7. The computer-implemented method of claim 2 , wherein removing the potential text regions from the third image not consistent with words comprises: a) performing an image-closing operation on the third image with a predefined structuring element; b) computing connected components in the third image after the image-closing operation; c) checking if the connected components satisfy at least one of the predefined word constraints; and d) removing the connected components not satisfying at least one of the predefined word constraints to create the fourth image.
8. The computer-implemented method of claim 7 , wherein the predefined structuring element is chosen so that it connects the characters corresponding to words.