Convert a scanned pdf to text with Linux command line using OCRmyPDF

OCRmyPDF is a free utility that allows you to convert a scanned pdf to text (ocr — optical character recognition). In fact, OCRmyPDF adds an OCR text layer to scanned PDF files over the original one, allowing them to be searched or copy-pasted.

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

Installation

Linux, UNIX, and macOS are supported. Windows is not directly supported but there is a Docker image available that runs on Windows.

Users of Debian 9 or later or Ubuntu 16.10 or later may simply

apt-get install ocrmypdf

and users of Fedora 29 or later may simply

dnf install ocrmypdf

and macOS users with Homebrew may simply

brew install ocrmypdf

Usage

Quick convert a single pdf document

ocrmypdf input.pdf output.pdf

Convert all pdf files in a folder

for f in ./*.pdf; do ocrmypdf "$f" "$(basename "$f" ".pdf")_ocr.pdf"; done

References

jbarlow83/OCRmyPDF

OCRmyPDF documentation - ocrmypdf 9.0.3.post6+g68c852a documentation