RWTH OCR - The RWTH Aachen University Optical Character Recognition System

RWTH OCR is a software package containing an OCR decoder together with tools for the development of visual models, based on RWTH ASR. It has been developed by the Human Language Technology and Pattern Recognition Group at the RWTH Aachen University. OCR systems developed using this framework have been applied successfully in several international research projects and corresponding evaluations.

RWTH OCR consists of several libraries and tools written in C++. Currently, only Linux (x86 and x86-64) platforms are supported.



The development of RWTH OCR is ongoing. A Manual is available in the Wiki. Access to the wiki requires registration.

Publications about the theoretical foundations and methods used can be found in the publications page. RWTH ASR is described in detail in Rybach et al. The RWTH Aachen University Open Source Speech Recognition System. Interspeech 2009.

Please post questions in the support forum.


RWTH OCR is an add-on package for RWTH ASR.

RWTH OCR is available only in source form. See the included README.RWTH-OCR for build instructions.

A set of installed tools and libraries is required (Debian package name given in brackets):

After downloading and extracting RWTH ASR, apply the RWTH OCR patch:
cd rwth-asr-0.6.1
gzip -dc rwth-ocr-0.1.patch-for-0.6.1.gz | patch -p1

Terms of Use

RWTH OCR is free software; it can be redistributed and/or modified under the terms of the RWTH OCR License. This license includes free usage for non-commercial purposes as long as any changes made to the original software are published under the terms of the same license. Other licenses can be requested.


To download the software, you have to accept the license terms. Please fill out

I agree to the terms of the
RWTH OCR License
I want to use the documentation wiki. Username, password, and a confirmation link will be sent to the given e-mail address.
I want to receive news about new versions of RWTH OCR by e-mail.

Related Work