How to edit PDF files

The following types of changes to a PDF file are discussed on this page:

• How to edit text in a PDF
• How to edit an image in a PDF file
• How to delete pages, change their order or rotate them
• How to merge pages from separate PDF files
• How to convert a PDF from color to black&white

At the bottom is also a small overview of other applications that allows you to alter a PDF file.

Always keep in mind that PDF files are an accurate representation of a document. They are meant for output or on-screen viewing. They are not intended to be intermediate files that can still be edited. There are programs on the market that allow you to change the content of a PDF file and there are applications or plug-ins that can extract the content of a PDF so that you can insert this data into a new document. Altering PDF files is a last resort - whenever possible the original source file should be corrected and a new PDF generated. This is especially true for documents that will be reused at a later date!

How to edit text in a PDF

Within a PDF file text is essentially stored as single lines. The concept of text flowing from one line to another within a column does not exist. This makes it fairly difficult to edit text unless you rely on special tools that somehow manage to intelligently predict how text flows within a document

• Adobe Acrobat & Acrobat Professional have a TouchUp Text tool for small text modifications. When you add or delete text, it will not reflow the text in the entire column. Some releases of Acrobat have a pretty bad reputation when it comes to the TouchUp Text tool, with users reporting weird behavior of the edited or remaining text once the tool is used. Use this tool only if there is no way to edit the original source file and  recreate a PDF.
• Even though Adobe Illustrator can open a surprisingly large range of PDF files, it is a bad choice if you want to edit text. Illustrator automatically uses its own fonts instead of fonts embedded in a PDF. This can lead to text reflows even if you leave text untouched.
• For extensive text editing, the best application that I know is the Infix PDF Editor. I used this to add text to a book. The reflow capabilities of this application are awesome.

How to edit an image in a PDF file

There are several high-end tools on the market that are optimized for this type of task. It is however surprising how much you can already achieve with Adobe Acrobat, provided you also have applications like Photoshop and Illustrator. In the “Touchup” Preferences of Acrobat you can define which image and object editor you want to use from within Acrobat. Once this has been defined, you can use the Touchup Object Tool to select an object, context-click it and select the Edit option. In the case of an image, the default application (Photoshop on my set-up) opens the image. After changing the image, it is re-embedded in the PDF file.

Acrobat 8 Touchup Object Tool (far right)

How to delete pages, change their order or rotate them

Adobe Acrobat can do all of this but there are most likely cheaper solutions around. I never bothered to check.

How to merge pages from separate PDF files

There is a separate page on this site dedicated to this topic.

How to convert a PDF from color to black&white

There are some Acrobat plug-ins that can do this. I have used PitStop but prefer Quite-a-box-of-tricks which seems to be both faster and more reliable (in the past PitStop sometimes left some objects untouched).

PDF editing tools

Below is a short summary of the various types of software that are available on the market to edit PDF files.

• Adobe Acrobat (Professional) can be used to both view and manipulate PDF files. Next to the basic function discussed above, it can be used to completely repurpose PDF files (add multimedia elements like sound and video, add clickable buttons,…).

• Plug-ins can be installed in Acrobat Professional to enhance its ability to edit objects within PDF document. The most well-known one is probably PitStop Professional from Enfocus.
• Even though Adobe carefully avoid positioning Adobe Illustrator as a PDF editor, a remarkable number of PDF files can be opened and modified in Illustrator. Its major weakness spot is text handling.

• There are a number of stand-alone applications on the market that can be used to edit PDF files. Google is your friend :-)  Applications that I have gotten positive feedback about are:
  • Enfocus offer Neo, a stand-alone PDF editor that is a lot faster than working in Acrobat. This b4print discussion is about this product.
    Oris PDF Tuner is another alternative solution that seems to have a good reputation.
  • Companies who make their money processing PDF files, such as newspapers who need to be able to make small modifications to advertisements, often use the products of OneVision to edit PDF files. These are probably the most powerful editors on the market, with a matching price tag.
  • Recosoft created an interesting plug-in, named PDF2ID, which can convert a PDF file into an InDesign publication. This tool is discussed in this thread on the b4print forums.