unicharset_extractor - Man Page

Reads box or plain text files to extract the unicharset.


unicharset_extractor [--output_unicharset filename] [--norm_mode mode] box_or_text_file [...]

Where mode means: 1=combine graphemes (use for Latin and other simple scripts) 2=split graphemes (use for Indic/Khmer/Myanmar) 3=pure unicode (use for Arabic/Hebrew/Thai/Tibetan)


Tesseract needs to know the set of possible characters it can output. To generate the unicharset data file, use the unicharset_extractor program on training pages bounding box files or a plain text file:

unicharset_extractor fontfile_1.box fontfile_2.box ...

The unicharset will be put into the file ./unicharset if no output filename is provided.

NOTE Use the appropriate norm_mode based on the language.

See Also

tesseract(1), unicharset(5)



unicharset_extractor first appeared in Tesseract 2.00.


Copyright (C) 2006, Google Inc. Licensed under the Apache License, Version 2.0


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

Referenced By

mftraining(1), shapeclustering(1), tesseract(1), unicharset(5).