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ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. The directory name has changed: no version number in the expanded directory now.
author Franz Glasner <fzglas.hg@dom66.de>
date Mon, 15 Sep 2025 11:43:07 +0200
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1 # Tesseract OCR
2
3 [![Coverity Scan Build Status](https://scan.coverity.com/projects/tesseract-ocr/badge.svg)](https://scan.coverity.com/projects/tesseract-ocr)
4 [![CodeQL](https://github.com/tesseract-ocr/tesseract/workflows/CodeQL/badge.svg)](https://github.com/tesseract-ocr/tesseract/security/code-scanning)
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6 \
7 [![GitHub license](https://img.shields.io/badge/license-Apache--2.0-blue.svg)](https://raw.githubusercontent.com/tesseract-ocr/tesseract/main/LICENSE)
8 [![Downloads](https://img.shields.io/badge/download-all%20releases-brightgreen.svg)](https://github.com/tesseract-ocr/tesseract/releases/)
9
10 ## Table of Contents
11
12 * [Tesseract OCR](#tesseract-ocr)
13 * [About](#about)
14 * [Brief history](#brief-history)
15 * [Installing Tesseract](#installing-tesseract)
16 * [Running Tesseract](#running-tesseract)
17 * [For developers](#for-developers)
18 * [Support](#support)
19 * [License](#license)
20 * [Dependencies](#dependencies)
21 * [Latest Version of README](#latest-version-of-readme)
22
23 ## About
24
25 This package contains an **OCR engine** - `libtesseract` and a **command line program** - `tesseract`.
26
27 Tesseract 4 adds a new neural net (LSTM) based [OCR engine](https://en.wikipedia.org/wiki/Optical_character_recognition) which is focused on line recognition, but also still supports the legacy Tesseract OCR engine of Tesseract 3 which works by recognizing character patterns. Compatibility with Tesseract 3 is enabled by using the Legacy OCR Engine mode (--oem 0).
28 It also needs [traineddata](https://tesseract-ocr.github.io/tessdoc/Data-Files.html) files which support the legacy engine, for example those from the [tessdata](https://github.com/tesseract-ocr/tessdata) repository.
29
30 Stefan Weil is the current lead developer. Ray Smith was the lead developer until 2018. The maintainer is Zdenko Podobny. For a list of contributors see [AUTHORS](https://github.com/tesseract-ocr/tesseract/blob/main/AUTHORS)
31 and GitHub's log of [contributors](https://github.com/tesseract-ocr/tesseract/graphs/contributors).
32
33 Tesseract has **unicode (UTF-8) support**, and can **recognize [more than 100 languages](https://tesseract-ocr.github.io/tessdoc/Data-Files-in-different-versions.html)** "out of the box".
34
35 Tesseract supports **[various image formats](https://tesseract-ocr.github.io/tessdoc/InputFormats)** including PNG, JPEG and TIFF.
36
37 Tesseract supports **various output formats**: plain text, hOCR (HTML), PDF, invisible-text-only PDF, TSV, ALTO and PAGE.
38
39 You should note that in many cases, in order to get better OCR results, you'll need to **[improve the quality](https://tesseract-ocr.github.io/tessdoc/ImproveQuality.html) of the image** you are giving Tesseract.
40
41 This project **does not include a GUI application**. If you need one, please see the [3rdParty](https://tesseract-ocr.github.io/tessdoc/User-Projects-%E2%80%93-3rdParty.html) documentation.
42
43 Tesseract **can be trained to recognize other languages**.
44 See [Tesseract Training](https://tesseract-ocr.github.io/tessdoc/Training-Tesseract.html) for more information.
45
46 ## Brief history
47
48 Tesseract was originally developed at Hewlett-Packard Laboratories Bristol UK and at Hewlett-Packard Co, Greeley Colorado USA between 1985 and 1994, with some more changes made in 1996 to port to Windows, and some C++izing in 1998. In 2005 Tesseract was open sourced by HP. From 2006 until November 2018 it was developed by Google.
49
50 Major version 5 is the current stable version and started with release
51 [5.0.0](https://github.com/tesseract-ocr/tesseract/releases/tag/5.0.0) on November 30, 2021. Newer minor versions and bugfix versions are available from
52 [GitHub](https://github.com/tesseract-ocr/tesseract/releases/).
53
54 Latest source code is available from [main branch on GitHub](https://github.com/tesseract-ocr/tesseract/tree/main).
55 Open issues can be found in [issue tracker](https://github.com/tesseract-ocr/tesseract/issues),
56 and [planning documentation](https://tesseract-ocr.github.io/tessdoc/Planning.html).
57
58 See **[Release Notes](https://tesseract-ocr.github.io/tessdoc/ReleaseNotes.html)**
59 and **[Change Log](https://github.com/tesseract-ocr/tesseract/blob/main/ChangeLog)** for more details of the releases.
60
61 ## Installing Tesseract
62
63 You can either [Install Tesseract via pre-built binary package](https://tesseract-ocr.github.io/tessdoc/Installation.html)
64 or [build it from source](https://tesseract-ocr.github.io/tessdoc/Compiling.html).
65
66 Before building Tesseract from source, please check that your system has a compiler which is one of the [supported compilers](https://tesseract-ocr.github.io/tessdoc/supported-compilers.html).
67
68 ## Running Tesseract
69
70 Basic **[command line usage](https://tesseract-ocr.github.io/tessdoc/Command-Line-Usage.html)**:
71
72 tesseract imagename outputbase [-l lang] [--oem ocrenginemode] [--psm pagesegmode] [configfiles...]
73
74 For more information about the various command line options use `tesseract --help` or `man tesseract`.
75
76 Examples can be found in the [documentation](https://tesseract-ocr.github.io/tessdoc/Command-Line-Usage.html#simplest-invocation-to-ocr-an-image).
77
78 ## For developers
79
80 Developers can use `libtesseract` [C](https://github.com/tesseract-ocr/tesseract/blob/main/include/tesseract/capi.h) or
81 [C++](https://github.com/tesseract-ocr/tesseract/blob/main/include/tesseract/baseapi.h) API to build their own application. If you need bindings to `libtesseract` for other programming languages, please see the
82 [wrapper](https://tesseract-ocr.github.io/tessdoc/AddOns.html#tesseract-wrappers) section in the AddOns documentation.
83
84 Documentation of Tesseract generated from source code by doxygen can be found on [tesseract-ocr.github.io](https://tesseract-ocr.github.io/).
85
86 ## Support
87
88 Before you submit an issue, please review **[the guidelines for this repository](https://github.com/tesseract-ocr/tesseract/blob/main/CONTRIBUTING.md)**.
89
90 For support, first read the [documentation](https://tesseract-ocr.github.io/tessdoc/),
91 particularly the [FAQ](https://tesseract-ocr.github.io/tessdoc/FAQ.html) to see if your problem is addressed there.
92 If not, search the [Tesseract user forum](https://groups.google.com/g/tesseract-ocr), the [Tesseract developer forum](https://groups.google.com/g/tesseract-dev) and [past issues](https://github.com/tesseract-ocr/tesseract/issues), and if you still can't find what you need, ask for support in the mailing-lists.
93
94 Mailing-lists:
95
96 * [tesseract-ocr](https://groups.google.com/g/tesseract-ocr) - For tesseract users.
97 * [tesseract-dev](https://groups.google.com/g/tesseract-dev) - For tesseract developers.
98
99 Please report an issue only for a **bug**, not for asking questions.
100
101 ## License
102
103 The code in this repository is licensed under the Apache License, Version 2.0 (the "License");
104 you may not use this file except in compliance with the License.
105 You may obtain a copy of the License at
106
107 http://www.apache.org/licenses/LICENSE-2.0
108
109 Unless required by applicable law or agreed to in writing, software
110 distributed under the License is distributed on an "AS IS" BASIS,
111 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
112 See the License for the specific language governing permissions and
113 limitations under the License.
114
115 **NOTE**: This software depends on other packages that may be licensed under different open source licenses.
116
117 Tesseract uses [Leptonica library](http://leptonica.com/) which essentially
118 uses a [BSD 2-clause license](http://leptonica.com/about-the-license.html).
119
120 ## Dependencies
121
122 Tesseract uses [Leptonica library](https://github.com/DanBloomberg/leptonica)
123 for opening input images (e.g. not documents like pdf).
124 It is suggested to use leptonica with built-in support for [zlib](https://zlib.net),
125 [png](https://sourceforge.net/projects/libpng) and
126 [tiff](http://www.simplesystems.org/libtiff) (for multipage tiff).
127
128 ## Latest Version of README
129
130 For the latest online version of the README.md see:
131
132 <https://github.com/tesseract-ocr/tesseract/blob/main/README.md>