Which OCR engine does PDFpen use?
On Intel-based Macs, PDFpen uses the OmniPage OCR engine, version 15.5, from Nuance Communications, Inc. For more info on OmniPage, please choose Help -> License Agreement from the menu or visit http://www.scansoft.com/omnipage/capturesdk/linux/ and note that not all features of the SDK are licensed for use in PDFpen. On PowerPC-based Macs, PDFpen uses the Tesseract Open Source OCR Engine. For more info on Tesseract, please choose Help -> License Agreement from the menu or visit http://code.google.