ONVIF (Open Network Video Interface Forum) is a community to standardize communication between IP-based security products (like cameras or other network video transmitters).
I developed a Java library for the ONVIF spezification. It helps you with the basics (you don't need to learn SOAP e.g.) but you may need to learn a few basics about the ONVIF spezification.
This project has been developed in an academic project from the Hochschule Trier in Germany.
If you want to work the Onvif Java Lib, please consider the code examples.