OmegaT

OmegaT was first developed by Keith Godfrey in 2000. It was originally written in C++.

The first public release in February 2001[4] was written in Java. This version used a proprietary translation memory format. It could translate unformatted text files, and HTML, and perform only block-level segmentation (i.e. paragraphs instead of sentences).

The development of OmegaT is hosted on SourceForge. The development team is led by Aaron Madlon-Kay. As with many open source projects, new versions of OmegaT are released frequently, usually with 2-3 bugfixes and feature updates each. There is a "standard" version, which always has a complete user manual and a "latest" version which includes features that are not yet documented in the user manual.[5] The updated sources are always available from the SourceForge code repository.[6]

OmegaT handles a translation job as a project, a hierarchy of folders with specific names. The user copies non-translated documents into one named /source/ (or subfolders thereof). The Editor pane displays the source documents as individual “segments” for translation one segment at a time. OmegaT, when directed, generates the (partially) translated versions in the /target/ subfolder.

Other named folders include ones for automatic consultation within the program: /tm/ for existing translation pairs in .tmx format, /tm/auto/ for automatic translation of 100% matches, /glossary/ for glossaries, /dictionary/ for StarDict (and .tbx) dictionaries.

When the user goes to translate a segment in the Editor pane, OmegaT automatically searches the .tmx files in the /tm/ hierarchy for previous translation pairs with similar source sentences and displays them in the Fuzzy Matches pane for insertion into the Editor pane with a keyboard shortcut. The Glossary and Dictionary panes provide similar automatic look-up functions for any glossaries and dictionaries in the corresponding named folders in the project. The optional Machine Translation pane shows machine translations from Google Translate and similar services.

When the user leaves a segment, OmegaT normally first adds the source-target pair to its database in memory. It subsequently saves that database to disk in Translation Memory eXchange (.tmx) format for use another day, in other projects, by other translators, and even with other CAT tools. No change, naturally enough, means no such update. Version 3.1 added a setting for blocking targets equal to their sources, a common slip, plus a keyboard shortcut for overriding it—numbers, source code in programming manuals, etc.

At any point, the user can create partially translated versions of the source files. Note that OmegaT copies source segments verbatim if they have yet to be translated. Before doing so, however, the user is advised to use the Validate menu command to check for tag and other errors. Version 3.1 added a menu command (and keyboard shortcut) for limiting operation to the current file—for partial delivery or quick update, for example.

OmegaT shares many features with proprietary CAT tools. These include creating, importing and exporting translation memories, fuzzy matching from translation memories, glossary look-up, and reference and concordance searching.

OmegaT also has additional features that are not always available in other CAT tools. These include:

• OmegaT starts by displaying a short tutorial called "Instant Start.".
• OmegaT can translate multiple files in multiple file formats in multiple subfolders simultaneously, and consult multiple translation memories, glossaries and dictionaries (limited only by available computer memory).
• With regard to supported file types, OmegaT allows the user to customise file extensions and file encodings. For a number of document types, the user can choose selectively which elements must be translated (e.g. in OpenOffice.org Writer files, choose whether to include bookmarks; in Microsoft Office 2007/2010 files, choose whether to translate footnotes; or in HTML, choose whether to translate ALT text for images). The user can also choose how non-standard elements in third-party translation memories should be handled.
• OmegaT's segmentation rules are based on regular expressions. Segmentation can be configured based on language or based on file format, and successive segmentation rules inherit values from each other.
• In the edit window, the user can jump directly to the next untranslated segment, or go forward or backwards in history. Users can use undo and redo, copy and paste, and switch between uppercase and lowercase in the same way as one would in an advanced text editor. The user can choose to see the source text of segments that have already been translated. The edit pane also has inline spell-checking using Hunspell dictionaries, and interactive spell-checking is done using the mouse.
• Users can insert fuzzy matches using a keyboard shortcut or using the mouse. OmegaT shows the degree of similarity in fuzzy matches using colours. OmegaT can also display the date, time and the name of the user who translated any given segment. Glossary matches can be inserted using the mouse. The user can choose to have the source text copied into the target text field, or to have the highest fuzzy match automatically inserted.
• In the search window, the user can choose to search the current files' source text, target text, other translation memories, and reference files. Searches can be case sensitive, and regular expressions can also be used. Double-clicking a search result takes the user directly to that segment in the edit window.
• After translation, OmegaT can perform tag validation to ensure that there are no accidental tag errors. OmegaT can calculate statistics for the project files and translation memories before the project starts, or during the translation to show the progress of the translation job.
• OmegaT can get machine translations from Apertium, Belazar, Deepl and Google Translate, and display it in a separate window.
• The various windows in OmegaT's user interface can be moved around, maximised, tiled, tabbed and minimised.

Several file types can be translated directly in OmegaT. OmegaT determines the file type by the file extension. The file extension handling and preferred encoding can be customised to override default settings.

OmegaT handles formatted documents by converting formatting to tags, similar to other commercial CAT tools.

• Translation memory
• Computer-assisted translation
• Office Open XML software
• OpenDocument software

• Official web site
• SourceForge project page