Re: PDF is blocked for printing, etc. OK for acroread (it behaves as expected), but KPDF allows me to print it, even if it is protected! Why?
On 19/04/2010 17:32, Merciadri Luca wrote:
> Sjoerd Hardeman wrote:
>> Pdf "anti-features" are fake security. Don't trust on them, never.
> And what do you suggest if one wants some real protection _and_ the
> benefits of a format like PDF? Thanks.
If you have free software (ie software you have the sources and are able
to recompile) and if you can get the information on the screen, then it is
only a matter of programmation to be able to have it on printer. So,
free software readers that forbid printing can be (more or less) easily
circumvented (and the patch to do this will be done and available on
internet). So why would the authors of such readers want to program this
at first time.
If you want to avoid printing, you need to fully control the whole chain
(ie TPA, ...) AND the terminals (ie, if you can show it on screen, some
classic 'print-screen-to-file' and graphical software can be used to
print the document, or even camera and image post-processing).
For now, the only domain where such restrictions works partially are
HD-DVD (and its possible it is already broken). This is possible because
it is expensive to acquire good quality video data (ie recording what
is diffused by a secure HD player on screen by a camera will have
no really good quality). This would not work for audio data (at least,
until the decoder is not embedded into brain ;-) ) because it would
be easy to reacquire good quality data from a line-out.
So, what would be the use case to allow a someone to read the information
but not print it ? In any case, printing it would be more or less convenient
but it will always be possible if it is displayed on screen (even
with Acrobat Reader)
Regards,
Vincent
--
Vincent Danjean GPG key ID 0x9D025E87 vdanjean@debian.org
GPG key fingerprint: FC95 08A6 854D DB48 4B9A 8A94 0BF7 7867 9D02 5E87
Unofficial packages: http://moais.imag.fr/membres/vincent.danjean/deb.html
APT repo: deb http://perso.debian.org/~vdanjean/debian unstable main
Reply to:
- References:
- PDF is blocked for printing, etc. OK for acroread (it behaves as expected), but KPDF allows me to print it, even if it is protected! Why?
- From: Merciadri Luca <Luca.Merciadri@student.ulg.ac.be>
- Re: PDF is blocked for printing, etc. OK for acroread (it behaves as expected), but KPDF allows me to print it, even if it is protected! Why?
- From: Neil Williams <codehelp@debian.org>
- Re: PDF is blocked for printing, etc. OK for acroread (it behaves as expected), but KPDF allows me to print it, even if it is protected! Why?
- From: Merciadri Luca <Luca.Merciadri@student.ulg.ac.be>
- Re: PDF is blocked for printing, etc. OK for acroread (it behaves as expected), but KPDF allows me to print it, even if it is protected! Why?
- From: Merciadri Luca <Luca.Merciadri@student.ulg.ac.be>