[Digikam-users] BUG? move to album / overwrite destination problem

[Remco Viëtor]

On Tuesday 15 May 2012 21:03:32 John Stumbles wrote:
> On 15/05/12 18:23, Peter Albrecht wrote:
> > Hello John,
> >
> > digiKam stores hash-keys for each picture in its database.
> > So it should be able to detect picture movement outside of
> > digiKam.
> 
> Yes, I'm aware of that, and it generally detects movements of picture 
> files quite reliably. However in the particular situation I have here 
> there are identical picture files (they're actually hard-linked) so if I 
> move the instance it has ratings for into the directory containing the 
> one that's not rated I'm pretty sure it would simply think that the 
> rated copy has been deleted.
> 
I think it's actually the hard linking that causes the problem:
Digikam sees that the file you want to copy to exists, asks for permission to 
overwrite, and then tries to open that file for writing, truncating the 
contents. But that file is also opened for reading through the other file 
name... 
And, if you simply move the modified files into the parent directory, you are 
just deleting one of the hard links. Then on next start-up, digikam would 
indeed see that the tagged files have disappeared, and removes the associated 
information from its database.
> 
> > Another (safer) way would be to store the ratings _in_ the
> > jpg-file.
> 
> That would use up unnecessary extra space in my snapshot-backup system 
> storing new copies of picture files when their embedded metadata changed.
> 
Also, storing metadata in the image files isn't recommended for RAW files (and 
perhaps a bad idea for original out-of-camera jpgs as well).

You seem to use the hard links to avoid making a temporary copy. You have to 
do that from outside Digikam, forcing Digikam to check the albums at startup 
(which does slow down startup). And Digikam has no choice but to consider the 
files independant, it has no notion of hard linking afaik. 
Is the use of hard links really worth the hassle and savings on disk space, 
even with your snapshot backups? 

An alternative might be to mark the files you want to work on (green pick 
label?) and then use the right-hand filters tab to show only those. 

Regards, 
Remco