Ghost4j ( java wrapper for Ghostscript ) is outdated. They're trying to use com.sun.jna 3, which is old af. (and not compatible with new version of JNA)
TODO: - Train tesseract for perfect OCR ( https://github.com/tesseract-ocr/tesseract/wiki/TrainingTesseract ) - Choose 1 type of signing or make proper multioptional one
.Apache PDFBox for pdf manipulation (metadata, splitting in pages, rendering, signing etc) .Tess4J for pure OCR