The “Perfect” watermark: a covert watermark that can be tracked on the web and a visual watermark that only appears when the image is printed.

Many customers wish there was such a product. If you take a few minutes to think about how to secure the viewing and printing environment, you start to get an idea why this is not a simple “Plug & Play” solution. It requires a secure reader and print application/plug-in that your potential customers would also have to use to view your images, but you want potential customers to view your images quickly and easily on the web.  If there was only one web browser that everyone used and it came with this “Perfect” plug-in preinstalled, this might be possible.

While we continue to look for the “Perfect” solution, I do have a work around you may want to try. You’ll need technical expertise, some time to burn and a special project that would justify the effort.  Personally I think this workflow would be too much work to produce just a few images, but if you are putting together a catalog with lots of images, this could be a process you might wish to explore.

Before we get started, this process is NOT a Digimarc product, i.e. we can’t provide support if you have trouble with creating reliable settings, don’t have the right software or some kid breaks your security a week after you post it. I’ll respond to comments on the workflow, but I will not be teaching you the applications.

That’s the disclaimer so here’s my work around solution…

You’ll need to use Adobe's Illustrator, Photoshop and Acrobat Professional; InDesign can be used instead of Illustrator. I used CS3 versions of Illustrator, Acrobat and CS4 Photoshop on a Mac. Older and newer versions of these applications may work differently, so refer to your manuals. I am assuming you’ve read the Digital Watermarking Guide, used these applications before, and are familiar enough with them that with this outline, manuals and Adobe’s online support, you can figure how to optimize this process to your workflow.

First, resize an image for posting to the web and apply the digital watermark. Save this as a non-lossy Tiff file as you don’t want to lose the watermark signal to lossy compression. Also create a visual watermark (see my March 8th blog) that’s the size needed for this file and save it as a Tiff as well.

Next, place the watermarked Tiff into Illustrator, add a second layer and place the visual watermark on top. I set the visual watermark’s transparency to multiply.

Now save the file as a PDF using maximum image quality JPEG, with no re-sampling of the images since they are already at the correct size for the web; and most importantly I make sure the compatibility is at least Acrobat 6.0 with Create Acrobat layers turned on.

Open this PDF file in Acrobat Professional. You might need to have the option to view layers turned on to see them. Select the Visual Watermark layer and open Layer Properties.

Use Layer Properties to set the Visual Watermark layer to be off when viewed as a PDF, but to show up when printing and if someone attempts to export the file.

Next apply the Acrobat security settings.

• I prefer Acrobat 7 compatibility to get AES encryption, and I’ve encrypted the whole document.
• I require a password for editing, and I allow recipients to print, but not to change or copy.
• I can now save the PDF.

Immediately upon saving, the document or properties are no longer editable unless I enter the password.

When selecting the print option, I can see that I will have a visual watermark when I print.

Once again this is not a “Digimarc sanctioned” workflow, but merely one digital image techie sharing what has worked for him in the past. Also, Adobe warns that not all products capable of opening a PDF comply with Adobe’s security policies.

• If done correctly, it is likely you can make a very secure document:
• The visual watermark data will dominate the printing of your images.
• The PDF is as secure as Adobe can make it, so posting to the web will retain your metadata in the file.
• The only option this leaves is to take a screen shot of the PDF image and that is why we put the digital watermark into the original image. Below is a screenshot of the PDF I created, opened in Internet Explorer and the Digimarc reader plug-in is detecting the watermark.

As I said before, it’s a bit of an effort to produce just a few images, but if you are putting together a catalog of images this could be a process you might wish to explore.