Activate to decompose complex or special characters in into basic characters. Complex characters are for instance ligatures like 'fi' which will be decomposed into 'fi'. Furthermore special character like long or short hyphens will be normalized to their base character.
Activate to correct typical text recognition mistakes. An example for a common ambiguousness in text recognition is the character 'm' and the syllable 'rn' which appear very similar depending on print quality and font.