Count number of pages in PDF file 1

[PPettit]

Is there a quick and easy way to determine the number of pages in a PDF file?

 

[DrSeussFreak]

open it up?

 

[PPettit]

In case you didn't know where you were posting, this is the VBScript forum of Tek-Tips. Therefore, it should be relatively easy to conclude that I'm asking how to do this programmatically so that I can use the page count in some manner.


Since you haven't been a member for very long, I would suggest that you check out the posting policies for this site:

http://www.tek-tips.com/market.cfm

 

[xwb]

Assuming you already know how to open and read a binary file and search input lines for text.

1) Look for the page tree object. Search the file for /Pages
2) Search backwards for obj<< and capture everything up to >>
3) Look for the tokens. These begin with / and end with either a space, [ or another token.
4) If you have tokens /Count, /Type, /Pages, /Kids and nothing else, you have the page tree object.
5) The number after /Count is the number of pages.

For instance, if you get

obj<</Count 251/Type/Pages/Kids[...>>

there are 251 pages.

The tokens may be in any order. You could get

obj<<
   /Type /Pages
   /Kids [...]
   /Count 20
>>
endobj

on non-Adobe generated PDF. If you get /Parent in the token set, it is not the page tree object. There will be lots of these but they normally occur after the page tree object.

You can get the PDF specification from

http://www.adobe.com/devnet/pdf/pdf_reference.html

Note that there are 8 different versions but for finding out the number of pages, any one will do. Version 1.6 (for Adobe 7) is about 9Mb. Version 1.7 (for Adobe 8) is about 32Mb. I haven't looked at 1.7 yet. Probably a lot of pictures.

 

[PPettit]

Thanks, xwb. I'll look into this. It didn't even occur to me that I could search through a file this way.

I'm not a programmer by nature or trade, just a computer guy who's had to teach himself some scripting.