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Whipyo
01-23-2006, 11:01 PM
Does anyone here actually use digital watermarks? (not to be confused with a visual watermark).

If so, have you ever had any instances where the Digimark Spider has actually found any violations of your copyright?

Do you find the subscription costs worth it?

Just wondering......

Whipyo

halo
01-24-2006, 09:51 AM
no, because they can be defeated in 2 seconds...

Whipyo
01-24-2006, 10:40 PM
no, because they can be defeated in 2 seconds...

After reading a couple of articles, it does seem pretty easy to break the watermark.

I think I'll just encrypt layered PDFs instead.

halo
01-24-2006, 11:30 PM
i seem to remember PDF security has been comprimised, but that seems like a good option for the layman.

Whipyo
01-25-2006, 01:23 AM
You can compromise the master password security easily but you will lose your layers and only have a flat file.

If you need to break the user password then there are a couple of options:

Using a password cracker (using brute-force or dictionary attacks) to find 8-character password consisting of lowercase Latin letters and digits you'll need about 50 days. Imagine if you used 20 characters.

Some PDF decryption utilities are a bit faster - Average time to decrypt (on Pentium 4/1600) - 1 week.

Hopefully no-one is that keen!

archerion
01-27-2006, 03:27 AM
yes one week if the last try was the password.. so they could get in 10 minutes if they are lucky.

Whipyo
01-27-2006, 03:36 AM
1 week was the average time...

If they were unlucky, it could take months. :D

halo
01-27-2006, 11:15 AM
interesting about losing the layers...think brute force is faster than that though...i bruted a rar file i'd somehow screwed up and it took about 2 days to find an 8 character password and that was about 3 years ago on a p800.

but a longer password would make this seem like the way to go :D

opus13
01-29-2006, 09:57 AM
Advanced eBook Processr can remove protection from a pdf without damaging its contents in seconds.

JosephGoss
02-01-2006, 05:09 PM
no, because they can be defeated in 2 seconds...

hows that?, i tried, but i had to destroy the image quite a bit, they seem hardy

halo
02-02-2006, 11:45 AM
add noise

or covert to index or 16bit (not 48)

or jpeg

etc

or anything that randomly shifts pixels around in relation to each other.

in some flat images you can actually see them and edit them.

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02-02-2006, 11:45 AM
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