Adding a watermark to a PDF file is easy in Nitro PDF, but if you want the watermark to have a transparent background, things get a little more complicated.
I wanted to add our logo to a brochure so that visitors of our scales and balances shop would have a way of telling from where they had downloaded the brochure. This particular brochure had backgrounds in several colors, which is why the logo itself needed to have a transparent background.
Unfortunately, Nitro PDF Professional does not recognize the transparent background in image files (tested with version 184.108.40.206). The watermark has to be a PDF file to have a transparent background.To make matters worse, the simple graphics editor I had used years ago to create the logo had no PDF export option.
Here’s the workaround I used:
1. Export the logo in an image format that supports transparency (I used PNG):
2. Open the image with OpenOffice Draw (open source, free download here):
3. Export as PDF:
4. In Nitro PDF, choose Insert and Edit > Watermark > Manage Watermarks & Backgrounds:
5. Create a new profile and add a PDF watermark:
6. Choose the PDF file created in step 3 and adjust the settings to place the watermark where you want it. Don’t forget to choose Open a web link under Action if you want the watermark to be clickable:
7. Apply the watermark to the document:
As you can see, it looks pretty good on a blue background, too. 😉
Note: You can move individual watermarks around using the Edit tool, but the clickable area does not seem to move with them.