I am trying to read the text content of a pdf file into a Perl variable. From other SO questions/answers I get the sense that I need to use CAM::PDF. Here's my code:
#!/usr/bin/perl -w
use CAM::PDF;
my $pdf = CAM::PDF->new('1950-01-01.pdf');
print $pdf->numPages(), " pages\n\n";
my $text = $pdf->getPageText(1);
print $text, "\n";
I tried running this on this pdf file. There are no errors reported by Perl. The first print statement works; it prints "2 pages" which is the correct number of pages in this document.
The next print statement does not return anything readable. Here's what the output looks like in Emacs:
2 pages
^A^B^C^D^E^C^F^D^G^H
^D^A^K^L^C^M^D^N^C^M^O^D^P^C^Q^Q^C ^D^R^K^M^O^D ^A^B^C^D^E
^F^G^G^H^E
^K^L
^M^N^E^O^P^E^O^Q^R^S^E
.... more lines with similar codes ....
Is there something I can do to make this work? I don't understand pdf files too well, but I thought that because I can easily copy and paste the text from the PDF file using Acrobat, it must be recognized as text and not an image, so I hoped this meant I could extract it with Perl.
Any guidance would be much appreciated.
PDFs can have different kinds of content. A PDF may not have any readable text at all, only bitmaps and graphical content, for example. The PDF you linked to, has compressed data in it. Open it with a text editor, and you will see that the content is in a "/Filter/FlateDecode" block. Perhaps CAM::PDF doesn't support that. Google FlateDecode for a few ideas.
Looking further into that PDF, i see that it also uses embedded subsets of fonts, with custom encodings. Even if CAM::PDF handles the compression, the custom encoding may be what's throwing it off. This may help: Web page from a software company, describing the problem
I'm fairly certain that the issue isn't with your perl code, it is with the PDF file. I ran the same script on one of my own PDF files, and it works just fine.
Related
I have a relatively complex Perl program that manages various pages and resources for my sites. Somewhere along the line I messed up something in a library of several thousand lines that provides essential services to most of the different scripts for the system so that scripts within my codebase that output PDF or PNG files no longer can output those files validly. If I rewrite the scripts that do the output to avoid using that library, they work, but I'd like to figure out what I broke within my library that is causing it to hurt binary output.
For example, in one snippet of code, I open a PDF file (or any sort of file -- it detects the mime type automatically) and then print it directly:
#Figure out MIME type.
use File::MimeInfo::Magic;
$mimeType = mimetype($filename);
my $fileData;
open (resource, $filename);
foreach my $self (<resource>) { $fileData .= $self; }
close (resource);
print "Content-type: " . $mimeType . "\n\n";
print $fileData;
exit;
This worked great, but at some point while editing the suspect library I mentioned, I did something that broke it and I'm stumped as to what I did. I had been playing with different utf8 encoding functions, but as far as I can tell, I removed all of my experimental code and the problem remains. Merely loading that library, without calling any of its functions, breaks the script's ability to output the file.
The output is actually being corrupted visibly, if I open it in a text editor. If I compare the source file that is opened by the code given above and the output, the source file and the output file have many differences despite there being no processing in the code above before output (those links are to a sample PDF that was run through the broken code).
I've tried retracing my steps for days and cannot find what is wrong in the problematic library -- I hadn't used this function in awhile and I wrote a lot of new code since I last tested it, so it is hard to know precisely where the problem is. My hope is someone may be able to look at the corrupted output file in comparison to the source file and at least point me in the direction of what I should be looking for that could cause such a result. I feel like I'm looking for a needle in the haystack.
I am working on a file upload system that also parses the files that are uploaded and generates another file based on info inside the file uploaded. The files being uploaded as XML files. I only need to parse the first XML tag in each file and only need to get the value of the single attribute in the tag.
Sample XML:
<LAB title="lab title goes here">...</LAB>
I am looking for a good way of extracting the value of the title attribute using the Perl split function or using Regex. I would use a Perl XML parser if I had the ability to install Perl modules on the server I am hosting my code on, however I do not have that ability.
This XML is located in an XML file, that I am opening and then attempting to parse out the attribute value. I have tried using both Split and Regex to no luck. However, I am not very familiar with Perl or regular expressions.
This is he basic outline my code so far:
open(LAB, "<", "path-to-file-goes-here") or die "Unable to open lab.\n";
foreach my $line (<LAB>) {
my #pieces = split(/"(.*)"/, $line);
foreach my $piece (#pieces) {
print "$piece\n";
}
}
I have tried using split to match against title alone using
/title/
Or match against the = character or the " character using
/\=/ or /\"/
I have also tried doing similar things using regex and have had no luck as well. I am not sure if I am just not using the proper expression or if this is not possible using split/regex. Any help on the matter would be much appreciated, as I am admittedly a novice at Perl still. If this type of question has been answered elsewhere, I apologize. I did some searching and could not find a solution. Most threads suggest using an XML parsing Perl module, which I would if I had the privileges to install them.
"But I can't use CPAN" is a quick way to get yourself downvoted on the Perl tag (though it wasn't I who did so). There are many ways that you can use CPAN, even if you don't have root. In fact you can have your own Perl even if you don't have root. While I highly recommend some of those options, for now, the easiest way to do this is just to download some Pure Perl modules, and included them in your codebase. Mojolicious has a very small, but very useful XML/DOM parser called Mojo::DOM which is a likely candidate for this kind of process.
I want to create a PDF file using zend_pdf. But this way seems not efficient at all because I need to define the exact text location :(
$page->drawText(""Some text", $x, $y);
Is there any easier way to print text?
As far as I know I don't think that there is an easy way to print a PDF with Zend_Pdf because you have to position everything.
For printing PDF in PHP, I always used TCPDF and converted HTML to PDF with great results. Unless you are forced to use Zend_Pdf I think you should avoid it. (I used the 1.11 version so things might change).
I am using Perl for automation for report generation. Reports are generated in HTML. same report can be opened in MS word format. tables generated in HTML look good in Word too.
Problem:
Ineed to also insert few graphs in the report. For HTML, I am using SVG::TT::Graph::Line Perl module to generate the graphs.
The idea here is to keep single HTML file that contains all tables and graphs.
Currently every thing looks good in HTML. but when i open the same file in Word, the graphs are replaced by data (because I am using SVG Perl module).
Just wondering what would be the best way to generate graphs for Word file that doesn't change my code much.
Any suggestions with the Perl modules to be used would be much appreciated.
I haven't tried this, but the only thing I can think of is to use ImageMagick to convert the SVG to PNG and then use a Data URI to embed the image in the HTML.
Does anyone know of a free Perl program (command line preferable), module, or anyway to search and replace text in a PDF file without using it like an editor.
Basically I want to write a program (in Perl preferably) to automate replacing certain words (e.g. our old address) in a few hundred PDF files. I could use any program that supports command line arguments. I know there are many modules on CPAN that manipulate or create pdfs but they don't have (that I've seen) any sort of simple search and replace.
Thanks in advance for any and all advice!!!
Take a look at CAM::PDF. More specifically the changeString method.
How did you generate those PDFs in the first place? Search-and-replace in the original sources and re-generate PDFs seems to be more viable. Direct editing PDFs can be very difficult, and I'm not aware of any free tools that can do it easily.