First of all, thanks for your answer.
As I need some automatic process, I might try some regex to find the info but I wonder if there isn't a more appropriate way to get this info. I.e., some code (possibly postscript) that would get this info from the PDF file.
As far as I know there are binary postscript files, aren't there binary PDF files? If this is true, the regex solution wouldn't work for the binary ones, I believe.
Rodrigo Severo