highlight words by regex in pdf files using python

[Peng Yu]

I don't find a general pdf library in python that can do any
operations on pdfs.

I want to automatically highlight certain words (using regex) in a
pdf. Could somebody let me know if there is a tool to do so in python?

 

[Aahz]

I don't find a general pdf library in python that can do any
operations on pdfs.

I want to automatically highlight certain words (using regex) in a
pdf. Could somebody let me know if there is a tool to do so in python?

Did you Google at all? "python pdf" finds this as the first link, though
I have no clue whether it does what you want:

http://pybrary.net/pyPdf/
--
Aahz ([email protected]) <*> http://www.pythoncraft.com/

"Many customs in this life persist because they ease friction and promote
productivity as a result of universal agreement, and whether they are
precisely the optimal choices is much less important." --Henry Spencer

 

[Patrick Maupin]

I don't find a general pdf library in python that can do any
operations on pdfs.

I want to automatically highlight certain words (using regex) in a
pdf. Could somebody let me know if there is a tool to do so in python?

The problem with PDFs is that they can be quite complicated. There is
the outer container structure, which isn't too bad (unless the
document author applied encryption or fancy multi-object compression),
but then inside the graphics elements, things could be stored as
regular ASCII, or as fancy indexes into font-specific tables. Not
rocket science, but the only industrial-strength solution for this is
probably reportlab's pagecatcher.

I have a library which works (primarily with the outer container) for
reading and writing, called pdfrw. I also maintain a list of other
PDF tools at http://code.google.com/p/pdfrw/wiki/OtherLibraries It
may be that pdfminer (link on that page) will do what you want -- it
is certainly trying to be complete as a PDF reader. But I've never
personally used pdfminer.

One of my pdfrw examples at http://code.google.com/p/pdfrw/wiki/ExampleTools
will read in preexisting PDFs and write them out to a reportlab
canvas. This works quite well on a few very simple ASCII PDFs, but
the font handling needs a lot of work and probably won't work at all
right now on unicode. (But if you wanted to improve it, I certainly
would accept patches or give you commit rights!)

That pdfrw example does graphics reasonably well. I was actually
going down that path for getting better vector graphics into rst2pdf
(both uniconvertor and svglib were broken for my purposes), but then I
realized that the PDF spec allows you to include a page from another
PDF quite easily (the spec calls it a form xObject), so you don't
actually need to parse down into the graphics stream for that. So,
right now, the best way to do vector graphics with rst2pdf is either
to give it a preexisting PDF (which it passes off to pdfrw for
conversion into a form xObject), or to give it a .svg file and invoke
it with -e inkscape, and then it will use inkscape to convert the svg
to a pdf and then go through the same path.

HTH,
Pat

 

[Peng Yu]

The problem with PDFs is that they can be quite complicated.  There is
the outer container structure, which isn't too bad (unless the
document author applied encryption or fancy multi-object compression),
but then inside the graphics elements, things could be stored as
regular ASCII, or as fancy indexes into font-specific tables.  Not
rocket science, but the only industrial-strength solution for this is
probably reportlab's pagecatcher.

I have a library which works (primarily with the outer container) for
reading and writing, called pdfrw.  I also maintain a list of other
PDF tools at http://code.google.com/p/pdfrw/wiki/OtherLibraries  It
may be that pdfminer (link on that page) will do what you want -- it
is certainly trying to be complete as a PDF reader.  But I've never
personally used pdfminer.

One of my pdfrw examples at http://code.google.com/p/pdfrw/wiki/ExampleTools
will read in preexisting PDFs and write them out to a reportlab
canvas.  This works quite well on a few very simple ASCII PDFs, but
the font handling needs a lot of work and probably won't work at all
right now on unicode.  (But if you wanted to improve it, I certainly
would accept patches or give you commit rights!)

That pdfrw example does graphics reasonably well.  I was actually
going down that path for getting better vector graphics into rst2pdf
(both uniconvertor and svglib were broken for my purposes), but then I
realized that the PDF spec allows you to include a page from another
PDF quite easily (the spec calls it a form xObject), so you don't
actually need to parse down into the graphics stream for that.  So,
right now, the best way to do vector graphics with rst2pdf is either
to give it a preexisting PDF (which it passes off to pdfrw for
conversion into a form xObject), or to give it a .svg file and invoke
it with -e inkscape, and then it will use inkscape to convert the svg
to a pdf and then go through the same path.

Thank you for your long reply! But I'm not sure if you get my question or not.

Acrobat can highlight certain words in pdfs. I could add notes to the
highlighted words as well. However, I find that I frequently end up
with highlighting some words that can be expressed by a regular
expression.

To improve my productivity, I don't want do this manually in Acrobat
but rather do it in an automatic way, if there is such a tool
available. People in reportlab mailing list said this is not possible
with reportlab. And I don't see PyPDF can do this. If you know there
is an API to for this purpose, please let me know. Thank you!

Regards,
Peng

 

[Patrick Maupin]

Thank you for your long reply! But I'm not sure if you get my question or not.

Acrobat can highlight certain words in pdfs. I could add notes to the
highlighted words as well. However, I find that I frequently end up
with highlighting some words that can be expressed by a regular
expression.

To improve my productivity, I don't want do this manually in Acrobat
but rather do it in an automatic way, if there is such a tool
available. People in reportlab mailing list said this is not possible
with reportlab. And I don't see PyPDF can do this. If you know there
is an API to for this purpose, please let me know. Thank you!

I do not know of any API specific to this purpose, no. But I
mentioned three libraries (pagecatcher, pdfminer, and pdfrw) that are
capable, to a greater or lesser extent, of reading in PDFs and giving
you the data from them, which you can then do your replacement on and
then write back out. I would imagine this would be a piece of cake
with pagecatcher. (I noticed you just posted on the reportlab mailing
list, but you did not specifically mention pagecatcher.) It will
probably take more work with either of the other two. It is probable
that none of them do exactly what you want, but also that any of them
is a better starting point than coding what you want from scratch.

Regards,
Pat

 

[David Boddie]

Did you Google at all? "python pdf" finds this as the first link, though
I have no clue whether it does what you want:

http://pybrary.net/pyPdf/

The original poster might also be interested in displaying the highlighted
words without modifying the original file. In which case, the Poppler
library is worth investigating:

http://poppler.freedesktop.org/

David

 

[TP]

Thank you for your long reply! But I'm not sure if you get my question or not.

Acrobat can highlight certain words in pdfs. I could add notes to the
highlighted words as well. However, I find that I frequently end up
with highlighting some words that can be expressed by a regular
expression.

To improve my productivity, I don't want do this manually in Acrobat
but rather do it in an automatic way, if there is such a tool
available. People in reportlab mailing list said this is not possible
with reportlab. And I don't see PyPDF can do this. If you know there
is an API to for this purpose, please let me know. Thank you!

Regards,
Peng

Take a look at the Acrobat SDK
(http://www.adobe.com/devnet/acrobat/?view=downloads). In particular
see the Acrobat Interapplication Communication information at
http://www.adobe.com/devnet/acrobat/interapplication_communication.html.

"Spell-checking a document" shows how to spell check a PDF using
visual basic at
http://livedocs.adobe.com/acrobat_s...LHelp&file=IAC_DevApp_OLE_Support.100.17.html

"Working with annotations" shows how to add an annotation with visual
basic at http://livedocs.adobe.com/acrobat_s...LHelp&file=IAC_DevApp_OLE_Support.100.16.html.

Presumably combining the two examples with Python's win32com should
allow you to do what you want.