Copying text from a protected pdf file

[George White]

Quoting Paul Smith <phhs80 at gmail.com>:

> On 9/17/05, Paul Smith <phhs80 at gmail.com> wrote:
> > > > I have got a pdf file, whose text I would like to copy to a word
> > > > processor. However, it seems to be protected, as when I copy and paste
> > > > a piece of text from there into a word processor, I only see garbage.
> > > > Is there some way of getting clean text from the pdf file?
> > >
> > > The PDF format has many ways to display text.  To be able to extract
> text
> > > you need a file that stores strings and uses font information to render
> them
> > > in the viewer.  You may be seeing images that were rasterized long ago.
> > > You should provide the output of the "pdffonts" command, preferrable for
> a
> > > minimal document (a big document could combine sections that use fonts
> with
> > > images).
> > >
> > > For example, the simplest case is a document that uses the PostScript
> Type 1
> > > fonts provided by the viewer:
> > >
> > > $ pdffonts /usr/share/doc/cups-1.1.20/ssr.pdf
> > > name                                 type         emb sub uni object ID
> > > ------------------------------------ ------------ --- --- --- ---------
> > > Times-Roman                          Type 1       no  no  no       4  0
> > > Helvetica                            Type 1       no  no  no       7  0
> > > Helvetica-Bold                       Type 1       no  no  no       8  0
> > > Times-Bold                           Type 1       no  no  no       5  0
> > > Courier                              Type 1       no  no  no       3  0
> > > Symbol                               Type 1       no  no  no       9  0
> > > Times-Italic                         Type 1       no  no  no       6  0
> > 
> > Thanks, George. In my case,
> > 
> > $ pdffonts myfile.pdf
> > name                                 type         emb sub uni object ID
> > ------------------------------------ ------------ --- --- --- ---------
> > DTUUBE+TTBC19E318t00                 TrueType     yes yes no      13  0
> > URMVBE+TTBC18C910t00                 TrueType     yes yes no      16  0
> > TOYVBE+Symbol                        Type 1C      yes yes no      19  0
> > Helvetica                            Type 1C      yes no  no      22  0
> > CLLUBE+TTBC1802E0t00                 TrueType     yes yes no      34  0
> > Helvetica-Bold                       Type 1C      yes no  no      43  0
> > Helvetica-Oblique                    Type 1C      yes no  no      58  0
> > $
> 
> Is it possible to find the missing fonts to install them? 

Do you have a friend at the No Such Agency?

The four embedded subsets will be a problem.  When you extract text from a PDF
file you don't get encoding or font information, so even if the fonts are
installed you would have to manually assign the font to each fragment.  A
subsetted font may not use any recognizable encoding.   I have some where it
appears that the subsets are encoded starting with ASCII control-character 
codes (e.g., 0x01, 0x02, ...).  If you are dealing with normal text, you might
be dealing with a simple substitution code.  Try constructing a 
table by working with short strings from text that seems to be in the same
font.

I'm looking at a document where "off" becomes "<ACK><BEL><BEL>", so my table
would have:
 
  o -> 6
  f -> 7

-- 
George N. White III
Head of St. Margarets Bay, Nova Scotia