Download Java Image Processing Classes
The classes on this web site are available for download in source code form. If you want to play with the filters, I would strongly recommend downloading the Image Editor. This has customizer dialogs for almost every filter, allowing you to vary all the filter parameters and see the results immediately.
Building
The filters are in source form with an Ant build file. Unpack Filter.jar, go to the Filters folder and type "ant" or just build the filters in whichever way you find comfortable.
License
The downloadable source code on this page is released under the Apache License. Basically, this means that you are free to do whatever you like with this code, but it's not my fault if your satellite/nuclear power station/missile system fails as a result. Have fun!
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this code except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.