[Windows] Built-in OCR Library in Windows 7/Server 2008

OCR (Optical Character Recognition) is an interesting issue. I've found that some (built-in) libraries in Windows 7/Server 2008. If you want to develop OCR program without extra fee, you should try it.

1. Window 7 OCR API : In the final answer, you can use thocr.psp.dll ,xocr3.psp.dll, and ximage3b.dll.
2. Using IFilter in C# : If you want to use IFilter, you should read the following topics: (1) Windows TIFF IFilter Installation and Operations Guide, (2) Implementing Control Panel Items (As you want to write a program to access the Control Panel)
3. Converting Images to Text using Office 2007 OCR, OpenXML and Speech Recognition: Use MS Office 2007 OCR library to do OCR.