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---+ !OpenFst Library

_OpenFst_ is a library for constructing, combining, optimizing, and
searching _weighted finite-state transducers_ (FSTs). Weighted
finite-state transducers are automata where each transition has an
input label, an output label, and a [[FstQuickTour#FstWeights][weight]]. The more familiar
finite-state acceptor is represented as a transducer with each
transition's input and output label equal.  Finite-state acceptors
are used to represent sets of strings (specifically, _regular_ or
_rational sets_); finite-state transducers are used to represent
binary relations between pairs of strings (specifically, _rational transductions_). 
The weights can be used to represent the cost of taking a particular transition.

FSTs have key applications in speech recognition and synthesis,
machine translation, optical character recognition, pattern matching,
string processing, machine learning, information extraction and
retrieval among others. Often a weighted transducer is used to represent a
probabilistic model (e.g., an _n-gram model_,
_pronunciation model_). FSTs can be optimized by _[[DeterminizeDoc][determinization]]_ and _minimization_,
models can be applied to hypothesis sets (also represented as automata) or cascaded
by finite-state _[[ComposeDoc][composition]]_, and the best results can be selected by [[ShortestPathDoc][shortest-path]] algorithms.

This library was developed at Google Research ([[Main.MichaelRiley][M. Riley]], [[Main.JohanSchalkwyk][J. Schalkwyk]], [[Main.WojciechSkut][W. Skut]])  and NYU's Courant Institute
([[Main.CyrilAllauzen][C. Allauzen]], M. Mohri). It is intended to be comprehensive, flexible, efficient and scale well to large problems. It is an open source project distributed under the [[http://www.apache.org/licenses][Apache]] license.

   * [[FstBackground][Background Material]]
   * [[FstQuickTour][Quick Tour]]
      * [[FstQuickTour#CreatingFsts][Creating FSTs]]
      * [[FstQuickTour#AccessingFsts][Accessing FSTs]]
      * [[FstQuickTour#FstOperations][FST Operations]]
         * [[FstQuickTour#OperationCalling][Calling Operations]]
         * [[FstQuickTour#OperationExample][Example -- FST Application]]  
         * [[FstQuickTour#AvailableOperations][Available Operations]]
      * [[FstQuickTour#FstWeights][FST Weights]]
   * [[FstConventions][Conventions]]
   * [[FstGlossary][Glossary]]
   * [[FstDownload][Download]] %N%
   * [[FstForum][Forum]]
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I	Attachment	History	Action	Size	Date	Who	Comment
jpg	openfst.jpg	r11 r10 r9 r8 r7	manage	14.6 K	2007-06-14 - 05:17	MichaelRiley
This topic: GRM > WebHome
Topic revision: r31 - 2007-07-30 - CyrilAllauzen