Question

I am currently taking a curse in C programming, and for our final project we need to read some text from a pdf into a string, so we can manipulate the string.

In essence what i am looking for is something similar to this, only with a .pdf instead of a .txt file.

  char *line;
  fscanf(myfile.txt," %[^\n]", line);

I have no experience with ghostscript, so I have no idea if this is even possible, although we where told that we should use ghostscript.

Answer 1

The current version of Ghostscript includes the ‘txtwrite’ device, which will extract text from any supported input (PostScript, PDF, XPS, PCL) and will emit it in a variety of forms.

The UTF-8 output would probably be most useful to you.

Caveat! Many things which appear to be text in PDF files are not text, and no attempt is made to deal with these.

ps2ascii is deprecated with the release of the txtwrite device, but in any case its perfectly capable (despite the name) of dealing with PDF as an input.

I can’t think why anyone assigned you this project, PDF files are not text files, and cannot be treated as such. In addition to the fact that PDF files are generally compressed, identifying the contents stream and all the other streams it relies on (which may themselves include text) is non-trivial. Plus, the text is often encoded in a way which can be difficult to understand (this is particularly true of CIDFonts and TrueType fonts).

Perhaps your tutor expected you to first become expert in the PDF format, but that seems excessive for a C course.