Improving optical character recognition accuracy using adaptive image restoration
Junichi Kanai · Journal of Electronic Imaging · 1996
A technique that can improve the optical character rec- ognition (OCR) accuracy of text images is presented. By using the output from an OCR system and a distorted text image, this tech- nique trains an adaptive restoration filter and then applies the filter to the distorted text that the OCR system could not recognize. The restored text image is then reprocessed by the OCR system, and the restored characters are recognized with a higher accuracy than the distorted text. A series of experiments were performed to deter- mine a feasible adaptive restoration filter architecture, to establish this technique's ability to restore uniformly distorted text, and to demonstrate this technique's ability to improve the OCR accuracy of real world text documents. The results of these experiments show that this technique can improve both pixel and OCR accuracy of distorted text images. © 1996 SPIE and IS&T.