OpenPDF is an open-source Java library for creating, editing, rendering, and encrypting PDF documents, as well as generating PDFs from HTML. It is licensed under the LGPL and MPL open source licenses.
Install OpenCV (versions between 2.4.2 to 2.4.11 are supported, whereas OpenCV 3.0 is not yet supported). eg: go to "http://opencv.org/", click on Downloads, download ...