#90 lensfun-update-data breaks lensfun

[Manuel Coenen]

Using lensfun-update-data to, well, update the data, downloads a new set of xml files where e.g. in slr-sigma.xml the attribute real-focal of the tag distortion moved to a new tag named real-focal-length. lensfun seems to not understand this change and stops reading this file at this entry (Sigma 18-200mm f/3.5-6.3 DC). All entries prior to this point in the file are available e.g. in darktable for correction. All entries including the one where it is changed will not be available. Later files will still be read.

Files containing this change:
actioncams.xml
compact-panasonic.xml
compact-sony.xml
mil-samyang.xml
mil-sony.xml
slr-nikon.xml
slr-sigma.xml
slr-tamron.xml

I am using lensfun-git package in Arch Linux which uses master branch of git://git.code.sf.net/p/lensfun/code and updating the package manually to the latest master did not solve this problem.

[Manuel Coenen]

At the time of writing I was using commit 385aa1. I now updated to latest master 0ec0c3. This also includes the latest version of the xml files in /usr/share/lensfun/version_1. They do not contain the above change.

Using lensfun-update-data will of course not download anything as there is no newer file on the server. I still had a version_1.tar.bz2 file (downloaded an hour ago) lying around and unpacked it to /var/lib/lensfun-updates/version_1 manually but they seem to be ignored (timestamp?) or do no longer cause this issue.

[Torsten Bronger]

I do not fully understand what's going on, but lensfun-update-data does contain code that is supposed to install the correct version number for the Lensfun installed. Possibly, your lensfun-update-data belongs to a newer Lensfun version than the library file?

[Manuel Coenen]

OK, I try to clarify:
When filing this bug I was using a lensfun version based on git master branch commit 385aa1 that I installed a couple of days ago. This installed the included xml files to
/usr/share/lensfun/version_1/<files>

When running lensfun-update-data this morning it correctly recognized version 1 and downloaded http://lensfun.sourceforge.net/db/version_1.tar.bz2. This file was then extracted to
/var/lib/lensfun-updates/version_1/<files>

In these updated files in /var/lib/... attribute real-focal was moved to its own tag real-focal-length which seems to not be understood by lensfun master branch (a change that belongs to another version maybe?).

Next, to verify that my version of lensfun is not too old, I updated my lensfun to latest master branch commit 385aa1. Again included xml files where installed to
/usr/share/lensfun/version_1/<files>
which lets me assume that version 1 is still the latest for master. These files in /usr/share/... have still the "old" format where real-focal is still an attribute of tag distortion.

My assumption now is that the DB files at http://lensfun.sourceforge.net/db/version_1.tar.bz2 are created wrongly and contain changes that are not supposed to be in version 1.

I attached an excerpt from the file slr-sigma.xml contained in http://lensfun.sourceforge.net/db/version_1.tar.bz2 downloaded around 0930 CEST.

[Torsten Bronger]

I found the bug (I think) in the build system on master: I still says version 1. I corrected that. Thank you for the report, and reopen it if it does not fix the problem!

[Manuel Coenen]

Oh, funny. So what I assumed "old" was actually "new" and vice versa. :-D

Updated to latest master commit and now files are installed to version_2. Downloading the latest version_2.tar.bz2 now also matches what is in the git repo (structurally).

Thanks!