Digital watermark types and general information about digital watermarking for images

Digital watermarking came to be in great demand when sharing information on the Internet became a usual practice. Sharing files online, you never know if someone uses them without your consent. To prevent unauthorized commerce use of your files, you can publish them to the web in the worst quality or don’t publish anything worthwhile at all. It isn’t a good way to solve the problem of unauthorized use, is it? So, you should look for more effective ways of copyright protection, such as digital watermarking.

A digital watermark is a pattern of bits inserted into a digital file – image, audio or video. Such messages usually carry copyright information of the file. Digital watermarking takes its name from watermarking of paper or money. But the main difference between them is that digital watermarks are supposed to be invisible or at least not changing the perception of original file, unlike paper watermarks, which are supposed to be somewhat visible.

Speaking of digital image watermarking, we can divide watermarks into two main groups – visible and invisible watermarks.

A visible watermark is a visible semi-transparent text or image overlaid on the original image. It allows the original image to be viewed, but it still provides copyright protection by marking the image as its owner’s property. Visible watermarks are more robust against image transformation (especially if you use a semi-transparent watermark placed over whole image). Thus they are preferable for strong copyright protection of intellectual property that’s in digital format.

An invisible watermark is an embedded image which cannot be perceived with human’s eyes. Only electronic devices (or specialized software) can extract the hidden information to identify the copyright owner. Invisible watermarks are used to mark a specialized digital content (text, images or even audio content) to prove its authenticity.

Although the copyright protection is the main field of using digital watermarks, they can also be used for such purposes as advertising (adding company’s name and logo as a watermark for promotion rather than for protection) or even adding memo titles to digital photos. It’s obvious that only visible watermarks can satisfy these requirements.

A visible image watermark can be added using a graphics editor (like free MS Paint). But it’s more effective to add digital image watermarks using special watermark software which simplifies watermarking process, speeds up image processing and allows batch add watermarks. Please, look at the examples of visible watermarks added with Bytescout Watermarking Pro software.

The original image:
Sample image without watermark

The same image with the text watermark fitting image size which is robust against cropping (watermark is added using Bytescout Watermarking Pro software):
image protected with digital watermark added using Bytescout Watermarking

Find more information about Bytescout Watermarking Pro software here

Don’t like commercial software? Check our Watermarking freeware here