STL watermark can be changed without password

Aspose.3D App Product Family
1

I have some STL-files that I have watermarked with text and password a few months ago. I now wanted to change the watermark text and noticed that this can be done even without the password. If the watermark can be changed (and effectively deleted), this defeats the purpose of a watermark. Is this feature broken or is it supposed to be like this?

2

@Jolsen

Could you please share one of such source files? We’ll investigate this scenario at our end.

3

@Jolsen
Aspose.3D is not the only vendor can make blind watermark on 3D meshes in the Internet, if we do not allow user to reapply watermark on meshes that already have one, the other implementations can still ignore the watermark planted by Aspose, that makes this extra check meaningless.

4

I tried it again with a new file. I added some watermark text to it and used password “abc”. I then verified that the watermark was set. If I then add a new watermark to the already watermarked file, the password-protected watermark is deleted.

Here is the file with the password-protected watermark added: model with watermark

I have been sharing some copyrighted STL-files with product testers, and have watermarked them with my name and who I have shared them with. This is to discourage them from sharing the files with anyone else. If I find them floating around, I was hoping to be able to reveal the watermark text with the password, both to prove that I am the copyright holder, and to identify anyone who has wrongfully shared the files. But if anyone can overwrite an existing watermark, they could simply put a new one with their name as copyright holder.

5

@Jolsen
We understand your concern. We can add additional watermark checking, but it’s important to note that people who steal your files can still use other tools to override or remove the watermark.

6

I see. I initially tried a different watermark service. I don’t remember which, but I think they stated that their watermark could not be erased. That service didn’t work at all at the time, so that’s why I am using Aspose. Can you mention some other services?

7

@Jolsen
I’ve created a ticket THREEDNET-1550 to improve our watermark, like permanent(unable to modify), or password checking before apply new watermark.
Some other Aspose products may also provide similar feature, I’ll coordinate with them to make sure we’ll not override watermark generated by our different products.