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

[Remco Viëtor]

On Wednesday 16 May 2012 10:39:43 Jean-François Rabasse wrote:
...
> PS: I have an off-topic question, about something Remco wrote in his
> answer :
> 
> > 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).
> 
> I've often read that kind of warning, on this list. From my naive point
> of view, embedded metadata records, EXIF, XMP, sounds to be a nice thing
> as one keeps all image information into one file. (And XMP sidecar files
> doesn't seem to interoperate well betwen different applications.)
> 
> I'd be really interested in learning what could be potential problems and
> why this seems to be a not recommended practice. Are there reasons related
> to the libexiv2 to be not that stable and reliable, and writing metadata
> could corrupt or destroy the file ? Or are there other reasons ?
> Thanks for making that point become clearer to me.

For me, there are two reasons to avoid writing to RAW files:
- They are the original, irreplacable data that I like to keep in its original 
state.  (I have backups, but still...)
- There is no such thing as _a_ raw format: every camera maker has his own 
formats (yes, plural :( ) And those formats are poorly specified, especially 
wrt to the 'makerdata' EXIF section, so it's very easy to corrupt something 
when writing to such a file. The situation is getting better through a lot of 
hard work from volunteers (not me, I hasten to add), but given the sheer 
number of raw formats in existence, there will probably always be formats that 
are not understood.

Also, RAW files in general only have EXIF data, part of which can be pure 
binary data, and possibly encrypted (makernote..)

Regards, 

Remco