NAME

       combine_tessdata - combine/extract/overwrite Tesseract data

SYNOPSIS

       combine_tessdata [OPTION] FILE...

DESCRIPTION

       combine_tessdata(1) is the main program to combine/extract/overwrite tessdata components
       in [lang].traineddata files.

       To combine all the individual tessdata components (unicharset, DAWGs, classifier
       templates, ambiguities, language configs) located at, say, /home/$USER/temp/eng.* run:

           combine_tessdata /home/$USER/temp/eng.

       The result will be a combined tessdata file /home/$USER/temp/eng.traineddata

       Specify option -e if you would like to extract individual components from a combined
       traineddata file. For example, to extract language config file and the unicharset from
       tessdata/eng.traineddata run:

           combine_tessdata -e tessdata/eng.traineddata \
             /home/$USER/temp/eng.config /home/$USER/temp/eng.unicharset

       The desired config file and unicharset will be written to /home/$USER/temp/eng.config
       /home/$USER/temp/eng.unicharset

       Specify option -o to overwrite individual components of the given [lang].traineddata file.
       For example, to overwrite language config and unichar ambiguities files in
       tessdata/eng.traineddata use:

           combine_tessdata -o tessdata/eng.traineddata \
             /home/$USER/temp/eng.config /home/$USER/temp/eng.unicharambigs

       As a result, tessdata/eng.traineddata will contain the new language config and unichar
       ambigs, plus all the original DAWGs, classifier templates, etc.

       Note: the file names of the files to extract to and to overwrite from should have the
       appropriate file suffixes (extensions) indicating their tessdata component type
       (.unicharset for the unicharset, .unicharambigs for unichar ambigs, etc). See k*FileSuffix
       variable in ccutil/tessdatamanager.h.

       Specify option -u to unpack all the components to the specified path:

           combine_tessdata -u tessdata/eng.traineddata /home/$USER/temp/eng.

       This will create /home/$USER/temp/eng.* files with individual tessdata components from
       tessdata/eng.traineddata.

OPTIONS

       -e .traineddata FILE...: Extracts the specified components from the .traineddata file

       -o .traineddata FILE...: Overwrites the specified components of the .traineddata file with
       those provided on the comand line.

       -u .traineddata PATHPREFIX Unpacks the .traineddata using the provided prefix.

CAVEATS

       Prefix refers to the full file prefix, including period (.)

COMPONENTS

       The components in a Tesseract lang.traineddata file as of Tesseract 3.02 are briefly
       described below; For more information on many of these files, see
       http://code.google.com/p/tesseract-ocr/wiki/TrainingTesseract3

       lang.config
           (Optional) Language-specific overrides to default config variables.

       lang.unicharset
           (Required) The list of symbols that Tesseract recognizes, with properties. See
           unicharset(5).

       lang.unicharambigs
           (Optional) This file contains information on pairs of recognized symbols which are
           often confused. For example, rn and m.

       lang.inttemp
           (Required) Character shape templates for each unichar. Produced by mftraining(1).

       lang.pffmtable
           (Required) The number of features expected for each unichar. Produced by mftraining(1)
           from .tr files.

       lang.normproto
           (Required) Character normalization prototypes generated by cntraining(1) from .tr
           files.

       lang.punc-dawg
           (Optional) A dawg made from punctuation patterns found around words. The "word" part
           is replaced by a single space.

       lang.word-dawg
           (Optional) A dawg made from dictionary words from the language.

       lang.number-dawg
           (Optional) A dawg made from tokens which originally contained digits. Each digit is
           replaced by a space character.

       lang.freq-dawg
           (Optional) A dawg made from the most frequent words which would have gone into
           word-dawg.

       lang.fixed-length-dawgs
           (Optional) Several dawgs of different fixed lengths — useful for languages like
           Chinese.

       lang.cube-unicharset
           (Optional) A unicharset for cube, if cube was trained on a different set of symbols.

       lang.cube-word-dawg
           (Optional) A word dawg for cube’s alternate unicharset. Not needed if Cube was trained
           with Tesseract’s unicharset.

       lang.shapetable
           (Optional) When present, a shapetable is an extra layer between the character
           classifier and the word recognizer that allows the character classifier to return a
           collection of unichar ids and fonts instead of a single unichar-id and font.

       lang.bigram-dawg
           (Optional) A dawg of word bigrams where the words are separated by a space and each
           digit is replaced by a ?.

       lang.unambig-dawg
           (Optional) TODO: Describe.

       lang.params-training-model
           (Optional) TODO: Describe.

HISTORY

       combine_tessdata(1) first appeared in version 3.00 of Tesseract

SEE ALSO

       tesseract(1), wordlist2dawg(1), cntraining(1), mftraining(1), unicharset(5),
       unicharambigs(5)

COPYING

       Copyright (C) 2009, Google Inc. Licensed under the Apache License, Version 2.0

AUTHOR

       The Tesseract OCR engine was written by Ray Smith and his research groups at Hewlett
       Packard (1985-1995) and Google (2006-present).

                                            02/09/2012                        COMBINE_TESSDATA(1)