Java Watermarking Tool (JWMTool) is a tool, developed in Java, meant to be useful to empirically evaluate limits of digital media (particularly, video) watermarking processes. This information is very important to design watermarking algorithms and techniques.

At the moment, JWMTool supports uncompressed video (YUV format) and it can be used to perform tests where the component to be altered (Y channel or luminance, U channel or blue chrominance, V channel or red chrominance, or even a combination of these) can be selected by the user, as well as the coefficient range to be affected, the amount of variation to be inserted, the modification properties, etc. The process can be chosen to be blind or nonblind, too.