Make image PDFs searchable with ORPALIS PDF OCR Free
ORPALIS PDF OCR Free is a Windows tool which converts image-based PDFs into fully searchable documents.
There's none of the complexity you can get with full OCR tools. Instead, ORPALIS PDF OCR Free provides a simple front end for its core OCR engine -- the excellent Tesseract -- and manages all the low-level settings itself.
As a result, getting started can be as easy as choosing the source document folder, setting a destination folder and specifying the source document language (English, German, French, Italian and Spanish are supported).
(The program also supports drag and drop, or selection of individual files rather than a folder, but bizarrely the interface can't support more than one of these at a time. Instead you must click "Options" and choose your preferred input mode.)
Once you're ready, click Start and ORPALIS PDF OCR Free works its way through your source files, scanning them with Tesseract and outputting the results.
This can take a very long time, particularly in the free version, but various status tabs keep you up-to-date on progress, and you can browse and test files as they're exported: no need to wait for the entire job to finish.
In our tests, clean and distinct text was recognized without difficulty. Faded scans, slanted text and similar issues caused problems, but they do for all similar programs, and overall ORPALIS PDF OCR Free proved as reliable as we could have expected.
If there are issues, they're mostly due to the restrictions in the Free edition. In particular, a nag screen with a timer pops up occasionally, and the program is only free for commercial use.
In theory, you could avoid all this by upgrading to the Professional edition. This imports files in 90-plus formats, recognizes 60-plus languages, uses multithreading to process multiple documents at the same time, and offers command line support.
The only problem is we can't find out how to buy it, or even how much it costs. There's no mention we can find on the Orpalis site, and clicking "Buy" on the nag screen takes us to an order page where the product isn't listed.
Maybe it'll turn up later. In the meantime, ORPALIS PDF OCR Free is an easy-to-use tool which delivers accurate and reliable results.
ORPALIS PDF OCR Free is a free-for-personal-use application for Windows XP and later.