Adding Invisible Watermark to Your Photos

Have you ever found your photo on strange web site? Nobody contacted you, none paid you any fee for the photo usage before? Even does somebody claim property of your photo? We introduce an application in this article, which can help you protect your property rights. The tool is named SignMyImage and it is developed by Advanced Photo Tools group.


SignMyImage provides insertion of an invisible watermark(text) to the photo – your sign. The sign is not visible at first sight, but the application can find it and read it. Signed photo is slightly changed on several places comparing to original photo. The application is able to detect and read your sign if you use strong jpeg compression(i.e. 50%), even if you scale or crop the photo slightly. An email address is considered as a good for photo signing. The text for photo signing can be up to 27 letters long.

The exemplary case, where SignMyImage can help to protect your rights is as follows:
You take an extraordinary photo, adjust the photo for web presentation and sign the photo and exhibit it on your web site. If someone steals the photo, adjusts it and exhibit it on his/her web pages, you will be able to prove your property rights by the sign detectection.

The rest is up on the law used in your country.

SignMyImage is a shareware and possible to download it on

5 Responses to “Adding Invisible Watermark to Your Photos”

  1. Adam says:

    What if they use a screen capture to steal the image?

  2. FK says:

    Hi, it depends on actual zoom. If the image is scaled lets say by 90% and they capture the screen, the sign should be detected. In other words, the invisible text is added directly to the photo, not to the EXIF or so on. Filip

  3. Don says:

    I am using signmyimage to try and mark my photos. When I try to sign the photo I get a message that tells me the image is too small. What do I do?

  4. FK says:

    Hi Don, you need to have images with resolution 512×512. This restriction is because the algorithm needs at least this size to make the sign robust to resizing and jpeg. But if you are really interested in signing small images, send me an email and I will provide you application where the check on image size is switched off. Filip

  5. FK says:

    Its because the algorithm needs images bigger than some size to make the sign robust to rescaling and jpeg. If you really want to sign small images
    send me an email and I’ll provide you the application with switched off image size checker.

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