PDF Explained

Chapter 2. Building a Simple PDF

In this chapter, we’ll build PDF content manually in a text editor. Then we’ll use the free pdftk program to turn it into a valid PDF file and look at the output in a PDF viewer.

This example, together with all the PDF files in this book, can be downloaded from the web page for this book.

We’ll be looking at a lot of new concepts all at once, so don’t worry if it seems overwhelming—we’ll come back to all of this in future chapters.

pdftk—The PDF Toolkit

pdftk is a free, open source command-line tool for Microsoft Windows, Mac OS X, and Unix. We’re going to use it in this chapter (and throughout this book) to turn PDF content we’ve written in a text editor into a valid PDF file. pdftk can also be used to:

Merge and split PDF documents

Rotate PDF pages

Decrypt and encrypt

Fill PDF forms with data

Apply watermarks and stamps

Print and change PDF metadata

Attach files to PDF documents

Source and binary packages for pdftk can be found at PDF Labs.

The creator of pdftk, Sid Steward, is also the author of O’Reilly’s PDF Hacks—a selection of tools and tips for working with PDF.

Basic PDF Syntax

A PDF file contains at least three distinct languages:

• The document content, which is a number of objects with links between them forming a directed graph. These objects describe the structure of the document (pages, metadata, fonts, and resources).

• The page content, described using a series of operators for placing text and graphics on a single page.

• The file structure, consisting ...