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Introduction

Tesseract is an open source Optical Character Recognition (OCR) Engine, available under the Apache 2.0 license. It can be used directly, or (for programmers) using an API to extract typed, handwritten or printed text from images. It supports a wide variety of languages.

Tesseract doesn't have a built-in GUI, but there are several available from the 3rdParty page.

Installation

There are two parts to install, the engine itself, and the training data for a language.

Linux

Tesseract is available directly from many Linux distributions. The package is generally called 'tesseract' or 'tesseract-ocr' - search your distribution's repositories to find it. Packages are also generally available for language training data (search the repositories,) but if not you will need to download the appropriate training data (=< 3.02 or the latest from github.com), unpack it, and copy the .traineddata file into the 'tessdata' directory, probably /usr/share/tesseract-ocr/tessdata or /usr/share/tessdata.

If Tesseract isn't available for your distribution, or you want to use a newer version than they offer, you can compile your own. Note that older versions of Tesseract only supported processing .tiff files.

Mac OS X

You can install Tesseract using either MacPorts or Homebrew.

MacPorts

To install Tesseract run this command:

sudo port install tesseract

To install any language data, run:

sudo port install tesseract-<langcode>

List of available langcodes can be found on MacPorts tesseract page.

Homebrew

To install Tesseract run this command:

brew install tesseract

Windows

An unofficial installer for windows for Tesseract 3.05-dev is available from Tesseract at UB Mannheim. This includes the training tools.

An installer for the old version 3.02 is available for Windows from our download page. This includes the English training data. If you want to use another language, download the appropriate training data, unpack it using 7-zip, and copy the .traineddata file into the 'tessdata' directory, probably C:\Program Files\Tesseract OCR\tessdata.

MSYS2

Install and update MSYS2. Follow instructions at

 http://sourceforge.net/p/msys2/wiki/MSYS2%20installation/ 

Open an MSYS2 command prompt (or the 32-bit or 64-bit command prompts if you plan on building 32-bit or 64-bit things) from the start menu entries.

Install {32-bit,64-bit} MinGW-w64 GCC:

 pacman -S mingw-w64-{i686,x86_64}-gcc

Install tesseract-OCR:

 pacman -S mingw-w64-{i686,x86_64}-tesseract-ocr

and the data files:

 pacman -S mingw-w64-tesseract-ocr-osd mingw-w64-{i686,x86_64}-tesseract-ocr-eng

And you're done.

(These instructions were copied from post by rubenvb at http://stackoverflow.com/questions/29960825/error-during-making-xz-5-2-1-with-mingw-msys )

Cygwin

Released version >= 3.02 of tesseract-ocr are part of 64bit Cygwin

Instruction for cygwin installation is here: https://cygwin.com/cygwin-ug-net/setup-net.html

Tesseract specific packages to be installed:

tesseract-ocr                           3.04.01-1
tesseract-ocr-eng                       3.04-1
tesseract-training-core                 3.04-1
tesseract-training-eng                  3.04-1
tesseract-training-util                 3.04.01-1

Other Platforms

Tesseract may work on more exotic platforms too. You can either try compiling it yourself, or take a look at the list of other projects using Tesseract.

Running Tesseract

Tesseract is a command-line program, so first open a terminal or command prompt. The command is used like this:

  tesseract imagename outputbase [-l lang] [-psm pagesegmode] [configfile...]

So basic usage to do OCR on an image called 'myscan.png' and save the result to 'out.txt' would be:

  tesseract myscan.png out

Or to do the same with German:

  tesseract myscan.png out -l deu

It can even be used with multiple languages traineddata at a time eg. English and German:

  tesseract myscan.png out -l eng+deu

Tesseract also includes a hOCR mode, which produces a special HTML file with the coordinates of each word. This can be used to create a searchable pdf, using a tool such as Hocr2PDF. To use it, use the 'hocr' config option, like this:

  tesseract myscan.png out hocr

You can also create a searchable pdf directly from tesseract ( versions >=3.03):

  tesseract myscan.png out pdf

More information about the various options is available in the Tesseract manpage.

Other Languages

Tesseract has been trained for many languages, check for your language in the Tessdata repository .

It can also be trained to support other languages and scripts; for more details see TrainingTesseract.

Development

Tesseract can also be used in your own project, under the terms of the Apache License 2.0. It has a fully featured API, and can be compiled for a variety of targets including Android and the iPhone. See the 3rdParty page for a sample of what has been done with it.

Also, it's free software, so if you want to pitch in and help, please do! If you find a bug and fix it yourself, the best thing to do is to attach the patch to your bug report in the Issues List

Support

First read the Wiki, particularly the FAQ to see if your problem is addressed there. If not, search the Tesseract user forum or the Tesseract developer forum, and if you still can't find what you need, please ask us there.