NAME

           mkbingram
          - make binary N-gram from ARPA N-gram file

SYNOPSIS

       mkbingram [-nlr forward_ngram.arpa] [-nrl backward_ngram.arpa] [-d old_bingram_file]
                 {output_bingram_file}

DESCRIPTION

       mkbingram is a tool to convert N-gram definition file(s) in ARPA standard format to a
       compact Julius binary format. It will speed up the initial loading time of N-gram much
       faster. It can read gzipped file directly.

       From rev.4.0, Julius can deal with forward N-gram, backward N-gram and their combinations.
       So, mkbingram now generates binary N-gram file from one of them, or combining them two to
       produce one binary N-gram.

       When only a forward N-gram is specified, mkbingram generates binary N-gram from only the
       forward N-gram. When using this binary N-gram at Julius, it performs the 1st pass with the
       2-gram probabilities in the N-gram, and run the 2nd pass with the given N-gram fully, with
       converting forward probabilities to backward probabilities by Bayes rule.

       When only a backward N-gram is specified, mkbingram generates an binary N-gram file that
       contains only the backward N-gram. The 1st pass will use forward 2-gram probabilities that
       can be computed from the backward 2-gram using Bayes rule, and the 2nd pass use the given
       backward N-gram fully.

       When both forward and backward N-grams are specified, the 2-gram part in the forward
       N-gram and all backward N-gram will be combined into single bingram file. The forward
       2-gram will be applied for the 1st pass and backward N-gram for the 2nd pass. Note that
       both N-gram should be trained in the same corpus with same parameters (i.e. cut-off
       thresholds), with same vocabulary.

       The old binary N-gram produced by mkbingram of version 3.x and earlier can be used in
       Julius-4, but you can convert the old version to the new version by specifying it as input
       of current mkbingram by option "-d".

       Please note that binary N-gram file converted by mkbingram of version 4.0 and later cannot
       be read by older Julius 3.x.

OPTIONS

        -nlr  forward_ngram.arpa
          Read in a forward (left-to-right) word N-gram file in ARPA standard format.

        -nrl  backward_ngram.arpa
          Read in a backward (right-to-left) word N-gram file in ARPA standard format.

        -d  old_bingram_file
          Read in a binary N-gram file.

        -swap
          Swap BOS word <s> and EOS word </s> in N-gram.

       output_bingram_file
          binary N-gram file name to output.

EXAMPLES

       Convert a set of forward and backward N-gram in ARPA format into Julius binary form:
       Convert a single forward 4-gram in ARPA format into a binary file:
       Convert old binary N-gram file to current format:

SEE ALSO

        julius ( 1 ) ,
        mkbinhmm ( 1 ) ,
        mkbinhmmlist ( 1 )

COPYRIGHT

       Copyright (c) 1997-2000 Information-technology Promotion Agency, Japan

       Copyright (c) 1991-2008 Kawahara Lab., Kyoto University

       Copyright (c) 2000-2005 Shikano Lab., Nara Institute of Science and Technology

       Copyright (c) 2005-2008 Julius project team, Nagoya Institute of Technology

LICENSE

       The same as Julius.

                                            02/11/2009                               MKBINGRAM(1)