OpenLogos Machine Translation

1. OpenLogos Machine Translation
   1. What it is
   2. The OpenLogos License
   3. Availability of OpenLogos Source Code
      1. OpenLogos on Sourceforge
      2. Installation
      3. OpenLogos for Windows
      4. Contact on the OpenLogos Linux port:
   4. Community
   5. Publications and Applications related to OpenLogos

What it is

The LOGOS Machine translation system is one of the largest and most powerful among the commercial machine translation systems. Various text documents in different formats can be submitted to the system and within a short amount of time are translated into different target languages. The result, a raw translation, is already of high language quality. But if required, the result can be post-edited by a human translator. The user saves a significant amount of time and costs especially since the use of different document filters maintain the format of the original document to a high degree.

Currently German and English are the source languages available. The target languages for English include the major European languages (such as French, Italian, Spanish and Portuguese).

The system "can learn" in the sense that a trained user quickly is able to maintain terminology and dictionaries and can also establish his own user dictionary. This is important if the text to be translated belongs to a subject area with specific terminology. The system already has a complex hierarchical system of specialized dictionaries easily accessible for the user. Therefore, from its approach, the LOGOS engine is a "universal problem solving machine" which can process any text in any subject area. "Fine-tuning" or "specialization" is accomplished with the appropriate terminology work.

The open source version of LOGOS is available under the name OpenLogos. The article B. Scott: The Logos Model: An Historical Perspective. In: Machine Translation 18 (2003), pp. 1-72 presents an excellent overview of the Logos approach to machine translation.

Bud Scott, one of the founders of Logos, also created a website with more background information and documents about the Logos system at http://logossystemarchives.homestead.com/ .

The OpenLogos License

OpenLogos has two licensing options.  From a licensing perspective, we have two different products depending on usage and distribution, though technically they have the same source code. These licensing options include:

• The Commercial License, which allows you to provide commercial software licenses to your customers or distribute Logos MT based applications or to use OpenLogos for commercial purposes. This is for organizations that do not want to release the source code for their applications as open source / free software; in other words, they do not want to comply with the GNU General Public License (GPL).
•  For those developing open source applications, the Open Source License allows you to use the software at no charge under the condition that if you use OpenLogos in an application you redistribute, the complete source code for your application must be available and freely redistributable under reasonable conditions. Group Business Software AG, the owners of Logos, bases its interpretation of the GPL on the Free Software Foundation's Frequently Asked Questions.

These conditions pertain to the code as well as to data. Details about the licenses are available in:

• Licensing Policy
• Commercial License
• Open Source License

Availability of OpenLogos Source Code

The commercial LOGOS system from Group Business Software AG had been developed exclusively for the Microsoft-Windows operating system and is based on other commercial products, such as an Oracle database. So its code depends to some extent on non-open source software such as Windows specific libraries and APIs and other modules that cannot be used freely. The code base consists mainly of C++-code with some packages in C and Fortran. Besides embedded SQL-code for interacting with the database, the database itself contains product specific SQL procedures and triggers.

Therefore, the Language Technology Lab of DFKI started in 2005 to prepare an initial version of the Logos system which is truly open source in employing only open source components. This initial port involves among other steps:

• Use of open source development tools and compilers, such as GCC.
• Replacement of non-open code and libraries.
  
• Use open source databases instead of a commercial database. This includes a migration of the database content containing all language specific resources to an open source DB, such as PostgreSQL
  
• Use of open standards instead of vendor specific protocols.
• As a proof of concept for the software migration, Linux was used as target platform for the first OpenSource release of Logos.
  

In addition, the major development and customization tools for the Logos translation system were ported and adapted to the open source version of Logos.

OpenLogos on Sourceforge

• Database as PostgreSQL binary dump
• Source Code for the runtime system
• Source Code for OpenLogos Tools: Installations instructions are contained in the file INSTALL.tools. The tools consist of
• LogosTermBuilder for adapting and extending the translation dictionaries
• LogosTransCenter, a graphical front-end for translating text files.
  
• LogosAdmin for user administration

Installation

OpenLogos for Windows

Contact on the OpenLogos Linux port:

Community

• DFKI hosts a an OpenLogos mailing list dedicated to discussion and exchange of information concerning OpenLogos developments and problems at http://www.dfki.de/mailman/listinfo/openlogos-list.  The list is open for subscription and participation to anybody interested in OpenLogos.
• On LinkedIn, Anabela Barreiro organized an OpenLogos Machine Translation interest group.
• Bud Scott, one of the founders of Logos, created a website with more background information, documents and documentation about the Logos system at http://logossystemarchives.homestead.com/ .
• OpenLogos is open to contribution by other developers through the OpenLogos-MT project on Sourceforge.

Publications and Applications related to OpenLogos

• B. Scott & A. Barreiro: "OpenLogos MT and the SAL representation language". In Proceedings of the First International Workshop on Free/Open-Source Rule-Based Machine Translation / Edited by Juan Antonio Pérez-Ortiz, Felipe Sánchez-Martínez, Francis M. Tyers. Alicante, Spain: Universidad de Alicante. Departamento de Lenguajes y Sistemas Informáticos. 2-3 November 2009, pp. 19-26
• Wikipedia: OpenLogos
• Anabela Barreiro used the OpenLogos translation lexica to build a set of Portuguese-English linguistic resources which are applied to authoring aids and machine translation. Port4NooJ resources are described here and in the article:
  
  • A. Barreiro: "Port4NooJ: Portuguese Linguistic Module and Bilingual Resources for Machine Translation". In Xavier Blanco and Max Silberztein (eds). Proceedings of the 2007 International NooJ Conference. Univ. Autonoma de Barcelona, June 7-9, 2007. Cambridge Scholars Publishing, 2008.
  The script used for extracting the dictionary data from the database is available here.
• A. Barreiro, B. Scott, W. Kasper and Bernd Kiefer: OpenLogos:  Rule-Based Machine Translation: Philosophy, Model, Resources and Customization. In: Machine Translation  25, 2011, pp. 107-126