[Shotwell] metadata exporting RAW

[Bruno Girin]

Simon,

On 29 December 2010 11:46, Simon Spannagel <simonspa at kth.se> wrote:
> Hej Bruno,
>
> yes, I followed the discussion you're referring to.
>
>> However, it would require smarter meta-data handling that can handle
>> meta-data
>> differently depending on file type.
>
> Don't you do that already now? Or did I get something wrong? You said you
> write the metadata to jpegs only (so you distinguish between them and RAWs).

Yes indeed but in this case the logic is rather simple, it's roughly
of the form:

if image is jpeg, save meta-data with file otherwise do nothing

So in effect, you only have one way to save meta-data, it's just that
you enable the feature for selected types of files rather than all of
them. What you would need to do is generalise this logic so that you
can use several save mechanisms to be applied based on the file type,
something like:

get meta-data handler based on file type
if meta-data handler is not null, save meta-data according to
meta-data handler logic, otherwise do nothing

What differentiates good software from average software is getting
abstraction layers like the meta-data handler abstraction right, so
that implementations can be developed for a large variety of use
cases. In the case of Shotwell, you would need an implementation for
embedded meta-data, one for XMP sidecar files, maybe a separate one
for video files, while keeping the door open for audio files in the
future.

>
> And I completely agree with you that it a too high risk to write in (mostly
> changing and camera model depending) RAW files - I think this is one of the
> golden rules in digital photography: never touch your RAWs.
>
> So maybe one could really do it like this: use the (mostly existing) XMP
> sidecars fpr RAW files and write the data directly into jpegs. Another point
> for this: most people want to access their jpegs over ordinary file manager
> as well - and don't want to be bothered by thousands of XMP sidecars. At
> least I wouldn't like that...

Agreed, the idea is to make it as easy for the user as possible so
store the meta-data in a way that is can be easily exported.

Cheers,

Bruno