Computer-assisted translation, computer-aided translation or CAT is a form of language translation in which a human translator uses computer software to support and facilitate the translation process.
Contents
- Overview
- Range of tools
- Translation memory software
- Language search engine software
- Terminology management software
- Alignment software
- Interactive machine translation
- References
Computer-assisted translation is sometimes called machine-assisted, or machine-aided, translation (not to be confused with machine translation).
Overview
The automatic machine translation systems available today are not able to produce high-quality translations unaided: their output must be edited by a human to correct errors and improve the quality of translation. Computer-assisted translation (CAT) incorporates that manual editing stage into the software, making translation an interactive process between human and computer.
Some advanced computer-assisted translation solutions include controlled machine translation (MT). Higher priced MT modules generally provide a more complex set of tools available to the translator, which may include terminology management features and various other linguistic tools and utilities. Carefully customized user dictionaries based on correct terminology significantly improve the accuracy of MT, and as a result, aim at increasing the efficiency of the entire translation process.
Range of tools
Computer-assisted translation is a broad and imprecise term covering a range of tools, from the fairly simple to the complicated. These can include:
Translation memory software
Translation memory programs store previously translated source texts and their equivalent target texts in a database and retrieve related segments during the translation of new texts.
Such programs split the source text into manageable units known as "segments". A source-text sentence or sentence-like unit (headings, titles or elements in a list) may be considered a segment, or texts may be segmented into larger units such as paragraphs or small ones, such as clauses. As the translator works through a document, the software displays each source segment in turn and provides a previous translation for re-use, if the program finds a matching source segment in its database. If it does not, the program allows the translator to enter a translation for the new segment. After the translation for a segment is completed, the program stores the new translation and moves on to the next segment. In the dominant paradigm, the translation memory, in principle, is a simple database of fields containing the source language segment, the translation of the segment, and other information such as segment creation date, last access, translator name, and so on. Another translation memory approach does not involve the creation of a database, relying on aligned reference documents instead.
Some translation memory programs function as standalone environments, while others function as an add-on or macro to commercially available word-processing or other business software programs. Add-on programs allow source documents from other formats, such as desktop publishing files, spreadsheets, or HTML code, to be handled using the TM program.
Language search-engine software
New to the translation industry, Language search-engine software is typically an Internet-based system that works similarly to Internet search engines. Rather than searching the Internet, however, a language search engine searches a large repository of Translation Memories to find previously translated sentence fragments, phrases, whole sentences, even complete paragraphs that match source document segments.
Language search engines are designed to leverage modern search technology to conduct searches based on the source words in context to ensure that the search results match the meaning of the source segments. Like traditional TM tools, the value of a language search engine rests heavily on the Translation Memory repository it searches against.
Terminology management software
Terminology management software provides the translator a means of automatically searching a given terminology database for terms appearing in a document, either by automatically displaying terms in the translation memory software interface window or through the use of hot keys to view the entry in the terminology database. Some programs have other hotkey combinations allowing the translator to add new terminology pairs to the terminology database on the fly during translation. Some of the more advanced systems enable translators to check, either interactively or in batch mode, if the correct source/target term combination has been used within and across the translation memory segments in a given project. Independent terminology management systems also exist that can provide workflow functionality, visual taxonomy, work as a type of term checker (similar to spell checker, terms that have not been used correctly are flagged) and can support other types of multilingual term facet classifications such as pictures, videos, or sound.
Alignment software
Alignment programs take completed translations, divide both source and target texts into segments, and attempt to determine which segments belong together in order to build a translation memory or other reference resource with the content. Many alignment programs allow translators to manually realign mismatched segments. The resulting bitext (also known as parallel text) alignment can then be imported into a translation memory program for future translations or used as a reference document.
Interactive machine translation
Interactive machine translation is a paradigm in which the automatic system attempts to predict the translation the human translator is going to produce by suggesting translation hypotheses. These hypotheses may either be the complete sentence, or the part of the sentence that is yet to be translated.