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.  > 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 >  http://www.pdflabs.com/docs/pdftk-cli-examples/ > > > -- > GPG/PGP ID: C0711BF1 > <#secure method=pgpmime mode=sign> Footnotes:  -- Rainer M. Krug email: RMKrug<at>gmail<dot>com