Optical character recognition (OCR)

Optical character recognition, usually abbreviated to OCR, is the translation of:

• raster images
• into text.

All the open source software are based on the tesseract OCR engine.

tesseract imagename outputbase [-l lang] [--oem ocrenginemode] [--psm pagesegmode] [configfiles...]

VietOCR is the only one that I found which:

• simply works
• is easy to use.
• gives great result for screen shot. You have still to check the “ScreenShot Mode” from the Image menu.

For windows, you have also FreeOCR 2.6. It work well but you can't process more than one page at a time. May be it's the good way because you always need to clean the result.

• Javascript: https://tesseract.projectnaptha.com/

• Linux OCR Software Comparison