Chess application whichs allows working with chess PDF books and PGNs.
...Detailed documentation.
Multilanguage currently support for English, Spanish and Catalan.
Dark mode option.
JDK-17 compatibility
You will find more about it at this web sites:
https://chesspdfbrowser.com?origin=sourceforge
https://www.frojasg1.com:8443/downloads_web/web/html/chessPdfBrowser.html?origin=sourceforge
pdfsandwich generates "sandwich" OCR pdf files, i.e. pdf files which contain only images (but no editable text) will be processed by optical character recognition (OCR) and the text will be added to each page invisibly "behind" the images.
pdfsandwich is a command line tool which is supposed to be useful to OCR scanned books or journals. It is able to recognize the page layout even for multicolumn text.