OCRmyPDF: A Python repository from solsson

OCRmyPDF adds an OCR text layer to scanned PDF files, allowing them to be searched or copy-pasted.

ocrmypdf                      # it's a scriptable command line program
   -l eng+fra                 # it supports multiple languages
   --rotate-pages             # it can fix pages that are misrotated
   --deskew                   # it can deskew crooked PDFs!
   --title "My PDF"           # it can change output metadata
   --jobs 4                   # it uses multiple cores by default
   --output-type pdfa         # it produces PDF/A by default
   input_scanned.pdf          # takes PDF input (or images)
   output_searchable.pdf      # produces validated PDF output

See the release notes for details on the latest changes.

Main features

Generates a searchable PDF/A file from a regular PDF
Places OCR text accurately below the image to ease copy / paste
Keeps the exact resolution of the original embedded images
When possible, inserts OCR information as a "lossless" operation without disrupting any other content
Optimizes PDF images, often producing files smaller than the input file
If requested, deskews and/or cleans the image before performing OCR
Validates input and output files
Distributes work across all available CPU cores
Uses Tesseract OCR engine to recognize more than 100 languages
Scales properly to handle files with thousands of pages
Battle-tested on millions of PDFs

For details: please consult the documentation.

Motivation

I searched the web for a free command line tool to OCR PDF files: I found many, but none of them were really satisfying:

Either they produced PDF files with misplaced text under the image (making copy/paste impossible)
Or they did not handle accents and multilingual characters
Or they changed the resolution of the embedded images
Or they generated ridiculously large PDF files
Or they crashed when trying to OCR
Or they did not produce valid PDF files
On top of that none of them produced PDF/A files (format dedicated for long time storage)

...so I decided to develop my own tool.

Installation

Linux, Windows, macOS and FreeBSD are supported. Docker images are also available, for both x64 and ARM.

Operating system	Install command
Debian, Ubuntu	`apt install ocrmypdf`
Windows Subsystem for Linux	`apt install ocrmypdf`
Fedora	`dnf install ocrmypdf`
macOS (Homebrew)	`brew install ocrmypdf`
macOS (nix)	`nix-env -i ocrmypdf`
LinuxBrew	`brew install ocrmypdf`
FreeBSD	`pkg install py37-ocrmypdf`
Conda	`conda install ocrmypdf`

For everyone else, see our documentation for installation steps.

Languages

OCRmyPDF uses Tesseract for OCR, and relies on its language packs. For Linux users, you can often find packages that provide language packs:

# Display a list of all Tesseract language packs
apt-cache search tesseract-ocr

# Debian/Ubuntu users
apt-get install tesseract-ocr-chi-sim  # Example: Install Chinese Simplified language pack

# Arch Linux users
pacman -S tesseract-data-eng tesseract-data-deu # Example: Install the English and German language packs

# brew macOS users
brew install tesseract-lang

You can then pass the -l LANG argument to OCRmyPDF to give a hint as to what languages it should search for. Multiple languages can be requested.

OCRmyPDF supports Tesseract 4.0 and the beta versions of Tesseract 5.0. It will automatically use whichever version it finds first on the PATH environment variable. On Windows, if PATH does not provide a Tesseract binary, we use the highest version number that is installed according to the Windows Registry.

Documentation and support

Once OCRmyPDF is installed, the built-in help which explains the command syntax and options can be accessed via:

ocrmypdf --help

Our documentation is served on Read the Docs.

Please report issues on our GitHub issues page, and follow the issue template for quick response.

Requirements

In addition to the required Python version (3.7+), OCRmyPDF requires external program installations of Ghostscript and Tesseract OCR. OCRmyPDF is pure Python, and runs on pretty much everything: Linux, macOS, Windows and FreeBSD.

Press & Media

Going paperless with OCRmyPDF
Converting a scanned document into a compressed searchable PDF with redactions
c't 1-2014, page 59: Detailed presentation of OCRmyPDF v1.0 in the leading German IT magazine c't
heise Open Source, 09/2014: Texterkennung mit OCRmyPDF
heise Durchsuchbare PDF-Dokumente mit OCRmyPDF erstellen
Excellent Utilities: OCRmyPDF
LinuxUser Texterkennung mit OCRmyPDF und Scanbd automatisieren

Business enquiries

OCRmyPDF would not be the software that it is today without companies and users choosing to provide support for feature development and consulting enquiries. We are happy to discuss all enquiries, whether for extending the existing feature set, or integrating OCRmyPDF into a larger system.

License

The OCRmyPDF software is licensed under the Mozilla Public License 2.0 (MPL-2.0). This license permits integration of OCRmyPDF with other code, included commercial and closed source, but asks you to publish source-level modifications you make to OCRmyPDF.

Some components of OCRmyPDF have other licenses, as noted in those files and the debian/copyright file. Most files in misc/ use the MIT license, and the documentation and test files are generally licensed under Creative Commons ShareAlike 4.0 (CC-BY-SA 4.0).

Disclaimer

The software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

solsson/OCRmyPDF