I recently replaced an 15 year old HP scanner with a brand new Canon CanoScan LiDE 300. The specs state 10 sec/page in color and 300 dpi.
The scanner is now connected to an desktop computer running Debian 10. But since the default sane-backend was at v1.0.27 which did not support the LiDE 300, we installed sane from an Ubuntu PPA of v1.0.29 with included support.
But now it takes ~16s to scan a page regardless of mode (Color, Gray), resolution (75, 15, 300) and format (jpeg, pnm, tiff). All those combinations takes the same amount. So one might think that the options are wrongly given and the result are always the same, but the resulting files do reflect the parameters given. Ex:
ulf@scan3:~/img$ time scanimage --mode Gray --resolution 150 --format jpeg > img.jpg
real 0m16,089s
user 0m0,395s
sys 0m0,364s
Some other output:
ulf@scan3:~$ sane-find-scanner -q
found USB scanner (vendor=0x04a9 [Canon], product=0x1913 [LiDE 300]) at libusb:002:002
ulf@scan3:~$ scanimage -L
device `pixma:04A91913_46FAC0' is a CANON CanoScan LiDE 300 multi-function peripheral
ulf@scan3:~$ scanimage -V
scanimage (sane-backends) 1.0.29git; backend version 1.0.29
ulf@scan3:~$ cat /etc/apt/sources.list.d/sane-git.ppa.list
deb-src http://ppa.launchpad.net/rolfbensch/sane-git/ubuntu bionic main
My idea was to lower the resolution and go to gray images and by doing so increase the speed. But now its slower than the specs and wont change regardless of settings.
So what am I missing here? I can't find any other parameters to set/change, or what? Could there be some thing in the backend that should be updated directly in the sourcecode? Suggestions, tricks?