If you want to convert image (scanned) PDFs, you need to purchase the license for Able2Extract Professional PDF Converter. The difference between the Standard and Professional versions of Able2Extract is that the Pro version has an OCR engine that can convert text from a scanned or image-based PDF file, in addition to converting your native PDF files.
If you already have a license for Able2Extract Standard, you don't need to buy a new license for the Professional one. You can upgrade your current license by visiting our Upgrade Center here: http://www.investintech.com/prod_updates.htm
This article refers to Able2Extract Standard, Able2Extract Professional.