Thursday, January 5, 2012

Know Your Enemy - Watermark Removal Software

As I've written about before, watermarking your photos and images is the only real way to protect them online.  Otherwise, it's just too easy for someone to save your image and repost it without attribution (or worse, with misattribution).  

Unfortunately, even with a watermark your photos may not be completely safe from would-be thieves.  There's a class of software out there that is specifically made to defeat your watermarks: Watermark Removal Software.

In order to better understand what this software can and cannot due, so that I can better inform Water Marquee users about how best to watermark their images, I decided to give a couple of these applications a try - Photo Stamp Remover 4.3 from SoftOrbis, and Photoupz 1.61 from Photoupz.

To keep the trial fair, I ran the same four photos through each application and did my best to produce a "good" result, meaning as close to complete removal of the watermark as I could achieve without leaving any obvious traces. 

I chose the photos because I thought they would offer an increasing degree of difficulty.

In the results below, you can click on any image for a larger view.

Test Photo 1

Original Image - Watermark is simple and should be easy to remove.

Photoupz Result - Some small artifacts remain.


Photo Stamp Remover Results - Watermark is completely removed.

Both applications did a good job removing the watermark in Test Photo 1, though Photoupz did leave a few small artifacts behind.  However, this watermark is so simple that it would have been easy to achieve the same quality result in Microsoft Paint with a few minutes of work.  My first impression of both applications was that they have an easy to use interface and are very quick at removing the watermark. 

Test Photo 2

Test Photo 2 uses an image as its watermark, and the watermark covers a relatively wide area of the photo. However, the background of the area behind the watermark is very consistent, which should make it easier for the watermark removers.

Original Image - This photo uses an image as its watermark.
Photoupz Result - Barely noticeable artifacts.
Photo Stamp Remover Result - Barely noticeable artifacts.

With Test Photo 2, both applications removed the watermark, but left some very minor artifacts behind. Most people wouldn't even notice the artifacts unless they knew where to look.

Test Photo 3

This photo also uses a logo as its watermark, but the area behind the watermark is much more complex, with some light areas and some dark areas.

Original Image - Frog logo watermark.

Photoupz Result - Watermark completely removed.

Photo Stamp Remover Result - Watermark completely removed.
While both applications did a very good job removing the watermark, the "clouds" inserted by Photoupz aren't as believable as those inserted by Photo Stamp Remover.  Still, it's disconcerting to see how well a job they both did on a watermark I thought they'd have more difficulty with.

Test Photo 4

Test Photo 4 has a large watermark right in the center of the image, covering up a very complicated background.  I was sure this test would give both applications trouble.

Original Image - Large, centered watermark over a complex background.

Photoupz result - Many large and obvious artifacts.

Photo Stamp Remover result - Large blurry section replaces the watermark.
I was pleased to see that, as expected, this image gave both applications difficulty.  Photoupz seemed to "clone" areas from the background into the wrong place in the resulting image, while Photo Stamp Remover left a very blurry section behind in place of the watermark.

Conclusion
I'm sure a professional photo retoucher working with Adobe Photoshop could achieve better results then either of these applications, but it would take far longer.  It took less than a minute in both applications to remove the watermarks from each image, and most of the time they achieved good results.

Based on these results, it seems that the bigger, more "in-your-face" a watermark is, the harder it is to remove.  That's obviously no surprise, but it may make you reconsider the placement and size of the watermark you're using.  I'll talk more about that issue in a follow-up post.