git clone "https://github.com/jezman/qrworker"
cd qrworker
pip install -r requirements.txt

usage: qrworker.py [-h] [-n {4,6,8}] [-c] files [files ...]

positional arguments:
  files

optional arguments:
  -h, --help            show this help message and exit
  -n {4,6,8}, --number {4,6,8}
                        number QR codes per page
  -c, --codes           save codes in file

python3 qrworker.py to_split1.pdf to_split2.pdf to_split3.pdf -n 6 -c

Splitted complete: Splitted_to_split1.pdf
Parse complete, codes saved: to_split1.txt
Splitted complete: Splitted_to_split2.pdf
Parse complete, codes saved: to_split2.txt
Splitted complete: Splitted_to_split3.pdf
Parse complete, codes saved: to_split3.txt