[digiKam-users] Digikam, Tags and Raw files

[Gilles Caulier]

2018-07-29 5:56 GMT+02:00 Matthieu <ermelir at gmail.com>:

> Dear all,
>
> I use Digikam for many years: this is a powerful tool which cover almost
> all the features I expect from this kind of software; bugs are also quickly
> fixed, new features are add very often.
>
> But unfortunately, since tags are not written in the RAW files, I spend
> many time to manage my photo collection of 25k files: I have more than 66%
> of my photos which are raw files, the 33 remaining % are shared in JPG, and
> videos files.
>
> Yesterday, for an unknown reason, my tags tree crashed.
>
> I thought reloading tags from the metadatas stored in my files, but
> because they are not written anymore in the RAW files, the only process I
> have to restore my job is to do manually a second time.
> Many months of job to redo.
>
> How to backup digikam is not the subject of this email :)
>
> I can understand that there are some risk to update RAW files.
>
> But I'm ready to take this risk for the following reasons:
> - For the last 2 or 3 years I updated my RAW files with both Digikam (when
> this feature was available), and with exiftool. I never encountered any
> issue.
> - I use Digikam to help me managing my photo collection, not as a tool to
> view my picture collection: if I define a tag in a raw file in Digikam, I
> expect being able to view this tag in a different software (rawtherapee,
> lightraw, etc)
> - Today, I have some differences between data stored in my RAW files
> content, and the Digikam database.
>
> This is your product, with their own constraints. I use it as it because
> it was helping me to earn time.
> But sometimes, I need to find some workarounds to adapt it as the way I
> manage my pictures.
> Since this feature has been disabled, I was thinking editing correctly all
> my files in Digikam, and then develop a software / plugin / shell scripts /
> which would process the Digikam database and store the missing tags with
> exiftool.
>
> The crash I got yesterday let me think differently...
> So my question now: the checkbox to use the experimental feature to write
> tags in raw files is unchecked since the 5.9 release (those one I use). If
> I'm able to uncheck it in the sources files, will I be able to restore this
> feature?
>

yes. return "true" to this method at line 144, and you will restore the
feature :

https://cgit.kde.org/digikam.git/tree/core/libs/dmetadata/metaengine.cpp#n144



> Or did you also remove all the writing process behind when disabling this
> feature?
>
>
Code is not removed.

In a better world, Exiv2 must have a check internally to see if current raw
file processed is well supported at metadata writting process. In fact, to
be right, Exiv2 must have a generic method to check is current type mime
(and more info for file processed) are well supported at write process to
prevent data corruption. As i know, this method do not exist yet.

The method in DK source code is just a simple hack.

Gilles Caulier
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.kde.org/pipermail/digikam-users/attachments/20180729/08173fa5/attachment.html>