didjvu inspired optimization plugin for OCRmyPDF with Gamera-4 djvu binarization and c44 masking
References:
- https://github.com/internetarchive/archive-pdf-tools/tree/pdf-metadata-tooling
- https://github.com/jwilk/didjvu (Python 3 branch https://github.com/FriedrichFroebel/didjvu)
- https://github.com/ocrmypdf/OCRmyPDF
- https://github.com/hsnr-gamera/gamera-4
- https://sourceforge.net/p/djvu/djvulibre-git/ci/master/tree/tools/c44.cpp
This compression-plugin has been decided not to be shipped as part of the OCRmyPDF-source due to license-incompatibilities of the constituent GPL/2-sources and the OCRmyPDF-license.