Firstly learn about distinguishing features about different OCR software’s. The major characteristics of OCR software’s are support for languages, speed, user interface, character recognition accuracy, API/SDK, support and consulting, page layout reconstruction accuracy, support for searchable PDF output and stability of the engine when processing large documents. Following is the list of open source OCR software’s:

1. ABBYY FineReader – It is highly accurate and easy to use OCR software that includes host of features including digital camera OCR, intelligent document layouts, image enhancement, barcode recognition and command line integration. FineReader 9 is our pick for OCR software because its document layout retention will save you much time in reformatting documents you convert for editing.
2. SimpleOCR – It is the popular freeware OCR software with hundreds of thousands of users worldwide. SimpleOCR is also a royalty-free OCR SDK for developers to use in their custom applications. If you have a scanner and want to avoid retyping your documents, SimpleOCR is the fast, free way to do it. The SimpleOCR freeware is 100% free and not limited in any way. Anyone can use SimpleOCR for free–home users, educational institutions, even corporate users. Our own freeware OCR application provides acceptable accuracy for those who just need to convert a few pages and can’t justify the cost of commercial OCR software. Developers can use the command line and SDK versions to integrate SimpleOCR with their custom applications.
3. Nuance OmniPage – It is widely regarded as the fastest, most accurate and fully featured OCR software. OmniPage 17 Professional has a unique new feature that lets you convert any type of document to searchable PDF or Word. OmniPage does not have a downloadable demo. Nuance also does not provide free technical support after the first call. For these reasons we recommend the ABBYY and IRIS products instead.
4. IRIS ReadIRIS – It is one of the most affordable OCR software available for business and home users. ReadIRIS Pro provides an extremely accurate OCR recognition rate at a low cost, but still has some of the advanced features that higher priced professional OCR software includes.

Hope, you have learnt about different OCR software’s. Your comments and feedbacks are most welcomed.