ABBYY engine
The ABBYY engine requires a paid license.
Supported formats: pdf, pdfa, docx, xls, xlsx, odt, pptx.
Supported languages: Arabic (Saudi Arabia), Bulgarian (Bulgaria), Chinese (Simplified), Chinese (Traditional), Croatian (Croatia), Czech (Czech Republic), Danish (Denmark), English, Estonian (Estonia), French (France), German (Germany), Hungarian (Hungary), Icelandic (Iceland), Italian (Italy), Japanese (Japan), Kazakh (Kazakhstan), Korean (South Korea), Latvian (Latvia), Lithuanian (Lithuania), Norwegian (Norway), Polish (Poland), Portuguese (Brazil), Portuguese (Portugal), Russian (Russia), Serbian (Serbia), Slovak (Slovakia), Slovenian (Slovenia), Spanish, Swedish (Sweden), Turkish (Turkey).
For further information about the engine, see the dedicated documentation from its developer.