I have a lot of PDFs already stored on my computer–some are converted JPEGs, some are articles, etc. Will Devonthink Pro Office be able to convert these to OCR or does one have to make them OCR upon first scanning them?
Select an image-only PDF in your database. In the menu bar, choose Data > Convert > to searchable PDF. OCR will be performed and, depending on your settings in Preferences > OCR, the image-only PDF will be sent to the Trash and replaced by the searchable PDF.