In order to add custom filters, some knowledge of Java is required.

Adding your own filter is as simple as extending the abstract class TCFilter located in the gui package. The extending class is supposed to be written in the filters package. The javadoc of TCFilter is available here. All that is required is to complete the abstract methods of this class in your extension. Please note the usefulness of some protected methods that come with TCFilter.

For more information on creating custom filters feel free to look at the source code for some existing ones in src/filters directory. You will want to start with TestFilter.java as it is the simplest one and it does not use any complex GUI. For a good gui example, check out the other two, LightenEdges.java and SmoothenTransitions.java