OCRmyPDF: OCRmyPDF adds an OCR text layer to scanned PDF files, allowing them to be searched

OCRmyPDF is a free open-source command-line tool that adds an OCR text layer to scanned PDF files, allowing them to be searched or copy-pasted. It is already being used to scan and search millions of heavy PDF files.

Features

Its features include:

• 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
• Keeps your private data private.
• Scales properly to handle files with thousands of pages.