With version 4, tesseract switched to double-dashed command-line parameters, so it is now --psm instead of -psm. Upstream addressed the issue in https://gitlab.gnome.org/World/OpenPaperwork/ pyocr/commit/c136838b46cf49f06ac1dc5f2f9bc16232c11213 Until a newer version is packaged, you can get your stuff going by replacing "- psm" with "--psm" in /usr/lib/python*/dist-packages/pyocr/ {tesseract,builder}.py
Cheers Alan
