com
>> ----- Original Message -----
>> From: "Paul Finelt - Optimum Online" <finelt@optonline.net>
>> To: <A.gerrits@ind.tno.nl>; <rp-ml@bart.lpt.fi>
>> Sent: Monday, February 19, 2001 4:53 PM
>> Subject: RE: Mickey Mouse
>>
>>
>> > Anyone supplying an STL of Mickey Mouse or any other copywritten or
>> > trademarked likeness of any character.....
>> >
>> > Don't send these things around. Disney and other owners of these
>> properties
>> > will sue you or at least make your life miserable for a
>> period of time.
>> >
>> > Even if you think you're just using it for your own
>> purposes. These are
>> > commercial entities with substantial value. The owners of
>> these guys are
>> > serious.
>> >
>> > I know some people that have found out the hard way.
>> >
>> >
>> > -----Original Message-----
>> > From: owner-rp-ml@ltk.hut.fi
[mailto:owner-rp-ml@ltk.hut.fi]On Behalf Of
> A.gerrits@ind.tno.nl
> Sent: Monday, February 19, 2001 8:49 AM
> To: rp-ml@ltk.hut.fi
> Subject: Mickey Mouse
>
>
> Dear rapid people,
>
> Who has an STL file of Mickey ??
> We want to thank a good relation who would go crazy with a nice prototype.
>
> Thanks in advance for your help.
>
> Best regards,
>
> Anton Gerrits
>
> TNO Industrial Technology
> Department Industrial Prototyping
> De Rondom 1, P.O. Box 6235, 5600 HE Eindhoven (The
> Netherlands)
> Telephone (+31) 040-26 50 608, fax (+31) 040-26 50 678
> Mobile (+31) 06-23 11 53 97
> E-mail a.gerrits@ind.tno.nl <mailto:a.gerrits@ind.tno.nl>
> Look also at
> http://www.ind.tno.nl/en/productiondevelopment/prototyping/index.html
> <http://www.ind.tno.nl/en/productiondevelopment/prototyping/index.html>
>
> For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/
>
>
> For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/
>

For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/

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