I have a Canon MF642c and the scanner wouldn't work. I tried to use saned but it didn't work with the BJNPlike it did for some other Canon models.
Introducing sane-airscan with packages for the most common distributions: https://software.opensuse.org/download.html?project=home%3Apzz&package=sane-airscan
http........
#if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used
wget http://ffmpeg.org/releases/ffmpeg-3.3.2.tar.bz2
tar -jxvf ffmpeg-3.3.2.tar.bz2
cd ffmpeg-3.3.2/
./configure --disable-yasm
install prefix /usr/local
source path ........