It seems to me that with Ubuntu Precise Pangolin it is all but easy to do a proper install of SANE from source (git-repo).
I've found other scanning issues trying to find an answer to this, where the output people posted seems to indicate they suffer the same issue (unknowingly).
If I run on a fresh install of Ubuntu 12.04 with compiled SANE source from the git I get:
$ scanimage -V scanimage (sane-backends) 1.0.24git; backend version 1.0.22
(I basically followed the instructions on http://ubuntuportal.com/2012/02/how-to-get-an-canon-canoscan-lide-100-scanner-to-work-in-ubuntu-11-10linux-mint-12.html since I didn't find any other information making sure that sane was not installed prior to installation.)
My primary interest is the epson2-backend. In 1.0.22 it offers the wrong TPU settings for Epson V700 (TPU2-mode wasn't supported in 1.0.22, and the scanner is useless to me if I don't have the TPU2-support).
Since if I ask it to enter transparency mode, it shows 1.0.22 behaviour, it implies that the epson2-backend comes from 1.0.22 and not 1.0.24 even though I just built it.
If I install SANE with prefix to a local folder and run that version of scanimage it still produces the mismatch.
However, on another computer where I installed a custom 1.0.22 build of SANE prior to upgrading to Ubuntu 12.04, I can build and install the same SANE-git locally and have it correctly match backends:
$ ./SANE/bin/scanimage -V scanimage (sane-backends) 1.0.24git; backend version 1.0.24 $ scanimage -V scanimage (sane-backends) 1.0.22; backend version 1.0.22
On this computer the 1.0.24 works correctly in finding TPU2 on Epson V700.
So what am I missing/doing wrong?
(And I want to replace 1.0.22 with 1.0.24 for the whole system, the local build was just debugging.)
Any help would be much appreciated.
Just tried compiling SANE using this instruction on Ubuntu 10.04 and it worked like a charm. However, when I upgraded to 12.04 (really would like to run 12.04), SANE was downgraded to 1.0.22. When trying the same set of instructions on 12.04 I was still out of luck -- the backend missmatch was there again (and I do have libusb-dev installed)
I updated to Ubuntu 12.10 which now has the 1.0.23 SANE drivers. I haven't dared trying to compile from source on 12.10 since 1.0.23 is good enough for me. This is just a work-around and I would still like to know what's up with Ubuntu 12.04.
Tried building SANE on 12.10 both using the above ubuntu-guide and building to a local directory. Both attempts produced backend miss-match.