Re: Disable copy and paste

[Walter van Holst]

On 8 aug. 2013, at 10:17, Rilke Rainer Michael ri...@wiso.uni-koeln.de wrote:

 Hi List,
  
 I want to export a lyx document to a pdf. However, I want also that once 
 reading the document it is impossible to copy and paste text from this pdf. 
 Do you have any idea, whether there is a workaround for lyx?
  

Basically you want DRM. Which is silly at best.

Re: Disable copy and paste

[Ray Rashif]

On 8 August 2013 16:17, Rilke Rainer Michael ri...@wiso.uni-koeln.de wrote:
 Hi List,



 I want to export a lyx document to a pdf. However, I want also that once
 reading the document it is impossible to copy and paste text from this pdf.
 Do you have any idea, whether there is a workaround for lyx?

That is encryption. You have the choice of disabling printing as well.
Converting to images, or rasterizing fonts, has the same effect as not
allowing copies but greatly increases the file size. However, this is
a standalone process, separate from LyX. I use PDFtk on GNU/Linux. [1]

[1] http://www.pdflabs.com/docs/pdftk-cli-examples/


--
GPG/PGP ID: C0711BF1

Re: Disable copy and paste

[Rainer M Krug]

Ray Rashif schivmeis...@gmail.com writes:

 On 8 August 2013 16:17, Rilke Rainer Michael ri...@wiso.uni-koeln.de wrote:
 Hi List,



 I want to export a lyx document to a pdf. However, I want also that once
 reading the document it is impossible to copy and paste text from this pdf.
 Do you have any idea, whether there is a workaround for lyx?

Just one word of caution: if you can see the text on screen, you can
extract it by taking a screenshot and using ocr (optical character
recognition) and nothing will stop you. So this just makes it slightly
more difficult to get the text.

As far as I remember, one can also convert the pdf to images, and do the
ocr automatically. Same with images - if they can be displayed, they can
be extracted.


 That is encryption. You have the choice of disabling printing as well.
 Converting to images, or rasterizing fonts, has the same effect as not
 allowing copies but greatly increases the file size. However, this is
 a standalone process, separate from LyX. I use PDFtk on GNU/Linux. [1]


pdftk is an excellent tool for doing this. You could even add it as a
copier into lyx to automatically encrypt - if you really want to.

Cheers,

Rainer


 [1] http://www.pdflabs.com/docs/pdftk-cli-examples/


 --
 GPG/PGP ID: C0711BF1

#secure method=pgpmime mode=sign


Footnotes: 
[1]  

-- 
Rainer M. Krug

email: RMKrugatgmaildotcom

Re: Disable copy and paste

[Ray Rashif]

On 8 August 2013 17:51, Rainer M Krug rai...@krugs.de wrote:
 Just one word of caution: if you can see the text on screen, you can
 extract it by taking a screenshot and using ocr (optical character
 recognition) and nothing will stop you. So this just makes it slightly
 more difficult to get the text.

What's more, if I'm not wrong, encryption depends on the reader having
support, so you can effectively render encryption useless by using a
very old reader and PDF format. Even GhostScript lets you bypass
encryption, though not intentionally.

It's really all about preventing frequent abuse of documents by lay
people. Someone with the intent _will_ get your text somehow or
another. There are many tools that person could employ.


--
GPG/PGP ID: C0711BF1

Re: Disable copy and paste

[Rainer M Krug]

Ray Rashif schivmeis...@gmail.com writes:

 On 8 August 2013 17:51, Rainer M Krug rai...@krugs.de wrote:
 Just one word of caution: if you can see the text on screen, you can
 extract it by taking a screenshot and using ocr (optical character
 recognition) and nothing will stop you. So this just makes it slightly
 more difficult to get the text.

 What's more, if I'm not wrong, encryption depends on the reader having
 support, so you can effectively render encryption useless by using a
 very old reader and PDF format. Even GhostScript lets you bypass
 encryption, though not intentionally.

I might be wrong, but I think even okular had an option (!) to enable or
disable to respect the restrictions.


 It's really all about preventing frequent abuse of documents by lay
 people. Someone with the intent _will_ get your text somehow or
 another. There are many tools that person could employ.

Absolutely - but I think the problem are not the lay people, but rather
the expert copier who knows how to do it.

Cheers,

Rainer



 --
 GPG/PGP ID: C0711BF1



-- 
Rainer M. Krug

email: RMKrugatgmaildotcom

Re: Disable copy and paste

[Richard Heck]

On 08/08/2013 06:31 AM, Rainer M Krug wrote:

Ray Rashif schivmeis...@gmail.com writes:


On 8 August 2013 17:51, Rainer M Krug rai...@krugs.de wrote:

Just one word of caution: if you can see the text on screen, you can
extract it by taking a screenshot and using ocr (optical character
recognition) and nothing will stop you. So this just makes it slightly
more difficult to get the text.

What's more, if I'm not wrong, encryption depends on the reader having
support, so you can effectively render encryption useless by using a
very old reader and PDF format. Even GhostScript lets you bypass
encryption, though not intentionally.

I might be wrong, but I think even okular had an option (!) to enable or
disable to respect the restrictions.


Yes, that was true at one point. And I assume if one complied the source
oneself, one could pretty easily disable encryption.

Richard

Re: Disable copy and paste

[Walter van Holst]

On 8 aug. 2013, at 10:17, Rilke Rainer Michael ri...@wiso.uni-koeln.de wrote:

 Hi List,
  
 I want to export a lyx document to a pdf. However, I want also that once 
 reading the document it is impossible to copy and paste text from this pdf. 
 Do you have any idea, whether there is a workaround for lyx?
  

Basically you want DRM. Which is silly at best.

Re: Disable copy and paste

[Ray Rashif]

On 8 August 2013 16:17, Rilke Rainer Michael ri...@wiso.uni-koeln.de wrote:
 Hi List,



 I want to export a lyx document to a pdf. However, I want also that once
 reading the document it is impossible to copy and paste text from this pdf.
 Do you have any idea, whether there is a workaround for lyx?

That is encryption. You have the choice of disabling printing as well.
Converting to images, or rasterizing fonts, has the same effect as not
allowing copies but greatly increases the file size. However, this is
a standalone process, separate from LyX. I use PDFtk on GNU/Linux. [1]

[1] http://www.pdflabs.com/docs/pdftk-cli-examples/


--
GPG/PGP ID: C0711BF1

Re: Disable copy and paste

[Rainer M Krug]

Ray Rashif schivmeis...@gmail.com writes:

 On 8 August 2013 16:17, Rilke Rainer Michael ri...@wiso.uni-koeln.de wrote:
 Hi List,



 I want to export a lyx document to a pdf. However, I want also that once
 reading the document it is impossible to copy and paste text from this pdf.
 Do you have any idea, whether there is a workaround for lyx?

Just one word of caution: if you can see the text on screen, you can
extract it by taking a screenshot and using ocr (optical character
recognition) and nothing will stop you. So this just makes it slightly
more difficult to get the text.

As far as I remember, one can also convert the pdf to images, and do the
ocr automatically. Same with images - if they can be displayed, they can
be extracted.


 That is encryption. You have the choice of disabling printing as well.
 Converting to images, or rasterizing fonts, has the same effect as not
 allowing copies but greatly increases the file size. However, this is
 a standalone process, separate from LyX. I use PDFtk on GNU/Linux. [1]


pdftk is an excellent tool for doing this. You could even add it as a
copier into lyx to automatically encrypt - if you really want to.

Cheers,

Rainer


 [1] http://www.pdflabs.com/docs/pdftk-cli-examples/


 --
 GPG/PGP ID: C0711BF1

#secure method=pgpmime mode=sign


Footnotes: 
[1]  

-- 
Rainer M. Krug

email: RMKrugatgmaildotcom

Re: Disable copy and paste

[Ray Rashif]

On 8 August 2013 17:51, Rainer M Krug rai...@krugs.de wrote:
 Just one word of caution: if you can see the text on screen, you can
 extract it by taking a screenshot and using ocr (optical character
 recognition) and nothing will stop you. So this just makes it slightly
 more difficult to get the text.

What's more, if I'm not wrong, encryption depends on the reader having
support, so you can effectively render encryption useless by using a
very old reader and PDF format. Even GhostScript lets you bypass
encryption, though not intentionally.

It's really all about preventing frequent abuse of documents by lay
people. Someone with the intent _will_ get your text somehow or
another. There are many tools that person could employ.


--
GPG/PGP ID: C0711BF1

Re: Disable copy and paste

[Rainer M Krug]

Ray Rashif schivmeis...@gmail.com writes:

 On 8 August 2013 17:51, Rainer M Krug rai...@krugs.de wrote:
 Just one word of caution: if you can see the text on screen, you can
 extract it by taking a screenshot and using ocr (optical character
 recognition) and nothing will stop you. So this just makes it slightly
 more difficult to get the text.

 What's more, if I'm not wrong, encryption depends on the reader having
 support, so you can effectively render encryption useless by using a
 very old reader and PDF format. Even GhostScript lets you bypass
 encryption, though not intentionally.

I might be wrong, but I think even okular had an option (!) to enable or
disable to respect the restrictions.


 It's really all about preventing frequent abuse of documents by lay
 people. Someone with the intent _will_ get your text somehow or
 another. There are many tools that person could employ.

Absolutely - but I think the problem are not the lay people, but rather
the expert copier who knows how to do it.

Cheers,

Rainer



 --
 GPG/PGP ID: C0711BF1



-- 
Rainer M. Krug

email: RMKrugatgmaildotcom

Re: Disable copy and paste

[Richard Heck]

On 08/08/2013 06:31 AM, Rainer M Krug wrote:

Ray Rashif schivmeis...@gmail.com writes:


On 8 August 2013 17:51, Rainer M Krug rai...@krugs.de wrote:

Just one word of caution: if you can see the text on screen, you can
extract it by taking a screenshot and using ocr (optical character
recognition) and nothing will stop you. So this just makes it slightly
more difficult to get the text.

What's more, if I'm not wrong, encryption depends on the reader having
support, so you can effectively render encryption useless by using a
very old reader and PDF format. Even GhostScript lets you bypass
encryption, though not intentionally.

I might be wrong, but I think even okular had an option (!) to enable or
disable to respect the restrictions.


Yes, that was true at one point. And I assume if one complied the source
oneself, one could pretty easily disable encryption.

Richard

Re: Disable copy and paste

[Walter van Holst]

On 8 aug. 2013, at 10:17, Rilke Rainer Michael  wrote:

> Hi List,
>  
> I want to export a lyx document to a pdf. However, I want also that once 
> reading the document it is impossible to copy and paste text from this pdf. 
> Do you have any idea, whether there is a workaround for lyx?
>  

Basically you want DRM. Which is silly at best.

Re: Disable copy and paste

[Ray Rashif]

On 8 August 2013 16:17, Rilke Rainer Michael  wrote:
> Hi List,
>
>
>
> I want to export a lyx document to a pdf. However, I want also that once
> reading the document it is impossible to copy and paste text from this pdf.
> Do you have any idea, whether there is a workaround for lyx?

That is encryption. You have the choice of disabling printing as well.
Converting to images, or rasterizing fonts, has the same effect as not
allowing copies but greatly increases the file size. However, this is
a standalone process, separate from LyX. I use PDFtk on GNU/Linux. [1]

[1] http://www.pdflabs.com/docs/pdftk-cli-examples/


--
GPG/PGP ID: C0711BF1

Re: Disable copy and paste

[Rainer M Krug]

Ray Rashif  writes:

> On 8 August 2013 16:17, Rilke Rainer Michael  wrote:
>> Hi List,
>>
>>
>>
>> I want to export a lyx document to a pdf. However, I want also that once
>> reading the document it is impossible to copy and paste text from this pdf.
>> Do you have any idea, whether there is a workaround for lyx?

Just one word of caution: if you can see the text on screen, you can
extract it by taking a screenshot and using ocr (optical character
recognition) and nothing will stop you. So this just makes it slightly
more difficult to get the text.

As far as I remember, one can also convert the pdf to images, and do the
ocr automatically. Same with images - if they can be displayed, they can
be extracted.

>
> That is encryption. You have the choice of disabling printing as well.
> Converting to images, or rasterizing fonts, has the same effect as not
> allowing copies but greatly increases the file size. However, this is
> a standalone process, separate from LyX. I use PDFtk on GNU/Linux. [1]
>

pdftk is an excellent tool for doing this. You could even add it as a
copier into lyx to automatically encrypt - if you really want to.

Cheers,

Rainer


> [1] http://www.pdflabs.com/docs/pdftk-cli-examples/
>
>
> --
> GPG/PGP ID: C0711BF1
>
<#secure method=pgpmime mode=sign>


Footnotes: 
[1]  

-- 
Rainer M. Krug

email: RMKruggmailcom

Re: Disable copy and paste

[Ray Rashif]

On 8 August 2013 17:51, Rainer M Krug  wrote:
> Just one word of caution: if you can see the text on screen, you can
> extract it by taking a screenshot and using ocr (optical character
> recognition) and nothing will stop you. So this just makes it slightly
> more difficult to get the text.

What's more, if I'm not wrong, encryption depends on the reader having
support, so you can effectively render encryption useless by using a
very old reader and PDF format. Even GhostScript lets you bypass
encryption, though not intentionally.

It's really all about preventing frequent abuse of documents by lay
people. Someone with the intent _will_ get your text somehow or
another. There are many tools that person could employ.


--
GPG/PGP ID: C0711BF1

Re: Disable copy and paste

[Rainer M Krug]

Ray Rashif  writes:

> On 8 August 2013 17:51, Rainer M Krug  wrote:
>> Just one word of caution: if you can see the text on screen, you can
>> extract it by taking a screenshot and using ocr (optical character
>> recognition) and nothing will stop you. So this just makes it slightly
>> more difficult to get the text.
>
> What's more, if I'm not wrong, encryption depends on the reader having
> support, so you can effectively render encryption useless by using a
> very old reader and PDF format. Even GhostScript lets you bypass
> encryption, though not intentionally.

I might be wrong, but I think even okular had an option (!) to enable or
disable to respect the restrictions.

>
> It's really all about preventing frequent abuse of documents by lay
> people. Someone with the intent _will_ get your text somehow or
> another. There are many tools that person could employ.

Absolutely - but I think the problem are not the lay people, but rather
the "expert copier" who knows how to do it.

Cheers,

Rainer

>
>
> --
> GPG/PGP ID: C0711BF1
>


-- 
Rainer M. Krug

email: RMKruggmailcom

Re: Disable copy and paste

[Richard Heck]

On 08/08/2013 06:31 AM, Rainer M Krug wrote:

Ray Rashif  writes:


On 8 August 2013 17:51, Rainer M Krug  wrote:

Just one word of caution: if you can see the text on screen, you can
extract it by taking a screenshot and using ocr (optical character
recognition) and nothing will stop you. So this just makes it slightly
more difficult to get the text.

What's more, if I'm not wrong, encryption depends on the reader having
support, so you can effectively render encryption useless by using a
very old reader and PDF format. Even GhostScript lets you bypass
encryption, though not intentionally.

I might be wrong, but I think even okular had an option (!) to enable or
disable to respect the restrictions.


Yes, that was true at one point. And I assume if one complied the source
oneself, one could pretty easily disable encryption.

Richard